Dewdon’s Pre filters are media replaceable and are excellent for most types of air handling systems. Frame dimensions, depth, and filter performance meet the requirements of standard air handling systems.
Our Pre filters are at high efficiency levels G2~G4 EN779; MERV3-8 ASHRAE and are available in 20~95mm depth. Average arrestance is 70%~94% (ASHRAE 52.2-1992) with max airflow rate at 125% of nominal airflow. Our Pre filters are 100% Moisture resistance with thermal Stability of 80℃ for synthetic fiber and 100℃ for glass fiber.
|Frame||Filter Media||Face net|
|Extruded Aluminum/Galvanized steel sheet||Polyester||None/Spot mesh/Expanded mesh|
Rigid structure for demanding applications.
Filter media replaceable, thus cost effective.
Thermal Stability: 80℃ for synthetic fiber, 100℃ for glass fiber.
As Pre filters for intake, exhaust and recirculating air systems, extending the operational lifetimes of the downstream fine filters.
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Drinking water has a normal pH range between 6 and 8.5, meaning that it typically has a level that's just below or just above a neutral pH. There are a number of factors that can lower the pH of water. Acid water can cause metal pipes to corrode and leave blue-green stains on your sinks, faucets, and other plumbing fixtures.
Acid water is water with a low pH, meaning that it's more likely to corrode metal pipes and leach metals out of exposed surfaces. The pH of a solution is a measure of the activity of hydrogen ions (H+) in that solution. In practical terms, it's a measurement of how acid or basic a solution is. The pH scale ranges from 0 to 14, with lower numbers being more acidic.
0 – 6.5 is Acidic
7 is Neutral
7.5 – 14 is Basic
In general, water with a pH that is lower than 7 is considered acid water, with lower numbers being increasingly acidic. Water with a pH that's greater than 7 is considered basic, with higher numbers being increasingly alkaline. The normal range for pH in surface water systems is 6.5 to 8.5 and for groundwater systems 6 to 8.5. Alkalinity is a measure of the capacity of the water to resists a change in pH that would tend to make the water more acidic. The measurement of alkalinity and pH are both needed to determine the corrosiveness of the water.
To put the importance of pH into perspective, remember that the pH scale is logarithmic. Water with a pH of 8.0 is ten times more alkaline than water with a pH of 7.0, and water with a pH of 9.0 is 100 times more alkaline than a solution with a pH of 7.0.
If your water has a low pH, meaning that you have high water acidity, you may see blue-green stains on your plumbing fixtures, faucets, and drains, as well as on bathtubs and sinks. Acid in water can even cause pinhole leaks in copper plumbing. Water that has a pH less than 6.5 could be acidic and corrosive. Acid water has the potential to leach metal ions, including iron, manganese, copper, lead, and zinc, from aquifers, plumbing fixtures, and piping. Because of its corrosive nature, this water could contain elevated levels of toxic metals, damage metal pipes. Many people also find that low pH water has a sour or metallic taste (because of the dissolved metals). It can also discolor laundry as well as plumbing fixtures.
Acid water can be naturally occurring, or caused by a high level of dissolved oxygen. Acidic waters are typically low in buffering calcium minerals, but are high in dissolved carbon dioxide, which can cause the low pH or acidity.
The biggest health problem with acid water is related to copper pipes. Acid in water can dissolve some of the copper from the pipes, where it can be consumed in drinking water. While we all need a small amount of copper in our diets, long-term exposure to high amounts of copper in could cause serious health problems, including liver or kidney damage. Even short-term exposure can cause stomach problems, like nausea and vomiting.
You should address acid water issues if your water has a pH lower than 6.5.
Acidic water is typically treated with a pH water filter that includes a water neutralizer. There are two ways of neutralizing water acidity:
1. Whole House pH Balancing Filters - Calcite the most common material used as a water neutralizer. We actually use Georgia Marble, which is the absolute best form of calcite. It's a natural mineral, also known as calcium carbonate; in some cases, magnesium oxide (sometimes called Corsex) is also used. When water flows through the calcite or magnesium oxide in the water filter, the mineral is dissolved into the water and make it less acidic. This type of filter works best on water that has a pH of 5.5 or higher. This type of pH balancing filter is simple to use, but the pH level may vary with the amount of time the water is in contact with the calcite. Calcite also makes the water harder, so you may need a water softener as part of your treatment system.
2.Proportional pH Balancing Injection Systems - The second method for treating acid water works better on very low pH water but is also more costly. A proportional injection system uses a chemical feed pump to inject a precise amount of water neutralizer solution into the water. This type of system typically uses a form of soda ash (a form of sodium carbonate). A proportional neutralization system assures that the pH is uniform regardless of flow rate and does not add any hardness back to the water. This method is desirable if you do not want to add hardness back to the water
A naturally occurring element, arsenic and its compounds are very poisonous. If you get your water from a private well, it's important to have your water tested regularly to make sure that it's safe to drink. Read on to learn more about the health risks of arsenic in water and the different methods available for treating contaminated water.
Arsenic is a metalloid element that is found naturally in rocks, soil, and plants. Most forms of this element are extremely toxic and dangerous to humans. The source of arsenic in water is often natural deposits in the ground that contaminate aquifers and wells. Contamination can also be caused by poor agricultural and industrial practices.
This element has a variety of industrial uses, and it's found in some paints and dyes, soaps, semiconductors, and in some metal alloys. Arsenic was a very common wood preservative used for decades in the United States, but it's no longer used to treat wood for household use. This element is also released into the environment through coal burning, mining operations, and copper smelting. In agriculture, arsenic can be found in some fertilizers, as well as a number of pesticides and herbicides.
Because arsenic has no taste, odor, or color, there really is no easy way to know if there is arsenic in drinking water. Anyone who gets their water from a well or other private source should make sure that the system is tested for arsenic regularly.
As groundwater passes through rocks and soil that contain arsenic, this element can be dissolved into the water. In addition, arsenic used for industrial or agricultural purposes can contaminate drinking water supplies.
Arsenic is poisonous, and drinking arsenic in water can be deadly. Exposure can cause headaches, drowsiness, diarrhea and vomiting, and discoloration of the skin and fingernails. Over time, chronic exposure may lead to severe stomach pain, numbness in the extremities, convulsions, paralysis, and blindness. Arsenic has also been linked to several different types of cancer.
It's important to note that while arsenic in drinking water is dangerous, it's not as much of a concern in water used for other purposes. Arsenic is not absorbed through the skin very easily, and it won't become airborne if it's dissolved in water. Unless levels are very high – more than 500 ppb – it's OK to use water that contains arsenic for bathing and other household chores.
Because arsenic is highly toxic, the maximum contaminant level (MCL) is .010 ppm or 10 ppb. This figure is based on both organic and inorganic forms.
Arsenic is found naturally in the soil, so it's often found in higher levels in groundwater than in other water sources. When large amounts of water are removed from the ground through wells and municipal systems, the arsenic that's naturally held in rocks may be exposed and released. In other words, the more the water is used in locations with high arsenic deposits, the more likely it is to be contaminated. In the U.S., the Environmental Protection Agency has set the standard for arsenic in drinking water at 10 parts per billion (ppb).
Compared to the rest of the United States, the Western states tend to have the highest arsenic levels – often above the EPA's standard of 10 ppb. In addition, some parts of the Midwest and New England have high levels of arsenic in water, although most systems in these areas are under the EPA limit. Part of the reason why testing is so important is that "hot spots" can develop even where arsenic is not a common problem. If you're concerned about arsenic in your water, consult your local health department or your state geological survey office.
Depending upon what a detailed water analysis of your water reveals, there are multiple ways of removing arsenic from water supplies. One of the most effective and affordable arsenic water filter methods is reverse osmosis (RO), with studies indicating that it may be up to 95% effective. RO systems are typically only used to produce drinking water, although whole house systems are available. If there is also iron in the water, then there are special resin medias that will bind with the iron and arsenic and remove them from the water. Before any sizing or determination of system design can be started, however, a detailed water analysis must be completed.
We all need access to clean water to stay healthy. So what do you do when your water has become contaminated with bacteria, viruses, cysts, or other microorganisms? US Water Systems offers both water testing kits and a number of options for water disinfection to address a wide range of microorganism contaminants, including coliform in water. Call our Certified Water Specialists at 1-800-608-8792 to discuss your water problems and our recommended solutions.
There are a range of microorganisms, including bacteria, protozoa, and viruses, that live and thrive in water. While most people in the United States get their water from a municipal water treatment plant where the water has been disinfected to kill any biological contaminants, private water sources – such as wells – can become contaminated. If you suspect that your water supply, no matter the source, may be contaminated, it's extremely important to have it tested and treated right away. There are many different types of microorganisms in water and may make you very, very sick. One of the most common tests measures the level of coliform in water, which is a strong indicator that the water may be contaminated with other pathogens.
Symptoms: Many waterborne pathogens cause gastrointestinal illness with flu-like symptoms, especially in young people, those with compromised immune systems, or the elderly. Bacteria in water are typically swallowed, which is why many of the disease symptoms start in the stomach or intestines.
Causes: There are a number of ways that disease-causing microorganisms can get into your water. Fecal coliform bacteria, including E. coli are found in high amounts in the intestines and feces of people and animals. Cryptosporidium and giardia protozoa often come from surface water contaminated with the feces of wild animals. These and other microorganisms often get into the water supply through the feces of humans and animals, including cattle and other farm animals, cats and dogs, and wildlife. This material can be washed into storm drains, streams, reservoirs, and other bodies of water, and then may travel into the water system. Leaky pipes and sewer connections, septic tanks that don't work properly, an improperly sealed well, or problems at a water treatment plant can all allow these contaminants to get into your water supply and make you sick.
Health Concerns: Water that contains biological contaminants can be extremely dangerous. While many bacteria in water, such as E. coli, or protozoa like Cryptosporidium parvum, cause flu-like symptoms and gastrointestinal discomfort in otherwise healthy individuals, they can cause serious dehydration and even death in those who are very young, very old, or have compromised immune systems. Other far more serious illnesses can also be spread through contaminated water, including hepatitis, typhoid, dysentery, and cholera, all of which can result in severe illness or even death.
Action Level: Wells should be regularly tested for the presence of coliform in the water. Municipal systems are routinely tested for this bacteria as well. Drinking water should immediately be treated if the presence of any bacteria is detected.
Coliform bacteria are present in the environment and in the feces of all warm-blooded animals and humans. The term actually encompasses multiple different types of bacteria, all of which are grouped together because they have similar characteristics. Most types of bacteria in this group don't cause serious illness, but their presence in drinking water indicates that disease-causing organisms (pathogens) could be in the water system.
Most dangerous protozoa and bacteria in water supplies come from the feces of humans or animals. Testing drinking water for all possible pathogens is complex, time-consuming, and expensive, but it is relatively easy and inexpensive to test for coliform in water. If this type of bacteria are found in a water sample, it's an indicator that the water has been exposed to some type of contamination. Water specialists can then work to find the source of contamination, what pathogens are actually in the water, and restore safe drinking water.
There are three different groups of coliform bacteria; each has a different level of risk:
Total coliform Fecal coliform E-coli
The total coliform group is a large collection of different kinds of bacteria. Fecal coliforms are types of total coliform that mostly exist in feces. E. coli is a sub-group of fecal coliform. When a water sample is sent to a lab, it is tested for total coliform. If total coliform is present, the sample will also be tested for either fecal coliform or E. coli, depending on the lab testing method.
Unlike the photo to the left, it is not always obvious not to drink the water. Coliform bacteria are commonly found in the environment (e.g., soil or vegetation) and are generally harmless. If a water sample indicates that there is coliform in the water but no fecal coliform, the source is probably environmental. If environmental contamination can enter the system, however, there may also be a way for other dangerous pathogens to enter the system. Therefore, it is important to find the source and resolve the problem.
Fecal coliform bacteria are a type of coliform bacteria and get their name because they are commonly found in the intestines and feces of people and animals. If a drinking water sample contains fecal coliform, it's likely that sewage or other fecal matter has recently contaminated the water. This indicates a high risk that pathogens are present.
E. coli is a type of fecal coliform group, and probably the best known. Food and water contaminated by certain types of E. coli have caused disease outbreaks around the country and gotten a lot of media attention. Most E. coli bacteria in water are harmless, but their presence almost always means that there has been recent fecal contamination.
When routine water testing indicates coliform bacteria in water, it's common to collect additional samples and repeat the tests to help determine if there is an actual problem with the water system. Once the tests are confirmed, it's important for the entire water system – whether municipal or private – to be inspected to find the source of the contamination. Leaky pipes, septic tank problems, well mechanical problems, and other system issues can all lead to water bacteria contaminating the water supply. Once the source is identified, it can be repaired or corrected to eliminate the contamination.
After repairs are complete, the system should be flushed and, if you're on a private well, you may need to shock the well with chlorine. This should kill any microorganisms in the water. If there are ongoing or repeated contamination issues, you may want to install a continuous chlorination system.
If you are on a private water supply, we strongly encourage you to protect yourself and your family's health with one of our trusted and reliable disinfection systems. While chlorine is a good choice for seriously contaminated water, there are other easier and more affordable options for routine use.
Quantum disinfection is recent innovation that kills up to 99.9999% of microorganisms and bacteria in water. It uses no electricity and adds nothing to your water supply.
Ultraviolet (UV) disinfection has been the technology of choice for several years now to render bacteria (including coliform in water) harmless. It's affordable and adds nothing to the water.
Ozone disinfection is extremely effective at killing pathogens, but it's also relatively expensive. This type of system is not recommended for most homes.
Additionally, US Water has a complete line of lake and pond water treatment systems that include chlorination and ultraviolet for the treatment of surface waters.
No matter where you get your water from, it's at risk for chemical pollution. Water from private wells may be at relatively high risk, but the disinfecting chemicals in water from your local municipal water treatment plant can also produce byproducts that are potentially dangerous to your health. Learn more about the types of chemicals that may be found in your water, as well as the best chemical filters to you to give you cleaner, healthier water.
A number of different chemicals may be found in your water, depending in part on where your water comes from. Many municipal water treatment plants use chlorine or chloramines to disinfect water, and both of these chemicals can linger and make their way into your drinking water. In addition, as disinfection chemicals break down, they may product byproducts, including trihalomethanes (THMs) – a known cancer causing agent. And while water treatment plants use filters and other methods to remove a wide range of potential contaminants, there are a significant number of unregulated chemicals in water that have not legally mandated limits.
If you get your water from a private well, the risk of chemicals in drinking water may be even higher. The water in wells comes from underground aquifers that are fed with groundwater. This water may be exposed to a wide variety of chemicals and pollutants, including pesticides, spilled fuels, and toxins that have not been disposed of properly, including prescription medications and various types of hazardous waste. Older industrial chemicals, including polychlorinated biphenyls (PCB) and (trichloroethylene) TCS, can also be found in the water in some locations.
It's often very difficult to tell if there is chemical pollution in the water in your home or business. Many chemicals are very hard to detect and may show no obvious indications. Water treatment plants test for all regulated chemicals and toxins, but they typically don't look for unregulated pollutants. If you're concerned about your water quality, you need to have your water tested.
Many of the chemicals in water are known as endocrine disruptors, which means that they can interfere with the hormones in living creatures. Endocrine disruptors have been linked to birth defects, developmental disorders, and the growth of cancerous tumors.
Because many of the chemicals in drinking water can be bad for your health, it's a good idea to use a water treatment system to remove them no matter their level. Disinfection chemicals like chlorine can make your water taste and smell bad, even if the levels are within legally allowable limits. It's always a good idea to have your water tested for chemicals and to use the appropriate type of chemical water filter.
Warning Dangerous ChemicalsUnfortunately, chemical pollution in water is a common problem all across the United States. A 2009 study by the Environmental Working Group found that millions of people in the U.S. were exposed to a variety of potentially toxic chemicals in water above the health-based guidelines. Many of these chemicals are unregulated, so there are no legal limits for how much may be found in water. In addition, water that is treated at the municipal level often has disinfection chemicals added to it, which bring with them their own problems.
The best technology available for removing chemicals in water is activated carbon (GAC). This material, sometimes just referred to as "carbon" or "charcoal, " is the recommended treatment for most of the water contaminants listed by the EPA. Carbon filters are very common and affordable, and nearly all water filtration systems include one. This means that most water filtration systems remove some amount of chemicals in drinking water, although the effectiveness of the filter is directly related to how much carbon is used and how the filter is designed.
Carbon filters have many tiny clusters of carbon atoms, all stacked on top of each other. These filters work through a process called adsorption, which means that the chemical molecules adhere the highly porous surface of the carbon. GAC is specially treated to give it a very high surface area, allowing lots of space for the chemicals in water to stick. In fact, just 1 pound of GAC has the surface area equivalent to up to 150 acres!
GAC can made from the carbon produced from a variety of materials, such as peanut shells, coconut shells, or coal. It can be produced in several different ways, but often the source material is heated slowly in an inert atmosphere to produce a high carbon material. The carbon is activated by passing oxidizing gases through it at extremely high temperatures, which produces the pores needed.
How effective a carbon filter is at removing chemicals in drinking water depends on several factors, including the physical properties of the GAC and what it's made out of. In addition, the properties of the water being treated, such as its pH, temperature, and flow rate, all have an impact. Of course, the amount and types of chemicals in the water are also an important factor.
If you need a GAC filter to remove chemicals in water, you have several options available. A variety of pitcher and faucet filters are on the market. You can also choose from countertop and undersink filters, which may be more effective. Reverse osmosis units produce exceptionally clean water, and these units typically include at least two good carbon filters before the RO membrane. You can also choose a whole house carbon filter, which uses either a backwashing tank or filter cartridge. Catalytic carbon filters are an excellent option for the removal of chloramines and other volatile organic chemicals.
It's important to note that GAC filters can become a source of contamination if they are not replaced periodically. Chemical contaminants can build up in the filter over time, and may be released into the water in unexpectedly high concentrations. Organic matter can also build up, allowing for bacteria to grow quite quickly. As a result, it is an excellent idea to install a quantum disinfection system or ultraviolet (UV) disinfection after any carbon filters installed on well water, unless other disinfection processes (such as ozone, hydrogen peroxide, or chlorine) are used.
Chloramine is a water disinfection chemical used in many water treatment plants to kill bacteria and other dangerous pathogens. It's often used as an alternative to free chlorine because, although it's less effective, it creates fewer byproducts and stays in the system for a longer period of time, providing additional protection as it moves through the pipes and into homes. Unfortunately, chloramine in water has a number of potential side effects, including giving the water a bad taste and smell.
Chlorine has been used to disinfect water for more than a century, and it's often credited with saving many lives by producing drinking water that wasn't contaminated with bacteria, viruses, and many types of protozoan cysts. While it's an extremely effective disinfectant, chlorine in drinking water can cause a number of side effects as well as producing potentially dangerous disinfection byproducts. Learn more about how chlorine is used and how to remove chlorine from water.
Chlorine is a gaseous chemical element that's found in many different compounds. It's an extremely strong oxidizing agent, which means that it can cause other substances to lose their electrons. That's why it's such an effective disinfectant “ when most living cells encounter chlorine in water, they lose electrons from their outer membranes, which causes them to lose their structure, break down, and die. This also means that chlorine is toxic to humans and other animals.
While the chlorine in drinking water does have side effects, it's not necessarily dangerous in and of itself. Washing or swimming in water that contains chlorine can lead to dry skin and hair, and cause burning in the eyes. Many people also dislike the taste and smell of chlorinated water. In addition, this chemical can react with organics in water to produce disinfection byproducts (DBP) that could be dangerous.
Trihalomethanes (THMs), one of the disinfection byproducts of chlorine in water, is a known carcinogen, which means that it may cause cancer. This and other DBPs have also been linked to liver and kidney problems, developmental disorders, and respiratory issues. Unlike some other disinfectants, chlorine can be absorbed through the skin and inhaled; it's not necessary to drink chlorine in water for it to get into your body.
Aside from the health side effects, some people find that using chlorinated water means that the vegetables they grow may not be as green, and foods cooked in it may have a strange taste. Plants and gardens can also be negatively affected. Chlorine also breaks down rubber, so plumbing parts made of this material can leak.
Most water quality experts believe that no amount of chlorine or chlorine byproducts are acceptable in water.
There's no question that adding chlorine in drinking water has saved many, many lives. Cholera and typhoid were two of the leading causes of death in the U.S. in the 19th Century, and both were nearly wiped out after municipalities started putting chlorine in water. Once the water has reached your home, however, the chlorine has done its job and needs to be removed “ along with any byproducts.
Most people prefer to remove chlorine from water before drinking it to improve the taste and smell if for no other reason. Even at levels as low as 0.5 parts per million (ppm), it can be a problem in water used for drinking or bathing. Swimming pools, by comparison, may have a level of 2.0 to 3.0 ppm.
“Showering is suspected as the primary cause of elevated levels of chloroform in nearly every home because of the chlorine in the water.” - DR. LANCE WALLACE - U.S.E.P.A.
“A long hot shower can be dangerous. The toxic chemicals are inhaled in high concentrations.” - Dr. John Andelman - BOTTOM LINE
“Skin absorption of contaminant has been underestimated and ingestion may not constitute the sole or even primary route of exposure.” - Dr. Halina Brown - AMERICAN JOURNAL OF PUBLIC HEALTH
“Showers - and to a lesser extent baths - lead to a greater exposure to toxic chemicals contained in drinking water supplies than does drinking the water.” - Ian Anderson - NEW SCIENTIST
“Drinking chlorinated water may double the risk of bladder cancer, which strikes 400, 000 people a year.” - IS YOUR WATER SAFE? - U.S. NEWS & WORLD REPORT
If you get your water from the municipal water treatment system, it has almost certainly been treated with some form of disinfectant, and chlorine is one of the most common. Dechlorinated water can be made in your home pretty easily “ in fact, a granular activated carbon (GAC) filter is one of the best ways to remove chlorine from water. GAC is an effective chlorine water filter because it's made with a very high surface area and high adsorption properties. The chlorine in water sticks to the surface of the carbon.
Fluoride Symptoms: This is a very polarizing debate: One side says that "fluoride in water is known to prevent tooth decay" while the other side says that "fluoride is toxic and has resulted in deaths from acute poisoning."
Causes: Many cities actually add fluoride to the water which is why it is many water supplies.
Health Concerns: An active ingredient in many pesticides and rodenticides is fluoride. which is accutely more poisonous than lead. Overdose leads to serious toxic symptoms. Some experts feel that water fluoridation can lead to cancer, diabetes, thyroid and neurological disorders, heart disease, arthritis and osteoporosis.
Action Level: Any level is frequently undesirable.
Here is what one expert says: "Fluoride and fluoridation will go down as one of the greatest controversies of the 20th century. Up until the early 1940's, fluorine's effect on life was always deemed poisonous. It was proven to be altering enzymes used by living organisms to carry out a multitude of essential processes. Fluorine, the most reactive element on the planet, is also the strongest free radical. Scientists in the 1930's and 1940's experimented with this element to create the most deadly nerve gasses, rocket fuel, and radioactive U235 for the bomb. As a wood preservative, rodenticide and insecticide, fluorine compounds are second to none. As an Orthodontist, I began investigating the increasingly prevalent lines and spots that I saw on the enamel of children. Like rings on a tree, they indicate excessive fluorine exposure. I started to ask the question, 'How does fluorine cause these marks?' Chronic doses of fluoride, like arsenic and lead, accumulate in our bodies causing a blockage in the way cells breathe and leads to the malformation of collagen. Cancer, diabetes, thyroid and neurological disorders, hormonal imbalances, heart disease, arthritis and osteoporosis have all been linked to chronic fluoride ingestion. We are now exposed to increasing doses of fluoride from toothpaste, rinses, water, food, medicines, showering, bathing, and even the air that we breathe. Our environment has become a literal fluoride dumping ground."
Symptoms: Scale build-up in plumbing systems, including pipes, faucets, appliances, and water heaters. High soap and detergent usage and stiffer dingy clothes.
Causes: As water moves through soil and rock, it dissolves very small amounts of minerals and holds them in solution. Calcium and magnesium dissolved in water are the two most common minerals that make water hard.
Health Concerns: Hard water is high in dissolved minerals, specifically calcium and magnesium. Hard water is not a health risk, but a nuisance because of mineral buildup on fixtures and inside pipes as well as poor soap and/or detergent performance.
Action Level: Water over 10.5 gpg (180 mg/l) is considered extremely hard, but savings are realized at levels over 3 gpg (51 mg/l).
Hard water is high in dissolved minerals, specifically calcium and magnesium. Hard water is not a health risk, but a nuisance because of mineral buildup on fixtures and inside pipes as well as poor soap and/or detergent performance.
Water is a good solvent and picks up impurities easily. Pure water is tasteless, colorless, and odorless, and is often called the universal solvent. When water is combined with carbon dioxide to form very weak carbonic acid, an even better solvent results.
As water moves through soil and rock, it dissolves very small amounts of minerals and holds them in solution. Calcium and magnesium dissolved in water are the two most common minerals that make water hard. The degree of hardness becomes greater as the calcium and magnesium content increases.
Laundry : Clothes washed in hard water often look dingy and feel harsh and scratchy. The hardness minerals combine with some elements to form insoluble salts, making them difficult to remove. Soil on clothes can introduce even more hardness minerals into the wash water. Continuous laundering in hard water can damage fibers and shorten the life of clothes by up to 40 percent.
Bathing - Bathing with soap in hard water leaves a film of sticky soap curd on the skin. The film may prevent removal of soil and bacteria. Soap curd interferes with the return of skin to its normal, slightly acid condition, and may lead to irritation. Soap curd on hair may make it dull, lifeless and difficult to manage.
Dishwashers - When washing dishes, especially in a dishwasher, hard water may cause spotting and filming on your glassware and other utensils. The minerals from hard water are released faster when it comes into contact with heat, causing an increase in the amount of spotting and filming that occurs. This problem is not a health risk, but it can be a nuisance to clean and makes your glasses and silver spotted and dingy.
Hard water also contributes to inefficient and costly operation of water-using appliances. Heated hard water forms a scale of calcium and magnesium minerals, limescale deposits, that can contribute to the inefficient operation or failure of water-using appliances. Pipes can become clogged with scale that reduces water flow and ultimately requires pipe replacement. Limescale has been known to increase energy bills by up to 25%.
Solar heating, often used for heating swimming pools is prone to limescale buildup, which can reduce the efficiency of the electronic pump and therefore the overall systems performance will deteriorate.
Hard water is not a health hazard. In fact, the hard drinking water generally contributes a small amount toward total calcium and magnesium human dietary needs, and in some instances, where dissolved calcium and magnesium are very high, water could be a major contributor of calcium and magnesium to the diet.
The ideal solution would be to leave the calcium in the water, but alter its state so that it couldn't form limescale. This is what the GreenWave Salt-Free System does.
If you are on a municipal water system, the water supplier can tell you the hardness level of the water they deliver. If you have a private water supply, you can have the water tested for hardness. US Water also offer a number of water tests HERE.
Once you've tested your water supply, the hardness of your water will be reported in grains per gallon, milligrams per liter (mg/l) or parts per million (ppm). One grain of hardness equals 17.1 mg/l or ppm of hardness.
If there is iron in your water, you probably know it! Iron can cause rusty water, which leaves black, orange, or red stains on your plumbing fixtures, toilets, and other surfaces. This mineral can also give you water that tastes like metal. And when you have iron, you can typically have manganese in the water as well. Manganese is more difficult to remove from the water and it leaves brown or black stains. Neither iron nor manganese is desirable in your water and US Water Systems can eradicate both iron and manganese completely. The US Water OXi-Gen System is the most robust one on the market.
Our Synergy Twin-Alternating Water Softener is also a great choice on water that has smaller amounts of iron or manganese in it. The best scenario is to filter the water with an OXi System, followed by the Synergy (if the water contains hardness as well). The Synergy regenerates with soft water and fills the brine tank with soft water and is exceptional at removing manganese in the water. It is vitally important that a Comprehensive Lab Water Test is performed on your water before attempting to remove iron or manganese.
When you have high levels of iron in your water, you will likely know it from the black or red stains left by this mineral. These stains not only accumulate on toilets and showers, iron can discolor your clothing and anything else that untreated water touches. Iron is often found with manganese, another mineral that leaves black or dark brown stains and which can build up deposits in your pipes. Water with high levels of iron and manganese most often comes from wells or other private water sources.
It is common for water that contains iron to also have levels of hydrogen sulfide and/or arsenic. In many cases, all of these contaminants can be removed in exactly the same manner that you remove iron.
Iron in water typically comes from the rocks and soil around the water source. As water moves through the rocks and into the well or aquafer, it dissolves the iron that's naturally found in the environment. Manganese is often found in the same sources as iron, although it's less common.
There are many types of iron, but for our purposes we generally divided them into two main categories: (1) soluble or ferrous iron and (2) insoluble or ferric iron. Soluble iron, or "clear water" iron oxidizes to insoluble or red iron in the presence of oxygen either in the well or in your home. You can tell if you have soluble iron in water by pouring a glass of cold clear water. When allowed to stand in the presence of air, reddish brown particles will appear in the glass and eventually settle to the bottom. When insoluble iron, or red water iron, is poured into a glass, it appears rusty or has a red or yellow color. Insoluble iron can create serious taste and appearance problems in water.
In most cases, the amount of iron in water from a well is more of a nuisance rather than a health risk. Most people don't like it when water tastes like metal or has a red or brown tinge. Since both iron and manganese can stain plumbing fixtures, laundry, and other items, it can ruin clothing and leave sinks and tubs looking dirty, even when they aren't. Very high levels of manganese in water can cause neurological symptoms.
Another reason that you might want to treat high iron water is that certain types of bacteria need it to survive. These bacteria can form an unpleasant yellow or brown slime in your plumbing, and often produce a bad odor. Although they are not particularly dangerous, most people prefer to get rid of these bacteria.
If you're concerned about iron or manganese in your water, it is imperative that you perform a good water analysis. This type of water testing is not just for iron and manganese, but includes a number of other contaminants, like hardness, pH, nitrate, tannin, sulfur, TDS, and more. The inter-relationships of the different competing contaminants will help in choosing the best technology to solve your specific iron, manganese, sulfur and/or arsenic problem.
Once you've had a good water analysis, US Water will be able to confidently recommend the appropriate treatment and will provide a Performance Guarantee with the system you choose. There are several different methods for removing iron, sulfur, arsenic, and manganese from the water, and most operate on the principal of oxidizing the iron to convert it from a ferrous (dissolved or soluble) to a ferric or undissolved state. Once it is converted to the ferric state, iron can be filtered out. US Water Systems has more than 220 years of experience in using iron and manganese water filters successfully all over the country. You have come to the right place if you want to solve your problem once and for all!
In instances where the iron in water is high and the pH is low (below 5.8), a Synergy Twin-Alternating Water Softener can be used to remove some iron and manganese. This method often only has a limited impact, however, especially if your pH is neutral or higher. In most cases, iron and manganese need to be oxidized to be removed. Other contaminants, like sulfur, will not be removed by a water softener. In practically every case, the Synergy is a great idea after the iron and manganese are reduced or removed by the OXi-Gen System.
Over 20 years ago, we begin experimenting with introducing air (which is 21% oxygen) into a backwashing tank of catalytic carbon based media as a way to treat iron and manganese in drinking water. We did this with a water softener valve that was modified to suck in air instead of salt brine. While we do not claim to be the first to do this, there weren't many other companies that we were aware of who were. Others have used air pumps, air injectors, and micronizers, all of which added 21% oxygen to the system.
Oxygen is an excellent oxidizer of iron, sulfur, and manganese and recently, US Water introduced the next generation in its line of oxygen systems called the inFusion Chemical-Free Iron and Sulfur Eradication System. It is built on a commercial water softener platform with a 1" high flow (up to 20 GPM) control valve that draws in oxygen from the air to oxidize the iron and sulfur. It does not use the typical manganese dioxide media, but rather uses the lighter and much more effective catalytic carbon, which acts as a catalyst between the oxygen and the iron and sulfur. So, if you have really moderate iron or manganese or sulfur in your water, this chemical free method will handle about any level thrown at it. No chemicals, no high cost of operation, and no ozone “ just clean, fresh water!
At US Water, we no longer use medias that end in lox. It is our opinion that Katalox, Pyrolox, Filox and all the rest are best installed by a local deal who hopefully lives next door and has a key to your house, because he is going to be there a lot. While these medias do work in some cases, we do not believe they are reliable and the results are unpredictable. If you have one that works¦ great! We like to be able to GUARANTEE results and the only way we can do that is with the OXi-Gen System.
Lead can be harmful to your body, but just how harmful depends on how much lead you consume, your health, and where the lead becomes stored in your body. Exposure to lead causes a variety of health effects, and affects children in particular.
Many years ago, lead was used in the construction of home water pipes and municipal underground water distribution systems. Lead solder was also often used on brass or chrome-plated brass faucets and plumbing fixtures. When these pipes or plumbing fixtures are exposed to water – especially acidic water – the lead they contain can be corroded and dissolved into the water. Lead is a known toxin and can cause neurological and physical problems, especially in young children.
In adults, high lead levels can damage the nervous and reproductive systems and the kidneys. In addition, it can cause high blood pressure and anemia. This mineral accumulates in the bones, and lead poisoning may be diagnosed from a blue line around the gums.
Lead is especially harmful to the developing brains of fetuses and young children, and to pregnant women, and interferes with the metabolism of calcium and vitamin D. High blood lead levels in children can cause consequences that may be irreversible, including learning disabilities, behavioral problems, and mental retardation. At very high levels, lead can cause convulsions, coma, and death.
Any amount of lead in water over 0.015 mg/l needs to be treated.
Unfortunately, you cannot taste or see lead in drinking water, so there is no way to know if your water is contaminated without testing. If you have an older home or have any reason at all to suspect that your water might contain lead, it needs to be analyzed by a certified laboratory, not someone giving a free analysis to sell you some type of treatment systems. At the very minimum, you should perform our Comprehensive Lab Water Test or a similar analysis.
Because the most common causes of lead in water are pipes in old buildings or older municipal underground distribution systems, replacing those pipes is the best way to prevent lead in drinking water. This is very costly, however, and may not be possible. If the source of the lead cannot be corrected, then you need to get a water treatment system that is designed to remove lead from water. The options are:
Reverse Osmosis will remove lead from drinking water
The US Water Cobalt Hyper-Safe reverse osmosis system removes the largest spectrum of contaminants of any drinking water system on the market today. The system removes more contaminants because it uses the very latest in cutting-edge technology… some of which is utilized in semiconductors. It removes lead and a lot more.
This is a professional-grade system built with the highest quality components and backed with a warranty that is up to 300% longer than our competition. The Cobalt Hyper-Safe 5-Stage RO system uses all NSF, WQA and FDA Certified components. This is the system for you if you don’t settle for just another RO system. It wastes up to 80% less water and makes water up to 75% faster than other systems.
Symptoms: Methane and other gases can be flammable (don't smoke in the shower is a joke frequently told) and explosive.
Causes: Methane occurs naturally, especially in swampy areas where it is called "marsh gas, " but homeowners in areas where "fracking" is common say that methane has tainted their water more frequently.
Health Concerns: Although methane concentrations in drinking water aren't regulated, the gas readily comes out of solution and is an asphyxiation and explosion hazard.
Action Level: Although methane concentrations in drinking water aren't regulated, the gas readily comes out of solution and is an asphyxiation and explosion hazard. The US Department of the Interior recommends mitigating methane levels in water if concentrations reach 10-28 mg/l.
A simple qualitative test for methane can be done with the use of a plastic, narrow-mouthed milk carton and a book of matches. Use the following procedure:
1. Fill the gallon container up to the bottom of the narrow neck. Place hand over the mouth of the bottle. If methane is present, it will collect in the upper portion of the container.
2. Bring a lighted match to the mouth of the bottle and quickly move hand away. The presence of methane will result in a brief wisp of blue or yellow flame. Note: It is important that a plastic container be used rather than glass because of possible breakage. This test should be performed outdoors and away from flammable materials.
The best way to remove methane is with our open air system, which also addresses many other issues.
Nitrates and nitrites are related compounds that are produced naturally through the breakdown of organic matter. Inorganic nitrates are also a common component of fertilizers. Both of these compounds can make their way into your drinking water, and high levels of nitrate in water are often caused by fertilizer runoff from farms and gardens. At high concentrations, nitrates in drinking water can be dangerous, especially to children and people who have certain enzyme deficiencies. Read on to learn more about nitrates and nitrites in water, as well as how to remove them.
Nitrates and nitrites are naturally occurring compounds that are formed when organic matter decomposes. In addition, various inorganic nitrates are widely used in fertilizers, which can then contaminate your water supply. Nitrates and nitrites are both ions that contain nitrogen and oxygen; nitrates include three oxygen atoms to nitrite's two. These compounds can also be converted one to the other, and are often grouped together when discussing their role as water contaminants. Nitrates in drinking water are colorless, odorless, and tasteless, and they cannot be detected unless water samples are laboratory tested.
Potassium and ammonium nitrate, both widely used in lawn and garden fertilizers, are the most common inorganic nitrates in water. Since most nitrogenous materials in natural waters tend to convert to nitrate, all sources of combined nitrogen are potential sources of contamination. Nitrates are very soluble and do not bind to soils, so they can easily get into groundwater. In addition, these compounds do not evaporate and often remain in water until consumed by plants or animals.
High nitrates in water have caused serious illness and sometimes death. This compound is particularly dangerous for babies, children, and adults who have a certain type of enzyme deficiency. In addition, people who have lower levels of stomach acid may be more susceptible to nitrate in drinking water. Nitrates are converted into nitrites in the body, which is why both can be dangerous.
The problem with nitrates and nitrites is that they affect how the blood carries oxygen. Nitrites can oxidize the iron in your blood, making it unable to transport oxygen. High nitrate intake can lead to methemoglobinemia and some cases of "blue baby syndrome, " an acute condition in which health deteriorates rapidly over a period of days. Symptoms include shortness of breath and blueness of the skin, headache, fatigue, and changes in mental status, and in severe cases, coma and death.
The EPA has set the maximum contaminant level of nitrates allowed in drinking water at 10 mg/L NO3-N or 45 mg/NO3. Families with children who get their water from private wells should monitor nitrate levels in water, as should people who have been diagnosed as having low levels of the methemoglobin reductase enzyme or low stomach acid.
Nitrates and nitrites can be difficult to remove from water. Unlike many chemicals, these compounds cannot be treated with standard granular activated carbon filters. Instead, a special anion resin ion exchange media specifically designed for nitrate removal needs to be used; standard anion resins may actually make the problem worse.
US Water nitrate removal cartridges effectively treat high nitrates in water by using ResinTech® SIR-100-HP resin. Its unique functionality offers 25 times greater affinity for nitrate than standard strong-based anion resins. This cartridge provides nitrate removal efficiently with low leakage, and eliminates the possibility of nitrate dumping upon exhaustion.
ResinTech® SIR-100-HP media is certified by the Water Quality Association (WQA). In fact, it's WQA Gold Seal Certified and meets NSF/ANSI 61 guidelines. This nitrate removal resin has the highest operating capacity of any nitrate selective resin. ResinTech®SIR-100-HP is uniform particle size, low-pressure drop, and has superior physical stability.
US Water nitrate cartridges are double-open end cartridges that fit standard residential and industrial housings, which means that you have the flexibility to use our cartridges in any standard size filter system. This is important because we think that you deserve the freedom to choose the best filters for you and not be tied to one proprietary system. Our cartridges are also large, so they offer up to 50% higher capacity and extended life.
To ensure consistent quality and peace of mind for your, the consumer, all drinking water media from US Water Systems is WQA Gold Seal or NSF certified. We produce quality products right here in the U.S.A.
Per- and Polyfluorinated substances are a group of man-made chemicals that persist in the environment. These chemicals have been used for decades in consumer products to make them non-stick and water resistant. They are also found in firefighting foams and are applied in many industrial processes. Unfortunately, the characteristics that make them useful is also the reason they persist in the environment and can bioaccumulate, or build up, in our bodies and the bodies of wildlife.
Yes, they are dangerous. The health risks of exposure to the chemicals include developmental effects to fetuses during pregnancy or to breastfed infants, cancer, liver effects, immune effects, thyroid effects, and more. The truth is, these are an emerging family of contaminants and researchers have not had enough time to discern the long-term effects of these contaminants.
Currently there are no enforceable federal drinking water limits for PFCs, however, that will likely change in the very near future. In May of 2016, the EPA released Lifetime Health Advisories of 0.070 microgram per liter (mg/L) (70 ng/L) for PFOA and PFOS (individually or combined) for exposure from drinking water. These advisory levels are set at concentrations which EPA is certain are protective for the most sensitive individuals against reproductive and developmental impacts with a margin of safety. The EPA has identified PFCs as an emerging contaminant because they have a pathway to enter the environment, may pose a human health or environmental risk, and do not have federal regulatory standards. In addition, individual states have begun to develop state PFC guidelines for monitoring and reducing PFCs in the environment.
Certain technologies have been found to remove PFAS from drinking water, especially Perfluorooctanoic acid (PFOA) and Perfluorooctanesulfonic acid (PFOS), which are the most studied of these chemicals. Those technologies include activated carbon adsorption and reverse osmosis membranes. At US Water Systems we always look at water problems and ask ourselves: If this were the water my family and I had, what would we do?
The fact of the matter is that we would want Reverse Osmosis to handle the PFOA or PFOS in our water, but pre-treatment is vitally important. Most of these PFOA and PFOS problems are on well water, which may have other problems, such as iron, manganese, sulfur, hardness, nitrate, low pH, and other issues. It™s important to have a Good Water Analysis such as THIS.
Treating surface water " which includes all water that is held on the top of the ground, such as lake water, pond water, rain water, and water from any reservoir " is always challenging because it varies from area-to-area and season-to-season. As a result, you need a carefully designed system that is made for lake and pond water treatment. Turn to the Certified Water Specialists at US Water Systems for help!
Due to the high cost of drinking water and the fact that water is not always easily available from other sources, more and more homes, industries, and municipalities use treated surface water. Because it's open to the air and a range of possible contaminants, surface and pond water treatment normally needs to be performed before the water has the quality required to make it safe to drink. Surface water typically contains a high suspended solids content, bacteria, algae, and organic matter, creating a bad taste and odor. In some areas, like river estuaries, this water can be brackish, reaching up to 8, 000 mg/L of salts, and that is an issue that requires a whole different set of surface water treatment equipment.
The US EPA has something called the Surface Water Treatment Rule, which seeks to prevent waterborne diseases caused by viruses, the Legionella bacteria, and Giardia lamblia, a parasite. These disease-causing microbes can be found in varying concentrations in most surface waters. The rule requires a surface water treatment process that includes filtering and disinfecting the water to reduce unsafe levels of these pathogens.
The best method for surface water treatment will depend on many factors, including where you live and the time of year. It's important to have your water tested so you know what's actually in it. At US Water Systems, we offer a number of specially designed lake and pond water treatment systems that are made for home use. These systems include the following components:
1. Sediment backwashing filter
2. Chlorine injection system
3. A chlorine storage tank
4. A fiberglass retention tank
5. Granular activated coconut shell carbon backwashing filter
6. 5 micron and 1 micron filters
7. Ultraviolet or Silecte disinfection
Radiation can enter the water supply due to both natural and man-made sources. Small traces of radioactivity are found in nearly all drinking water, but many people are concerned about the potential dangers of potential pollutants from nuclear energy plants, laboratories, and other sources. Read on to learn more about radioactive water, how much is considered "acceptable" in water, and how to remove radioactive water pollution.
Radioactivity, or radioactive decay, is a form of energy that's released by the decay of the nucleus of an unstable atom. We are exposed to lots of forms of radiation in our daily lives – the light from the sun, for example, is a form of radiation. When we talk about radioactivity, however, we tend to think about things like X-rays, atomic bombs, and nuclear energy. Each of these examples does involve radioactive elements, but so do certain types of rocks naturally found in the soil.
When scientists talk about radioactive decay, they usually focus on alpha, beta, and gamma radiation, although there are additional types of emissions. Alpha particles are typically not considered dangerous unless they are swallowed or inhaled – in which case, they are extremely harmful. Beta radiation can penetrate living tissue and can cause spontaneous mutations in DNA. Gamma rays can cause damage at the cellular level. X-rays, which many people are familiar with, are a type of electromagnetic radiation that typically has a wavelength longer than gamma rays, although there is actually no clear consensus distinguishing these two types of radiation.
It's actually very common to find low levels of radioactive isotopes in drinking water supplies, and it's typically nothing to be concerned about. There have been cases, however, in which the level of radioactivity in water has been found to be higher than expected. Certain rock types naturally contain radioactive elements referred to as NORM (Naturally Occurring Radioactive Materials). When a source of drinking water comes in contact with NORM-bearing rocks, radionuclides may accumulate in the water to levels of concern. The predominant radionuclides found in water include radium (and its decay products), thorium (and its decay products), and uranium (and its decay products).
There is no way to know if your water contains any radionuclides without testing it. Municipal water supplies are regularly tested for these radioactive substances, but if you have a private well, you should be testing the water regularly for a range of possible contaminants.
The U.S. Environmental Protection Agency (EPA) set legal limits called "maximum contaminant levels" or MCLs for many different possible water contaminants, including radionuclides. For alpha particles, the MCL is 15 picocuries per Liter (pCi/L); for beta particles, it's 4 millirems per year. The EPA also sets limits for radium 226 and radium 228 – two isotopes of radium, a highly radioactive element – at 5 pCi/L, and uranium – which is used in nuclear power plants and nuclear weapons, among other things – at 30 micrograms per liter (ug/L).
It's important to note that, despite these legal limits, the maximum contaminant level goal (MCLG) – the level below which there is no known health risk – is actually zero for all radionuclides. In other words, there is no known level at which the amount of these radioactive substances in water is considered safe.
Cancer is considered by most people to be the main health effect from radiation exposure. When exposed to ionizing radiation, cells can be seriously damaged at the cellular or molecular level. This may cause mutations in the DNA or cause the uncontrolled growth of cells, which is the definition of cancer. The body can sometimes repair mutations in the DNA, but not always – and additional problems can sometimes develop as the body tries to fix itself.
If you are concerned about the levels of radioactivity in your water, then you will need to put a treatment plan into place. Unfortunately, there is no simple answer for removing radiation from the water. In many cases, a combination of treatment methods, including carbon filtration, ion-exchange water softening, and reverse osmosis, is most effective.
Radon is a dangerous, naturally occurring gas that can cause lung cancer. Because it's produced in the soil, this radioactive gas can sometimes be found in the air in homes and other buildings, as well as drinking water from underground sources, like that which comes from private wells. If you get your water from a well, it's important to have it tested regularly for radon and other possible contaminants. There are a number of ways to remove the radon in water, and the Certified Water Specialists at US Water Systems can help.
Radon is a radioactive gas that has no color, odor, or taste. It is found naturally in the soil in some places, and comes from the breakdown of uranium found naturally in the ground. As this element breaks down, radon gas forms and can easily seep into the air in homes, offices, schools, and any other type of building. In addition, radon gas can dissolve into underground water sources, such as wells, and accumulate there. The gas is released when you use the water, whether for showering, washing dishes, or some other purpose, although it can also be consumed when you drink it.
Yes, radon is dangerous. Radon gas in the air has been directly linked to lung cancer, and about 20, 000 deaths a year in the U.S. are caused by breathing it in. Radon in drinking water that is ingested is believed to increase the risk of several different types of cancer, including stomach cancer. The EPA estimates that about 168 deaths a year can be attributed to radon in water.
One of the reasons that radon in water is so dangerous is that the gas decays into radioactive particles that can get trapped in your lungs when you breathe it. As they break down further, these particles release small bursts of energy that can damage lung tissue and increase your chances of developing lung cancer. While not everyone exposed to high levels of radon in the air will develop lung cancer, it is the second leading cause of this type of cancer, behind smoking.
No level of radon in water is considered safe. However, there is currently no federal drinking water standard for radon. The EPA has proposed requirements for radon levels no higher than 4, 000 pCi/L, in states where actions are being taken to mitigate radon in indoor air, and 300 pCi/L in those states without such programs. Although radon water is dangerous, it's not as big of a risk factor as radon in the air.
If you get your water from an underground source, like a private well, you should test the water for radon and implement a radon water mitigation system if needed to reduce your exposure.
The best way to reduce radon levels in water is through aeration, which means exposing the water to air so that the gas can escape. It's important for an aeration radon water mitigation system to vent the gas into the atmosphere outside of the home, where it is no longer a danger. Aerated water should then be treated with carbon filtration. Some people try to use just carbon as a radon water filter, but unless the amount of radon in the water is extremely low, carbon filtration by itself is not completely effective.
If you have cloudy water or water that tastes gritty, you probably have a problem with sand, silt, or sediment. While not usually dangerous, water that seems like it's full of dirt or other particles can be unpalatable and just generally not good to drink. US Water Systems offers a variety of sedimentation water treatment options, although finding the right treatment can take a little trial and error.
When you get your water from a well or surface water source, you may find that there are particles of sand and silt that make their way into your plumbing system. Often, you'll notice cloudy water, particles floating in your in water or sinking to the bottom, plugged screens and faucets, and damage to appliances and washing machines caused by particles. The cloudiness or haziness is called "turbidity, " and it's caused by individual particles that are generally invisible to the naked eye. All of these pollutants can be removed using special filters for sedimentation water treatment.
Typically, you'll find sand, silt, and sediment in water when you get your water from a well that is in a sandy area or from a surface water source that may contain a great deal of silt. Turbidity can be caused by soil erosion, waste discharge, storm water runoff, eroding stream banks, bottom feeding fish, and algae growth.
Generally speaking, there are likely no real health concerns related to drinking water that contains sand or sediment (other than grit between your teeth). Most people don't like drinking gritty water, however, and it can cause problems in faucets, showers, and appliances where the sediment collects and causes blockages.
The best way to deal with sedimentation in water treatment is to use a physical water filter. These filters are measured in microns, which tells you what size particles the filter can trap. You can find filters with micron ratings as large as 50 microns (about the size of the average human hair) down to 0.35 microns and smaller. US Water Systems offers a range of sediment filters for your home, as well as a wide range of replacement filters for sediment water treatment, including pleated and spun polypropylene.
When buying a sediment water treatment filter, you often need to choose a filter with a small enough micron range to trap a majority of particles, but not so small that you have to change the filter with too much frequency. If you have large particles in your water, for example, you'd want to start with a 50 or 20 micron filter, which would take care of those larger particles. If you put in a 5 micron filter alone, it would likely clog up very quickly. The truth, however, is that removing sand, silt, sediment, or turbidity is an inexact science “ you simply have to try different micron sizes and types of filters in order to remove all of these contaminant efficiently. Call the Certified Water Specialists at US Water Systems to get started with your sediment water treatment.
Does your water smell like rotten eggs? Does it leave a white, brown, black, or gray slime in your pipes and fixtures? Water that's high in sulfur often smells bad and leaves stains behind. Learn more about sulfur water problems from the water professionals at US Water Systems.
If you have sulfur water problems, you probably know it – even if you don't know the cause. Many people say that their water has a distinct "rotten egg" odor, which is the familiar sulfur smell. Technically, what you're smelling is hydrogen sulfide (H2S), a colorless gas that's dissolved in the water. You'll also likely see a white, grey, reddish brown, or black slime in your plumbing system or well; this can be caused by sulfur-oxidizing bacteria. This slime can promote the growth of other bacteria, such as iron bacteria, as well as causing black stains on silverware and plumbing fixtures, and even corrode pipes and other metal components.
Although hydrogen sulfide is a poisonous gas, the levels this type of sulfur in water are more of a nuisance than a health threat. When your water smells like sulfur, turning on the hot water for a shower or to wash dishes can release a burst of foul-smelling odor. Your water may also taste bitter or like rotten eggs, making it unpleasant to drink, and it can also affect the taste of foods cooked in it.
Some individuals find that a bigger worry about sulfur water is how it affects their plumbing systems. Hydrogen sulfide is corrosive, so it may discolor silverware and faucets, especially those containing copper, brass, steel, or iron. The slime caused by sulfur water can clog up your pipes and leave nasty stains in toilets and other fixtures.
Sulfur is considered a secondary or aesthetic contaminant. The present recommended limit for sulfur in water, 0.3 mg/l (ppm), is based on taste and appearance rather than on any detrimental health effect. Private water supplies are not subject to the rules, but the guidelines can be used to evaluate water quality. In rare cases, the presence of hydrogen sulfide can indicate that your water has been contaminated by sewage, so it's important to test your water regularly.
In many cases, the sulfur in water comes from the rocks and soil that groundwater moves through before it gets to your well. Sulfur is a naturally-occurring mineral that can easily be dissolved into water. In addition, certain sulfur bacteria can be in the groundwater, in the well, or in the water distribution system where they convert sulfates into hydrogen sulfide. This gas is also found naturally in groundwater in some places.
If you have detected a sulfur smell in your water, it's a good idea to have a good water analysis performed. This water test doesn't just detect sulfur in water, but can also detect a number of other contaminants, including hardness, pH, manganese, iron, and total dissolved solids (TDS). The inter-relationships of the different contaminates will help you to determine the best technology to solve your problem.
With a detailed laboratory analysis, US Water Systems will be able to confidently recommend the appropriate treatment and will provide a Performance Guarantee with the system. We stand behind our products with a money-back guarantee when we have a good water analysis of the water we are treating. If you purchase the recommended solution, you will receive a credit for the cost of your water analysis.
There are many ways to remove sulfur from water, and most operate on the principal of oxidizing the sulfur to change it from a gas to a solid or undissolved state. Once in the solid state, you can simply filter this contaminant out. Oxidizing filters are the most common method of sulfur water removal, but other common processes such as ozone, aeration, chlorine, or peroxide injection may be used to boost the oxidizing properties of the water being treated.
Special backwashing filters are the most widely used system for removing sulfur in water. These filters contain a special media, listed below, to turn the dissolved sulfur into solid particles and filter them out. It's important to note that The pH of the water plays an important role in how quickly sulfur in gas form converts to a solid state. The higher the pH, the faster sulfur will convert to the solid state that can then be filtered. This is a good thing for your equipment, with the exception of water softener – in these systems, the oxidized sulfur plugs the exchange sites and fouls the resin.
When using a sulfur filter, a pH above 6.5 is an absolute necessity, and in reality a pH above 7.0 is what is really needed. A pH of 8.0 to 8.5 greatly enhances the chance of a successful application. If you have acid water, you'll need to address this before you can remove the sulfur smell. If it is necessary to increase the pH level, a chemical feed of sodium carbonate or soda ash is preferred over a filter filled with calcium carbonate (calcite) or magnesium oxide (Corsex), as the filter method may foul quickly. Low pH levels are the chief reason for unsatisfactory results when using an oxidizing filter.
What follows is a partial list of medias used in sulfur water filtration. We do not attempt to address all medias, especially ones which are dubious in design or outdated.
1. Birm - Birm has the ability to remove sulfur and manganese, but it has no effect on hydrogen sulfide. This media uses dissolved oxygen as a catalyst and may require some type of pre-oxidation in cases where the dissolved oxygen content is too low to affect a maximum sulfur removal result. Birm is 0.1% manganese dioxide and is fairly lightweight, which allows for proper backwashing. US Water does not sell a birm filter, as there are simply better methods that are more predictable and effective for removing sulfur.
2. Greensand Plus - Greensand is one of the oldest proven oxidation technologies. Potassium permanganate produces manganese dioxide on the surface of the Greensand and, once the water comes in contact with it, any sulfur is immediately oxidized. The sulfur can be filtered and then cleaned away in the backwash cycle. Greensand is only effective with low levels of hydrogen sulfide and manganese, however, and US Water chooses not to recommend a Greensand Plus system.
3. KDF-85 - KDF-85 is a redox media, which means that it requires dissolved oxygen to be effective. It is made up of two metals – 85% copper and 15% zinc. These two dissimilar metals create a small electrical field in the bed that will not allow bacterial growth in the media. This property earns redox the distinction of being effective on bacterial sulfur without the use of chlorine injection, and being rated as bacteriostatic. While it is effective for the removal of sulfur and hydrogen sulfide, and is able to reduce chlorine and heavy metals such as lead and mercury, KDF-85 is not effective with manganese. The biggest drawback for the KDF-85 media is its weight. Being almost twice as heavy as other medias, KDF-85 requires more than twice the backwash rate of other minerals and can cement together in the tank.
4. Manganese Dioxide - Filox - Manganese dioxide, often called Filox or Pyrolox, is a naturally mined ore with the ability to remove sulfur, manganese, and hydrogen sulfide. Its hydrogen sulfide removal capability exceeds that of either Greensand or Birm and requires no chemicals to regenerate. Filox does, however, require adequate amounts of dissolved oxygen in the water as a catalyst. If the dissolved oxygen level is not sufficient, this media may require some type of pre-oxidation to achieve its maximum ability, such as injection of chlorine with a chemical feed pump. You should never use Filox or Pyrolox unless you have exceptionally high water pressure and volume.
At US Water Systems, we believe that the above methods of sulfur removal are less than satisfactory in most cases. Below, we list several additional methods of oxidation and filtration, including our recommended system type.
US Water has pioneered the use of hydrogen peroxide in water treatment for the eradication of sulfur and manganese for over 20 years. It can truly be called an eradication system because it completely removes sulfur, iron, and manganese. Properly sized, a hydrogen peroxide system is a very effective method for removing sulfur, iron, rust, hydrogen sulfide, and manganese and the rotten-egg sulfur smell from your water supply.
Hydrogen peroxide is not a hazardous chemical – to the contrary, hydrogen peroxide or H2O2, is composed of the elements of water: hydrogen and oxygen. There is nothing foreign or chemical added to the water supply. Unlike chlorine, hydrogen peroxide requires no contact time and the reaction or oxidation of sulfur, iron, rust, manganese, and hydrogen sulfide is immediate. A quality hydrogen peroxide system is the answer to practically any sulfur water problem. With hydrogen peroxide, you can always predict for a certainty that it will work, even with excessive amounts of sulfur (or iron).
Ozone is a powerful oxidizer and, when used properly, it can be effective on large amounts of sulfur. Ozone is injected into the water via a contact vessel as a pre-treatment to filtration. A properly sized ozone generator and proper system design is the key to success. Due to ozone's expense, it is usually applied on sulfur levels higher than other methods of filtration can handle effectively. Each system is custom designed for the application, and ozone systems typically cost three or four times more than other methods – it does have a very minimal operating cost, however.
Chlorine is a powerful oxidizer, so it's not uncommon to use 5% to 10% chlorine to treat high sulfur water. Chlorination requires a contact tank, however, which should have a 20 minute supply of water at peak flow. For instance, if the peak flow is 10 gallons per minute, then a 200 gallon contact tank would be needed. Many chlorination systems are undersized in respect to the contact tank, and meet with mixed results. After the injection of the chlorine and flow into the contact tank, a backwashing carbon filter is needed to remove the precipitated sulfur and residual chlorine. Chlorine works well as a disinfectant, but it is not a good oxidizer for this purpose, and it can only remove a small amounts of sulfur. At US Water, we do not recommend chlorination for the removal of sulfur.
Air injection has become a popular way of oxidizing iron, manganese, and sulfur in water. A variety of methods are used to inject air into the water supply, including air pumps and compressors, which are highly problematic (not to mention noisy). Of course, air has a lot of oxygen, which is an excellent oxidizer of sulfur (as well as iron and manganese). Many companies are now using a water softener control valve to pull in air instead of drawing brine, introducing a head of air into the tank. The oxygen oxidizes the sulfur and iron, and it is filtered out by the special catalytic media in the filter. However, the downside to using air injection to treat sulfur water is that the injectors often plug and fail to operate.
Found in many species of plants and often released into the soil and water when vegetation decomposes, tannins in water can be difficult to remove. These biomolecules give water a yellow or brownish tint and often make it taste bitter, but they are not a health risk. If you have tannins in your water, read on to learn more about this contaminant and ways to filter and treat it from the Certified Water Specialists at US Water Systems.
If your water looks more like tea than the clean, clear liquid that it should, you may have a problem with tannin in the water. The distinct brownish color of a nice cup of hot Earl Grey tea or a glass of cold iced tea comes from tannin, a biomolecule found in plants – including tea leaves. While this color and its accompanying slightly bitter, astringent taste may taste great in tea, it isn't very desirable in water. The color makes water look dirty and can stain porcelain fixtures and laundry.
Tannins are found in many types of vegetation, including tea, berries, nuts, and many types of trees. When those plants decompose in the soil, they easily leach into the water that flows through them, making their way into surface water supplies and shallow wells. Along with the tannins are humic acid and fulvic acid, related "humic" substances – substances that are produced by decaying organic matter – which can enter the water supply. All of these substances have a similar impact on the water, changing the color and making it taste and smell bitter. Exactly which humic acids and tannins in water are causing the problem will vary depending on the plant life in a given area.
Tannins in water are not a health concern. Many of the foods that we eat every day contain various types of tannins, and they are in fact added to a number of beverages for their color and taste. In water, however, they are very undesirable.
Because there are a number of different tannins and types of humic acids, they can be very difficult to remove from water. Just because one treatment method for tannins in water works well in one location, that doesn't mean it will be effective a few miles away, where the vegetation may be different. Historically, styrene-based macroporous anion resin has been used to treat tannin water, but it doesn't always work. Acrylic-based resins have been used more recently and have produced better results. They are made with a macroporous structure that allows them to be regenerated more effectively.
In most cases, water treatment experts recommended that tannin water be treated by a water softener before being processed by a tannin removal system. The softener uses a cation media to removes hardness minerals and some metals, both of which can have a negative impact on the anion resin used to remove tannins. The water softener uses an ion-exchange resin that attracts positively charged particles, so it won't have any impact on the tannins in the water.
Tannins have a slight negative charge, which is why they can be treated with anion resins, which attract negatively charged particles. In this specialty resin, the tannin ions are exchanged for chloride ions. Since the resin can't really distinguish between tannins in water and any other type of negatively charged particle, it will also remove these additional ions. This typically means that alkaline ions are removed, which can cause a corresponding decrease in the pH of the water. Once the resins capacity for these ions has been reached, the pH will go back to its original level. Nitrates are also frequently removed by this type of resin.
This anion resin is typically regenerated (meaning that the accumulated tannins are removed and new chloride ions are made available for the ion-exchange process) with salt, and the resin will generally be brined at 10 lbs per cubic foot. Most importantly, this regeneration should be performed every two to three days, which will reduce the likelihood of organic fouling. Tannins tend to migrate into the inner matrix of the anion resin. Once this occurs, it is very difficult to regenerate the tannins from the resin.
In many tanning treatment systems, the tannin resin is mixed with softening resin. This reduces the amount of space required by the equipment and lowers the cost of the equipment. This type of design is not ideal, however, since the mixing of the media can cause problems. US Water does not recommend that cation and anion resin be mixed together in the same tank, and recommends softening first, followed by a tannin removal system.
One drawback to treating tannins in water with anion resins is the potential for the system to develop a fishy odor. This is caused by trimethylamine (TMA), which is an organic compound used to make the resin. Under high pH conditions, the TMA (even in small concentrations) can produce this unpleasant smell, although it should dissipate relatively quickly. When the resin is made with the proper post-treatment, it will generally lose its odor within a regeneration or two. It should be noted that a macroporous anion resin will generally clean-up faster and easier than gel type anion resins. If your water naturally has a high pH (greater than 8), it's more likely to release a fish odor, and there's really no good way to prevent this. Putting the resin through several regenerations and exhaustion cycles should reduce the smell.
Probably the worst case scenario will occur when there is both high pH and chlorine. As chlorine degrades the tannin resin, the combination of by-products and high pH can create a smell that may never completely go away. It can also be a problem with water treated with chloramines.
While tannin removal anion exchange resins are a popular way of removing tannin from your water supply, you need to realize that a tannin anion exchange system can use several hundred of dollars a year in salt and waste up to 80 gallons of regenerating water every other day. You may need to replace the resin in 5 or 6 years. We think there is a better way.
Recently, a technology called charged membrane filtration (CMF) has proven to be highly effective at removing tannin from water supplies. The US Water Disruptor system is truly "disruptive technology, " that is ready to displace the established technology and shake up the industry. The Disruptor Charged Membrane Filter System can remove the following contaminants:
Charged membrane filtration is manufactured with Nano alumina fibers that have a zeta potential of 51 millivolts. A CMF cartridge retains bacteria, virus, cryptosporidium oocysts and even tannin because of this strong zeta potential. The electroabsorbative technology for water purification CMF media is engineered this 51 millivolt charge cover the entire volume and depth of the media.
Unlike mechanical filters that rely on pore size, the CMF technology literally secures the contaminant by absorbing it in a very real way. This allows for virtually zero pressure drop and high flow rates. If you compare the Disruptor CMF to ultrafiltration membranes, you will find dramatically higher flow rates with less pressure drop. The filters also have a long life and are easily replaceable.
The CMF media is manufactured from a naturally occurring element called boehmite, which has no known health side effects. In fact, boehmite has long been used as an additive to food products and digestive analgesics. Additionally, it has passed testing for NSF/ANSI Standard 42 and 61 for potable water and USP Class VI testing and endotoxin testing.
Overall, US Water recommends CMF over anion exchange softening due to cost and performance.
Oxidizing agents such as chlorine and ozone are sometimes also effective at breaking down tannins in water. A simple jar test will show the concentration and retention time required to oxidize the tannins. An activated carbon unit following the retention tank will remove the oxidant and adsorb any additional organic compounds in the water. It should be noted that some activated carbons alone may not have a significant amount of capacity for tannins, so consult your carbon manufacturer for the appropriate type of carbon. Reverse osmosis is another effective method of removing tannins.
A baghouse, also known as a baghouse filter, bag filter, or fabric filter is an air pollution control device and dust collector that removes particulates or gas released from commercial processes out of the air.
In mechanical-shaker baghouses, tubular filter bags are fastened onto a cell plate at the bottom of the baghouse and suspended from horizontal beams at the top. Dirty gas enters the bottom of the baghouse and passes through the filter, and the dust collects on the inside surface of the bags.
Cleaning a mechanical-shaker baghouse is accomplished by shaking the top horizontal bar from which the bags are suspended. Vibration produced by a motor-driven shaft and cam creates waves in the bags to shake off the dust cake.
Shaker baghouses range in size from small, handshaker devices to large, compartmentalized units. They can operate intermittently or continuously. Intermittent units can be used when processes operate on a batch basis; when a batch is completed, the baghouse can be cleaned. Continuous processes use compartmentalized baghouses; when one compartment is being cleaned, the airflow can be diverted to other compartments.
In shaker baghouses, there must be no positive pressure inside the bags during the shake cycle. Pressures as low as 5 pascals (0.00073 psi) can interfere with cleaning.
The air-to-cloth ratio for shaker baghouses is relatively low, hence the space requirements are quite high. However, because of the simplicity of design, they are popular in the minerals processing industry.
In reverse-air baghouses, the bags are fastened onto a cell plate at the bottom of the baghouse and suspended from an adjustable hanger frame at the top. Dirty gas flow normally enters the baghouse and passes through the bag from the inside, and the dust collects on the inside of the bags.
Reverse-air baghouses are compartmentalized to allow continuous operation. Before a cleaning cycle begins, filtration is stopped in the compartment to be cleaned. Bags are cleaned by injecting clean air into the dust collector in a reverse direction, which pressurizes the compartment. The pressure makes the bags collapse partially, causing the dust cake to crack and fall into the hopper below. At the end of the cleaning cycle, reverse airflow is discontinued, and the compartment is returned to the main stream.
The flow of the dirty gas helps maintain the shape of the bag. However, to prevent total collapse and fabric chafing during the cleaning cycle, rigid rings are sewn into the bags at intervals.
Space requirements for a reverse-air baghouse are comparable to those of a shaker baghouse; however, maintenance needs are somewhat greater.
In reverse pulse-jet baghouses, individual bags are supported by a metal cage (filter cage), which is fastened onto a cell plate at the top of the baghouse. Dirty gas enters from the bottom of the baghouse and flows from outside to inside the bags. The metal cage prevents collapse of the bag.
Bags are cleaned by a short burst of compressed air injected through a common manifold over a row of bags. The compressed air is accelerated by a venturi nozzle mounted at the reverse-jet baghouse top of the bag. Since the duration of the compressed-air burst is short (about 0.1 seconds), it acts as a rapidly moving air bubble, traveling through the entire length of the bag and causing the bag surfaces to flex. This flexing of the bags breaks the dust cake, and the dislodged dust falls into a storage hopper below.
Reverse pulse-jet dust collectors can be operated continuously and cleaned without interruption of flow because the burst of compressed air is very small compared with the total volume of dusty air through the collector. On account of this continuous-cleaning feature, reverse-jet dust collectors are usually not compartmentalized.
The short cleaning cycle of reverse-jet collectors reduces recirculation and redeposit of dust. These collectors provide more complete cleaning and reconditioning of bags than shaker or reverse-air cleaning methods. Also, the continuous-cleaning feature allows them to operate at higher air-to-cloth ratios, so the space requirements are lower.
A digital sequential timer turns on the solenoid valve at set intervals to inject air into the blow pipe and clean the filters.
High collection efficiency
Strong woven bags
Low air-to-cloth ratio (1.5 to 2 ft/min)
Restricted to low temperatures
Larger space required
Larger number of filter bags required
Operators must enter baghouse to replace bags which creates potential for toxic dust exposure
Poor cleaning efficiency if positive pressure present
High collection efficiency
Preferred for high temperatures
Low air-to-cloth ratio (1 to 2 ft/min)
Unable to remove residual dust buildup
Clean (output) air must be filtered
Operators must enter baghouse to replace bags which creates potential for toxic dust exposure
High collection efficiency
High air-to-cloth ratio (6 to 10 ft/min)
Aggressive cleaning action
Strong woven bags
Lower bag wear
Lower power consumption
Smaller space required
Bag changing without entering baghouse
Dry compressed air required
Restricted to low to medium temperatures
Unable to function with high humidity gases
Two basic sequences are used for bag cleaning: intermittent (or periodic) cleaning and continuous cleaning.
Intermittently cleaned baghouses consist of a number of compartments or sections. One compartment at a time is removed from service and cleaned on a regular rotational basis. The dirty gas stream is diverted from the compartment being cleaned to the other compartments in the baghouse, so it is not necessary to shut down the process. Occasionally, the baghouse is very small and consists of a single compartment. The flow of dirty air into these baghouses is stopped during bag cleaning. These small, single-compartment baghouses are used on batch processes that can be shut down for bag cleaning.
Continuously cleaned baghouses are fully automatic and can constantly remain on-line for filtering. The filtering process is momentarily interrupted by a blast of compressed air that cleans the bag, called pulse-jet cleaning. In continuous cleaning, a row of bags is always being cleaned somewhere in the baghouse. The advantage of continuous cleaning is that it is not necessary to take the baghouse or a compartment out of service for bag cleaning. Small continuously cleaned baghouses only have one compartment and are cleaned by pulse-jet cleaning described in detail later in this lesson. Large continuous cleaning baghouses are built with compartments to help prevent total baghouse shutdown for bag maintenance and failures to the compressed air cleaning system or hopper conveyers. This allows the operator to take one compartment off-line to perform necessary maintenance.
Baghouse performance is dependent upon inlet and outlet gas temperature, pressure drop, opacity, and gas velocity. The chemical composition, moisture, acid dew point, and particle loading and size distribution of the gas stream are essential factors as well.
Gas temperature – Fabrics are designed to operate within a certain temperature range. Fluctuation outside of these limits, even for a small period of time, can weaken, damage, or ruin the bags.
Pressure drop – Baghouses operate most effectively within a certain pressure drop range. This spectrum is based on a specific gas volumetric flow rate.
Opacity – Opacity measures the quantity of light scattering that occurs as a result of the particles in a gas stream. Opacity is not an exact measurement of the concentration of particles; however, it is a good indicator of the amount of dust leaving the baghouse.
Gas volumetric flow rate – Baghouses are created to accommodate a range of gas flows. An increase in gas flow rates causes an increase in operating pressure drop and air-to-cloth ratio. These increases put more mechanical strain on the baghouses, resulting in more frequent cleanings and high particle velocity, two factors that shorten bag life.
Fabric filter bags are oval or round tubes, typically 15–30 feet (4.6–9.1 m) long and 5 to 12 inches (130 to 300 mm) in diameter, made of woven or felted material. Depending on chemical and/or moisture content of the gas stream, its temperature, and other conditions, bags may be constructed out of cotton, nylon, polyester, fiberglass or other materials.
Nonwoven materials are either felted or membrane. Nonwoven materials are attached to a woven backing (scrim). Felted filters contain randomly placed fibers supported by a woven backing material (scrim). In a membrane filter, a thin, porous membrane is bound to the scrim. High energy cleaning techniques such as pulse jet require felted fabrics.
Woven filters have a definite repeated pattern. Low energy cleaning methods such as shaking or reverse air allow for woven filters. Various weaving patterns such as plain weave, twill weave, or sateen weave, increase or decrease the amount of space between individual fibers. The size of the space affects the strength and permeability of the fabric. A tighter weave corresponds with low permeability and, therefore, more efficient capture of fine particles.
Reverse air bags have anti-collapse rings sewn into them to prevent pancaking when cleaning energy is applied. Pulse jet filter bags are supported by a metal cage, which keeps the fabric taut. To lengthen the life of filter bags, a thin layer of PTFE (teflon) membrane may be adhered to the filtering side of the fabric, keeping dust particles from becoming embedded in the filter media fibers.
Some baghouses use pleated cartridge filters, similar to what is found in home air filtration systems