What is water purification?

Water purification generally means freeing water from any kind of impurity it contains, such as contaminants or micro organisms. Water purification is not a very one-sided process; the purification process contains many steps. The steps that need to be progressed depend on the kind of impurities that are found in the water. This can differ very much for different types of water.

In which ways is polluted water treated?

Settling
Before the purification process begins some contaminants, such as oil, can be settled in a settling tank. They can then be removed easily, after they have reached the bottom of the tank.
Removal of dangerous micro-organisms
Often polluted water has to be freed from microorganisms. The water is than disinfected, usually by means of chlorination.
Removal of dissolved solids
Micro-organisms are not only a threat to water; they can also be an advantage when it comes to water purification processes. They can convert harmful contaminants to harmless substances. This biological purification process usually takes a long time and it is only used for water that is polluted with contaminants that the microorganisms, usually bacteria, can convert.
Physical/ chemical techniques
when treatment by microorganisms is not an option we often use different treatment techniques, called physical/ chemical treatment techniques. Chemical treatment often deals with the addition of certain chemicals, in order to make sure that the contaminants change structure and can then be removed more easily. Fertilizers such as nitrates are removed this way. Removal of contaminants can also be done through more difficult specific chemical processes. It takes a lot of education to fully understand these purification steps. Physical treatment usually deals with purification steps such as filtration.

How can bacteria be removed from water?

Bacteria and other microorganisms are removed from water through disinfection. This means that certain substances are added to kill the bacteria, these are called biocides. Sometimes disinfection can also be done with UV-light.

What is aerobic water treatment?

When bacteria are used for water purification there are two sorts of transfer; one of these is aerobic transfer. This means, that bacteria that are oxygen dependent are converting the contaminants in the water. Aerobic bacteria can only convert compounds when plenty of oxygen is present, because they need it to perform any kind of chemical conversion. Usually the products they convert the contaminants to are carbon dioxide and water.

What is anaerobic water treatment?

When bacteria are used for water purification there are two sorts of conversion; one of these is anaerobic transfer. This means, that bacteria that are NOT oxygen dependent are converting the contaminants in the water. Anaerobic bacteria can only convert when oxygen levels are low, because they use other sorts of substances to perform chemical conversion. Anaerobic bacteria do not just develop carbon dioxide and water during conversion, but also methane gas. This can be used to keep the machinery that supports the purification going. The anaerobic conversion of a substance requires more steps than aerobic conversion, but the final result is often less satisfactory. After anaerobic conversion usually aerobic bacteria (bacteria that do use oxygen) still need to finish the process, because the water is not clean enough yet.

How are fertilizers removed from water?

Fertilizers such as phosphate are removed through addition of another chemical, usually iron. The substances than become solid precipitates, that can be filtered from the water. The removal of ammonium and nitrates is a little bit more complicated; it is a purification process that takes both aerobic and anaerobic conversion to remove them. In the aerobic conversion stage there are two bacterial species involved. Nitrosomonas bacteria that convert ammonia to nitrite and Nitrobacter bacteria that convert nitrite to nitrate after that. Although nitrate does not represent a direct health threat to most fish, high levels are still undesirable. Apart from encouraging abnormal extensive algal growth, it is now believed that high nitrate levels are implicated in some fish diseases. This means that the process cannot be stopped here. The anaerobic bacteria take over; they convert nitrate to atmospheric nitrogen gas. This process only occurs in the absence of oxygen. The first stage is the reverse of the nitrification process, it converts nitrate back to nitrite. The second stage of denitrification converts nitrite to nitrogen gas (N2). This gas can be freely released into the atmosphere without causing environmental damage.

How is drinking water purified?

Treating water to make it suitable to drink is much like wastewater treatment. In areas that depend on surface water it is usually stored in a reservoir for several days, in order to improve clarity and taste by allowing more oxygen from the air to dissolve in it and allowing suspended matter to settle out. The water is then pumped to a purification plant through pipelines, where it is treated, so that is will meet government treatment standards. Usually the water runs through sand filters first and sometimes through activated charcoal, before it is disinfected. Disinfection can be done by bacteria or by means of adding substances to remove contaminants from the water. The number of purification steps that are taken depend on the quality of the water that enters the purification plant. In areas with very pure sources of groundwater little treatment is needed.

What is water softening?

When water contains a significant amount of calcium and magnesium, it is called hard water. Hard water is known to clog pipes and to complicate soap and detergent dissolving in water. Water softening is a technique that serves the removal of the ions that cause the water to be hard, in most cases calcium and magnesium ions. Iron ions may also be removed during softening. The best way to soften water is to use a water softener unit and connect it directly to the water supply.

What is a water softener?

A water softener is a unit that is used to soften water, by removing the minerals that cause the water to be hard.

Why is water softening applied?

Water softening is an important process, because the hardness of water in households and companies is reduced during this process. When water is hard, it can clog pipes and soap will dissolve in it less easily. Water softening can prevent these negative effects. Hard water causes a higher risk of lime scale deposits in household water systems. Due to this lime scale build-up, pipes are blocked and the efficiency of hot boilers and tanks is reduced. This increases the cost of domestic water heating by about fifteen to twenty percent. Another negative effect of lime scale is that it has damaging effects on household machinery, such as laundry machines. Water softening means expanding the life span of household machine, such as laundry machines, and the life span of pipelines. It also contributes to the improved working, and longer lifespan of solar heating systems, air conditioning units and many other water-based applications.

What does a water softener do?

Water softeners are specific ion exchangers that are designed to remove ions, which are positively charged. Softeners mainly remove calcium (Ca2+) and magnesium (Mg2+) ions. Calcium and magnesium are often referred to as ‘hardness minerals’. Softeners are sometimes even applied to remove iron. The softening devices are able to remove up to five milligrams per litre (5 mg/L) of dissolved iron. Softeners can operate automatic, semi-automatic, or manual. Each type is rated on the amount of hardness it can remove before regeneration is necessary. A water softener collects hardness minerals within its conditioning tank and from time to time flushes them away to drain. Ion exchangers are often used for water softening. When an ion exchanger is applied for water softening, it will replace the calcium and magnesium ions in the water with other ions, for instance sodium or potassium. The exchanger ions are added to the ion exchanger reservoir as sodium and potassium salts (NaCl and KCl).

How long does a water softener last?

A good water softener will last many years. Softeners that were supplied in the 1980’s may still work, and many need little maintenance, besides filling them with salt occasionally.

How much does a water softener cost?

Costs of a water softener greatly depend upon the type of water softener and the type of energy that is used, but also upon the hardness of the water that needs softening and the water use. When the water is very hard and it is used heavily, the costs of softening will rise. Generally the costs of installing a water softener may vary from Rs 17000 to Rs 25000 The costs of water softeners are usually far outweighed by the benefits and cost savings obtained, through using softened

Is softened water safe to drink?

Softened water still contains all the natural minerals that we need. It is only deprived off its calcium and magnesium contents, and some sodium is added during the softening process. That is why in most cases, softened water is perfectly safe to drink. It is advisable that softened water contains only up to 300mg/L of sodium. In areas with very high hardness the softened water must not be used for the preparation of baby-milk, due to the high sodium content after the softening process has been carried out.

Can salt from softening installations enter drinking water?

Salt does not have the opportunity to enter drinking water through softening installations. The only purpose of salt in a water softener is to regenerate the resin beads that take the hardness out of water.

When does a softener resin need replacement?

When the water does not become soft enough, one should first consider problems with the salt that is used, or mechanical malfunctions of softener components. When these elements are not the cause of the unsatisfactory water softening, it may be time to replace the softener resin, or perhaps even the entire softener. Through experience we know that most softener resins and ion exchange resins last about twenty to twenty-five years.

How often softener brine tanks need to be cleaned?

Usually it is not necessary to clean out a brine tank, unless the salt product being used is high in water-insoluble matter, or there is a serious malfunction of some sort. If there is a build-up of insoluble matter in the resin, the reservoir should be cleaned out to prevent softener malfunction

Can I shift the water softener from one place to the other?

It is very to take them along during moving. Installation techniques involve quick fitting connections, similar to those used for laundry machines. All that has to be done is closing off the inlet and outlet valves of the softener and open up the bypass valve, allowing hard water to flow to the storage tank and household taps. After that the softener can be disconnected, moved to its new location and placed there.

Can waste from a water softener be discharged directly in the garden?

Direct discharge of either sodium or potassium chloride brine should be avoided,  as brine alters the osmotic pressure that plants rely upon to regulate water needs.

How do I remove iron from my well water?

Iron content in your well water supply is not a health concern, but it can make the appearance and taste of your water quite unappealing. In addition, it can stain your dishes and silverware. There are several options available for treatment of your well water, depending on the type of iron present:

  • Water filtration/aeration
  • Add a water softener
  • Chlorination of water supply

Before you take any steps, you should first determine the type and level of iron in your well water. Contact a professional water testing company near you to perform the necessary tests.

What is the benefit of removing iron from water?

Our Iron Removal Filter System is perfect for removing the iron, unpleasant smell, taste and ugly staining from the water. Besides this, our Filters for Iron Removal also protect the plumbing and retard the concentration of the suspended solids. Precisely designed to solve all the problems pertaining to suspended particles present in the water, our Filters for Iron Removal are a cost effective solution. Our Iron Removal Water Filters make the water free from the iron contents and make it safe to use & drink. Easy to install, our Iron Removal Water Filters need low maintenance cost.

How do iron filters work?

Iron or steel will rust in the presence of air and water. Rust is one type of oxidation. When your water is underground in your well, it is clear, also known as ‘ferrous’ or clear water iron. Iron filters take this clear iron and transform it to rust or ferric iron in the process known as oxidation. These trapped particles are periodically and automatically backwashed out to drain, usually once or twice a week.

Which is the best iron filter for my application?

This depends on your source water quality. The first step is finding out if your cold water has a sulfur odor in it, or if it is just the hot water. If the water does have odor, then you need an iron filter that works in removing this sulfur odor, or you need to inject chlorine, ozone or hydrogen peroxide. The next step is to find out how much iron and manganese you have, and determine the pH (acidity or alkalinity) of your water. However you don’t have to become an expert water quality professional in order to find out the simple parameters you need to know before selecting an iron filter.

What does a wastewater treatment plant do?

Treatment plants remove impurities contained in wastewater so that the treated wastewater can be safely returned to the environment. This same stabilization process occurs in nature to break down wastewater into its most basic components of carbon dioxide and water. Common methods of treatment include physical, biological and chemical treatment steps to stabilize the wastewater.

What levels of treatment do your facilities provide?

The design and equipment selection for our system is based on the treatment levels required by the customer and local pollution control board regulations. Whatever treatment level you need, we can accomplish it.