What chemicals are commonly used for water treatment?
- Oxygen scavengers. The process of oxygen scavenging prevents oxygen from producing oxidation reactions. A typical...
- Flocculants. Flocculants help flocs formulate in water. Flocs are cloudy suspensions of cells, formed from bacterial...
- Neutralising agents. Neutralising agents in water treatment neutralise acids and...
Which chemicals are used to purify the water?
The chemicals used in water treatment are: Jacid. chlorine. chlorine dioxide. hydrochloric acid. soda ash or sodium bicarbonate. In addition to the chemicals mentioned above, there are many other chemicals used in water treatment. Coagulants, flocculants, softeners, and filter cleaners also form an important part of water treatment methods.
What chemicals are used to disinfect water?
In chemical softening, various chemical combinations are added to raw water to remove hardness, silica, and silt from the makeup water. Economics and boiler operating conditions dictate the technique selected for the application. Additives can contain, e.g., lime, phosphate, or …
What chemicals are used to clean water wells?
· Obviously either an acid or a base chemical will be used, depending on the pH level of the water. The most used acid is Sulfuric Acid. This is due to its cost, abundance, and …
What are two chemicals used to purify water?
Chemical Wastewater Treatment Processes. Neutralization. Neutralization involves the addition of chemicals for the purpose of adjusting the pH of the wastewater. This involves the addition …
Why are the chemicals used for water treatment important?
Nowadays, the demand for potable water is constantly increasing, due to meeting human needs and supporting industrial activities. With increasing urbanization and economic development, the current water supply is unlikely to meet the ever-increasing demands.
The chemicals used in water treatment are
In addition to the chemicals mentioned above, there are many other chemicals used in water treatment. Coagulants, flocculants, softeners, and filter cleaners also form an important part of water treatment methods.
Aluminum sulfate
Aluminum sulfate is the main substance that helps condense pollutants in water. And adding slaked lime to adjust the pH of the water to get the best effect after thickening. Polyelectrolytes are used for condensation. It uses chlorine in addition to activated carbon.
The importance of water treatment
The water treatment industry plays an important role in providing clean water and preventing various water-related diseases across the world. With the help of innovative boiler water treatment chemicals and other related chemicals. It is now possible to make polluted seawater, river waste, and sewage safe for human consumption.
Coagulation and flocculation
The two are usually the first steps in water treatment in which positively charged chemicals are added to the water. The positive charge of these chemicals neutralizes the negative charge of dirt and other dissolved particles in the water. When this happens, the particles combine with the chemicals and form larger particles called agglomerates.
Sedimentation
The conglomerates settle due to their weight at the bottom of the water source during sedimentation. This process is called sedimentation, where the sedimentation or sediment resulting from the coagulation and flocculation process takes place in the subsequent stages.
Purification
After removing the sludge, we enter the filtration stage. During this process, the sludge passes through the material layer, which helps to remove organic matter and particles that were not removed before by coagulation. The material used is usually a layer of sand over a layer of gravel.
What is boiler water treatment?
Boiler water treatment has basically two phases: First, we remove impurities from the water to the desired cleanliness. Second, we add chemicals to the feedwater to adjust the pH, create less favorable conditions for deposition, and remove oxygen. Special water treatment chemicals are used in almost all boilers.
What is demineralization of water?
Synthetic cation and anion exchange resins are used in the demineralization of water. The cation exchanger is regenerated with acid, while the anion exchange material is regenerated with caustic. Demineralization can yield a pure water, equal or superior to the best evaporated water. The anion and cation resins can be arranged in various combinations to produce the best water most economically. Two-, three-, or four-bed units, or a single mixed-bed demineralizer can be used to accomplish the required result (Fig. 8.8 ).
What is NOM in water?
Natural organic matter (NOM) is a complex matrix of organic materials and a key component in aquatic environments. As a result of the interactions between the hydrologic cycle and the biosphere and geosphere, the water sources of drinking water generally contain NOM. The amount, character, and properties of NOM vary considerably according to the origins of the waters and depend on the biogeochemical cycles of their surrounding environments. Also, the interrelation between NOM and climate change has attracted a great deal of attention in recent research. NOM has a significant impact on many aspects of water treatment, including the performance of unit processes, necessity for and application of water treatment chemicals, and the biological stability of the water. As a result, NOM affects potable water quality as a carrier of metals and hydrophobic organic chemicals and by contributing to undesirable color, taste, and odor problems. Moreover, NOM has been found to be the major contributor to disinfection by-product (DBP) formation. Changes in NOM quantity and quality have a significant influence on the selection, design, and operation of water treatment processes. These changes also cause operational difficulties in water utilities. High seasonal variability and the trend toward elevated levels of NOM concentration pose challenges to water treatment facilities in terms of operational optimization and proper process control. To improve and optimize these processes, it is vital to characterize and quantify NOM at various stages during the purification and treatment process. It is also essential to be able to understand and predict the reactivity of NOM or its fractions during different phases of the treatment. Once the composition and quantity of NOM in the water source has been examined, suitable methods for efficient NOM removal can be applied. No single process alone can be used to treat NOM due to its high variability. The most common and economically feasible process available is coagulation and flocculation followed by sedimentation/flotation and filtration. Other treatment options for NOM removal include magnetic ion exchange resin (MIEX®) techniques, activated carbon filtration, membrane filtration methods, and advanced oxidation processes.
What is the best way to combat fouling?
Combating fouling requires injection of antibiological agents, water-treatment chemicals, insulation systems, and deicing agents, depending on the cause. Apart from being expensive, chemicals can sometimes damage the coating and more often than not, are an inefficient means of control.
What is the purpose of cation exchange resin?
Synthetic cation and anion exchange resins are used in the demineralization of water. The cation exchanger is regenerated with acid, while the anion exchange material is regenerated with caustic. Demineralization can yield a pure water, equal or superior to the best evaporated water.
What is the purpose of coagulating materials?
Adding chemical coagulating materials reduces surface-water contamination in the form of coarse suspended solids, silt, turbidity, color, and colloids . The chemicals form a floc, which assists in agglomerating impurities. Settlement of the particles permits a clear effluent from the coagulating chamber.
How does water and air affect the solubility of carbon dioxide?
Carbon dioxide is also removed during aeration. The solubility of gas in water is directly proportional to its partial pressure in the surrounding atmosphere. The partial pressure of a gas such as carbon dioxide is low in a normal atmosphere.
Why does the chemical industry use water treatment?
Hence, the chemical industry uses the innovative ways of water treatment in order to make water acceptable for end-use, such as drinking, cooking, irrigation and industrial purpose to name a few.
What is water treatment?
Water treatment chemicals, a modern approach for safe drinking water. “Millions lived without love, none without water!”. This dihydrogen infused oxygen molecule forms the basis of all living forms on Earth. Whether it’s for cooking or basic sanitation needs, the role of water remains irreplaceable as the entire human survival depends on water.
Why is water treatment important?
The water treatment industry is playing an important role in providing clean water globally and prevents various water-related diseases. With the innovative boiler water treatment chemicals and other related chemicals, water from the sea, polluted rivers, and wastewater effluents can now be made safe for human consumption.
How many people die from drinking water every year?
It is estimated that about 3.4 million of the world’s population die every year due to deprived access to clean drinking water. Providing safe drinking water remains a global challenge, for which only chemistry has a solution.
What is the most common type of water treatment system?
The most common types of household water treatment systems consist of: Filtration Systems. A water filter is a device which removes impurities from water by means of a physical barrier, chemical, and/or biological process. Water Softeners. A water softener is a device that reduces the hardness of the water.
What happens when chemicals are added to water?
Chemicals with a positive charge are added to the water. The positive charge of these chemicals neutralizes the negative charge of dirt and other dissolved particles in the water. When this occurs, the particles bind with the chemicals and form larger particles, called floc. Sedimentation.
What is the process of boiled water?
Distillation is a process in which impure water is boiled and the steam is collected and condensed in a separate container, leaving many of the solid contaminants behind. Disinfection. Disinfection is a physical or chemical process in which pathogenic microorganisms are deactivated or killed.
What is a water softener?
Water Softeners. A water softener is a device that reduces the hardness of the water. A water softener typically uses sodium or potassium ions to replace calcium and magnesium ions, the ions that create “hardness.”. Distillation Systems.
Why do people use water treatment units?
Even though EPA regulates and sets standards for public drinking water, many Americans use a home water treatment unit to: Remove specific contaminants. Take extra precautions because a household member has a compromised immune system. Improve the taste of drinking water.
Why is surface water treated differently than ground water?
Typically, surface water requires more treatment and filtration than ground water because lakes, rivers, and streams contain more sediment and pollutants and are more likely to be contaminated than ground water.
What is the purpose of adding disinfectant to water?
After the water has been filtered, a disinfectant (for example, chlorine, chloramine) may be added in order to kill any remaining parasites, bacteria, and viruses, and to protect the water from germs when it is piped to homes and businesses.
What chemicals are used in wastewater?
Another use of chemicals in wastewater is for Disinfection . Commodity chemicals, like Bleach, produced in various concentrations, are often used for this purpose. One common concentration that OU offers, is our Sodium Hypochlorite 12.5%, but we offer other concentrations as well. Bleach is used for disinfection and production processes in all kinds of industrial applications including coatings, food processing, paper & packaging, pharmaceuticals, and more.
What chemicals are used to remove solids from water?
Several kinds of chemicals can aid in the process of removing solid particles from the water. Coagulant and Flocculant Polymers are important in this process. These polymers help the tiny particles in the water to begin to combine with each other to form larger particles and chains of particles that settle out of the water and drop to the bottom.
What is the purpose of anti foam?
To prevent foam from occurring , an Anti-foam chemical agent can be used. One other use of chemicals in wastewater treatment is for the purpose of Sludge Removal . The water must be removed from the sludge that is created in the wastewater treatment process. Often polymer chemicals are re-introduced into this stage of treatment to remove the water.
What is bleach used for?
Bleach is used for disinfection and production processes in all kinds of industrial applications including coatings, food processing, paper & packaging, pharmaceuticals, and more. Often foam can develop in the wastewater treatment process, which can cause many problems. In fact, the foam can stand in the way of measuring instruments getting ...
What are the effects of wastewater?
Unpleasant odors produced by the wastewater can impact employee morale, invite complaints from neighbors including other businesses, and even be a health hazard. It is a major issue that must be solved. For most industrial plants something more must be done than just “covering up” the problem to contain the odors.
What acid is used to adjust pH?
The most used acid is Sulfuric Acid. This is due to its cost, abundance, and effectiveness in adjusting the pH level. Other acids that are used include Hydrochloric Acid and Phosphoric Acid . As far as bases, some common chemicals that are effective are Sodium Hydroxide, Calcium Hydroxide (Lime), among others.
What is the most used acid in a plant?
Obviously either an acid or a base chemical will be used, depending on the pH level of the water. The most used acid is Sulfuric Acid.
What chemicals are used to disinfect wastewater?
Specialized chemicals such as chlorine, hydrogen peroxide, sodium chlorite, and sodium hypochlorite (bleach) act as agents that disinfect, sanitize, and assist in the purification of wastewater at treatment facilities. There are several distinct chemical unit processes, including chemical coagulation, chemical precipitation, chemical oxidation, ...
What is wastewater treatment?
The initial stage of wastewater treatment involves mechanical processes, which remove some 20-30% of solids in the water. First, the wastewater is directed to a screen or a sieve drum that filters out impurities that are relatively coarse, such as leaves, textiles, paper, or other large materials. A series of screens are used with various degrees ...
What is flocculant in wastewater?
Flocculation uses flocculants to help remove very fine particles from wastewater that would not normally accumulate as larger agglomerates as a result of their electrical repulsion from having an identical charge. By adding specialty chemicals, larger formulations of particles will occur which will then settle out in a sedimentation process.
What is the process of precipitation?
The chemical process of precipitation involves the addition of suitable agents to the wastewater which can transform dissolved substances to ones that are not easily soluble. With this transformation, the material precipitates and lowers the concentration of the material.
What are activated carbons used for?
In wastewater treatment, activated carbons are often used to bind to soluble elements in the water which were unable to be removed in earlier stages of the treatment process such as mechanical or biological. Colorants from textile dying, pharmaceutical residues, arsenic, and heavy metals are examples of substances that can be effectively removed through this process.
What is redox reaction?
Redox reactions are used for the treatment of potable water. Chlorinated hydrocarbons and pesticides can be effectively removed from wastewater by the use of ozone and hydrogen peroxide treatments. Advanced oxidation processes are also used for the degradation of drug substances like antibiotics or cytostatic drugs that might be found in the water. Reduction processes can also be used for the transformation of heavy metal ions into sulfides.
What happens to the oxidizing agent during chemical oxidation?
With the introduction of an oxidizing agent during chemical oxidation, electrons move from the oxidant to the pollutants in wastewater. The pollutants then undergo structural modification, becoming less destructive compounds. Alkaline chlorination uses chlorine as an oxidant against cyanide.
What do water companies need?
Water companies routinely require the services of vendors and suppliers that can provide various types of metering pumps, carry out required construction or installation, and also sell individual components that are needed by the wastewater treatment plant. Not sure where to begin? Speak with chemical dosing industry experts
What equipment does a water company need?
Furthermore, keeping these dosing requirements going is a big task for water companies that have fixed and predetermined suppliers for essential equipment such as pipework, electrical switchgear, and cables.
What is PH buffering?
PH buffering is a key function of the process of chemical dosing. Water treatment authorities have timings and patterns worked out so different dosing requirements exist for different times of the day. At midnight for example when not a lot of water is being used, PH levels maybe altered accordingly.
What is the process of PH buffering?
Buffering PH Levels. Lime or sodium hydroxide is dosed into a body of water according to very specific pH levels which are measured and noted. This process is called PH buffering and is essential for dosing relatively clean bodies of water such as the water found in tanks or tap water.
What is anaerobic process?
In sewage water treatment process for example, an anaerobic process is implemented which results in the creation of biofertilizer or biogas. Industrial wastewater or industrial effluent as it is commonly called also has environmental obligations regarding its treatment.
Why is phosphate removal important?
The removal of phosphate from the effluent of a sewage system is an essential part, because its one of the first steps in treating wastewater so that it can be utilized or returned to a natural water source.
What is chemical dosing?
Chemical dosing is quite simply the name given to the process of delivering a chosen chemical into a body of water. Dosing pumps inject a very specific amount of chemical into a liquid stream. Apart from wastewater treatment, there are various other applications for dosing pumps some of which can be used within oil and gas, food processing, ...
What is water treatment?
The water treatment process to deliver safe and wholesome water to customers includes many steps. Coagulation, flocculation, sedimentation, filtration, and disinfection are the water treatment processes that make up a conventional surface water treatment plant. These water treatment processes ensure that the water consumers receive is safe ...
Why do water systems need chemicals?
Water system operators must use chemicals in order to neutralize these small charges, help the particles attach to one another, and become heavy enough to settle out of solution.
How does water temperature affect coagulation?
Water temperature also impacts the coagulation process because it effects the viscosity of water. Both alum and ferric salts form flocs at a slower rate as the water temperature decreases.
What pH should a water be for coagulation?
The water’s pH has a large impact on the coagulants effectiveness during the destabilization process. The optimal pH range for coagulation is 6 to 7 when using alum, and 5.5 to 6.5 when using iron. A large amount of coagulant may be required to lower the pH into the optimal range for high alkalinity waters. This results in high chemical costs and large amounts of sludge produced in the treatment process. It therefore may be cost effective to add acid in addition to the coagulant to bring the pH down and reduce the amount of coagulant required in this situation.
What are the effects of aluminum and ferric coagulants on water?
As the particles collide in the mixing area they begin to stick together a form larger and larger flocs. Temperature, pH, alkalinity, and the amount of turbidity in the water control the reactions of aluminum and ferric salts in the water.
What are the common coagulants used today?
Common coagulants used today include aluminum sulphate (alum), ferric sulphate, ferric chloride, and sodium aluminate. Synthetic organic polymers were introduced in the 1960s. Depending on your system’s water quality, it may be necessary to employ a combination of two or more coagulants.
What is coagulation in water treatment?
History of Coagulation in Drinking Water Treatment. Coagulation has been an important process in high-rate filtration plants in the United States since the 1880s. Aluminum and iron salts have been used in the coagulation process since the beginning. These salts are still the most commonly used coagulants today.
Oxygen Scavengers
Flocculants
- Flocculants help flocs formulate in water. Flocs are cloudy suspensions of cells, formed from bacterial cells and fungal species. These organisms can help to reduce organic matter and reduce biological oxygen demand in water. They are used as part of sewage treatment. Flocculants are polymers that are water-soluble.
Neutralising Agents
- Neutralising agents in water treatment neutralise acids and basics. Their dosage will depend on the pH of the water. Some neutralising agents increase pH levels, and some will cause them to decline. Neutralising agents include solutions of sodium hydroxide and calcium carbonate, and diluted sulphuric acid and hydrochloric acid.
Ph Conditioners
- pH conditioners help adjust pH water levels. This can help to reduce corrosion in pipes and prevent any lead dissolving into water supplies. You can reduce or increase pH levels using basics or acids. Examples include hydrogen chloride, which is a basic liquid for reducing pH levels; and natrium hydroxide, which is an acid liquid for increasing pH levels in water.
Scale Inhibitors
- In hard water areas, limescale will form on surfaces in contact with water, due to increased levels of calcium and magnesium minerals. Scale inhibitors are negatively-charged polymers that are surface-active. They attach to minerals in water, disrupting their structures for crystallisation. This helps prevent scale from forming.
Corrosion Inhibitors
- Corrosion can be extremely damaging to boilers, heat exchange systems and other metallic devices and components where contact with water is normal. Corrosion inhibitors react with metallic surfaces, providing a level of protection, usually by forming a film on it. There are various forms of corrosion inhibitors, including passive, cathodic, organic, precipitation-inducing, and vol…
Coagulants
- Coagulants can remove suspended solids in water. They are made up of positively-charged molecules, and may be organic, inorganic or a combination of both. Chemicals commonly used as coagulants in drinking water treatment include: 1. Aluminium sulphate 2. Polyaluminium chloride 3. Ferric sulphate.
Antifoams
- When certain types of gas are dispersed into water this causes foam, which are masses of bubbles. Foam can cause serious problems with industrial processes, and in the quality of finished products. If left uncontrolled, foam may reduce the operational capacity of equipment, lengthening processes and increasing production costs. Antifoams blend oils with small amoun…
Algaecides
- Algaecides will kill algae when you add them to water. They can be highly effective in killing all algae present in water, but they cannot remove any toxins that the algae have already released. Examples of algaecides include benzalkonium chloride, copper sulphate, iron salts and rosin amine salts.
What Are Water Treatment Chemicals?
Common Water Treatment Chemicals
- The most commonly used chemicals for water treatment process are: 1. Algicide 2. Chlorine 3. Chlorine dioxide 4. Muriatic acid 5. Soda ash or Sodium bicarbonate In additions to the above chemicals, there are numerous other water treatment chemicals used. Coagulants, flocculants, clarifiers and filter cleaners also form an important part of water tr...
Embracing The Future Water Treatment Industry
- The water treatment industry is playing an important role in providing clean water globally and prevents various water-related diseases. With the innovative boiler water treatment chemicals and other related chemicals, water from the sea, polluted rivers, and wastewater effluents can now be made safe for human consumption. CeraMac at Andijk II, Netherlands have designed and develo…
Community Water Treatment
Water Fluoridation
- Community water fluoridation prevents tooth decay safely and effectively. Water fluoridation has been named one of 10 great public health achievements of the 20th century 1. For more information on the fluoridation process and to find details on your water system’s fluoridation, visit CDC’s Community Water Fluoridationpage. Top of Page
Consumer Confidence Reports
- Every community water supplier must provide an annual report, sometimes called a Consumer Confidence Report, or “CCR,” to its customers. The report provides information on your local drinking water quality, including the water’s source, contaminants found in the water, and how consumers can get involved in protecting drinking water. 1. View the CDC’s guide to Understandi…
Household Water Treatment
- Even though EPA regulates and sets standards for public drinking water, many Americans use a home water treatment unit to: 1. Remove specific contaminants 2. Take extra precautions because a household member has a compromised immune system 3. Improve the taste of drinking water Household water treatment systems are composed of two categories: point-of-us…