What are the chemical used for coagulation?
Traditional chemical coagulation uses aluminum and iron coagulants. The most common aluminum coagulants are aluminum sulfate, aluminum chloride, and sodium aluminate. Iron coagulants include ferric sulfate, ferrous sulfate, ferric chloride, and ferric chloride sulfate [4].
What is a coagulation reaction?
Coagulation is the process by which particles become destabilized and begin to clump together. Coagulation is an essential component in water treatment operations. Evaluation and optimization of the coagulation/rapid mixing step of the water treatment process includes a variety of aspects.
What does a chemical coagulant cause?
The sedimentation process can be quickened by adding special chemicals, also known as coagulants, to the water. Coagulants help the sand, silt, and clay join together and form larger clumps, making it easier for them to settle to the bottom of the container.
Which agent is used as coagulating agent?
Aluminum (Al) salts are widely used as coagulant agents due to the peculiar ability to remove small particles and humic acid moieties from natural waters.
What is coagulation give the examples of coagulating agents with relevant chemical reactions?
The aluminum coagulants include aluminum sulfate, aluminum chloride and sodium aluminate. The iron coagulants include ferric sulfate, ferrous sulfate, ferric chloride and ferric chloride sulfate. Other chemicals used as coagulants include hydrated lime and magnesium carbonate.
What happens in coagulation water treatment?
Coagulation is the chemical water treatment process used to remove solids from water, by manipulating electrostatic charges of particles suspended in water. This process introduces small, highly charged molecules into water to destabilize the charges on particles, colloids, or oily materials in suspension.
Does all coagulants react at all pH?
The optimum pH range varies depending on the coagulants used, but is usually between 5 and 7. These lower pH values mean that there are more positively charged particles loose in the water to react with the negatively charged colloids.
What happens during the coagulation process?
Tiny cells in the blood called platelets stick together around the wound to patch the leak. Blood proteins and platelets come together and form what is known as a fibrin clot. The clot acts like a mesh to stop the bleeding. Bleeding causes a biological “domino effect” in which a series of steps are set in motion.
Is FeCl3 a coagulant?
Aluminium and ferric based coagulants is widely used in drinking water treatment [3, 6]. The most commonly used aluminium-based coagulant has been ferric chloride (FeCl3), with other coagulants including aluminium chloride (AlCl3). Trivalent ferric ions are released into a solution from the respective salt.
What role does coagulation play in water treatment?
What is the most commonly used coagulant *?
Aluminum sulfate (alum)
Aluminum sulfate (alum) is the most common coagulant used for water purification. Other chemicals, such as ferric sulfate or sodium aluminate, may also be used. Coagulation is usually accomplished in two stages: rapid mixing and slow mixing.
What are the different coagulating agents?
A coagulating agent, such as a water-soluble organic compound or inorganic salt or acid, can be added to the dispersion. Examples of the organic compound include methanol and acetone. Inorganic salts, such as potassium nitrate and ammonium carbonate, and inorganic acids, such as nitric acid and hydrochloric acid, can aid coagulation.
What is chemical coagulation?
Chemical coagulation is an essential part of drinking water and wastewater treatment. In drinking water, it is used for the clarification of water, using coagulant agents mainly for municipal water treatment.
What are the side effects of coagulants in chemical reactions?
Yet, a chemical coagulant is added with an anion, such as sulfate or chloride, which may have some influence on the efficiency of the process. In some cases side reactions, such as reduction on the cathode surface, may play an important role in the destabilization of pollutants.
What is coagulation of the filaments?
Coagulation of the filaments involves two-way mass transfer with the coagulating agent (e.g. acid) diffusing inwards into the filaments and the chemical products of coagulation (e.g. salts, H2 S) diffusing outwards. It is sometimes necessary to use an intermediate process to produce a solution.