Introduction of Water treatment Chemicals

In order to discharge or reuse the wastewater after treatment, a variety of chemicals are required in the wastewater sewage water treatment process.

According to different uses, these agents can be divided into the following categories:

Flocculant

Coagulant Aid

Conditioner

Demulsifier

Defoamer

PH Regulator

Redox

Disinfectant

Types of Water Treatment Chemicals

1.Flocculant

Flocculant sometimes called coagulant, it can be used as a means to strengthen solid-liquid separation, and is used in primary sedimentation tank, secondary sedimentation tank, flotation tank, tertiary treatment or advanced treatment and other process links.

2.Coagulant Aid

Coagulant aid plays a role in strengthening the flocculation effect.

In the flocculation process of wastewater sewage water treatment, sometimes the use of a single flocculant cannot achieve good coagulation effect, and it is often necessary to add some auxiliary agents to improve the coagulation effect, which are called coagulant aids.

Some coagulant aids themselves do not play a role in coagulation, but play a role in assisting flocculants to produce coagulation effect by adjusting and improving coagulation conditions. Some coagulant aids are involved in the formation of flocs, improve the structure of flocs, and can change the small and loose flocs produced by inorganic flocculants into large and dense alum flowers.

3.Conditioner

Conditioner is also known as dehydrating agent, it is used to regulate the residual sludge before dehydration, and its varieties include some of the above flocculants and coagulant aids.

4.Demulsifier

Demulsifier is sometimes called destabilizing agent, it is mainly used for pretreatment of oily wastewater containing emulsified oil before flotation. Its varieties include some of the above flocculants and coagulant aids.

In the air flotation process, sometimes in order to improve the dispersion and flotation effect of reagents (such as collectors), emulsifiers need to be added first to emulsify the reagents; Some beneficiation reagents are easy to be emulsified, while the emulsified foam in the pulp will affect the subsequent process, resulting in concentrate overflow loss or river pollution caused by tailings wastewater. For this reason, demulsifier shall be added for treatment under the above conditions.

5.Defoamer

Defoamer is mainly used to eliminate a large amount of foam in the process of aeration or mixing.

6.PH regulator

PH regulator is used to adjust the pH value of acidic wastewater and alkaline wastewater to neutral.

When the pH value of acidic wastewater is raised, alkali or alkaline oxide is used as neutralizer, while when the pH value of alkaline wastewater is lowered, acid or acidic oxide is used as neutralizer.

The neutralizers commonly used for adjusting the pH value of acidic wastewater include lime, limestone, dolomite, sodium hydroxide, sodium carbonate, etc., while sulfuric acid and hydrochloric acid are generally used for adjusting the pH value of alkaline wastewater.

7.Redox

Redox is used for the treatment of industrial wastewater containing oxidizing or reducing substances.

Both substances with different redox potentials can relatively become oxidants or reducers, but the oxidants or reducers that can be used in wastewater treatment practice must meet the following requirements:

① It has a good oxidation or reduction effect on pollutants that are expected to be removed from wastewater,

② The substances generated after reaction shall be harmless to avoid secondary pollution,

③ The price is cheap and the source is reliable,

④ It can react quickly at room temperature without heating,

⑤ The pH value required for the reaction should be neutral, not too high or too low.

8.Disinfectant

Disinfectant is used for disinfection after wastewater sewage water treatment and before discharge or reuse.

#QDEVU #WATERTREATMENT #WASTEWATERTREATMENT #SEWAGEWATERTREATMENT