Let's get to know the chemical wastewater treatment processes that we can commonly find

Chemical wastewater treatment systems can treat a variety of wastewater, but it is necessary to select one that is appropriate for the wastewater conditions that need to be treated. Generally, there are 3 methods.

1. Coagulation: Chemicals are added to the water to react with impurities such as suspensions containing negative ions such as clay, dyes from dye factories, and heavy metals. The chemicals used should be carbides such as alum and iron salts. When using this method, it is recommended to use iron salt because it is cheap and requires less quantity than alum. It also gives good results and is equally effective.

2. Neutralization: When releasing treated wastewater into the environment, the pH must be between 5.5 to 9.0 (according to the wastewater standards of the Industrial Estate Authority of Thailand).

✅ If the wastewater is too acidic, Sodium Hydroxide (NaOH) or Ammonia (NH3) can be added to

neutralize the water.

✅ If the wastewater is too alkaline, Sulfuric Acid (H2SO4), Hydrochloric Acid (HCL) or carbon

dioxide gas (CO2) can be added.

3. Disinfection: Bacteria and fungi are one of the reasons why untreated wastewater cannot be released into the environment. Disinfection of wastewater requires the use of chemical wastewater treatment systems such as the addition of chlorine, chlorine compounds or phenolic compounds to the wastewater.