on the presence of oxygen. The advantages associated with this process are:
eco-friendly, cost-effectiveness, less sludge production, production of
non-hazardous metabolites, less requirement of water as compared to chemicalphysical process, etc. Here common microorganisms like bacteria, fungi and algae
are used for wastewater treatment. This treatment process is somewhat similar to that
followed in petroleum refineries. Bacteria, fungi, algae digest the dyes or organic
matter in presence of intra- or extracellular enzymes such lignin peroxidase, manganese peroxidase and laccase. Usually, the rot white fungi are cultured for removing azo dyes (Navin et al. 2018).
8.4.8 Wastewater Treatment in Paint Industry
Paint industry uses various raw materials like resins, solvents, extenders, pigments,
oil and grease. Wastewater from paint industry is also detrimental to human beings
and may disturb aquatic life. The wastewater treatment system in paint industry
consists of primary, secondary followed by biological treatment. By this treatment
process, 90–95% pollutants are removed (Silva and Barbosa 2016; Porwal 2015).
Primary Treatment
A. Oil and grease removal: At first, effluents from all processes except stiff paint
unit and caustic cleaning unit pass through an oil and grease disposal device.
B. Equalisation and neutralization: The effluents from stiff paint and caustic washing section are sent to the equalization or neutralization pond. In this pond, the
effluents mix with coagulants and next go to the flash mixer.
C. Clariflocculation: After equalization, the effluents are clarified in the
clariflocculator tank followed by biological treatment.
Secondary Treatment
A. Secondary clariflocculation: In first clariflocculator, the sludge generated is
passed through the secondary clariflocculator for biological treatment followed
by sludge drying bed for dewatering. Here, the biological treatment is same as
the biological treatment of textile and refinery wastewater.
8.4.9 Wastewater Treatment in Polymeric Industry
The effluents from polymeric industries consist of suspended solids, organic materials and residual polymers. These effluents look like a milky waste liquid with some
solid particles dispersed into the wastewater: colloids. This type of effluent is not
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eco-friendly, cost-effectiveness, less sludge production, production of
non-hazardous metabolites, less requirement of water as compared to chemicalphysical process, etc. Here common microorganisms like bacteria, fungi and algae
are used for wastewater treatment. This treatment process is somewhat similar to that
followed in petroleum refineries. Bacteria, fungi, algae digest the dyes or organic
matter in presence of intra- or extracellular enzymes such lignin peroxidase, manganese peroxidase and laccase. Usually, the rot white fungi are cultured for removing azo dyes (Navin et al. 2018).
8.4.8 Wastewater Treatment in Paint Industry
Paint industry uses various raw materials like resins, solvents, extenders, pigments,
oil and grease. Wastewater from paint industry is also detrimental to human beings
and may disturb aquatic life. The wastewater treatment system in paint industry
consists of primary, secondary followed by biological treatment. By this treatment
process, 90–95% pollutants are removed (Silva and Barbosa 2016; Porwal 2015).
Primary Treatment
A. Oil and grease removal: At first, effluents from all processes except stiff paint
unit and caustic cleaning unit pass through an oil and grease disposal device.
B. Equalisation and neutralization: The effluents from stiff paint and caustic washing section are sent to the equalization or neutralization pond. In this pond, the
effluents mix with coagulants and next go to the flash mixer.
C. Clariflocculation: After equalization, the effluents are clarified in the
clariflocculator tank followed by biological treatment.
Secondary Treatment
A. Secondary clariflocculation: In first clariflocculator, the sludge generated is
passed through the secondary clariflocculator for biological treatment followed
by sludge drying bed for dewatering. Here, the biological treatment is same as
the biological treatment of textile and refinery wastewater.
8.4.9 Wastewater Treatment in Polymeric Industry
The effluents from polymeric industries consist of suspended solids, organic materials and residual polymers. These effluents look like a milky waste liquid with some
solid particles dispersed into the wastewater: colloids. This type of effluent is not
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M. Samanta and D. Mitra