Etp Bushes

Industrial wastewater (effluent) is treated in a number of ways; the level of treatment decides which is appropriate. Basically there are four steps: Preliminary, Primary, Secondary and Tertiary.
Preliminary Treatment: Screening, grit and oil removal are done at preliminary treatment process.
Primary Treatment: Primary treatment involves removal of suspended solids up to 50% and reducing BOD level up to 30%.
Secondary Treatment: This is sometimes referred to Biological Treatment. Through biological processes, dissolved and suspended organic wastes are converted to more stable solids and removed by settling.
Tertiary Treatment: It is the final stage which involves physical, chemical and biological processes to remove residual suspended solids and dissolved solids.