Water scarcity and strict wastewater discharge norms have made Sewage Treatment Plants (STP Plants) a necessity for modern infrastructure projects. Residential societies, commercial complexes, hospitals, hotels, and industries must treat sewage before discharge as per guidelines from the Central Pollution Control Board.
Koshish India is a trusted provider of advanced and cost-effective STP plant solutions in India, delivering customized systems that ensure environmental compliance and long-term operational efficiency. If you are searching for “STP plant manufacturer in India,” “STP plant cost per KLD,” “commercial STP plant installation,” “industrial sewage treatment plant supplier,” or “compact STP plant for apartments,” this detailed guide covers everything you need to know.
What is an STP Plant?
A Sewage Treatment Plant is a wastewater treatment system that removes contaminants such as:
Organic matter
Suspended solids
Oil and grease
Harmful bacteria and pathogens
Odor and color
After proper treatment, the water can be reused for:
Toilet flushing
Gardening and landscaping
Cooling towers
Construction activities
Industrial reuse
The main objective is to reduce BOD, COD, TSS, and microbial contaminants to meet discharge standards.
STP Plant Working Principle
The working process of an STP plant includes three key stages:
1. Primary Treatment
Bar screens remove large solid waste
Grit chambers eliminate sand and heavy particles
Primary clarifier settles sludge
This stage removes physical impurities from sewage.
2. Secondary (Biological) Treatment
Aeration tanks supply oxygen
Microorganisms break down organic pollutants
Secondary clarifier separates treated water from sludge
This stage significantly reduces organic load and improves water quality.
3. Tertiary Treatment
Pressure sand filters remove fine particles
Activated carbon filters eliminate odor and color
UV or chlorination ensures proper disinfection
The final treated water is safe