Types of Sewage Treatment

Sewage treatment is essential for protecting public health, conserving water, and preventing pollution. As water scarcity becomes a pressing issue in India, understanding the types of sewage treatment and their applications is critical for sustainable living.

Sewage treatment happens at three levels – primary, secondary, and tertiary. Each level uses different processes and technologies, determining how treated wastewater can be reused.

What is Sewage Treatment and What are its Types?

Sewage treatment is the process of removing contaminants from wastewater to produce water that is safe for disposal or reuse. The treatment level selected depends on the type of wastewater and the intended use of the treated water.

Primary Sewage Treatment:

Human Waste Treatment with our Bio-digester

Primary treatment is the simplest form of sewage management and focuses only on black water – wastewater from toilets.

• Process and Technology: Black water enters a biodigester, where naturally occurring bacteria break down organic matter. The resulting effluent is clear, odourless, and debris-free.

• Reuse Potential: No reuse. The treated water is suitable only for discharge into a soak pit or municipal drainage system.

• Best Suited For: Rural households, individual toilets, and areas without centralised sewer systems.

This level ensures safe disposal but does not support water recycling.

Secondary Sewage Treatment:

Wastewater Treatment with our PSTPs

Secondary treatment handles both black water (toilet waste) and grey water (from bathrooms, kitchens, and washing machines).

• Process and Technology: Wastewater is processed in a Packaged Sewage Treatment Plant (PSTP). Biological treatment and filtration remove organic contaminants and suspended solids.

• Reuse Potential: Treated water is clean enough for landscape irrigation and gardening. It is not suitable for indoor applications like flushing.

• Best Suited For: Residential communities, schools, and small institutions looking to reuse water for green spaces.

This level helps reduce freshwater usage for outdoor needs.

Tertiary Sewage Treatment:

Advanced Wastewater Treatment with our STPs

Tertiary treatment provides the highest level of wastewater treatment, ensuring that treated water meets stringent quality standards.

• Process and Technology: Advanced systems such as filtration, disinfection (UV or chlorination), and sometimes Reverse Osmosis (RO) are used to polish water after secondary treatment.

• Reuse Potential: Treated water is suitable for all non-potable uses, including toilet flushing, gardening, floor cleaning, and HVAC systems.

• Best Suited For: Malls, hotels, large residential complexes, and commercial buildings with high water demand.

This level enables sustainable water management by recycling wastewater for multiple applications and reducing freshwater dependence. There are various technologies for this. Read more about them here.

Why Choose the Right Sewage Treatment Level?

In India, untreated sewage often pollutes rivers and groundwater, creating serious health and environmental risks. Selecting the appropriate treatment level can:

• Ensure compliance with environmental regulations

• Conserve water and reduce freshwater demand

• Support sustainability initiatives in urban and rural areas

At Banka Bio, we provide end-to-end sewage treatment and reuse solutions. From biodigesters for rural homes to tertiary sewage treatment plants for urban reuse, we help our clients meet their water sustainability goals.

Build a Sustainable Water Future

Are you planning a sewage treatment system for your home, community, or business?Contact Banka Bio today to explore the right solution for your needs.