Upgrade Your STP/ETP with Advanced Biocultures for Maximum Performance.
Sewage is mostly water—99.9% clean, with only 0.1% impurities. These impurities include organic waste, suspended solids, and microorganisms. Without proper treatment, sewage can contaminate water sources and harm the environment.
A sewage treatment plant (STP) removes these contaminants through a series of physical, biological, and chemical processes. The treated water, called effluent, can be safely released into the environment or reused for applications like irrigation and toilet flushing.
But how does an STP work? What technologies are used? Let’s break it down.
Stages of Sewage Treatment
Sewage treatment happens in three main stages:
Each stage plays a crucial role in making wastewater safe.
Primary Treatment: Removing Large Contaminants
This stage physically removes solids and floating materials from sewage. Key components include:
- Screen Chamber & Oil/Grease Trap – Filters out plastics, paper, and floating oils.
- Equalization Tank – Collects and aerates wastewater to balance flow and prevent shock loads.
Once the sewage is stabilized, it moves to secondary treatment.
Secondary Treatment: Breaking Down Organic Matter
This stage uses biological processes to remove organic and inorganic contaminants. Several technologies are available:
Activated Sludge Process (ASP)
Microorganisms break down organic matter in an aeration tank. Air is continuously supplied to keep bacteria active, converting pollutants into harmless substances.
MBBR (Moving Bed Biofilm Reactor)
MBBR uses floating bio-media to support bacteria growth. The bacteria consume organic matter, reducing contaminants. This system is efficient and requires less space.
SAFF (Submerged Aerobic Fixed Film Reactor)
SAFF combines fixed bio-media and aeration to break down organic pollutants. It is energy-efficient and produces minimal sludge.
SBR (Sequencing Batch Reactor)
SBR treats wastewater in batches, following a cycle of filling, aeration, settling, decanting, and sludge removal. It is ideal for fluctuating sewage loads.
MBR (Membrane Bioreactor)
MBR combines biological treatment with membrane filtration. It produces high-quality treated water suitable for reuse.
Each technology has its advantages. Which one suits your needs?
Tertiary Treatment: Final Purification
This stage removes any remaining impurities before discharge or reuse.
- Sand Filter – Removes fine suspended solids.
- Activated Carbon Filter – Eliminates odor and organic residues.
- Disinfection – Chemicals like sodium hypochlorite ensure the treated water is safe.
With proper tertiary treatment, wastewater can be used for gardening, flushing, and other non-potable applications.
Sludge Handling: Managing Waste Byproducts
Sludge, the solid waste from treatment, needs proper disposal. Methods include:
- Sand Filter – Removes fine suspended solids.
- Activated Carbon Filter – Eliminates odor and organic residues.
- Disinfection – Chemicals like sodium hypochlorite ensure the treated water is safe.
Efficient sludge management minimizes environmental impact.
Why Sewage Treatment Plants Matter
Without proper treatment, sewage pollutes water bodies, harms ecosystems, and spreads diseases. STPs protect public health and enable water reuse, reducing demand on freshwater sources.
Want to optimize wastewater treatment for your facility? Let’s talk.