mbbr mbr sbr asp

Sewage Treatment Plants (STP) and Their Technologies A Sewage Treatment Plant (STP) is a treatment system designed to treat domestic wastewater generated from toilets, bathrooms, kitchens, residential townships, hotels, hospitals, commercial buildings and industries. The purpose is to remove suspended solids, organic pollutants, nutrients and pathogens so that treated water can be reused or discharged as per applicable pollution-control requirements. 1. Major STP technologies 1. ASP – Activated Sludge Process Conventional technology Uses biological treatment in an aeration tank followed by secondary clarification. Microorganisms consume dissolved and biodegradable organic matter. Main units: Screening, grit removal, equalization, aeration tank, secondary clarifier, sludge handling and disinfection. Suitable for: Residential townships, hotels, commercial buildings and large sewage flows. 2. MBBR – Moving Bed Biofilm Reactor Compact and robust Uses floating plastic carrier media on which microorganisms grow as a biofilm. Aeration and mixing keep the media moving. Main units: Screening, equalization, MBBR tank, media retention screens, secondary clarifier, filtration and disinfection. Suitable for: Apartments, hotels, hospitals, retrofit projects and space-constrained STPs. 3. MBR – Membrane Bioreactor High-quality treated water Combines biological treatment with membrane filtration. Membranes separate suspended solids and biomass from the treated water. Main units: Screening, equalization, biological reactor, membrane tank, permeate pumps, membrane cleaning system and disinfection where required. Suitable for: Premium residential projects, high-rise buildings, hotels and applications requiring high-quality reuse water. Key advantage: Small footprint and very low suspended solids in membrane permeate. 4. SBR – Sequencing Batch Reactor Treats sewage in batches inside a reactor, using timed cycles for filling, aeration, settling and decanting. Main units: Screening, equalization, SBR reactor, decanter, sludge handling and disinfection. Suitable for: Residential townships, institutions, hotels and developments with variable wastewater flows. Key advantage: Biological treatment and settling occur in the same reactor, reducing the need for a separate secondary clarifier. 5. Extended Aeration Process A variation of the activated sludge process that uses longer aeration time and generally lower organic loading. Suitable for: Small to medium residential complexes, schools, offices and institutions. Key advantage: Relatively simple operation and generally lower sludge production than conventional high-rate activated sludge systems, depending on operating conditions. 6. Anaerobic Treatment – UASB / ABR** Uses microorganisms that break down organic matter without oxygen. UASB means Upflow Anaerobic Sludge Blanket; ABR means Anaerobic Baffled Reactor. Suitable for: Certain large municipal sewage systems, warm-climate applications and projects where energy-efficient bulk organic removal is important. Important: Anaerobic treatment alone often does not achieve the final quality required for reuse or stringent discharge. Post-treatment is usually needed.