BIOLOGICAL
PROCESS
1. ACTIVATED SLUDGE PROCESS ( CONVENTIONAL METHOD)
Wastewater is aerated in a tank Bacteria are encouraged to grow by providing​
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Oxygen
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Food (BOD)
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Nutrients
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Correct temperature
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Time
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As bacteria consume BOD, they grow and multiply
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Treated wastewater flows into secondary clarifier
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Bacterial cells settle, removed from clarifier as sludge
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Part of sludge is recycled back to activated sludge tank, to maintain bacteria population
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Remainder of sludge is wasted
2. SEQUENCING BATCH REACTOR (SBR)
Sequencing batch reactors (SBR) or sequential batch reactors are a type of activated sludge process for the treatment of wastewater. SBR reactors treat wastewater such as sewage or mechanical biological treatment facilities in batches. Oxygen is bubbled through the mixture of wastewater and activated sludge to reduce the organic matter (measured as biochemical oxygen demand (BOD) and chemical oxygen demand (COD)). The treated effluent may be suitable for discharge to surface waters or possibly for use on land.
3. MOVING BED BIO FILM REACTOR (MBBR)
MBBR technology employs thousands of polyethylene bio-film carriers operating in mixed motion within an aerated wastewater treatment basin. Each individual bio-carrier increases productivity through providing protected surface area to support the growth of heterotrophic and autotrophic bacteria within its cells. It is this high-density population of bacteria that achieves high-rate biodegradation within the system, while also offering process reliability and ease of operation. This technology provides cost-effective treatment with minimal maintenance since MBBR processes selfmaintain an optimum level of productive bio-film. Additionally, the bio-film attached to the mobile bio-carriers within the system automatically responds to load fluctuations.
4. MEMBRANE BIO REACTOR (MBR)
MBR processes can produce effluent of high quality enough to be discharged to coastal, surface or brackish waterways or to be reclaimed for urban irrigation. Other advantages of MBRs over conventional processes include small footprint, easy retrofit and upgrade of old wastewater treatment plants. It is possible to operate MBR processes at higher mixed liquor suspended solids (MLSS) concentrations compared to conventional settlement separation systems, thus reducing the reactor volume to achieve the same loading rate. Membrane bioreactors can be used to reduce the footprint of an activated sludge sewage treatment system by removing some of the liquid component of the mixed liquor. This leaves a concentrated waste product that is then treated using the activated sludge process
5. PLASMA ELECTRO-OXIDATION TECHNOLOGY
6. ADVANCED OXIDATION PROCESS (AOP)