Sewage treatment is the process of removing contaminants from domestic waste water or sewage, both run off (effluents) and domestic. It includes physical, chemical, and biological processes to remove physical, chemical and biological contaminants. Its objective is to produce an environmentally-safe fluid waste stream (or treated effluent) and a solid waste.
Sewage is generated by residential, institutional, and commercial and industrial establishments. It includes household waste liquid from toilets, baths, showers, kitchens, sinks and so forth that is disposed of via sewers. In many areas, sewage also includes liquid waste from industry and commerce. The separation and draining of household waste into greywater and blackwater is becoming more common in the developed world, with greywater being permitted to be used for watering plants or recycled for flushing toilets.
Sewage may include stormwater runoff, Sewerage systems capable of handling stormwater are known as combined systems. Combined sewer systems are usually avoided now because precipitation causes widely varying flows reducing sewage treatment plant efficiency. Combined sewers require much larger and more expensive treatment facilities than sanitary sewers. Heavy storm runoff may overwhelm the sewage treatment system, causing a spill or overflow. Sanitary sewers are typically much smaller than combined sewers, and they are not designed to transport stormwater. Backups of raw sewage can occur if excessive Infiltration/Inflow is allowed into a sanitary sewer system.
Advantages of MBR
- The membrane filtration without settling tank allows the effluent water to flow into public stream directly, which results in saving the required space for it. Besides, MBR enables to reduce the aeration tank volume and the excess sludge generation volume in terms of raising biomass concentration in the aeration tank.
- It is unnecessary to manage the sophisticated sludge separation in operation at a settling tank. MBR makes the operation and maintenance easy in the biological treatment, which requires just only the observation of pressure loss for filtrate permeation.
- Effluent water quality is very fine and stable because membrane separation is not associated with sludge carry-over.
STP BIOFLA can produce high quality effluent with high BOD5 removal (about 98%), complete nitrification and partial denitrification. It also achieves virtually complete TSS removal. Treated effluents have low turbidity values (<0.7 NTU) and SDI values (<5) which can be re-used for landscaping, flushing or feed RO for higher purity water.
The benefits of STP BIOFLA include:
- space requirement much smaller ;
- production of less sludge due to high sludge age;
- increased volumetric loading;
- better solids removal(elimination of bulking);
- high SRT which allows the development of slow-growing microorganisms such as nitrifying bacteria; and
- retention of high molecular weight organic compounds that can enhance the biodegradation process.
STP BIOFLA can be delivered as a containerized unit. This solution has some advantages such as:
- easy to relocate
- short delivery period
- no construction works on-site
- factory installed and tested