Activated Sludge Wastewater Treatment Systems | Jinwantong

Activated sludge wastewater treatment is a biological wastewater treatment process that uses microorganisms to remove dissolved and suspended organic pollutants from sewage or industrial effluent. It is one of the most common methods used in municipal wastewater treatment plants and many industrial wastewater projects because it can effectively reduce COD, BOD and, with suitable process control, ammonia nitrogen.
The basic idea is simple: wastewater enters an aeration tank where air or oxygen is supplied. Microorganisms grow in the mixed liquor and consume organic matter as food. These microorganisms form biological flocs, commonly called activated sludge. After aeration, the mixture flows into a secondary clarifier, where sludge settles and treated water is separated. Part of the settled sludge is returned to the aeration tank as return activated sludge, while excess sludge is removed for further treatment.
A complete activated sludge system usually includes pretreatment. Mechanical grilles or screens remove large solids, fibers, plastics and floating debris before the wastewater reaches pumps and biological tanks. Equalization may also be used when flow or pollutant concentration changes significantly. This is especially important for industrial wastewater, hotels, communities and food processing wastewater where discharge can fluctuate during the day.
The core treatment section includes the aeration tank, blower system, mixed liquor control, secondary clarification and sludge return. Proper aeration is essential because microorganisms need oxygen to degrade pollutants. If oxygen is too low, treatment efficiency may drop and odor may appear. If aeration is excessive, energy consumption increases. Sludge concentration, sludge age, dissolved oxygen, pH and nutrient balance all influence performance.
Activated sludge systems can also be combined with advanced or compact technologies. MBR sewage treatment systems use membranes instead of conventional secondary clarification, offering better solid-liquid separation and compact layout. MBBR wastewater treatment systems use biofilm carriers to improve biomass retention and load resistance. These options are often considered for packaged plants, limited-space projects or higher effluent requirements.
Clarification and sludge treatment are important for long-term operation. A lamella clarifier can improve solid-liquid separation in a smaller footprint. Excess sludge from biological treatment can be processed by screw press sludge dewatering equipment or other sludge treatment machines to reduce disposal volume and cost. Automatic dosing systems may be added for phosphorus removal, pH adjustment, coagulation or sludge conditioning.
For B2B buyers, process selection should be based on daily flow, peak flow, COD, BOD, TSS, ammonia nitrogen, phosphorus, pH, temperature, discharge limits, land area, sludge disposal plan and operator skill level. Qingdao Jinwantong can provide single equipment or integrated configurations for activated sludge wastewater treatment, MBR/MBBR systems and supporting treatment units. Buyers can send water quality data and project requirements to receive a customized proposal and quotation.