MBBR based compact sewage treatment plant.
Description:To have eco-friendly & natural treatment, this plant is designed based on the biological treatment concept. This means naturally occurring microbes (which are present in sewage water itself) removes or degrade the organic matter present in the sewage & at the end clean water is available for the non potable usage or to dispose safely in the drainage or river bodies as per the norms.
Methods:- Pre – Treatment Screening : This is the first units of the plant in which large or floating materials in the sewage gets arrested and blockage or choking of the downstream equipments can be avoided. This arrested material will be removed manually and then will be disposed off suitably Equalization : To absorb variation in quantity and quality of sewage and to provide uniform flow at the downstream treatment process, a collection or equalization tank is provided. This will avoid shock loading and process upsets of the treatment plant. To avoid settling of suspended solids in this tank continues air agitation is provided. If at site, septic tank is provided then collection tank as well as air agitation is not required.
- Biological Treatment : This is the main section of the plant where degradation of organic pollutants with the help of aerobic micro-organism takes place. To provide higher surface area for micro-organism, floating media is provided. On which micro-organism growth takes place. This makes bioreactor is of hybrid concept in which both suspended growth as well as attached growth principal for micro-organism is achieved. Due to higher population of micro-organism, effective volume of bioreactor reduced drastically as compared to conventional aeration tanks. To maintain the aerobic condition in the bioreactor, air supply arrangement is provided by means of aeration equipment which has high oxygen transfer efficiency Tube Settler : Gravity overflow from the bioreactor is collected in the tube settler tank. In this settling tank, generated sludge from the bioreactor undergoes a gravity settling. Clear supernatant from settling tank will flow by gravity to a chlorine contact tank. To reduce the plan area of settling tank, tube modules are placed in this tank to increase the settling area of the tank. Since this tank is a hopper bottom tank due to which there is no need of sludge scrapping mechanisms.
- Disinfection : Supernatant from Tube settler, flow by gravity to the chlorine contact tank. To disinfect the harmful bacteria in the treated water as well as to remove the refractory organics from treated water, in this tank hypo chlorite solution is dosed with the help of dosing system. Sludge Handling System : Generated sludge from clarifier/tube settler is pumped to either sludge holding tank or any sludge dewatering equipment
- Tertiary treatment : Secondary treated water will be further passed through pressure sand filter followed by activated carbon filter. Filtered water will be collected in the Treated water Storage tank from where it will be for desired non potable application. Backwashed water from filters will return back to equalization tank.
