Our ETP is based on Activated Sludge process, adopted internationally all over world in Pulp & Paper Industry. It consists of Equalisation tank, Saveall, Primary Clarifier, Aeration and Secondary Clarifier. In Aeration tank Biological process takes place where Bacteria (micro organism) eat up organic matter present in effluent thereby reducing BOD/COD. For growth of Micro organism) we need O2, N, P, pH neutral, minerals & micro nutrients.
Normally O2 is comes from Air through Diffuser and Surface Aerator in Aeration tank. But in our case alongwith Diffuser we are injecting pure Oxygen through turboxal Equipment procured from M/s. Air Liquid, France that helps in producing robust, efficient, healthy, Bigger molecular size Bacteria resulting in good settling tendency. It smoothens the reduction of BOD/COD and any shocks in the pollution load are also taken care of:
After substantial reduction in Hydraulic load and pollution load, effluent from all corners of the Plant is taken to Equalisation tank.
For Complete homogenisation of the effluent and prevention of sedimentation in the tank diffused aeration system is provided. The function of Equalisation tank is to avoid fluctuation in pollution load before ETP.
Total effluent from Equalisation tank taken to Saveall - Settled Sludge is taken on Decker for sludge removal, Clarified effluent is taken to Primary Clarifier.
Primary Clarifier facilitates the solid liquid separation and settling of suspended solids/fibres/debris as Primary sludge is removed through Belt Press while the Clarified effluent overflows to Aeration tank.
Organic matter present in the effluent is degraded by microbial Biomass (MLSS) in presence of Oxygen in Aeration tank. In Aeration tank we provide diffusers alongwith Blowers for Air supply.
To further improve the process we have installed an automated Oxygen injection System providing pure Oxygen through Turboxal complete total area of aerationBasin. The System is patented by Air Liquid France and is highly efficient for maintaining high quality MLSS for reduction of BOD/COD.
After oxidation/degradation of organic matter in the Aeration tank the effluent overflows into the Secondary Clarifier.
Secondary Clarifier facilitates the settling of excess Biomass which is recirculated into the Aeration tank to maintain the MLSS level whereas the clarified effluent is used in washing at B2 Thickner, Decker and Raw-Material quenching and gardening while remaining is discharged into the drain.
Wet washing effluent generated by washing of Raw-Material is passed through Rifflers and then is pumped to two Clarifiers, from there clarified Water is recyled in Wet Washing loop.
Make up of it is done by Kraft treated effluent which is passed through another Wet Washing recycling System having Primary, Aeration and Secondary, excess Water if any is taken to ETP. Sludge of all four Clarifiers is taken to Belt Press.
OThe Primary, Secondary Sludge and Wet Washing Sludge is taken to Belt Press where consistency is raised from 2.0% to 28 - 30% in semi solid form and disposed off to Board making units through Contractor.
After oxidation/degradation of organic matter in the Aeration tank the effluent overflows into the Secondary Clarifier. Secondary Clarifier facilitates the settling of excess Biomass which is recirculated into the Aeration tank to maintain the MLSS level whereas the clarified effluent is used in washing at B2 Thickner, Decker and Raw-Material quenching and gardening while remaining is discharged into the drain.
ETP Sludge is used for making Bricks (sold through Contractors).
Ash generated in Power Boiler are being sold through Contractors
and is used as low quality fuel.
Lime Sludge generated in Soda Recovery process is used for Bricks manufacturing which are now developed by collaborating with CBRI and IIT, Roorkee.