The process of Packaged STP is depending of characteristic of sewage however we are describing the typical process of Package STP in follows:
Sewage initially enters the primary settling tank. The tank incorporates specially designed Tube Settler Media, which reduces the suspended solids by 75% and the BOD by 25%. This zone is maintenance-free as it contains no moving parts.
The clarified effluent then enters the bio-reactor, which has an attached growth media like SAFF or FAB media and fine bubble diffuser membranes placed at the bottom of the tank. The SAFF / FAB media provides a large surface area for micro-organisms to attach themselves. These micro-organisms feed on the organic matter present in the effluent. The air bubbles help in thorough mixing of the liquid in the tank, besides providing vital oxygen.
The treated effluent then moves to the secondary settling tank. This tank incorporates specially designed Tube Settler Media for setting finer particles.
Sludge pumps are provided to remove sludge from the settling tanks and transfer it to Sludge Drying beds or a sludge de-watering device like a filter press.
The optional Tertiary Treatment includes equipment like chlorination for dis-infection and Multigrade Sand Filter & Activated Carbon Filter for removal of residual suspended solids, traces of organic materials, color and chlorine.
Packaged STP can applicable for below areas
- Packaged STP for Residential Building
- Packaged STP for Commercial Industries
- Packaged STP for Hotels and Motel
- Packaged STP for Restaurants
- Packaged STP for Schools, College and University
- Packaged STP for Pubs
- Packaged STP Food courts and Beverage Industry
- Packaged STP Malls
- Packaged STP for all other industries
Solid Separation Zone :
First stage transforms the influent solids to settled solids while allowing scum to float on the surface. It is a primary sedimentation zone in which settled sludge is stabilized by anaerobic digestion. The treatment efficiency of the chamber is in the range of 30 % BOD removal.
Second stage is the aerobic zone along with plastic media installed inside the tank which in turn increases the surface area and retain micro-organism long enough to digest the organic substance remained. Clear water will overflow the next treatment chamber. Air is provided through blowers and more contacting time with the slime on the plastic media, occurred, more efficient the digestion process would be. BOD removal is around 60-65%
Final Sedimentation Zone:
Final stage involves the sedimentation where organic wastes are settled in the Sedimentation zone. The settled waste in the bottom of the tank is pumped back to the primary sedimentation zone as a return sludge having active biomass (MLSS) to increase the efficiency of the system and ensure the effluent quality meets the stipulated standards.