SEWAGE TREATMENT PLANTS (STP)
A sewage treatment plant is the type of plant that you would find in a typical urban area or big city. The primary purpose of an STP is to remove contaminants from household wastewater through several arduous processes. A treatment plant will also clean rainwater that gathers in storm sewers, and in some cases also receive sewage from commercial buildings. After being thoroughly treated, the water is safe to reuse in the outside world!
ACTIVATED SLUDGE PLANTS (ASP)
An activated sludge plant can be a simpler more cost-effective option to an STP, depending on the circumstances. It’s name comes from the method used to treat the water: activated sludge. This method primarily attacks biological contaminants in the water. It’s worthwhile to note, however, that an STP may also use activated sludge along with other processes as part of wastewater treatment.
EFFLUENT TREATMENT PLANTS (ETP)
These sewage treatment plants focus on industrial wastewater from large companies. Companies that are involved with pharmaceuticals or chemical manufacturing produce wastewater that can contain toxic chemicals, other non-toxic materials and cause pollution. Because of the extensive nature of the sewage treatment processes needed, ETPs are best suited to large operations, not small.
COMMON & COMBINED EFFLUENT TREATMENT PLANTS (CETP)
Even though they can’t afford the expense of an ETP, smaller companies still need wastewater treatment. That’s where combined treatment plants come in! A CETP is designed to help small-scale industries save money by pooling wastewater (or effluent) in one plant for treatment. Those who share the facility also share the cost of its upkeep, effectively reducing expenses and the stress of maintaining such a large operation.