Search results
Results from the WOW.Com Content Network
Sewage treatment plant (a type of wastewater treatment plant) in La Crosse, Wisconsin. Wastewater treatment is a process which removes and eliminates contaminants from wastewater. It thus converts it into an effluent that can be returned to the water cycle. Once back in the water cycle, the effluent creates an acceptable impact on the environment.
Sewage treatment plants can have significant effects on the biotic status of receiving waters and can cause some water pollution, especially if the treatment process used is only basic. For example, for sewage treatment plants without nutrient removal, eutrophication of receiving water bodies can be a problem.
In water treatment plants, backwashing can be an automated process that is run by local programmable logic controllers (PLCs). The backwash cycle is triggered after a set time interval, when the filter effluent turbidity is greater than a treatment guideline or when the differential pressure ( head loss ) across the filter exceeds a set value.
A goal of the wastewater purification by means of AOP procedures is the reduction of the chemical contaminants [7] and the toxicity to such an extent that the cleaned wastewater may be reintroduced [8] into receiving streams or, at least, into a conventional sewage treatment.
The RBC process allows the wastewater to come in contact with a biological film in order to remove pollutants in the wastewater before discharge of the treated wastewater to the environment, usually a body of water (river, lake or ocean). A rotating biological contactor is a type of secondary (biological) treatment process.
This contaminated water can be disposed of, along with the sludge from the sedimentation basin, or it can be recycled by mixing with the raw water entering the plant although this is often considered poor practice since it re-introduces an elevated concentration of bacteria into the raw water. Some water treatment plants employ pressure filters.
This is why low speed surface aerators are mostly used in sewage or industrial treatment as WWTP [clarification needed] are bigger and sparing energy becomes very interesting. Biological oxidation processes are sensitive to temperature and, between 0 °C and 40 °C, the rate of biological reactions increase with temperature.
Three wastewater/sewage clarifiers at the ʻAikahi wastewater treatment plant in Hawaii. They appear to have a floating cover [dubious – discuss] to reduce the odor because the plant is very close to a residential area. Circular clarifier with surface skimmer visible in the lower right.