Water and Wastewater micro Flashcards
what is the basis for waste water treatment
Microorganisms are sued to remove organic mater from used water
these microorganisms work to reduce the toxicity of poisonous substances in the water
the levels of contaminate should be lowered to a point of which natural processes are capable to removing the rest
what are the levels of waste water treatment
Primary
secondary
tertiary
What is Primary Treatment
Includes physical separation of large debris
sewage solids
What is secondary treatment
Used to reduce the organic load
both anoxic or aerobic
Anoxic secondary treatment
series of digestive and fermentative reactions
Sludge digestors or bioreactors support growth of anaerobic bacteria
high production of both methane or carbon dioxide
Aerobic secondary treatment
Trickling filter and activated sludge systems
mineralization of organic matter to carbon dioxide, ammonia, nitrate, sulfate and phosphate
Tertiary treatment
uses both physical and chemical processes such as filtration and chlorination which reduces compounds such as phosphate and nitrate which may be present in the water
what does water treatment focus on?
Production of potable water
what are the 3 main stages of drinking water treatment
sedimentation
filtration
Disinfection
sedimentation
removal of sand gravel and other larger particles(enhanced flocculation/coagulation)
80% of bacteria are removed at this stage
filtration
removes suspended particles and microorganisms(very important for removal of protozoan cysts
approximately 89-99.5% of microorganisms removed in this step
Disinfection
main purpose is to ensure protection against post treatment contamination (disinfectant residual) uses chlorination
indicator organisms
associated w the intestinal tract thus presence could indicate fecal contamination (coliform bacteria which for example are E.coli)
