16 - Exploitation of natural microbial communities in the treatment of sewage

What do solids in waste water cause?

Silting of rivers

What are examples of toxic substances in waste water?

NH3 / heavy metals

What is BOD used to predict?

Effect of discharging waste / determine effectiveness of purification

By law, BOD must not exceed_______?

20mgL^-1

What equation is occurring at anaerobic digesters?

Organic matter -> CH4 + CO2 + H2O

What is the equipment for anaerobic digesters?

Incubation in sealed stirred tanks reactor at 35 degrees

What are the 2 secondary treatments?

Percolating filtration treatment / activated sludge process

What is formed on surface of clinker?

Biofilm of microbes

Tertiary processing:

Consist of filter through sand or pumping into enclosed reed bed prior to release into rivers.

Percolating filtration treatment / activated sludge process - which ones faster?

activated sludge process