Introduction to Wastewater Treatment (book) Part 4

Modern ponds usually consist of ____ or more separate ponds or cells

3 or more

What is meant by ponds being in series or parallel?

Series operations means one at a time

Parallel means side by side

Instead of mechanical aeration ponds rely on __ and __ to supply oxygen

Wind and algae

Wastewater may stay in a pond for as little as — days or longer than __ days.

As little as 12 days or longer than 180 days.

With activated sludge, the wastewater can remain in the tank for __ to __ hours

6 to 24 hours

What is the mix of bacteria and other microorganisms “bugs” called?

Mixed liquor suspended solids MLSS

What is Bioflocculation?

Uses a combination of flocculation and biological conversion and growth to make smaller particles into larger particles

What % of municipal sewage is water and how much is impurities?

99.9% water

0.1% impurities

What % of seawater is pure water and how much is impurities?

96.5% pure water

3.5% impurities (35000 mg/L)

How much BOD does domestic sanitary sewage have?

how much TSS?

200 mg/L of BOD

240 mg/L of TSS

Raw sanitary sewage typically has ___ mg/L of N

and ___ mg/L of P

35 mg/L of Nitrogen

10 mg/L of Phosphorus

The amount of pathogens is expected to be proportional to the concentration of ________

Fecal coliforms