Velocity is an important consideration in wastewater collection and treatment systems. What is the desired velocity of flow in gravity sewers and grit channels and why? At municipal wastewater treatment plants, primary clarifiers remove what percentage of settleable solids, BOD, and total suspended solids? How is percent removal of a pollutant across a unit process […]
Hydraulic loading in a treatment pond is always given in what units? Organic loading to a treatment pond is always given in what units? Is ft²/s units of flow? There are approximately how many Mgal in a pond 1 ac in area operated at a depth of 3 ft? Why does the solution bridge “work?”
What does “VSR” stand for? If the VSR in an anaerobic digester is found equal to 56%, how does WWTT recommend it be expressed for gas problems? What makes the relationship between two or more organisms symbiotic? The presence of what gas causes the pH in a wastewater treatment pond to go up and down? […]
If VS in anaerobic digesters are not really “reduced” or “destroyed,” what happens to them? What is the primary function of a secondary digester? Why is safety equipment needed in the gas piping from an anaerobic digester? Pressure and vacuum relief devices are necessary to protect the structural integrity of an anaerobic digester. What units […]
If carbon dioxide is non-flammable, non-explosive, odorless, not toxic, how can it kill you? What is the composition of digester gas? True or false: A DAFT is a dewatering unit process. In equation format, what is the relationship between flow (Q), area (A), and velocity (v)? The density of water is used in wastewater calculations […]
What is the difference between fixed solids and volatile solids? How does the wastewater treatment profession define total suspended solids (TSS)? True or false: Hydrogen sulfide is a major component of digester gas. What characteristics of hydrogen sulfide—name three—make it particularly dangerous (and potentially lethal)? When is methane mixed with air explosive?
Describe a typical diurnal flow pattern to a municipal wastewater treatment plant. In the BOD test organic strength is measured indirectly. What is directly measured in this test from which organic strength is inferred? List one advantage and one disadvantage of the COD test in comparison to the BOD test. Carbon dioxide dissolved in water […]
List five analyses that can only be done on grab samples. True or false: A combined sewer conveys domestic and hospital wastes. Explain how infiltration increases after a heavy rain. List three different types of collection systems. Composite samples can be collected two ways. What are they?
Total solids (TS) can be divided two ways. What are they and what results from these two divisions? True or false: All settleable solids are total suspended solids. True or false: All TSS are settleable. What percent, approximately, of raw sewage is pure water? What does hydrogen sulfide smell like?
Wastewater treatment plants are charged two costs by the local power company. What are they and what are the units of each? How is the density of a liquid calculated if the specific gravity is given? If an acre is a unit of area, an ac.ft is a unit of what? Why does the solution […]