WASTEWATER TREATMENT CLASS B
EXAM TEST PAPER QUESTIONS
SOLUTIONS GRADED A+
◉ What is a flow equalization used for? Answer: to reduce excessive
flows or organic loads
◉ How can grease be removed before sedimentation? Answer: by
chlorination, aeration and skimming
◉ A primary clarifier should remove most of what? Answer:
settleable solids
◉ What conditions can influence settling of solids? Answer:
temperature, condition of solids and flow velocity
◉ Sludge from a primary clarifier should have a moisture content of
what? Answer: 94-96%
◉ By performing Imhoff cone tests on the clarifier inlet and outlet,
the operator can determine what? Answer: the efficiency of the
clarifier and a sludge pumping schedule
,◉ When temperature increases, water becomes... Answer: less dense
◉ What problem is short-circuiting in a clarifier? Answer: flow
problem
◉ How should raw sludge be pumped to a digester? Answer: slowly
when it is adequately thickened
◉ In an Imhoff tank, the upper compartment serves as the... Answer:
clarifier
◉ In an Imhoff tank, the lower compartment serves as the... Answer:
digester
◉ Wastewater is treated by what organisms? Answer: bacteria,
fungi, algae, plants, animals and protozoa
◉ How many basic cell structures are there? Answer: 2
◉ What factors affect biological growth? Answer: dissolved oxygen
level, temperature, pH and available food
◉ What is the most important microorganism in wastewater
treatment? Answer: bacteria
, ◉ In what ways are bacteria classified? Answer: shape, oxygen
needs, temperature and metabolism
◉ In the removal process, what must bacteria do? Answer: gather
food, digest food, utilize food and give off by-products
◉ What limiting factors affect bacteria growth? Answer: pH,
temperature, moisture and food
◉ What must the operator control in order for microorganisms to do
their job? Answer: the environment
◉ What by-products are excreted by microorganisms? Answer: CO2,
H2O and NH3 and polysaccharides
◉ Treatment pond classifications are... Answer: wastewater
stabilization ponds, aerated lagoons, facultative lagoons, anaerobic
lagoons and hyacinth ponds
◉ What will a wastewater stabilization pond effectively reduce?
Answer: BOD and bacteria
◉ Anaerobic lagoon dissolved oxygen content... Answer: none
EXAM TEST PAPER QUESTIONS
SOLUTIONS GRADED A+
◉ What is a flow equalization used for? Answer: to reduce excessive
flows or organic loads
◉ How can grease be removed before sedimentation? Answer: by
chlorination, aeration and skimming
◉ A primary clarifier should remove most of what? Answer:
settleable solids
◉ What conditions can influence settling of solids? Answer:
temperature, condition of solids and flow velocity
◉ Sludge from a primary clarifier should have a moisture content of
what? Answer: 94-96%
◉ By performing Imhoff cone tests on the clarifier inlet and outlet,
the operator can determine what? Answer: the efficiency of the
clarifier and a sludge pumping schedule
,◉ When temperature increases, water becomes... Answer: less dense
◉ What problem is short-circuiting in a clarifier? Answer: flow
problem
◉ How should raw sludge be pumped to a digester? Answer: slowly
when it is adequately thickened
◉ In an Imhoff tank, the upper compartment serves as the... Answer:
clarifier
◉ In an Imhoff tank, the lower compartment serves as the... Answer:
digester
◉ Wastewater is treated by what organisms? Answer: bacteria,
fungi, algae, plants, animals and protozoa
◉ How many basic cell structures are there? Answer: 2
◉ What factors affect biological growth? Answer: dissolved oxygen
level, temperature, pH and available food
◉ What is the most important microorganism in wastewater
treatment? Answer: bacteria
, ◉ In what ways are bacteria classified? Answer: shape, oxygen
needs, temperature and metabolism
◉ In the removal process, what must bacteria do? Answer: gather
food, digest food, utilize food and give off by-products
◉ What limiting factors affect bacteria growth? Answer: pH,
temperature, moisture and food
◉ What must the operator control in order for microorganisms to do
their job? Answer: the environment
◉ What by-products are excreted by microorganisms? Answer: CO2,
H2O and NH3 and polysaccharides
◉ Treatment pond classifications are... Answer: wastewater
stabilization ponds, aerated lagoons, facultative lagoons, anaerobic
lagoons and hyacinth ponds
◉ What will a wastewater stabilization pond effectively reduce?
Answer: BOD and bacteria
◉ Anaerobic lagoon dissolved oxygen content... Answer: none
