Activated Sludge and Aerobic Digestion Flashcards
The treatment given to settled wastewater in an aeration tank is accomplished by…
The organisms living in the activated sludge that use the organic matter for food and convert it to a less objectionable condition
The term “bioprecipitation,” which describes a process in wastewater treatment, may properly be applied to…
The activated sludge process
The term “activated sludge” refers to…
The brownish flocculant of culture of organisms developed in an aeration tank under controlled conditions
The aeration and oxidation of wastewater is accomplished most effectively by…
Introducing compressed air at one side and near the bottom of tanks through which the wastewater flows
Mixed liquor is…
A mixture of primary effluent and RAS flowing into an aeration tank
The bacteria used in the activated sludge process…
Are normally present in any domestic wastewater
In a conventional activated sludge plant, the purpose of returning sludge to the aeration tank is to…
Maintain a satisfactory biological population
Which of the following is a modification of the activated sludge process?
Aerated lagoons, contact stabilization, activated carbon filters, wet oxidation
Contact stabilization
The Kraus process is sometimes used in connection with…
The activated sludge process
One of the differences between extended aeration and the conventional activated sludge system is…
The presence or absence of a primary tank
The air introduced into wastewater in the aeration tank of an activated sludge plant serves mainly to…
Agitate the mixture and provide oxygen for the organisms present in the activated sludge
The solution to bulking sludge in the secondary clarifier is…
Increase DO in aeration tank and sludge return rate
The solution to rising sludge in the secondary clarifier is…
Increase DO in aeration tank and sludge return rate
The solution to pinfloc in the secondary clarifier is…
Increase DO in aeration tank and sludge wasting
What action should be taken if there is thick white foam on an aeration tank?
Decrease sludge wasting
