Advertisements
Advertisements
Question
Explain the role of microbes in sewage treatment.
Solution
Microbes play a significant role during secondary and tertiary sewage treatment.
- During secondary treatment, primary effluent is continuously agitated in a large tank due to which vigorous growth of useful aerobic microbes into flocs takes place. These microbes consume major part of the organic matter in the effluent as they grow. Due to this, BOD of the effluent is significantly reduced.
- During tertiary treatment, bacterial flocs are allowed to sediment. Small part of it is passed back into the aeration tank and a large part is pumped into large tanks called anaerobic sludge digesters. These anaerobic bacteria digest the bacteria and fungi in sludge.
- Thus, use of microbes in sewage treatment helps to remove organic matter from waste water before it is discharged in water bodies like rivers.
APPEARS IN
RELATED QUESTIONS
Explain the function of “anaerobic sludge digester” in a sewage treatment plant.
Explain the process of sewage water treatment before it can be discharged into natural water bodies.
Three water samples namely river water, untreated sewage water and secondary effluent discharged from a sewage treatment plant were subjected to BOD test. The samples were labelled A, B and C; but the laboratory attendant did not note which was which. The BOD values of the three samples A, B and C were recorded as 20mg/L, 8mg/L and 400mg/L, respectively. Which sample of the water is most polluted? Can you assign the correct label to each assuming the river water is relatively clean?
Which of the following occurs during tertiary treatment?
In the process of biogas production which of the following anaerobic bacteria are used?
Nitrogen fixation by organisms requires conditions that are:
During sewage, treatment biogas is produced wits which include:
The primary treatment of waste water involves the removal of ______.
Why is aerobic degradation more important than anaerobic degradation for the treatment of large volumes of waste waters rich in organic matter. Discuss.
The aeration tank of a sewage treatment plant is not functioning properly. Explain in detail the impact of this on the treatment of sewage and BOD of the effluent.