Question

Microbes are involved in which step(s) of wastewater treatment?

A) primary only
B) secondary and tertiary
C) secondary only
D) primary and secondary

Answer 1

Microbes are involved in the secondary and tertiary steps of wastewater treatment.

Step-by-step explanation:

The involvement of microbes in wastewater treatment occurs in the secondary and tertiary steps of the process. In the secondary treatment, microorganisms, specifically aerobic bacteria, are used to decompose the dissolved and suspended organic matter in the wastewater. This can be done through activated sludge systems or fixed film systems, where bacteria grow on filters.
The tertiary treatment also involves the use of bacteria to decompose nutrients and further filter the water before it is discharged or reused for other purposes.