Civil Engineering - Waste Water Engineering - Discussion

B is correct.

According to Spellman, The trickling filter does not provide any actual filtration. The filter media provides a large amount of surface area that the microorganisms can cling to and grow in a slime that forms on the media as they feed on the organic material in the wastewater.

The Answer is wrong. As Per Govt of India Manual, a number of books and International Source Book issued by United Nation of Environmental Programme, filtration also occurs in Trickling filter.

So the correct answer is D (Both).

I think Option D is correct.

Option D is correct.

D is the correct answer. I too agree.

I also agree it should be D as:

The process of filtration can be explained by certain theories as:

I) Mechanical straining÷ big suspended or dissolved particles get arrested in voids.

II) Flocculation and Sedimentation÷ voids act like tiny sedimentation tanks arrest the colloidal matter which forms a gel and arrest finer particles.

III) Biological metabolism ÷ microorganisms in the voids digest the bacteria as food
IV) Electrolytic changes ÷ filtration by the method of ion exchange.
So, both come true.

D is the correct answer.

As per the Burea of Indian standards, Metcalf and eddy, USEPA, trickling filter technology patents, Central pollution control board, CPHEEO manual, CSIR, old questions in UPSC, the trickling filter also have filtration processes in it.

So, the answer is D.