Wastewater Treatment MCQ with answer and solution

Concept

Aerobic Biological Attached Growth Process

Formula

N/A

Step-by-step solution

1. Read the question regarding the primary function of the aerobic biological attached growth process in wastewater treatment. 2. Recall that oxygen-using bacteria absorb organic waste and convert it into settleable bioflocs and stable inorganic matter. 3. Select Option A as the correct choice.

Explanation

In an aerobic biological attached growth process (like a trickling filter), helpful bacteria and microorganisms grow as a fixed film (biofilm) on a solid material. As wastewater flows over this surface, these oxygen-using bacteria absorb dissolved and floating organic pollution. They consume this waste, converting it into heavy clumps of microbial mass (settleable bioflocs) that easily sink and separate, along with stable, non-harmful inorganic compounds like carbon dioxide and water.

Shortcut

To easily remember the function of the Aerobic Biological Attached Growth Process, use the phrase "Attached = Biofilm to Biofloc": - Aerobic & Attached: Bacteria grow attached to a media surface (biofilm) using oxygen. - Organic to Settleable: Converts suspended organic waste into heavy, settleable bioflocs and stable inorganics.

Common mistake

A common mistake is selecting Option C by confusing aerobic biological processes with anaerobic processes, which produce methane (CH4) and carbon dioxide (CO2). Another frequent error is selecting Option B or D by confusing biological secondary treatment with primary physical treatment processes like sedimentation or screening.