If the recirculation ratio is 1:1, how does the total flow to the trickling filter compare to the incoming flow?

If the recirculation ratio is 1:1, how does the total flow to the trickling filter compare to the incoming flow?

• A. Half
• B. Equal
• C. Twice
• D. Three times

Answer: (C)

The main idea is how recirculation affects the flow going into the trickling filter. The total flow to the trickling filter is the sum of the fresh incoming flow and the recirculated flow. If the recirculation ratio is 1:1, the amount recirculated equals the incoming flow. Therefore, the total flow to the trickling filter is incoming flow plus the same amount recirculated, i.e., twice the incoming flow. For example, with 500 units entering, 500 are recirculated, giving 1000 units to the filter.

The main idea is how recirculation affects the flow going into the trickling filter. The total flow to the trickling filter is the sum of the fresh incoming flow and the recirculated flow. If the recirculation ratio is 1:1, the amount recirculated equals the incoming flow. Therefore, the total flow to the trickling filter is incoming flow plus the same amount recirculated, i.e., twice the incoming flow. For example, with 500 units entering, 500 are recirculated, giving 1000 units to the filter.