undertan1995
Civil/Environmental
- Jul 23, 2020
- 4
I'm involved in a project at a Wastewater Treatment Plant that involves relocating a gas chlorine feed system. It originally shared a building with the plant's MCC, but due to issues it needs to be separated and reside in its own building. The plant utilizes water from the chlorine contact tank for use throughout the different processes such as yard water, water for the clarifiers, and also for pressure supply to deliver the required amount of gas chlorine to the chlorine mixer. A portion of water is pumped out of the chlorine contact tank and throughout the plant. I was visiting the plant earlier this week and noticed that a pressure gauge on the hydropneumatic tank located just outside the chlorine room read 30 psi. I've also noted that the chlorine injector nozzle requiring the least amount of supply pressure for the backpressure and feed rate calculated is 35 psi. My question is this: Is it even possible to change the settings on the hydropneumatic tank (which control the start and stop of the pumps in the chlorine contact tank) to start pumps at a minimum of 35 psi and stop pumps at, say 40 psi? This is not how the system is operating and I suspect that the system head curve is currently intersecting the pump curve at approximately 30 psi (69 ft). 35 psi and 40 psi do fall well within the pump curve and even closer to the BOP. I'd prefer to do this rather than purchase a separate booster for the chlorine gas system. Thank you for reading this and entertaining my question.