WASTEWATER
By Rick Lallish
Which type of blower may not be operated against a closed valve?
A. Centrifugal
B. Positive displacement
C. High-speed driven (turbo)
D. Open-impeller single-stage
Answer: B. Blowers and pumps have similar characteristics. Positive displacement blowers, like positive displacement pumps, may never be operated against a closed valve. If so, damage will occur to the piping, valves and possibly the blowers. This is an unsafe condition that may cause bodily harm to personnel nearby. Only centrifugal or like blowers may be operated in this manner. More information may be found in the WEF textbook Wastewater Treatment Fundamentals II – Solids Handling and Support Systems, Chapter 8.DRINKING WATER
By Drew Hoelscher
How
