A. Dissolved air prevents the backwash water from flowing through the media B. Excessive filter cracking occurs C. Mud ball formation is increased, making the filter unusable D. Media becomes suspended in the wash water and flows out of the filter 7. When a filter is operated to a head loss that exceeds the head of water over the media: A. Dissolved air will be released causing air binding B. Air will become dissolved and pass through the filter, causing high NTU readings C. The media will not reset itself after backwashing D. The filtration rates will be improved, allowing longer filter run times 8. Why does filtration typically follow PAC addition in a water treatment plant? A. Filters are necessary to provide the contact time for PAC to be effective. B. PAC creates turbidity which must be removed before distribution. C. Chlorine in the filters will deactivate the PAC. D. The PAC must be applied as a on the filter media for it to be effective. “cap” Reverse Osmosis / Desalination ________ of 4 questions 1. The "Christmas Tree" layout used in RO membrane staging allows for A. Up to 50% recovery of feedwater as product water B. 100% recovery of feedwater as concentrate C. 85% recovery of feedwater as product water D. Highest flux rate possible 2. The application of sodium hexametaphosphate to the feedwater of an RO membrane helps to A. Decrease the precipitation of organic matter on the membrane B. Increase the amount of flux rate C. Decrease the amount of calcium sulfate precipitation on the membrane D. Decrease the temperature and pH, allowing higher flux rates 3. The increasing tendency for precipitation of sparingly soluble salts and deposition of particulate matter on the membrane surface is called A. Compaction B. Concentration polarization C. Hydrolysis D. Demineralization 4. Why are acids commonly fed into the feedwater of an RO unit? A. To increase alkalinity
A. Dissolved air prevents the backwash water from flowing through the media B. Excessive filter cracking occurs C. Mud ball formation is increased, making the filter unusable D. Media becomes suspended in the wash water and flows out of the filter 7. When a filter is operated to a head loss that exceeds the head of water over the media: A. Dissolved air will be released causing air binding B. Air will become dissolved and pass through the filter, causing high NTU readings C. The media will not reset itself after backwashing D. The filtration rates will be improved, allowing longer filter run times 8. Why does filtration typically follow PAC addition in a water treatment plant? A. Filters are necessary to provide the contact time for PAC to be effective. B. PAC creates turbidity which must be removed before distribution. C. Chlorine in the filters will deactivate the PAC. D. The PAC must be applied as a “cap” on the filter media for it to be effective. Reverse Osmosis / Desalination ________ of 4 questions 1. The "Christmas Tree" layout used in RO membrane staging allows for A. Up to 50% recovery of feedwater as product water B. 100% recovery of feedwater as concentrate C. 85% recovery of feedwater as product water D. Highest flux rate possible 2. The application of sodium hexametaphosphate to the feedwater of an RO membrane helps to A. Decrease the precipitation of organic matter on the membrane B. Increase the amount of flux rate C. Decrease the amount of calcium sulfate precipitation on the membrane D. Decrease the temperature and pH, allowing higher flux rates 3. The increasing tendency for precipitation of sparingly soluble salts and deposition of particulate matter on the membrane surface is called A. Compaction B. Concentration polarization C. Hydrolysis D. Demineralization 4. Why are acids commonly fed into the feedwater of an RO unit? A. To increase alkalinity