front 1 Greensand treated with Potassium Permanganate is used to remove ______ from water? | back 1 Iron and manganese |
front 2 An iron bacteria that will oxidize iron in water and use the energy for reducing carbon dioxide to organic forms is a? | back 2 Crenothrix, Thiothrix |
front 3 What is the best method to test for iron in the water? | back 3 Atomic Absorption (AA) |
front 4 When testing for iron, if there is clay or visible rust you should not ______ the sample? | back 4 Acidify, Also, ask lab to analyze immediately |
front 5 Polyphosphate should always be added to the water prior to? | back 5 Chlorine |
front 6 Never use a polyphosphate over ______ old? | back 6 48 hours |
front 7 A WTP using polyphosphate to control iron corrosion is getting calls because of red water in the distribution system. What is the likely cause of the red water? | back 7 Ans. Iron Bacteria |
front 8 Soluble iron can be oxidized to insoluble precipitates by ______ and removed by sedimentation & filtration? | back 8 Ans. Chlorine |
front 9 When using aeration to oxidize Iron from the water, increasing the ______ will improve the removal efficiency? | back 9 pH |
front 10 What chemical is commonly used to dechlorinate large amounts of water? | back 10 Sodium Bisulfite |
front 11 Potassium Permanganate is used with ______ to remove iron and manganese from water. | back 11 Greensand Filtration |
front 12 What is used to regenerate a manganese greensand filter? | back 12 Permanganate (KMnO₄) |
front 13 What causes pink water? | back 13 Overdose of KMnO₄ |
front 14 A WTP with greensand treatment is receiving red water complaints from its customers. What is the likely cause? | back 14 Ans. Iron Bacteria |
front 15 Electromedia iron and manganese removal systems use what chemical to remove sulfur compounds causing taste and odor problems? | back 15 Small dose of sulfur dioxide |
front 16 The influent to a manganese greensand filter has a pinkish/orange color. What does this indicate? | back 16 Normal and will be removed by the filter |
front 17 A pink color in the greensand filter effluent indicates? | back 17 Overdose of KMnO₄ |
front 18 Greensand filter effluent has a yellow to brownish color. Effluent has high iron and manganese content. What is the problem? | back 18 High Alkalinity |
front 19 How would you correct the problem in question 18? | back 19 Reduce alkali feed; maintain pH during Cl₂, addition between 6.2-6.5. |
front 20 How would you get rid of the red water that is in the distribution system? | back 20 Flush fire hydrants |
front 21 Filter effluent clear, iron level low, and manganese level higher than raw water. What is the most likely cause? | back 21 Manganese leaching from greensand; bed is insufficiently regenerated |