Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
40 Cards in this Set
- Front
- Back
|
The maintenance of a good growth of organism on the filter media is crucial to successful trickling filter operation. T or F |
True |
|
|
Trickling filters separate the solids from the wastewater by a straining action. T or F |
True
|
|
|
Higher trickling filter loadings and greater efficiency are possible in warmer climates if aerobic conditions can be reasonably maintained in the filter. T or F |
True |
|
|
The hydraulic loading applied to a trickling filter is the total volume of liquid, including recirculation, expressed as GPD/sq ft. T or F |
True |
|
|
High-rate trickling filter loadings may be lower for synthetic media. T or F |
False
|
|
|
When you have checked out all equipment mechanically, starting up the trickling filter portion of the plant is very simple. T or F |
True
|
|
|
Slime growth on trickling filter media may be accelerated by recirculating wastewater through the trickling filter prior to treating the main wastewater flow stream. T or F |
True |
|
|
Operation of clarifiers is interconnected with trickling filter operation. T or F |
True |
|
|
When increasing the recirculation rate on a trickling filter, be sure the hydraulic laoding remains within the engineering design limits. T or F |
True |
|
|
For each incoming 100 pounds of BOD entering a trickling filter treatment plant, their should be at least five pounds of ammonia nitrogen and on pound of orthophosphate. T or F |
True |
|
|
Since operation of trickling filters is an aerobic process, serious odors are likely to exist. T or F |
False
|
|
|
Good grounds maintenance and cleanup practices will help to minimize fly problems. T or F |
True
|
|
|
Trickling filters respond quickly to operational changes. T or F |
False |
|
|
Trees should be planted close to open filters to provide shade. T or F |
False |
|
|
What is the purpose of trickling filter distributor bearings? 1. Allow air to flow through the media 2. Allow the distributor arms to rotate 3. Convey wastewater to outlet orifices located along the arms 4. provide a large surface area upon which the biological slime growth develops |
Allow the distributor arms to rotate |
|
|
What is the purpose of trickling filter media? 1. Allow air to flow through the media 2. Allow the distributor arms to rotate 3. Convey wastewater to outlet orifices located along the arms 4. Provide a large surface area upon which the biological slime growth develops |
Provide a large surface area upon which the biological slime growth develops |
|
|
Where trickling filter use recirculation, an additional organic (BOD) loading will be placed on the filter. Why is this added loading omitted in most calculations? 1. Because it does not accurately reflect the additional organic loading 2. Because it fluctuates over a wide range in recirculated flows 3. Because it is difficult to measure in recirculated flows 4. Because it was included in the influent load |
Because it was included in the influent load |
|
|
How can some of the unexpected, frustrating problems encountered during the start-up of a new plant be avoided? 1. By awarding the project to a low-bid contractor 2. By careful inspection ahead of time 3. By cutting costs during the planning and design phases 4. By excluding operator participation during the review of plans and specifications and the construction phase |
By careful inspection ahead of time |
|
|
The ability of a operator to correct deficiencies in trickling filter performance will depend on which factors? 1. The operator's ability to network with other operators and regulatory inspectors 2. The operator's alertness and ingenuity, as well as the design of the collection system and treatment plant 3. The operator;s knowledge of plant construction techniques and options 4. The operator's participation in a continuing education program |
The operators alertness and ingenuity, as well as the design of the collection system and treatment plant |
|
|
Rapid changes in the influent load to a trickling filter plant can best be estimated by using which test? 1. BOD test 2. COD test 3. Chlorine residual test 4. Coliform bacteria test |
COD test
|
|
|
What is the main indicator of how effectively a trickling filter plant is working? 1. Chlorine residual 2. Charity 3. Plant effluent 4. Plant influent |
Plant effluent |
|
|
In the operation of trickling filters, which item could cause serious odors? 1. Excessively high hydraulic loadings 2. Flow of air through the media 3. Odor-producing compounds present in the wastewater in high concentrations 4. Prolonged aerobic conditions
|
Odor-producing compounds present in the wastewater in high concentrations |
|
|
What should be checked when the trickling filter treated effluent quality is poor? 1. Diameter of the distributor base 2. Organic load on the filter 3. Size distribution of the media 4. Spacing of the ventilation ports |
Organic load on the filter |
|
|
Why should the turnbuckles be adjusted occasionally on the guy rods of a trickling filter? 1. To keep the orifices on the rotating distributor from plugging 2. To keep the rotating distributor arms at the proper level to provide even flow over all of the media 3. To keep the rotating distributor rotating in a circular motion 4. To prevent ponding on the surface of the filter |
To keep the rotating distributor arms at the proper level to provide even flow over all of the media |
|
|
When reviewing plans for a new trickling filter plant with respect to overhead clearance, what should operators check? 1. Distance from floor to ceiling in pump rooms will provide adequate ventilation 2. Electrical power and telephone lines will not interfere with any equipment 3. Headroom for stationary equipment will be cost effective 4. Height of doors will not cause head bumps and bruises |
Electrical power and telephone lines will not interfere with any equipment |
|
|
*What is the purpose of secondary treatment? To remove 1. Dissolved solids 2. Grit 3. Scum or floatable solids 4. Settleable solids 5. Very small suspended solids (colloids) |
Dissolved solids and very small suspended solids |
|
|
*Clogged void spaces in trickling filters can create which operational problems? 1. Decrease in chlorine requirements 2. Decrease in recirculation 3. Greater microorganism activity in the zoogleal film 4. Ponding 5. Reduction in overall filter efficiency |
Ponding and reduction all overall filter efficiency |
|
|
*What are the benefits of recirculation and the resulting sloughing of excess or aged growths from trickling filter media? 1. Decrese the opportunity for snail and filter fly breeding 2. Improve ventilation through the filter 3. Increase the production of methane gas 4. Prevent ponding 5. Provide a more aggressive surface of new growths to treat the wastewater |
1, 2, 4, 5 |
|
|
*Which task should be performed by operators during the pre-start activities of a new trickling filter plant? 1. Be sure the correct oil and amount of oil are used in all oil reservoirs 2. Check the distibutor arms for even adjustment and level 3. Check the trickling filter carefully to be certain the essential parts will work properly when wastewater is applied 4. Record the amount and type of oil each reservoir holds 5. Remove the packing grease from the filter bearings and replace with the proper grease |
1, 3, 4, 5 |
|
|
*Why should trickling filter recirculation be done during low-inflow periods of the day and night? 1. To avoid clarifier problems from hydraulic overloading 2. To encourage the development of snail populations on the media 3. To keep the slime growths wet 4. To minimize filter fly development 5. To wash off excessive slime |
1, 3, 4, 5 |
|
|
*What trickling filter problems can result from recirculation rates that are too low? 1. Decrease in water conservation efforts 2. Increase in chlorine usage 3. Loss of solids over effluent weirs in the clarifiers 4. Ponding 5. Reduced BOD removal efficiency |
Ponding and Reduced BOD removal efficiency
|
|
|
*A trickling filter plant effluent that is high in suspended solids could be caused by which factors? 1. Anoxic conditions in the primary clarifier 2. Gasification (denitrification) caused by septic sludge in the secondary clarifier 3. Heavy sloughing from the filters 4. High hydraulic loading or short-circuiting through the secondary or final clarifier 5. Shock loading caused by toxic wastes or hydraulic or organic overloads |
2, 3, 4, 5 |
|
|
*An alert operator will note changes in process units by observing which physical factors in a trickling filter plant? 1. Amount of scum on a clarifier 2. Appearance of the effluent 3. Flow rate or height over weirs 4. Launder levels 5. Spray pattern |
1, 2, 3, 4, 5 |
|
|
*Minor ponding in a trickling filter can be eliminated by which methods? 1. Dose the filter with chlorine at about 5mg/L for several hours 2. Hand turn or stir the filter surface with a rake, fork, or bar 3. Remove any accumulation of leaves or other debris 4. Shut off the flow to the filter for several hours 5. Spray the filter surface with a high-pressure water stream |
1, 2, 5
|
|
|
*Which items are guidelines for maintaining trickling filters to prevent odor problems? 1. Check the ventilation in the trickling filter 2. Do everything possible to maintain aerobic conditions in the sewer collection system and in the primary treatment units 3. Increase the recirculation rate to provide more oxygen to the filter bed and increase sloughing 4. Keep the wastewater splash from the distributor away from exposed structures grass, and other surfaces 5. Provide a forced-air ventilation system and odor control of the exhaust air stream for covered filters |
1, 2, 3, 4, 5 |
|
|
*When are plant inflows considered abnormal? When there are... 1. Extreme levels of biochemical oxygen demand (BOD) 2. Extreme levels of suspended solids 3. Flows consistant with normal dry weather flows 4. High flow rates 5. Inflows of a septic influent
|
1, 2, 4, 5 |
|
|
*Which items are typical influent toxic conditions? 1. Excess amounts of ammonia 2. Excess amounts of heavy metals 3. Excess amounts of hydrocarbons 4. Excessively high or low levels of coliforms 5. Excessively high or low pH |
1, 2, 3, 5 |
|
|
*Which items are probable cause of trickling filter odors? 1. Anaerobic waste being applied to the filters 2. Excessive biological growths 3. Excessive hydraulic loads 4. Poor housekeeping 5. Poor ventilation of the filter |
1, 2, 4, 5 |
|
|
*Why should operators review plans and specifications for a new plant? 1. To become a contractor and construct new plants 2. To become familiar with the proposed plant 3. To learn how to design new plants 4. To learn what will be constructed 5. To offer suggestions on how the plant can be designed for easier and more effective operation and maintenance |
2, 4, 5 |
|
|
*When reviewing plans for a new plant, operators should carefully study which areas? 1. Budget 2. Equipment 3. Safety aspects 4. site 5. Trickling filter structure |
2, 3, 4, 5 |
