Water Recycling
Trending Questions
Q. Study the following statements and select the incorrect ones.
(i) Physical removal of large and small particles through filtration and sedimentation is called primary sewage treatment.
(ii) Secondary sewage treatment is mainly a mechanical process.
(iii) Activated sludge sediment in a sewage treatment plant is a rich source of aerobic bacteria.
(iv) Biogas, commonly called as gobar gas, is pure methane.
(i) Physical removal of large and small particles through filtration and sedimentation is called primary sewage treatment.
(ii) Secondary sewage treatment is mainly a mechanical process.
(iii) Activated sludge sediment in a sewage treatment plant is a rich source of aerobic bacteria.
(iv) Biogas, commonly called as gobar gas, is pure methane.
- A-(iii), B-(i), C-(iv), D-(ii)
- A-(iii), B-(ii), C-(iv), D-(i)
- A-(iii), B-(i), C-(ii), D-(iv)
- A-(i), B-(iii), C-(iv), D-(ii)
Q.
Name any two forms in which calcium carbonate is found in nature.
Q. What will happen if a fresh water fish is kept in sea water and why?
Q.
Measurement of water pollution is made by
Coliform count
BOD
pH
All the above
Q. Which organisms are present in the euphotic zone?
Q.
What is the bod a measure of?
Q. Study the given differences between primary sludge and activated sludge and select the incorrect ones.
| Primary Sludge | Activated sludge | |
| (i) | It is sludge formed during primary sewage treatment. | It is sludge formed during secondary sewage treatment. |
| (ii) | It possesses flocs of decomposer microbes. | It does not possess flocs of decomposer microbes. |
| (iii) | It does not require aeration. | Formation of activated sludge requires aeration. |
| (iv) | A lot of decomposition occurs during formation of primary sludge. | Very little decomposition occurs during formation of activated sludge. |
- (i) and (ii)
- (ii) and (iv)
- (ii) and (iii)
- only (iv)
Q. Distinguish between roles of flocs and anaerobic sludge digesters in sewage treatments.
Q. What are the flocs use in the secondary sewage treatment?
Q. Explain the different steps involved during primary treatment phase of sewage.
Q. What is primary treatment of sewage?
Q.
_______is the chemical added to water to remove the tiny suspended particles.
Q.
Write true or false for the following statement:
“Alum is commonly used for removing suspended impurities.”
- True
- False
Q. Name the two different categories of microbes naturally occurring in sewage water. Explain their role in cleaning sewage water into usable water.
Q. Explain the steps involved in the sewage treatment.
Q. Explain the process of sewage water treatment before it can be discharged into natural water bodies. Why is this treatment essential?
Q. The primary treatment of sewage water involves
- Sludge digestion.
- Filtration and sedimentation.
- Aerobic bacterial activity.
- Anaerobic bacterial activity.
Q. During waste water treatment, trickling filter is used for
- Primary treatment
- Secondary aerobic treatment
- Tertiary treatment
- Secondary anaerobic treatment
Q. Sewage purification is performed by
- Microbes
- Fertilisers
- Antibiotics
- Antiseptics
Q. In the treatment of waste water discharge, which treatment stage involves biological treatment?
- Primary treatment
- Secondary treatment
- Tertiary treatment
- Reverse osmosis stage
Q. Which is correctly matched?
1. Arsenic poisoning- Black foot disease.
2. Secondary Effluent treatment- Biological process.
3. Pyrolysis- Solid soil waste disposal
4. Tubifex- Water pollution indicator
5. Biomagnification- Degradable pollutants
1. Arsenic poisoning- Black foot disease.
2. Secondary Effluent treatment- Biological process.
3. Pyrolysis- Solid soil waste disposal
4. Tubifex- Water pollution indicator
5. Biomagnification- Degradable pollutants
- 1, 2, 3, 5
- 1, 3, 4, 5
- 2, 3, 4, 5
- 1, 2, 3, 4
Q. In our municipal drinking water, under purification and supply scheme, chlorine is added to water because
- Chlorine gives sweat taste to water.
- Chlorine kills harmful bacteria.
- Chlorine cools water.
- Chlorinated water is now a days fashionable.
Q. What is activated sludge?
Q. During the primary treatment of sewage, solid particles that settle down are called
- Primary sludge
- Activated sludge
- Anaerobic sludge
- Flocs
Q.
is used to disinfect drinking water.
Q. Which of the following could be used in purification of sewage?
- Fungi
- Mycoplasma
- All plants
- Unicellular green algae
Q. Effluent from the primary treatment of sewage is passed for secondary treatment. Explain the process till the water is ready to be released into natural water bodies.
Q.
The rate of sedimentation is decreased by loading.
- True
- False
Q.
What purpose is the sedimentation process used for?
Q. One of the method for purification of water is sedimentation.
- True
- False
