This set of Waste Water Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Ion Exchange Process”.
1. Ion exchange units are known as ______
a) Water hardeners
b) Water softeners
c) Water purifiers
d) Exchangers
View Answer
Explanation: Ion exchange units that replace calcium and magnesium ions from water are known as water softeners. They may also remove varying amounts of other inorganic pollutants such as metals.
2. Water softener units work most efficiently with particulate water.
a) True
b) False
View Answer
Explanation: Water softener units work most efficiently with particulate-free water. Ion exchange units that replace calcium and magnesium ions from water are known as water softeners.
3. Which of these have a negative electrical charge?
a) Calcium
b) Magnesium
c) Sodium
d) Chloride
View Answer
Explanation: Calcium and magnesium ions are atoms having a positive electrical charge, as do sodium and potassium ions. Ions of the same charge can be exchanged.
4. The ions with opposite charge can be exchanged.
a) True
b) False
View Answer
Explanation: Ions of the same charge can be exchanged. In the process, the water containing calcium and magnesium ions is considered and substance containing sodium or potassium ions is used against it.
5. While designing the demineralisation plant what is considered as the weak acidic cation load?
a) Alkaline hardness
b) Alkaline hardness+ EMA
c) EMA
d) Silica
View Answer
Explanation: The load for Weak acid cation is alkaline hardness alone. Alkalinity is expressed as phenolphthalein alkalinity. It is also expressed as methyl orange alkalinity.
6. While designing the demineralisation plant what is considered as the strong acidic cation load?
a) Alkaline hardness
b) Alkaline hardness + EMA
c) EMA
d) Silica
View Answer
Explanation: The load for Weak acid cation is alkaline hardness alone. This is also equivalent to total anions. Total anions is equivalent to alkaline hardness + EMA.
7. While designing the demineralisation plant what is considered as the strong basic anion load?
a) Alkaline hardness
b) Alkaline hardness + EMA+CO2
c) EMA+Silica
d) Silica+CO2+ Alkalinity+EMA
View Answer
Explanation: The load for strong basic anion is Silica+CO2+ Alkalinity+EMA. This is in the case where there is no degasser.
In case there is a degasser then the CO2 load is not considered.
8. While designing the demineralisation plant what is considered as the weak basic anion load?
a) Alkaline hardness
b) Alkaline hardness + EMA
c) EMA
d) Silica
View Answer
Explanation: The load for weak basic anion is EMA alone. EMA constitutes of chlorides, sulphides, nitrates etc. It is the sum total of these ions.
9. When is strong basic anion not necessary?
a) Silica is nil
b) CO2 is nil
c) Fluroine is nil
d) Sulphate is nil
View Answer
Explanation: When silica is nil, there is no requirement of a strong basic anion. Degasser removes CO2. A degasser tower is used in such cases.
10. When the hardness and alkalinity are around 30% what should be used?
a) SAC
b) WAC
c) WAC, SAC
d) WAC, SAC, WBA
View Answer
Explanation: When the hardness and alkalinity are around 30%, then WAC and SAC should be used. WAC removes temporary hardness caused by alkalinity. SAC removes EMA and alkalinity.
11. In case along with silica, there is high content in sulphide and chloride what should be used?
a) WBA
b) WBA and SBA
c) SBA
d) SBA,WBA and WAC
View Answer
Explanation: In case the sulphide and chloride are present then WBA should be used. SBA removes only silica and alkalinity. It doesn’t remove EMA.
12. What is the preferred regenerant in case of cation exchanger?
a) HCl
b) H2SO4
c) H2CO3
d) HF
View Answer
Explanation: The preffered regenerant in case of cation exchanger is HCl. Regeneration is a process necessary to regenerate the resin. In this way the resin can be reused for the next demineralization process.
13. What is the preferred regenerant in case of anion exchanger?
a) NaCl
b) NaOH
c) Na2SO4
d) Na2CO3
View Answer
Explanation: The preffered regenerant in case of anion exchanger is NaOH. Regeneration is a process necessary to regenerate the resin. In this way the resin can be reused for the next demineralization process.
14. For obtaining Silica<5 ppm which of these should be utilized?
a) SBA followed by Mixed be
b) SBA
c) WBA SBA followed by mixed bed
d) Mixed bed
View Answer
Explanation: A mixed bed is usually followed after a SBA to obtain silica level < 5 ppm. Mixed bed constitutes both an anion and cation exchanger. To obtain stringent level of silica mixed bed should be implemented.
Sanfoundry Global Education & Learning Series – Waste Water Engineering.
To practice all areas of Waste Water Engineering, here is complete set of 1000+ Multiple Choice Questions and Answers.
- Apply for Civil Engineering Internship
- Check Civil Engineering Books
- Check Waste Water Engineering Books
- Practice Civil Engineering MCQs