ESE Prelims 2022 Achievers Quiz 1 for ESE & GATE CE Exams

Question 1

The MLSS concentration in an serration tank is 2000 mg/l and the sludge volume after 30 minutes of setting in a 1000 ml graduated cylinder is 175 ml. The value of sludge density index (SDI) will be nearly

Question 2

Calculate the volume of anaerobic digestion take if the volume of raw sludge is 25 m³/d and the volume of digested sludge is 7 m³/d, mean cell residence time is 12 days :

Question 3

A sanitary landfill has an available space of 12.5 ha for the dumping of solid waste. On average, 640 m³ of solid waste is dumped at the site 5 days per week. This waste is compacted to twice its delivered density. If a landfill is to be designed for 10 years, the average depth of the landfill required is :

Question 4

Statement (I) : Anaerobic sludge digester, by itself, is considered to be the better method than other methods of sludge treatment.

Statement (II) : During Anaerobic sludge digestion, CH₄ is produced; also rodents and other pests are attracted when digester sludge is dried.

Question 5

Critical dissolved oxygen (D.O.) deficit occurs in which one of the following zones of pollution of ‘oxygen sag curve’ in case of self- purification of natural steam?

Question 6

Consider the following statements in respect of the troposphere:

1. The gaseous content constantly churns by turbulence and mixing.

2. Its behaviour makes the weather

3. The ultimate energy source for producing any weather change is the sun

4. The height of the troposphere is nearly 11 km at the equatorial belt and is 5 km at the poles.

Which of these are true of the troposphere?

Question 7

Consider the following statements regarding air pollution:
1) The pollutant caused by incomplete combustion of organic matter is carbon monoxide.
2) Depletion of ozone in outer atmosphere may trigger skin .
3) Acid rains are caused by SO₂ and NO_x.
4) The permissible standard for SO₂ in air for residential areas in India is

.
Which of the above statements are correct?

Question 8

Fanning type of plume behaviour takes place when

Question 9

Consider the following statements in respect of aerated grit chamber:
1) The grit accumulates at the bottom in advancing spiral-flow aeration tanks, location ally preceded by grit chambers, led to the eventual development of aerated grit chambers.
2. The excessive wear on grit handling equipment is a major factor for the popularity of aerated grit chambers.
3. Aerated grit chambers are designed to provide detention period of 1 minute at maximum rate of flow.
4. Diffusers are located at 0.45 m to 0.6 m above the bottom of the chamber.
Which of the above statements are correct?

Question 10

Which of the following statements regarding comparison of Septic tank and Imhoff tank is NOT correct.