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Read the extract given below and answer any 5 out of 6 questions:
Every litre of waste water discharged by our industry pollutes eight times the quantity of fresh water. How can the industrial pollution of fresh water be reduced? Some suggestions are-
(i) Minimising the use of water for processing by reusing and recycling it in two or more successive stages.
(ii) Harvesting of rainwater to meet water requirements.
(iii) Treating hot water and effluents before releasing them in rivers and ponds. Treatment of industrial effluents can be done in three phases.
(a) Primary treatment by mechanical means involves screening, grinding, flocculation and sedimentation.
(b) Secondary treatment is by biological process.
(c) Tertiary treatment by biological, chemical and physical processes. This involves recycling of waste water.
Overdrawing of ground water reserves by industry where there is a threat to ground water resources also needs to be regulated legally. Particulate matter in the air can be reduced by fitting smoke stacks to factories with electrostatic precipitators, fabric filters, scrubbers and inertial separators. Smoke can be reduced by using oil or gas instead of coal in factories. Machinery and equipment can be used and generators should be fitted with silencers. Almost all machinery can be redesigned to increase energy efficiency and reduce noise. Noise absorbing material may be used apart from personal use of earplugs and earphones. The challenge of sustainable development requires integration of economic development with environmental concerns.
Question 2.1:
How many treatments are there for industrial effluents?
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Answer :
From the paragraph
Treatment of industrial effluents can be done in three phases .
(a) Primary treatment by mechanical means involves screening, grinding, flocculation and sedimentation.
(b) Secondary treatment is by biological process.
(c) Tertiary treatment by biological, chemical and physical processes. This involves recycling wastewater.
There are three types of treatment for industrial effluents, i.e. primary , secondary and tertiary .
Question 2.2:
What could be done to reduce pollution of machinery and equipment?
Answer:
From the paragraph
Almost all machinery can be redesigned to increase energy efficiency and reduce noise .
To reduce pollution of machinery and equipment, machinery can be redesigned to increase efficiency and reduce noise .
Question 2.3:
What are the challenges of sustainable development faced in India?
Answer:
From the paragraph
The challenge of sustainable development requires the integration of economic development with environmental concerns.
The challenges that sustainable development faces are that it requires the integration of economic development with environmental concerns.
Question 2.4:
Suggest any one way of reducing industrial pollution of fresh water.
Answer:
From the paragraph
(i) Minimising the use of water for processing by reusing and recycling it in two or more successive stages.
(ii) Harvesting of rainwater to meet water requirements .
(iii) Treating hot water and effluents before releasing them in rivers and ponds.
Some suggestions to reduce industrial pollution are
- By minimising the use of water for processing by reusing and recycling it in two or more successive stages.
- By using rainwater to meet the water requirement for harvest .
- By treating hot water and effluents (liquid waste) from industries before releasing them into rivers and ponds.
Question 2.5:
State any one use of treated waste water.
Answer
Treated wastewater can be used in irrigation , fire-fighting or to clean roads .
Question 2.6
How can particulate matter in the air be reduced?
Answer
From the paragraph
Particulate matter in the air can be reduced by fitting smoke stacks to factories with electrostatic precipitators, fabric filters, scrubbers and inertial separators.
To reduce particulate matter in the air we should fit smoke stacks to factories with electrostatic precipitators, fabric filters, scrubbers and inertial separators.
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