The Taj Mahal has faced damage because of acid rain. Sulphuric dioxide when mixed with moisture causes corrosion of metals such as steel, copper, and zinc. Water pollution may severely affect human, plant, and animal life. Soil pollution affects humans and animals through the process of the food chain. Radiations are extremely dangerous for human health as they produce harmful changes in the body cells and affect genes. So the question is, ‘How to Control Pollution?’.
How to Control Air Pollution?
Two methods are considered the most effective for dealing with the problem of air pollution. These are
Source Correction Methods
It is important to reduce air pollution from the source itself. In industries, this can be achieved by designing and developing schemes and processes which can minimize air pollution in the early stages.
Pollution Control Equipment
Air pollution not only contains gaseous matter but also solid particles. Many devices and equipment have been designed to prevent air pollution. While choosing a device, any industry should keep the following points in mind:
- Amount of volume of particulate matter which has to be handled.
- Chemical and physical characteristics of the particulate along with its size.
- Temperature and humidity of gaseous medium.
- Concentration of gases in particulate size.
- Pollution control devices are basically classified into two categories—devices which control particulate contamination and devices which control gaseous contamination.
How to Control Water Pollution?
Sources of water pollution which cause an inflow of pollutants over a large area are known as non-point sources. Example: Runoff from agricultural fields. The following steps should be taken to control water pollution from non-point sources:
- Two separate drainages should be built for sewage and rainwater so that both rainwater and sewage do not overflow together.
- Nitrogen-fixing plants should be planted to reduce the use of chemical fertilisers.
- Agrochemicals and pesticides should be used judiciously to prevent them from draining into a water body.
- Efforts should be made to prevent runoff of manures.
- Biofertilisers and biopesticides should be used.
Sources that discharge pollutants to only one specific site are known as point sources. Example: Discharge of effluents from the factory into a river. To prevent pollution from point sources, it is essential to first treat wastewater before it is discharged. Laws should be made carrying strict punishment for discharging untreated wastewater into any water body.
Treatment of Plants
Wastewater should undergo three types of treatments to purify it. These are
- In primary treatment of water, screens, grit chambers and sedimentation tanks are arranged in a serial order.
- Water which passes through them is treated with chlorine gas which kills the harmful bacteria in water. However, dissolved organic matter like salts cannot be treated in this method.
- In this method, the organic matter which is present in water is biologically degraded by microorganisms. When water enters a tank, it comes into contact with microorganisms.
- Air is introduced into the tank through diffusers. Microorganisms in the presence of oxygen break the organic matter and the impurities then settle to the bottom of the tank which are later removed.
- Water is then treated with chlorine gas which then kills the rest of the harmful organisms.
In this method, nutrients such as nitrogen or phosphorus are removed. This water can be reused for industrial, agricultural, and domestic purposes.
How to Control Soil Pollution?
In open dumping, wastes are dumped in open spaces located far away from the limits of the city. This kind of waste disposal is not safe and has many limitations. The dumping of different types of wastes makes such dumping grounds as the breeding ground of mosquitoes and flies. The burning of these wastes also pollutes the air. The situation can become worse during rains. Rainwater may carry these wastes to nearby lakes, rivers, or ponds and pollutes them.
Wastes are disposed of away from the city in sanitary landfills. The waste is first spread in layers and then is compacted tightly so that its volume is reduced. The waste is then covered by soil and subjected to bacterial decomposition. Sanitary landfills are useful as the wastes are not attacked by rodents or insects. One precaution which needs to be taken is that landfills should not be located in areas that have high underground water levels as they may get polluted.
In the composting method, household and municipal wastes are decomposed by the aerobic method. The wastes are decomposed by microorganisms. This is a useful method of waste decomposition as wastes are decomposed by microorganisms into humus which adds to the fertility of the soil.
During incineration, municipal wastes are burned at a very high temperature. Many materials like metal do not get burnt. These are then recycled. This method however pollutes the air with fly ash and sulphur dioxide. It is also an expensive process as proper devices for controlling air pollution need to be installed.
This is a method in which wastes are segregated. Clothes, paper, glass, and metals are stored in different bins. Apart from these methods, effluents should be properly treated before they are discharged into the soil. Biofertilizers and manures should be used instead of chemical fertilizers.
How to Control Radioactive Pollution?
Radioactive waste is the most dangerous pollutant on the Earth as it is not easy to safely dispose of. These wastes remain in the environment for a long period. Any leakage in a nuclear plant may threaten the survival of humans living in nearby areas. It also has disastrous effects on plants, animals, and soil.
- The use of X-rays should be minimized.
- Atomic or nuclear reactors should be regularly checked to ensure safety conditions.
- Nuclear devices should be tested deep underground.
- Production of radioisotopes should be minimized.
- In nuclear mines, wet drilling should be used along with underground drainage.
- Nuclear wastes should be handled with care and should be stored in shielded and corrosion-proof containers and then stored deep underground so that they may not escape and their proper decay takes place.
- Radiation levels should always be kept within permissible limits.
- Radiation-resistant walls should be built around areas located close to nuclear reactors.
- Ground disposal of radiation wastes should be under approved rock and soil
Also, Read Bhopal Gas Tragedy Causes and Consequences