Scrubbers Technology For Air Pollution Control

Air Pollution Control by Scrubbers

Air pollution control

Air pollution poses a significant threat to both human health and the environment. Among the various sources of air pollutants, industries, and power plants are major contributors. To mitigate the adverse effects of industrial emissions, various technologies have been developed, and one such crucial tool in the fight against air pollution is the scrubber.

What Do Scrubbers Do?

Pollutants from industrial exhaust streams are removed using scrubbers, also known as air scrubbers, before they are released into the atmosphere. These gadgets are essential for cutting back on the release of dangerous gases such as sulfur dioxide (SO2), nitrogen oxides (NOx), particulate matter, and volatile organic compounds (VOCs).

WHAT ARE INDUSTRIAL SCRUBBERS?

Industrial scrubbers are pollution filtration systems that utilize solids (in “dry scrubbers”), or water or other liquids (in “wet scrubbers”) to remove gas pollutants and odors from exhaust streams. Scrubbers are the most appropriate solution to eliminate particulate matter and acid gases from exhaust streams.

TYPES OF INDUSTRIAL SCRUBBERS

There are two main types of industrial scrubbers

1. Wet scrubbers

2. Dry scrubbers

Wet Scrubbers:

These are the most common types of scrubbers and use water or other liquid solutions to capture and remove pollutants. Venture scrubbers, packed bed scrubbers, and spray tower scrubbers are examples of wet scrubbers.

Operating principle

In its most basic form, water is encapsulated in a metal or composite container. Contaminated gas is passed through the water, and the water absorbs the contaminants. Other liquids can be used to effectively remove varied contaminates. These liquids differ in the chemical composition and the overall charge. These liquids can be anything from highly positively or negatively charged to non-charged. Because pollutants can differ in their charge, scrubbers can be packed with a liquid that will bind most effectively to remove the ‘contaminate’ from the gas. Several configurations of wet scrubbers are in use. In a spray-tower scrubber, an upward-flowing airstream is washed by water sprayed downward from a series of nozzles. The water is recirculated after it is sufficiently cleaned to prevent clogging of the nozzles. Spray-tower scrubbers can remove 90 percent of particulates larger than about 8 μm. The gas exiting the wet scrubber is thus cleaner.

2-Dry scrubbers

Unlike wet industrial scrubbers, dry scrubbers do not utilize a liquid to absorb contaminants. Because of this difference, steam is not produced by the reaction, and a wastewater system is not needed. This is one of the most common pieces of equipment found in manufacturing plants, because of its ability to handle high-temperature, highly acidic exhaust streams.

 Operating principle.

A dry scrubber works by combining carefully chosen chemical reagents with the exhaust stream at incredibly high speeds that react with or absorb the compounds in the stream. These chemicals react differently, depending on which compounds are being targeted; reactions either neutralize the dangerous VOCs or absorb them into a different compound altogether. Once converted, the substance left over can then be disposed of or transported easily. Each type of scrubber media removes particles and compounds in a different way; some chemical reactions, while others use electrostatic adhesion.

WHAT SCRUBBERS TREAT?

Dry and wet scrubbers are used to treat or clean the following lists of chemicals from a process exhaust air stream.

• Ammonia
• Chlorine
• Hydrochloric Acid
• Chlorinated Silences
• Metallic Compounds
• Sulfur Dioxide
• Hydrogen Sulfide
• Boron Trifluoride
• Amines

ADVANTAGES AND DISADVANTAGES OF SCRUBBERS

Advantages

• Can handle flammable and explosive dusts with little risk
  • Provides gas absorption and dust collection in a single unit
  • Provides cooling of hot gases
  • Compact; can often be retrofitted into existing collection systems
  • Corrosive gases and dust can be neutralized

Disadvantages

• High potential for corrosion problems
• Collected particulate may be contaminated and unrecyclable
• Protection against freezing is required. Certain streams may require reheating to avoid visible plumes
• Disposal of waste sludge can be very expensive
• Requires makeup water to replace purged liquid and disposed sludge

COMMONLY USED

Scrubbers are commonly used in these industries

1. Asphalt processing

2. Pharmaceuticals

3. Textile Processing

4. Vinyl Manufacturing

5. Oil and Gas

6. Acid mist control

7. Fertilizer Manufacturing

8. Steel Processing

9. Cocoa Processing

10. Nuclear Waste filtration

CONCLUSION

In conclusion, scrubbers are vital components of air pollution control systems, playing a crucial role in reducing the impact of industrial emissions on our environment and health. As technology advances, the development of more efficient and sustainable scrubbing techniques will further contribute to creating a cleaner and healthier atmosphere for

Also read: PLASTIC WASTE MANAGEMENT