Scrubbers are air pollution control devices that remove harmful pollutants from industrial exhaust gases before release. They are commonly used in power plants, chemical plants, and metal processing to reduce emissions like sulfur dioxide, nitrogen oxides, particulate matter, and volatile organic compounds. There are different types of scrubbers that use liquid or solid materials to absorb and capture pollutants via chemical reactions or physical trapping. Scrubbers help industries comply with regulations while improving workplace safety, reducing odors, and benefiting the long-term environment. Their performance is measured through solid waste characterization, operational parameters, and periodic testing.

1. Presented by: Supervisor:
Shayma Noraddin Dr. Najmaddin Nerway
Rand Hussein
Control of air pollution by
equipment (scrubbers)

2. Contents
◦ Introduction
◦ What are scrubbers
◦ Technologies for Air Pollution control
◦ Types of scrubbers
◦ Key pollutants removal
◦ Effects
◦ Measurements

3. Introduction
Scrubbers are air pollution control devices used to remove harmful pollutants from
industrial exhaust gases before they are released into the atmosphere. They are
commonly used in various industries, including power plants, chemical
manufacturing, and metal processing, to reduce the emission of pollutants such as
sulfur dioxide (SO2), nitrogen oxides (NOx), particulate matter (PM), and volatile
organic compounds (VOCs).

4. What are Scrubbers?
Scrubbers are used as depuration systems that specifically eliminate the emissions of acid
gases (SO2) produced in the combustion of pollutants. Wet scrubbers receive their name
from the fact that liquids are used as a scrubbing medium and the by-products of the
scrubbing system are liquid solution or slurry. Wet scrubbers can serve two simultaneous
functions: particulate collection and acid gas control. Gas emissions are absorbed in
devices columns that attempt to maximize liquid-to-gas contact to achieve maximum
absorption of the pollutants into the liquid phase.

5. Technologies for Air Pollution
control
When it comes to air pollution control, there are several technologies widely used
nowadays that can be installed at production plants to reduce exhaust air emissions
generated during industrial processes. Some of those technologies are: Regenerative
Thermal Oxidizers (also known as RTO), Direct Thermal Oxidizers, DeNOx systems,
Bagfilters, Biofilters, Scrubbers, etc.

6. Types of scrubber
• Spray towers
• Venturi scrubbers
• Cyclone scrubbers
• Packed scrubbers
• Mechanical scrubbers

7. Spray towers

8. Venturi scrubbers

9. Cyclone scrubbers

10. Packed scrubbers

11. Mechanical scrubbers

12. Key Pollutants Removal
 SO2 Removal: Wet scrubbers are particularly effective in removing sulfur dioxide
(SO2) by using an alkaline solution (e.g., limestone slurry) to react with and form
calcium sulfate or calcium sulfite, which can be disposed of safely.
 NOx Removal: Selective catalytic reduction (SCR) and selective non-catalytic reduction
(SNCR) are often used for nitrogen oxides (NOx) control, rather than scrubbers.
However, some wet scrubbers can also remove a portion of NOx through chemical
reactions.
 Particulate Matter Removal: Both wet and dry scrubbers can capture particulate
matter effectively by physically trapping it in the liquid or on the solid sorbents.
 VOC Removal: Wet scrubbers can also capture volatile organic compounds (VOCs) by
absorbing them into the liquid.

13. Effect
The use of air pollution control equipment such as scrubbers has several positive effects
on the environment, public health, and industrial operations. Here are some of the key
effects of using scrubbers for air pollution control:
1. Regulatory Compliance
2. Improved Workplace Safety
3. Reduced Odors
4. Long-term Environmental Benefits

14. 1.Regulatory Compliance: Scrubbers enable industries to comply with stringent environmental
regulations and emission standards set by government agencies. Compliance with these regulations
helps prevent legal penalties, fines, and sanctions.
2.Improved Workplace Safety: By reducing the release of hazardous substances, scrubbers also
contribute to safer working conditions for employees in industrial facilities.
3.Reduced Odors: In addition to capturing pollutants, scrubbers can also help control odors associated
with industrial processes, contributing to better quality of life for nearby residents.
4.Long-term Environmental Benefits: Effective air pollution control with scrubbers contributes to
the long-term sustainability of the environment. It helps mitigate the negative impacts of industrial
activities on air quality, ecosystems, and public health.

15. Measurements
The effectiveness of air pollution control equipment like scrubbers is typically
measured through various methods and parameters to ensure that emissions from
industrial processes meet regulatory standards. Here are some common
measurements and methods used to assess the performance of scrubbers in
controlling air pollution:

16. 1.Solid Waste Characterization:
• For dry scrubbers or any scrubbing system that generates solid waste, it's important to measure and
characterize the waste to ensure proper disposal. This includes measuring the quantity and chemical
composition of the captured solids.
2.Operational Parameters:
• Monitoring and recording operational parameters, such as fan speed, pump operation, and valve settings,
are critical to maintaining the scrubber's optimal performance.
3.Periodic Testing:
• Regulatory agencies may require periodic testing and inspection of scrubbers to ensure compliance with
emissions standards. This can include performance testing conducted by third-party organizations.