An Introduction To Different Types Of Fume Scrubbers

By Author: Scott Lintern
Total Articles: 916
Comment this article

Industries produce odors, acid, chemical, and NOx fumes. Controlling these types of health hazard elements is so important for preventing environmental releases, ensuring regulatory compliance, and protecting employees' safety and health. Proper fume capture, control and scrubbing exhaust systems help companies to avoid these types of problems. A good scrubber must maximize the gas liquid contact area while minimizing the pressure drop through the scrubber.

The selection of the scrubbers depends on the type of application, level or efficiency of filtration and type of gas to be cleaned. Scrubbers are available in a number of different types, such as---

Impingement plate scrubbers
Packed bed scrubbers
Venturi scrubbers
Counter Flow fume scrubbers

Impingement Plate Scrubbers

If there is dust within the stream impingement plate scrubbers are recommended. In these scrubbers gas passes up through the openings in the perforated plates. In the design, an impingement baffle is used above each individual hole. These wetted baffles create tiny droplets that are the heart of the collection ...
... process. The benefit of these scrubbers is their high absorption efficiency, up to 98-99%, for gases and vapors by using sufficient number of plates.

Packed Bed Scrubbers

To remove gaseous or vaporous pollutants from an air stream packed bed scrubbers are used. In this process contaminated air stream is contacted with scrubbing liquor. This liquor absorbs or chemically reacts with the pollutants. Then the clean air is discharged to the atmosphere. The liquor that contains the chemicals is recycled and reused or disposed of in an approved manner.

Packed Bed Scrubbers are available in the following three designs---

Vertical Packed Tower Fume Scrubber
Horizontal Packed Bed Fume Scrubber
Chromic Acid Scrubber

Vertical Packed Tower Fume Scrubber is a counter-current unit custom designed to meet or exceed the specific removal efficiency required. Non-metallic construction is used for many installations, but special construction materials including stainless steel or FRP lined mild steel are available to meet specific applications. Some Vertical Packed Tower Fume Scrubbers are often included in complete pollution control systems to meet the demands of more complex processes for difficult to remove fumes.

Horizontal Packed Bed Fume Scrubbers are high efficiency, low maintenance scrubbers. It is used to remove water soluble contaminants by means of gas absorption or mechanical impingement. These units can be built in either horizontal or vertical designs, depending on space limitations or layout preference.

Hexavalent chrome mist which is emissioned from chrome plating and chromic acid anodizing operations can't be removed effectively by conventional packed tower scrubber. Chromic Acid Scrubber is a modified type of horizontal scrubbing unit using specialized mesh filter pads with periodic flushing that is required to meet regulatory guidelines for this contaminant.

Venturi Scrubbers

To remove fine particles from volatile, hazardous or corrosive gas streams, or to handle gas streams containing solid materials Venturi scrubbers are often installed. It is mainly used for applications with high dust loadings. Collection efficiency for venturi scrubbers is 95-98.5% that depends on the stages they have, three, four or five.

Counter Flow Fume Scrubbers

For contaminants that are difficult to absorb for all airflow requirements counter flow fume scrubbers are designed. The advantage that it offers is in the efficient and effective use of scrubbing solutions. Fro high removal efficiency, mist and separating solutions carry-over at high gas velocity is minimized by the use of dry packed bed mist eliminators. To achieve a maximum in efficiency at a minimum of cost counter flow separators are available with a variety of tower internals.

According to the today's industrial laws employee friendly industrial environment is a must. The use of a Fume Scrubber is an easy solution to the problem. To install a fume scrubber it is advisable to take the help of an expert as proper fume control equipment requires the proper installation and system integration to be the most effective.

About Author:

Scott Lintern from Western Air Ducts writes about Fume Scrubber. For more information on Fume Scrubber please visit www.wad.co.uk