How Wet Gas Scrubbers Work
There are many types and models of wet gas scrubbers or acid gas absorbers in the marketplace. However, nearly all wet gas scrubbers work as follows:
- In most cases, flue gas from the customer’s process is not saturated. However, before acid gases such as SO2 can be removed, the gas stream must be adiabatically saturated or "quenched".
- Most scrubbers will have a section where liquid (typically water or the scrubbing reagent itself) is contacted with the incoming flue gas to adiabatically saturate, or "quench," the gas stream.
- Only after the gas has been quenched can acid gas and SO2 removal occur. This is accomplished in two steps:
- The acid gases are absorbed into the scrubbing liquid.
- Once absorbed, the acid gases react with the reagent, forming reaction by-products, which then must be removed from the clean gas.
- All scrubbers must have a method for removing the water droplets and reaction by-products from the gas before they exit the scrubber.
In addition to acid gas removal, customers often need removal of particulates as well. Most wet gas scrubbers will remove some particulate. However, another piece of equipment, such as a venturi scrubber, is often required to accomplish significant removal of particulate.