Absorbers will account for almost one half of the sales. These are used to capture odorous gases in municipal waste treatment plants, acid gases from incinerators, chemical and mining operations, as well as applications in pulp and paper, refining and many other industries. Absorbers used to capture power plant flue gases are not included in these totals but are in a separate report.
The second largest market is adsorption. This is primarily with activated carbon and includes both solvent recovery as well as odor control. Biofilters are used for odor control in municipal wastewater plants. Dry scrubbers are used to capture HCl and other acid gases emitted by municipal waste combustion. Venturi and other scrubber types are used to capture particulate in foundry sand systems, grain dryers and many other applications involving sticky dust.
Municipal wastewater and municipal waste combustion are the two biggest industry segments. There are a number of new incinerators being built in China and other Asian countries. Either dry or wet scrubbers are used with incinerators. The metals industry in developing countries favors scrubbers over baghouses. They are less costly and more rugged. However, the efficiencies are lower.
There are nearly 1000 scrubber system vendors around the world. This very fractured industry is divided both geographically and by industry. There are relatively few suppliers of nozzles, packing, and mist eliminators used in the systems. The typical scrubber system designer does not have his own manufacturing facility. He subcontracts the design with a metal fabricator.
The supply of activated carbon for the adsorption applications is a big market of over $0.5 billion/yr. This does not include the carbon used for mercury removal in power plants. This power market is likely to be bigger than the other applications combined.
Scrubber system suppliers typically supply the wastewater treatment systems needed to purify any liquid discharged. Most scrubbers operate with recycled scrubber liquor and a relatively small bleed to final treatment.