The invention discloses methods and apparatus(es) for the removal and control of pollutants such as gases and suspended particulates in the air of an enclosed space or an outdoor environment by passing the air through absorbent media. The absorbent media includes any liquid, solid or combination of liquid and solid media that is capable of absorbing a material in which it comes in contact. In one aspect of the invention, formaldehyde is removed by air sparging through a liquid such as water, optionally containing additional scavenging agents.

Apparatus for removing ammonia from a gas stream includes primary and secondary scrubbers each of which includes a gas inlet, a gas outlet, and a slurry atomizer. The gas inlet of the primary scrubber is operatively connected to a gas stream having ammonia contained therein. A primary slurry feed system operatively connected to the slurry atomizer of the primary scrubber feeds to the slurry atomizer a primary slurry composition of a molybdic acid at a pH level. The gas inlet of the secondary scrubber is operatively connected to the gas outlet of the primary scrubber. A secondary slurry feed system operatively connected to a slurry atomizer of the secondary scrubber feeds to the slurry atomizer a secondary slurry composition of a molybdic acid at pH level. The pH level of the secondary slurry composition is lower than the pH level of the primary slurry composition.

A method for the reduction and prevention of mercury emissions into the environment from combusted fossil fuels or other off-gases with the use of hypobromite is disclosed. The hypobromite is used for the capture of mercury from the resulting flue gases using a flue gas desulfurization system or scrubber. The method uses hypobromite in conjunction with a scrubber to capture mercury and lower its emission and/or re-emission with stack gases. The method allows the use of coal as a cleaner and environmentally friendlier fuel source as well as capturing mercury from other processing systems.

The present invention relates in general to a process for removing mercury from a mercury-containing flue gas using dregs from a Kraft pulp mill green liquor clarifier. The dregs are washed with water to produce a particulate carbon slurry which is activated with hydrobromic acid and injected into a mercury-containing flue gas to oxidize and adsorb the mercury at temperatures less than about 900 F. A slurry of sodium hydroxide and calcium carbonate, optionally also obtained from Kraft mill waste, is injected into the hot flue gas to absorb and remove CO.sub.2, SO.sub.2, and SO.sub.3.

Processes and systems for treating Kraft pulping foul condensate are provided. The processes comprise removing volatile compounds from the foul condensate to produce a resulting condensate and removing methanol from the resulting condensate. The systems comprise a volatile compound removal stage and a methanol removal stage downstream of and in fluid communication with the volatile removal stage.