A contaminated gas stream can be passed through an in-line mixing device, positioned in a duct containing the contaminated gas stream, to form a turbulent contaminated gas stream. One or more of the following is true: (a) a width of the in-line mixing device is no more than about 75% of a width of the duct at the position of the in-line mixing device; (b) a height of the in-line mixing device is no more than about 75% of a height of the duct at the position of the in-line mixing device; and (c) a cross-sectional area of the mixing device normal to a direction of gas flow is no more than about 75% of a cross-sectional area of the duct at the position of the in-line mixing device. An additive can be introduced into the contaminated gas stream to cause the removal of the contaminant by a particulate control device.

The present invention relates to an advanced system for the removal of air pollutants from combustion and non-combustion processes that generate air pollutants that are regulated by environmental agencies. The pollutants include, but are not limited to, particulate matter; acid gases including sulphur dioxide, hydrogen chloride and hydrogen fluoride; metals such as mercury, dioxins, VOCs and reagents such as ammonia. The system collects and processes the polluted gas stream through two forms of wet method scrubbing technology. The gas is first passed through a wet scrubbing reactor capable of complete interaction between the gas and the selected liquid scrubbing reagent at one or more interfaces. The scrubbing medium is selected for its reactivity with the pollutants targeted in the process, its cost and impact on the environment. From the exit of the scrubbing reactor the gas is directed through a wet electrostatic precipitator to remove the remaining targeted pollutants to very high removal efficiency.

Several embodiments of the present technology are directed to the removal of one or more air pollutants using cooling and/or calcium-containing particles. In some embodiments, a method for removing air pollutants comprises flowing a gas stream having calcium-containing particles and one or more of mercury or hydrochloric acid molecules, and cooling the gas stream, thereby causing at least a portion of the calcium-containing particles to adsorb to the mercury and/or hydrochloric acid molecules in the gas stream. The method can further comprise, after cooling the gas stream, filtering the gas stream to remove at least a portion of the calcium-containing particles having adsorbed mercury and hydrochloric acid.

The flue gas treatment system (1) comprises a reactor (2), a pre-separator (3) downstream of the reactor (2), a separator (4) such as a fabric filter downstream of the pre-separator (3), a humidifier (5) downstream of the separator (4), a supply (7) of a pure fresh reagent into the flue gas (FG) downstream of the pre-separator (3) and upstream of or at the separator (4).

The present invention relates generally to the field of emission control equipment for boilers, heaters, kilns, or other flue gas-, or combustion gas-, generating devices (e.g., those located at power plants, processing plants, etc.) and, in particular to a new and useful method and apparatus for: (a) achieving a reduction in the level of one or more halogens, or halogen-containing compounds, necessary to affect gas-phase mercury control; (b) permitting the oxidation of at least a portion of any elemental mercury (Hg.sup.0) contained in a flue gas and/or combustion gas stream; and/or (c) permitting the oxidation of at least a portion of any elemental mercury (Hg.sup.0) contained in a flue gas and/or combustion gas stream so that the use of at least one post-oxidation mercury capture method and/or process results in the capture of at least a portion of oxidized mercury contained in the flue gas and/or combustion gas stream.

Several embodiments of the present technology are directed to the removal of one or more air pollutants using cooling and/or calcium-containing particles. In some embodiments, a method for removing air pollutants comprises flowing a gas stream having calcium-containing particles and one or more of mercury or hydrochloric acid molecules, and cooling the gas stream, thereby causing at least a portion of the calcium-containing particles to adsorb to the mercury and/or hydrochloric acid molecules in the gas stream. The method can further comprise, after cooling the gas stream, filtering the gas stream to remove at least a portion of the calcium-containing particles having adsorbed mercury and hydrochloric acid.

The description relates to reducing hydrochloric acid in cement kilns. In one aspect, an aqueous copper-based chloride remediator is introduced into contact with combustion gases from a cement kiln. Injection is made into a defined introduction zone under conditions effective for HCl emissions control wherein the temperature is within the range of from 300 F. to 800 F., preferably from 550 F. to 750 F. The resulting gases are discharged from the defined zone following sufficient reaction time to reduce the HCl concentration in the gases.

A dry scrubbing system and process wherein an acid gas comprising at least one pollutant is modified in a humid zone of a duct such that a relative humidity of between 2% and 90% is achieved. The humidified gas is then contacted with chalked lime in a reaction zone. The reaction zone components are subsequently filtered in a filtering zone to provide a filtered gas having reduced concentration of the at least one pollutant when compared to the initial acid gas.

Provided is a catalyst system capable of removing perfluorinated compounds and nitrous oxide. An exhaust gas is heated in two stages through a heat exchange unit and applied to a heater unit. The heater unit generates a flame to heat the exhaust gas to a high temperature. A catalyst unit is directly connected to a heating space of the heater unit so the heated exhaust gas comes into contact with a catalyst, and the perfluorinated compounds and the nitrous oxide are decomposed in the catalyst unit.

Several embodiments of the present technology are directed to the removal of one or more air pollutants using cooling and/or calcium-containing particles. In some embodiments, a method for removing air pollutants comprises flowing a gas stream having calcium-containing particles and one or more of mercury or hydrochloric acid molecules, and cooling the gas stream, thereby causing at least a portion of the calcium-containing particles to adsorb to the mercury and/or hydrochloric acid molecules in the gas stream. The method can further comprise, after cooling the gas stream, filtering the gas stream to remove at least a portion of the calcium-containing particles having adsorbed mercury and hydrochloric acid.