The invention relates to a method for increasing the absorbency of a material containing alkaline-earth carbonate and alkaline-earth hydroxide with regard to sulfur oxides and/or other pollutants, in particular in flue gas, wherein the material containing alkaline-earth carbonate and alkaline-earth hydroxide is activated by heating said material to approximately 250 C. to approximately 750 C. for a time period of 1 minute to 12 hours.

A treatment method for coal fly ash, and in particular sodic fly ash, comprises 1) contacting the coal fly ash with anhydrite, and 2) contacting the coal fly ash in the presence of water with at least one additive. The material obtained from the contacting steps (1) and (2) may be dried. The steps (1) and (2) may be carried simultaneously or sequentially. The additive may comprise at least one component selected from the group consisting of strontium-containing compounds, barium-containing compounds, dolomite, a dolomite derivative such as calcined or hydrated dolomite, water-soluble sources of silicate such as sodium or potassium silicate, iron-containing compounds, and any combinations thereof. A particularly preferred additive comprises sodium silicate. The method may be effective in reducing the sodium content in the fly ash (Na.sub.2O), reducing the alkalinity of the fly ash, and/or stabilizing at least one heavy metal such as selenium and/or arsenic to reduce their leachability.

A portable dry scrubber comprises a gas flow control module comprising a gas receiving unit that receives inflow of gas from surrounding atmosphere or from a gas source, a gas processing module that removes hazardous matter from the gas flowed in through the gas receiving unit and a connection module that connects the gas flow control module detachably to the gas processing module. The connection module comprises quick coupling device that establishes and disassembles a gas flow passage between the gas flow control module and the gas processing module. Example of the quick coupling device is a quick release vacuum flange that engages with a connecting flange of the gas flow control module.

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.

A treatment method for stabilizing a sodic fly ash to reduce their leachability which is provided by a combustion process when a sodium-based sorbent comes in contact with a flue gas generated by combustion to remove at least a portion of pollutants contained in the flue gas. The treatment method comprises contacting the sodic fly ash with at least one additive comprising calcium. The material obtained from the contacting step is preferably dried. The material may be selected from the group consisting of lime kiln, dust, fine limestone, quicklime, hydrated lime, dolomitic lime, dolomite, selectively calcined dolomite, hydrated dolomite, and any mixture of two or more thereof. A particularly preferred additive comprises lime kiln dust.

The present invention relates to a system for separating and recycling a perfluorinated or perfluor compound, and more particularly, to a system for separating and recycling a perfluorinated compound, which is developed to prevent damage of separation membranes and degradation of the separation efficiency of through the application of a constant pressure to respective separation membranes when the perfluoro compound passes through a plurality of separation membranes in a process of effectively separating, removing and recycling the perfluoro compound including sulfur hexafluoride primarily generated in a semiconductor manufacturing process.

An absorption column 1 for separating CO.sub.2 and a second acid gas from a gas stream, the column comprising a first and second section (4, 5) for the absorption of CO.sub.2 and the second acid gas; a solvent inlet in the second section for the addition of liquid stream 3 including an absorbent liquid for CO.sub.2 and the second acid gas; a gas inlet (21) in the first section for the addition of a gas stream (2) containing CO.sub.2 and the second acid gas; a gas outlet (15) in the second section of the column; a first solvent outlet (22) for the removal of at least a portion of the solvent (6) from the second section of the column and a second solvent outlet (23) for solvent stream (11) from the first section of the column; and a liquid flow distributor arrangement (8) to allow a portion of the solvent to flow from the second section of the column to the first section. A method of operating the apparatus and method of solvent extraction is also disclosed.

A method for treating a gas is shown which includes the steps of: injecting a powdered compound into the gas line, injecting an aqueous phase in droplet form into the line, capturing pollutants from the gases, and recovering the powdered compound separately. The step for injecting an aqueous phase in droplet form is done so as to moisten those particles of powdered compound in the gas line, when they are injected.

A system for recycling cooling devices, comprising a system part for catalytically oxidizing the pure hydrocarbon compounds and chlorofluorocarbons which accumulate during the recycling of the cooling devices. According to the invention, this system part comprises two reactors, provided mutually separated in the flow direction of the gases to be treated, a first reactor being used for catalytically oxidizing the pure hydrocarbon compounds while a second reactor is used for catalytically oxidizing chlorofluorocarbons.

A system for regulating an amount of fresh lime slurry introduced to a spray dry absorber. The control system includes a controller configured to receive input from a continuous emissions monitoring system (CEMS), a valve in communication with the controller and a spray dry absorber suction pump, the valve adapted to regulate an amount of fresh lime slurry provided to the spray dry absorber suction pump and a valve in communication with the controller and a pre-mix tank, the valve adapted to regulate an amount of fresh lime slurry provided to the pre-mix tank.