摘要:
Flue gas processing is described. A circulating dry flue gas desulfurization (DFGD) scrubber is positioned upstream of a wet flue gas desulfurization (WFGD) scrubber. Flue gas temperature and humidity is controlled. Reagent use is monitored and controlled. The DFGD scrubber is controlled without concern for sulfur dioxide absorption and thus reagent utilization is controlled based on the goal of removing one or more of: sulfur trioxide and/or other acid gases. In some embodiments the circulating DFGD scrubber removes the majority of sulfur trioxide, HCL, and/or HF from the flue gas stream supplied to the DFGD scrubber. The DFGD scrubber is followed by the WFGD scrubber that removes sulfur dioxide and mercury, to achieve a high degree of pollutant removal at a low operating cost as compared to some other systems. WFGD scrubber liquid waste is sent to the circulating DFGD scrubber and used for temperature and/or humidity control purposes.
摘要:
A method of making a sorbent of an activated carbon substrate having a metal sulfide, which may be useful, for example, for removing a contaminant from a fluid stream.
摘要:
An absorbing tower is provided in its side wall with a gas entrance for introducing a combustion exhaust gas into the absorbing tower, and an absorbing liquid is sprayed from the nozzles of a spray header into the exhaust gas introduced to rise from the gas entrance. A trough is arranged in the side wall of the absorbing tower and above the gas entrance, and a nose having a horseshoe shape in a top plan view and extending into tower is disposed in the tower side wall portion of the gas entrance other than the portion arranging the trough and at the same or at substantially the same height as the portion of the trough. The absorbing liquid, which is sprayed from the nozzle and drops along the absorbing tower wall portion, is rescattered to the center portion of the absorbing tower excepting the entrance of the absorbing tower, so that the gas-liquid contact efficiency is improved while suppressing an increase in pressure loss, thereby to prevent the drift of the gas at the tower wall portion.
摘要:
The invention concerns a capture tank for capturing a captive target compound from a gaseous and/or vaporous mixture comprising at least the captive target compound and one other material, or for capturing, concentrating or crystallising a target compound from a liquid mixture or solution comprising the target compound and at least one other material, the capture tank comprising an enclosure having a top region, a bottom region and at least one side defining the enclosure, the enclosure being at least partly open in its top region in order to communicate in use of the capture tank with the gaseous and/or vaporous mixture and for permitting ingress of a gaseous and/or vaporous mixture into the enclosure; the enclosure communicating in its bottom region with a reservoir for receiving the captured captive target compound; having means associated with its at least one side and/or its bottom region for permitting egress from the enclosure of the gaseous and/or vaporous mixture in at least partially captive target compound-depleted form; and having means for sparging at least partially through the enclosure from top to bottom a liquid mixture or solution for entraining the gaseous and/or vaporous mixture in the enclosure and carrying the entrained gaseous and/or vaporous mixture towards the bottom region of the enclosure, and a process for its operation.
摘要:
A method and apparatus for treating an exhaust gas comprising heavy metals, wherein the apparatus comprises a heat recovery unit, recovering exhaust gas heat at an exit of the air preheater; a precipitator, collecting soot/dust contained in an exhaust gas at an exit of the heat recovery unit; a wet flue gas desulfurizer, removing sulfur oxides contained in the exhaust gas at the exit of the precipitator; and a reheater, heating the exhaust gas at the exit of the wet flue gas desulfurizer. Each of the heat recovery unit and the reheater has a heat exchanger tube, and a circulation line is disposed to connect the heat exchanger tubes. A sulfur trioxide (SO3) removing agent is supplied to the upstream side of the heat recovery unit, and the temperature of the exhaust gas at the exit of the heat recovery unit is adjusted to not more than a dew point of sulfur trioxide.
摘要:
A flue gas desulfurization process and system that utilize ammonia as a reactant, and in which any hydrogen sulfide and/or mercaptans within the ammonia are separated during the desulfurization process so as to prevent their release into the atmosphere. The process and system entail absorbing acidic gases from a flue gas with a scrubbing media containing ammonium sulfate to produce a stream of scrubbed flue gas, collecting the scrubbing media containing the absorbed acidic gases, injecting into the collected scrubbing media a source of ammonia that is laden with hydrogen sulfide and/or mercaptans so that the injected ammonia is absorbed into and reacted with the collected scrubbing media, stripping the hydrogen sulfide and/or mercaptans from the collected scrubbing media by causing the hydrogen sulfide and/or mercaptans to exit the collected scrubbing media as stripped gases, and collecting the stripped gases without allowing the stripped gases to enter the stream of scrubbed flue gas.
摘要:
Methods and apparatus for pollution control which are well suited for use in a coal power plant are described. Ash is collected and injected into the flue gas stream at a location upstream of a cooling module. The ash acts as an absorbent and/or reactant material onto which condensate may condense. By re-introducing ash to keep the condensation forming wet areas within the system, lower cost materials which are less corrosion resistant than needed for wet operating conditions can be used. Mercury recovery and SO3 removal is facilitated by the cooling process and re-introduction of collected ash. Activated carbon and/or an alkali absorbent material may be added. Use of a dry ESP and/or fabric filter as opposed to a wet ESP for particulate collection leads to cost benefits. Energy recovered by the cooling of the flue gas may be re-used to heat turbine condensate leading to improved energy efficiency.
摘要:
A flue gas desulfurization process and system that utilize ammonia as a reactant, and in which any hydrogen sulfide and/or mercaptans within the ammonia are separated during the desulfurization process so as to prevent their release into the atmosphere. The process and system entail absorbing acidic gases from a flue gas with a scrubbing media containing ammonium sulfate to produce a stream of scrubbed flue gas, collecting the scrubbing media containing the absorbed acidic gases, injecting into the collected scrubbing media a source of ammonia that is laden with hydrogen sulfide and/or mercaptans so that the injected ammonia is absorbed into and reacted with the collected scrubbing media, stripping the hydrogen sulfide and/or mercaptans from the collected scrubbing media by causing the hydrogen sulfide and/or mercaptans to exit the collected scrubbing media as stripped gases, and collecting the stripped gases without allowing the stripped gases to enter the stream of scrubbed flue gas.
摘要:
A canister including an elongated hollow plastic body having a wall with inner and outer surfaces, an edge portion on the wall defining an open end, an end on the edge portion extending transversely to the inner and outer surfaces, a porous plastic member having an outer edge portion extending across the open end and fused to the end, an inner portion on the porous plastic member located radially inwardly of the outer edge portion and extending into the body and fused to the inner surface of the wall adjacent the end thereof, and a gas-treating material in the body. A method of fabricating the above canister including the steps of applying pressure and vibratory welding energy to the porous member to thereby cause the member which was originally planar in shape to have its outer edge compressed against the end of the body and fused thereto and the central portion inwardly of the outer edge forced into the body and its outer edge fused to the inner surface of the body adjacent the end.
摘要:
A method for reducing pollution emissions from a glass melting furnace using electrostatic granular bed (EGB) technology. The granules in the EGB filter are themselves formed from an alkaline earth metal material. The granules react with sulfur compounds in the exhaust gas and form a layer of alkaline earth metal sulfates and sulfites in the granules. Simultaneously alkali metal-containing particles are deposited on the granules. The accumulated layers of pollutants are easily removed by mechanical agitation.