摘要:
A reagent injection system for reducing emissions from an engine includes a reagent container. A heating element is positioned in a heat transfer relationship with reagent stored within the container. An interchange tube includes a first end in receipt of a recirculated liquid reagent and a second open end positioned in the container. The interchange tube includes a bleed-off tube branching off of the interchange tube between the first and second ends. A terminal end of the bleed-off tube is positioned within a vapor dome above a surface of the reagent.
摘要:
An apparatus and method for mixing gas streams of different temperatures and/or compositions contemplates that at least one of the streams contains particle. The apparatus includes a main duct for the first gas stream and a plurality of duct assemblies extending in the main duct generally transversely to the first gas stream. Each assembly has plural inlets and outlets for receiving and discharging separate parts of the second gas stream, moving initially generally transverse to the first stream. The assemblies each have plural secondary ducts of mutually different lengths from inlet to outlet, the outlets being spaced from each other across the main duct for distributing the parts of the second gas stream into the first gas stream. A gas flow deflector is connected to each duct assembly for temporarily deflecting the first gas stream before it is combined with the parts of the second gas stream.
摘要:
An exhaust gas treating apparatus removes nitrogen oxides and mercury in exhaust gas from a boiler using an ammonia denitration catalyst, including: an ammonium chloride powder feed unit for feeding ammonium chloride, in powder form, into a vicinity of an entrance of an economizer provided to a combustion gas flue of the boiler and/or an economizer bypass unit, the fed ammonium chloride in powder form being sublimed by a combustion gas, to thereby feed hydrogen chloride and ammonia into the flue; and an ammonium chloride liquid feed unit for feeding ammonium chloride, in liquid form, into a vicinity of the entrance of the economizer and/or the economizer bypass unit, the ammonium chloride liquid feed unit also being capable of feeding ammonium chloride, vaporization of the fed ammonium chloride in liquid form by the combustion gas also allowing hydrogen chloride and ammonia to be fed into the flue.
摘要:
A flue gas control system of a coal combustion boiler according to the present invention includes: an HCI atomizer (32) that sprays hydrogen chloride (33) to flue gas from a coal combustion boiler (11) that uses coal as a fuel (F); NOx removing apparatus (13) that removes nitrogen oxides by ammonia denitration by adding ammonia (12) to the flue gas after spraying hydrogen chloride and oxidizes mercury; an air preheater (14) that recovers heat in the gas after removal of nitrogen oxides; a precipitator (15) that removes particulates in the gas; an activated carbon atomizer (22) that sprays activated carbon (22a) into the gas after particulate collection; a bag filter (21) that collects activated carbon having adsorbed mercury; a desulfurizer (16) that removes sulfur oxides in the flue gas after removal of activated carbon; a stack (17) that discharges the gas which has undergone desulfurization to outside; and an ORP meter (19) that measures an oxidation reduction potential for feeding air to a slurry absorbent in the desulfurizer (16).
摘要:
A method and system are disclosed for achieving reduced mercury emissions from a power plant at a minimum cost. The parameters of the combustion chamber and a sorbent injector are manipulated to control the residual carbon in ash and the injected sorbent. These two elements combine to reduce mercury in the exhaust gas to an acceptable level.
摘要:
A method and system for automated control of the operating temperature setpoint of a circulating fluidized bed (CFB) scrubber within a pre-determined range of approach temperatures to the adiabatic saturation temperature of the CFB scrubber exhaust stream to maintain an optimal operating temperature, thereby reducing low temperature sulfuric acid corrosion and deposition of wet materials, and high temperature excess reagent use. A Dewcon® Moisture Analyzer (or equivalent) is connected in the exhaust stream of the CFB scrubber. The Dewcon® Moisture Analyzer transmits adiabatic saturation temperature data of the exhaust stream to the CFB scrubber system controller. Based on pre-programmed parameters, the system controller adjusts the CFB scrubber temperature setpoint.
摘要:
A method for reducing the emissions from combustion gases produced during a combustion process includes injecting a hydrocarbon-based reducing agent into the combustion gases to form a combustion gas mixture. The combustion gas mixture including oxides of nitrogen, NOx, is directed through a selective catalyst reduction (SCR) system including a catalyst bed to remove NOx from the combustion gas mixture and to produce an exhaust gas. In one embodiment, the exhaust gases are released from the SCR to the atmosphere.
摘要:
A system is provided that prevents inhibition of adsorption of Hg and other heavy metals by activated carbon or other heavy metal adsorbent due to prior adsorption of sulfur trioxide (SO3) in an exhaust gas containing SO3. As it has been found that while SO3 is adsorbed, the adsorption of SO3 precedes the adsorption of Hg and other heavy metals onto activated carbon, a basic substance injection system is disposed along an exhaust gas flow channel at an upstream side of an activated carbon injection system, thereby attaining effective removal of Hg and other heavy metals from the exhaust gas by adsorption thereof onto surface pores of the activated carbon. The SO3 concentration after removal by basic substance conversion is computed from the SO3 concentration before removal, and the activated carbon injection rate can be controlled based on the concentration after removal.
摘要:
An air pollutant control system comprises: a denitration apparatus that reduces nitrogen oxide in flue gas discharged from a coal combustion boiler, and that sprays hydrogen chloride into the gas to oxidize mercury, an air heater that recovers heat in gas, a dust collector that reduces dust in gas, a desulfurization apparatus that reduces sulfur oxide in gas from which the dust has been reduced, a hydrogen chloride vaporizer that evaporates concentrated hydrochloric acid to obtain the hydrogen chloride, and a hydrochloric acid neutralization tank where dilute hydrochloric acid discharged from the hydrogen chloride vaporizer or the concentrated hydrochloric acid is neutralized with an alkali agent. Neutralized chloride is supplied to a fuel feeder, mixed with a fuel, and then burned as a fuel in a boiler to produce hydrogen chloride in flue gas. Together with sprayed hydrogen chloride derived from the hydrogen chloride vaporizer, the mercury is reduced.
摘要:
The invention provides methods and apparatuses for removing carbon dioxide from a gas stream. In particular, the invention provides methods and apparatuses for absorbing carbon dioxide from a coal-fired boiler flue gas stream using an absorbing solution and for regeneration of an alkaline component used in the absorbing solution. In one embodiment, the invention provides a method for removing carbon dioxide from a gas stream by contacting a gas stream containing carbon dioxide with an alkaline liquid stream; absorbing at least a portion of the carbon dioxide into the alkaline liquid stream to produce absorbed carbon dioxide; and catalyzing a reaction of the absorbed carbon dioxide to a form of carbonate.