Abstract: An apparatus and method for high velocity injection of a stream of fluid fuel into a stream of NOx containing combustion effluents downstream of a primary combustion zone, without the use of recirculated flue gas or other carrier gas. The apparatus includes a fuel introducing member that has a fuel receiving end for receiving fluid fuel from a fuel source and a fuel injection end for injecting the fluid fuel into the stream of combustion effluents. A fuel passage is in fluid communication with the fuel receiving end and the fuel injection end of the fuel introducing member. A means for increasing the velocity of the fluid fuel, without the need of a carrier gas, is associated with the fuel introducing member.

Abstract: A method and apparatus are provided for selectively oxidizing carbon monoxide in the presence of hydrogen gas while leaving the hydrogen substantially unoxidized. This method utilizes a catalytic material, such as copper/copper oxide, silver/silver oxide, nickel/nickel oxide, and the higher and lower oxides of cerium, which in a more oxidized state is readily reduced by carbon monoxide and which in a more reduced state is readily oxidized by air. A carbon monoxide/hydrogen gas mixture and air are alternately contacted with the catalytic material, such that the carbon monoxide is selectively oxidized and the catalytic material is regenerated.

Abstract: Various methods for decreasing the amount of nitrogen oxides released to the atmosphere as a component of combustion gas mixtures are provided. The methods specifically provide for the removal of nitric oxide and nitrogen dioxide (NOx) from gas mixtures emitted from stationary combustion systems. In particular, methods for improving efficiency of nitrogen oxide reduction from combustion systems include injecting metal-containing compounds into the main combustion zone and/or the reburning zone of a combustion system. The metal containing compounds react with active combustion species, and these reactions change radical concentrations and significantly improve NOx conversion to molecular nitrogen. The metal-containing additives can be injected with the main fuel, in the main combustion zone, with secondary or reburning fuel addition, or at several locations in the main combustion zone and reburning zone.

Abstract: A self cleaning port system and method provides for removal of ash deposits and build-up from around a port opening in a combustion device such as an industrial or utility furnace or boiler. The self cleaning port system includes a port structure for providing communication between a source of injected material and an interior portion of the combustion device. The port structure can be a burner for injecting fuel and air, an overfire air port, a flue gas recirculation port, a reburning port for injecting a reburning fuel, a pollutant emission control port for injecting NO.sub.x or SO.sub.2 reduction agents, or other types of ports. A blowing member such as a lance is disposed within or formed as part of the port structure and is configured to discharge a blowing medium so as to remove ash deposits adjacent to the port opening. The blowing medium is discharged from the blowing member such that the blowing medium is directed outwardly away from the port opening.

Abstract: A process for oxidizing fuel and transferring the heat produced to a particular use in a combustion system such as fuels conversion. A bed of a mixture of materials forming an unmixed combustion catalyst, which in an oxidized state is readily reducible and in a reduced state is readily oxidizable, is placed in efficient thermal contact with a heat receiver for use in the combustion system. Fuel and air are alternately contacted with the bed, whereby the fuel is oxidized, the air is depleted of oxygen, and heat is liberated. The heat is efficiently transferred to the heat receiver by careful selection of the materials of the bed such that the temperatures produced when the fuel is oxidized and when the air is depleted of oxygen are advantageous to the particular use in the combustion system.

Abstract: A method and system for the use of waste coal fines to reduce nitrogen oxides emissions from a coal-fired cyclone boiler. A coal water slurry including waste coal fines is injected as a co-firing fuel into a cyclone barrel of the cyclone boiler to partially oxidize the coal water slurry in a central portion of the cyclone barrel where injected. This produces a reducing zone having reducing gas species that convert nitrogen oxides to diatomic nitrogen. The coal water slurry can alternatively be injected into the cyclone barrel from a secondary combustion air conduit. The evaporation of the water from the coal water slurry reduces the overall combustion temperature in the cyclone barrel, further reducing the production of nitrogen oxides.

Abstract: A method and system is provided for the reduction of nitrogen and sulfur oxides emissions from carbonaceous fuel combustion flue gases. The method includes the injection of coal water slurry as a reburn fuel into furnace flue gases to partially oxidize the coal water slurry thereby producing reducing gas species in a reburn zone that convert flue gas nitrogen oxides to diatomic nitrogen. Optionally, sulfur oxides may also be removed from the flue gas by adding alkali compounds to the coal water slurry before injecting the slurry into the furnace, or by injecting the alkali compounds separately into the reducing reburn zone in the furnace created by the partial oxidation of the coal water slurry reburn fuel. The alkali compounds react with the sulfur species to produce alkali sulfite and sulfate particulate solids, which can be removed in a downstream particulate removal device such as an electrostatic precipitator or bag house.

Abstract: A process and system for reducing cold start NO.sub.x, carbon monoxide, and hydrocarbon emissions from mobile source engine exhaust utilizes adsorption and desorption of NO.sub.x compounds on a regenerable sorbent material. Molecules of NO.sub.x are adsorbed onto the sorbent material during the ineffective warm up period of a three-way catalytic converter. When the catalytic converter reaches operating temperatures, the NO.sub.x molecules are thermally desorbed from the sorbent material and delivered to the catalytic converter for effective reduction to molecular nitrogen.

Abstract: The present invention is related to methods and systems for preventing the release of nitrogen oxides with combustion flue gases emitted to the atmosphere. The invention is specifically directed to the removal of nitric oxide, nitrogen dioxide, and nitrous oxide from flue gas in stationary combustion systems. The methods of the invention improve efficiency of conventional reburning and advanced reburning processes by two key improvements, including the injection of a reducing agent into the reburning zone and the use of promoters, which considerably enhance NO.sub.x control. The promoters are metal-containing compounds that can be added to the reducing agents. These improvements allow either one or two stages of reducing agent injection for greater NO.sub.x control.

Abstract: A method is provided for preventing the release of air pollutants with combustion flue gases emitted to the atmosphere by the removal of one or more of nitric oxide, sulfur trioxide, light hydrocarbons, carbon monoxide, and trace amounts of mercury from combustion flue gas streams. The method converts nitric oxide to nitrogen dioxide, sulfur trioxide to sulfur dioxide, removes light hydrocarbons in the form of carbon dioxide, reduces the concentration of carbon monoxide, and removes mercury vapor in the form of mercury oxide, by the addition of hydrogen peroxide or a mixture of hydrogen peroxide and methanol to a combustion flue gas at a temperature in the range from about 650 K (377.degree. C.) to 1100 K (827.degree. C.).

Abstract: A process and system for reducing cold start NO.sub.x, carbon monoxide, and hydrocarbon emissions from mobile source engine exhaust utilizes adsorption and desorption of NO.sub.x compounds on a regenerable sorbent material. Molecules of NO.sub.x are adsorbed onto the sorbent material during the ineffective warm up period of a three-way catalytic converter. When the catalytic converter reaches operating temperatures, the NO.sub.x molecules are thermally desorbed from the sorbent material and delivered to the catalytic converter for effective reduction to molecular nitrogen.

Abstract: Methods and apparatus are provided for combustion systems wherein fuel may be burned completely with use of air as the oxidant, without the necessity for completely mixing the fuel with the air before, during, or after the combustion process. A bed of readily reducible metal oxide, the reduced form of this metal oxide being readily oxidized, is placed within a combustion system. The air and fuel are contacted with the bed at an elevated temperature, with the metal oxide oxidizing the fuel and being regenerated by the air. In one embodiment, complete combustion of fuel occurs without complete mixing of fuel and air. In other embodiments fuel can be burned with little or no mixing with a the combustion process, or fuel can be burned with little or no mixing with air, before, during, or after the combustion process, thereby avoiding a number of disadvantages of such mixing.

Abstract: The invention comprises a method and a system for separating very fine particulates from gaseous effluents resulting from the burning of coal or other fossil fuels, or from other combustion processes, such particulates being too small for typical methods to separate. The method utilizes the SO.sub.2, which normally occurs in such gaseous effluents, as a vehicle to enlarge the particles. The gaseous effluent is mixed with water droplets whereby some of the water evaporates; a gaseous ammonia is then injected into the mixture under conditions such as to cause ammonium sulfite to form and to condense on the particles, thus enlarging the particles, and water to condense on the particles, thus further enlarging them; and the now enlarged particles are separated from the gaseous effluent by known methods. DeNO.sub.x and DeSO.sub.x procedures may also be performed on the gaseous effluent prior to the process noted above. Likewise heat recovery may be effected.

Abstract: Techniques for enhancing the burnout zone chemistry for NO.sub.x reduction are disclosed. The key parameters for the enhancement of burnout zone chemistry are: (a) a reaction temperature in the range from about 1300.degree. F. to about 1900.degree. F., and optimally in the range from 1400.degree.-1700.degree. F.; (b) a carbon monoxide concentration below about 0.5 percent; and (c) the presence of nitrogenous reducing species. By controlling the stoichiometry associated with reburning to produce a slightly fuel-rich region for selective reducing agent injection, reductions can be achieved at relatively low temperatures which approach those obtained by conventional catalytic reduction.

Abstract: Methods for reducing NO.sub.x emissions from stationary combustion systems having variable flue gas temperatures and variable CO levels in the combustion effluents are disclosed. The present invention represents an improvement in the Thermal DeNO.sub.x process. Use of a condensed phase precursor of gaseous ammonia which causes a delay between initial mixing and reacting with the flue gas substantially reduces or eliminates the adverse effects of variable CO levels, and to a certain extent variable flue gas temperatures. Use of a condensed phase precursor of gaseous ammonia in combination with a second reducing agent dramatically increases the useful temperature range of the Thermal DeNO.sub.x process.

Abstract: Methods for reducing NO.sub.x emissions from stationary combustion systems having variable flue gas temperatures are disclosed. Use of an annonium salt of an organic acid enlarges the temperature window for effective selective noncatalytic NO.sub.x reduction thereby accounting for variable flue gas temperatures. Currently preferred ammonium salts of organic acids include ammonium formate, ammonium acetate, and ammonium oxalate. Mixtures of urea and either an ammonium salt of an organic acid or a metallic salt of an organic acid provide an even greater temperature window for NO.sub.x reduction. Currently preferred metallic salts of organic acids include Ca(COOH).sub.2, Ca(CH.sub.3 COO).sub.2, Ca(C.sub.2 H.sub.5 COO).sub.2, Mg(COOH).sub.2, Mg(CH.sub.3 COO).sub.2, and Mg(C.sub.2 H.sub.5 COO).sub.2.

Abstract: The present invention relates to methods for selectively reducing NO.sub.x so that nitrogen can be removed from emission effluent streams and NO.sub.x emissions can be reduced to very low levels. In addition, the present invention teaches a method whereby NO.sub.x and SO.sub.x may be simultaneously removed from the effluent stream.The present invention teaches the reduction of NO.sub.x with cyanuric acid. Initially, cyanuric acid is decomposed to form decomposition products. The reaction of cyanuric acid to produce its decomposition products, such as isocyanic acid or related reaction intermediates, takes place in an oxygen-free, fuel rich, decomposition zone with the reaction temperature in the range of from about 1000.degree. F. to about 3000.degree. F.After the cyanuric acid is decomposed in the absence of oxygen, the decomposition stream is mixed with the effluent stream containing NO.sub.x. At this point the oxygen level of the stream must be carefully controlled to provide an excess of oxygen.

Abstract: The present invention relates to methods for selectively reducing NO.sub.x so that nitrogen can be removed from emission effluent streams and NO.sub.x emissions can be reduced to very low levels. In addition, the present invention teaches a method whereby NO.sub.x and SO.sub.x may be simultaneously removed from the effluent stream.The present invention teaches the reduction of NO.sub.x with --NH and --CN containing selective reducing agents such as ammonium sulfate, urea, and NH.sub.3. Initially, the selective reducing agent is decomposed in a fuel-rich environment to form highly reactive decomposition products. The reaction of the selective reducing agent to produce its decomposition products, such as NH, NH.sub.2, and related reaction intermediates, takes place in an oxygen-free, fuel-rich decomposition zone with the reaction temperature in the range of from about 300.degree. F. to about 2400.degree. F.

Abstract: The present invention is related to a method for preventing the formation of NH.sub.4 HSO.sub.4 during the noncatalytic reduction of nitric oxide by ammonia or ammonia precursors in combustion effluents. The formation of this sticky and corrosive substance inside combustion units is an extreme limitation upon the usefulness of nitric oxide reduction processes, particularly in boilers, furnaces, and other combustion devices.The present invention specifically teaches the use of methanol to reduce SO.sub.3 in the effluent stream to SO.sub.2. The noncatalytic reduction of SO.sub.3 by methanol is selective in that a large fraction of the SO.sub.3 is converted to SO.sub.2, while on a percentage basis very little oxygen is consumed. In addition, the process of the present invention allows the amount of methanol to be limited such that significant amounts of carbon monoxide are not produced and emitted with the effluent stream.