Exxon Research and Engineering Company

Energy and Environmental Research

General Electric Company

Ge Energy and Environmental Research Corporation

Richard Kenneth Lyon

Anthony M Dean

James E Hardy

Anthony J DeGregoria

Boyd E Hurst

Vitali Victor Lissianski

Roy Payne

William J Metrailer

Jerald Alan Cole

Vladimir M Zamansky

William R Thomas

Andrew Kaldor

Howard Freund

Charles Rebick

Philip N Eisner

An apparatus for burning coal to produce substantially pure hydrogen for use in fuel cells, together with 'sequestration ready' carbon dioxide and a stream of oxygen depleted air for powering gas turbines. The apparatus includes two fluidized bed reactors and a third transfer line reactor. The first reactor is supplied with coal particles or 'char' and fluidized with high temperature steam. The second reactor is fluidized with high temperature steam and the third reactor is fluidized by compressed air. Solids circulated among these three reactors include a mixture of materials containing coal, calcium compounds (present as CaO, CaCOand mixtures thereof) and iron compounds (present as FeO, FeOand mixtures thereof).

Apparatus for converting coal into fuel cell quality hydrogen and sequestration-ready carbon dioxide

A new cost effective and thermally efficient process for converting nearly valueless resources, such as &ldquo;static,&rdquo; lower quality sour natural gas containing hydrogen sulfide, to useable fuels and chemicals, such as hydrogen, methanol and high cetane diesel fuel. The preferred method and apparatus can be used to treat conventional sour gas, i.e., gas having a ratio of H S to CH of at least 0.1 moles and preferably of at least 0.33 moles/mole, using a reforming catalyst and a sulfur capture agent. The process nominally can be carried out using two reactors that repeatedly cycle reactants between two basic process steps&mdash;reforming, and air regeneration.

Conversion of static sour natural gas to fuels and chemicals

A method for recovering large volumes of hydrocarbon fuels, particularly methane (CH ), using commercially available reagents which are strongly water-soluble and soluble in liquid CO in the presence of liquid CO injected into the methane hydrate formation. The reagents which are strongly water-soluble and soluble in liquid CO form dilute aqueous acids that significantly increase the rate of conversion of methane hydrate into methane and CO hydrate, thereby allowing the natural gas to be released in a form that can then be recovered in large quantities using conventional devices. The preferred embodiment uses SO , HCl or other strongly water soluble gas to cause the methane hydrate ice crystals to melt and form an aqueous solution. The aqueous solution contacts the methane hydrate ice on one side and liquid carbon dioxide on the other side. The system spontaneously adjusts so that the acid solution remains strong enough to melt the methane ice, but not strong enough to prevent the formation of the carbon dioxide ice at the recovery temperature and pressure. The natural gas is liberated from the hydrate and removed by conventional devices.

Catalyst allowing conversion of natural gas hydrate and liquid CO2 to CO2 hydrate and natural gas

A process for burning coal to produce substantially pure hydrogen for use in fuel cells, together with &ldquo;sequestration ready&rdquo; carbon dioxide and a stream of oxygen depleted air for powering gas turbines, characterized by using a combination of two fluidized bed reactors and a third transfer line reactor, the first reactor being supplied with coal particles or &ldquo;char&rdquo; and fluidized with high temperature steam; the second reactor being fluidized with high temperature steam and the third reactor being fluidized by compressed air. Solids circulated among these three reactors include a mixture of materials containing calcium compounds (present as CaO, CaCO and mixtures thereof) and iron compounds (present as FeO, Fe O and mixtures thereof). The coal is gasified by the steam in the presence of CaO to produce CaCO and relatively pure hydrogen for use in fuel cells per a CO acceptor process. Because only part of the coal char input to the first reactor is gasified to produce hydrogen, the remainder can be burned to supply thermal energy necessary to regenerate the CaCO back to CaO. Carbon in the middle bed fluidized bed reactor reacts with Fe O in the third reactor and the temperature in the middle fluidized bed reactor is sufficiently high to decompose CaCO back into CaO.

Process for converting coal into fuel cell quality hydrogen and sequestration-ready carbon dioxide

A process of oxidizing an ash and sulfur containing fuel such as coal in order to power gas turbines using a material such as the oxides of iron which in an oxidized state can be readily reduced and which in a reduced state is readily oxidized. Preferably, the oxides of iron are circulated between two fluid bed reactors and reduced by the ash and sulfur containing fuel in the first said fluid bed reactor and oxidized by air in the second said fluid bed reactor, with ash and SO in the gases leaving chiefly from the first said fluid bed reactor. The temperature is controlled within the second said fluid bed reactor by use of a clean fuel and the rate of addition of the ash and sulfur containing fuel to the second fluid bed is controlled so as to limit the amount of SO in the gases leaving the second said fluid bed.

Method for efficient and environmentally clean utilization of solid fuels

An improved method of burning low sulfur coal in order to power gas turbines using unmixed combustion that ensures virtually complete oxidation of the coal, with the sulfur content of the coal being recovered as elemental sulfur for use as recycle in the unmixed combustion process. An unmixed combustion catalyst is circulated between two fluid bed reactors and becomes reduced by low sulfur coal in the first fluid bed reactor and oxidized by air in the second fluid bed reactor. The first reactor produces carbon-containing fly ash which is then separated and contacted with gases containing SO from the first fluid bed reactor to produce CO , CO, H S, COS, CS , and elemental sulfur. The elemental sulfur is separated and a portion thereof recycled back to the first fluid bed reactor.

Unmixed combustion of coal with sulfur recycle

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.

Thermally limited selective oxidation methods and apparatus

Methods are provided for decreasing the amount of nitrogen oxides released to the atmosphere as a component of combustion emissions. The methods are carried out by forming a combustion flue gas in a combustion zone, the combustion flue gas including nitrogen oxides, injecting overfire air and droplets of a solution or a powder of a selective reducing agent into a burnout zone, and contacting the combustion flue gas with the overfire air and the selective reducing agent in the burnout zone to thereby decrease the concentration of nitrogen oxides therein. The selective reducing agent is provided in an aqueous solution or powder which is injected into the overfire air in optimized droplet or particle form prior to or concurrently with injection of the overfire air into the burnout zone.

Method of reducing NOx in a combustion flue gas

An improved methods and systems are provided for transferring heat in a combustion system. The methods and systems provide for alternately exposing a reducing gas and a gas containing molecular oxygen to an unmixed combustion catalyst to respectively reduce and oxidize the unmixed combustion catalyst. The unmixed combustion catalyst is readily reducible when in its oxidized state and is readily oxidized when in its reduced state. The alternating reduction and oxidation reactions enable the unmixed combustion catalyst to efficiently release heat to a heat receiver in efficient thermal contact with the unmixed combustion catalyst. In most embodiments of the present invention, the unmixed combustion catalyst is in a reactor bed of a combustion system.

Methods and systems for heat transfer by unmixed combustion

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.

Method and apparatus for unmixed combustion as an alternative to fire

A method and apparatus are provided for oxidizing unoxidized fuel in combustion systems in which the air and fuel are not completely and uniformly mixed, the average air fuel ratio being sufficient for complete oxidation, but portions not containing sufficient air for complete oxidation. A bed of a readily reducible metal oxide, the reduced form of this metal oxide being readily oxidized, is placed within the combustion system. The air and fuel are passed through the bed at an elevated temperature, the metal oxide oxidizing those portions not containing sufficient air for complete combustion, and then being reoxidized by those portions which contain more than sufficient air for complete combustion.

Method and apparatus for prevention of puffing by rotary kiln and other

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.

Self-scrubbing removal of submicron particles from gaseous effluents

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.

Methods for reducing NO.sub.x emissions from combustion effluents

It has been found that trace concentrations of organic materials, including toxic organic compounds, oxidize slowly. Safe and reliable incineration of toxic organic compounds at low concentration is provided by injecting a clean fuel such as H.sub.2, CH.sub.4, or CO into the incinerator combustion chamber to promote rapid oxidation of the toxic organic compounds. It is believed that the clean fuel added to the combustion effluents raises the total concentration of fuel and organic materials above the second oxidation threshold so that the toxic organic compounds are rapidly destroyed.

Apparatus and methods for incineration of toxic organic compounds

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 present invention is also related to a method for preventing the formation of H.sub.2 SO.sub.4 in the absence of ammonia or its precursors. The formation of these corrosive substances is extremely detrimental. NH.sub.4 HSO.sub.4 formation is a limitation upon the usefulness of nitric oxide reduction processes, particularly in boilers, furnaces, and other combustion devices. The formation of H.sub.2 SO.sub.4 limits effective heat recovery in combustion equipment. 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. By eliminating SO.sub.3, the formation of NH.sub.4 HSO.sub.4 and H.sub.2 SO.sub.4 can be blocked. The present invention teaches contacting the methanol with the combustion effluent at a temperature ranging from approximately 500.degree. C. to about 950.degree. C. in order to assure proper operation of the process. It is also important to limit the reaction time used so that the carbon monoxide produced by the methanol oxidation is not itself oxidized to carbon dioxide.

Growing community of inventors

Pittstown, NJ, United States of America

Richard Kenneth Lyon