519results about "Combustion using catalytic material" patented technology

A combustor method and apparatus is provided. The method utilizes flameless combustion with one or more of three improvements to enhance ignition of the flameless combustor. A catalytic surface can be provided within a combustion chamber to provide flameless combustion at least in the vicinity of the catalytic surface at a temperature that is much lower than the autoignition temperature of fuel in air without the presence of the catalytic surface. Nitrous oxide or supplemental oxygen may also be used as an oxidant either instead of air or with air to reduce ignition temperatures. Further, electrical energy can be passed through the fuel conduit, raising the temperature of the conduit to a temperature above which the fuel will ignite when combined with the oxidant.

A burner assembly includes a catalyzed burner for combusting an anode exhaust stream from a polymer electrolyte membrane (PEM) fuel cell power plant. The catalysts coated onto the burner can be platinum, rhodium, or mixtures thereof. The burner includes open cells which are formed by a lattice, which cells communicate with each other throughout the entire catalyzed burner. Heat produced by combustion of hydrogen in the anode exhaust stream is used to produce steam for use in a steam reformer in the PEM fuel cell assembly. The catalyzed burner has a high surface area wherein about 70-90% of the volume of the burner is preferably open cells, and the burner has a low pressure drop of about two to three inches water from the anode exhaust stream inlet to the anode exhaust stream outlet . The burner assembly operates at essentially ambient pressure and at a temperature of up to about 1,700° F. (646° C.). The burner assembly can combust anode exhaust during normal operation of the fuel cell assembly. The burner assembly also includes an adjunct burner which can combust gasoline or anode bypass gas (the latter of which is a reformed fuel gas which is tapped off of the fuel cell stack fuel inlet line) during startup of the fuel cell power plant. Once start up of the fuel cell power plant is achieved, the burner assembly will need only combustion of the anode exhaust by the catalytic burner to produce steam for the reformer.

A combustor method and apparatus is provided. The method utilizes flameless combustion with one or more of three improvements to enhance ignition of the flameless combustor. A catalytic surface can be provided within a combustion chamber to provide flameless combustion at least in the vicinity of the catalytic surface at a temperature that is much lower than the autoignition temperature of fuel in air without the presence of the catalytic surface. Nitrous oxide or supplemental oxygen may also be used as an oxidant either instead of air or with air to reduce ignition temperatures. Further, electrical energy can be passed through the fuel conduit, raising the temperature of the conduit to a temperature above which the fuel will ignite when combined with the oxidant.

This invention relates generally to uses of novel nanomaterial composition and the systems in which they are used, and more particularly to nanomaterial compositions generally comprising carbon and a metal, which composition can be exposed to pulsed emissions to react, activate, combine, or sinter the nanomaterial composition. The nanomaterial compositions can alternatively be utilized at ambient temperature or under other means to cause such reaction, activation, combination, or sintering to occur.

According to one aspect, a method of controlling a multi-combustor catalytic combustion system is provided for determining a characteristic of a fuel-air mixture downstream of a preburner associated with a catalytic combustor and adjusting the fuel flow to the preburner based on the characteristic. The characteristic may include, for example, a measurement of the preburner or catalyst outlet temperature or a determination of the position of the homogeneous combustion wave in the burnout zone of the combustor.

The present invention generally relates to processes for production of ethanol from cellulosic biomass. The present invention also relates to production of various co-products of preparation of ethanol from cellulosic biomass. The present invention further relates to improvements in one or more aspects of preparation of ethanol from cellulosic biomass including, for example, improved methods for cleaning biomass feedstocks, improved acid impregnation, and improved steam treatment, or “steam explosion.”

Integrated Combustion Reactors (ICRs) and methods of making ICRs are described in which combustion chambers (or channels) are in direct thermal contact to reaction chambers for an endothermic reaction. Superior results were achieved for combustion chambers which contained a gap for free flow through the chamber. Particular reactor designs are also described. Processes of conducting reactions in integrated combustion reactors are described and results presented. Some of these processes are characterized by unexpected and superior results.

A device and a method for flame stabilization in a burner (10), includes a burner housing at least partially enclosing a burner volume, into which may be introduced via at least one fuel line, fuel, and via at least one air feed means, air, forming an air / fuel mixture spreading in a preferred flow direction, which may be ignited in a combustion chamber (11) connecting downstream of the burner housing to form a stationary flame (13). Upstream of the flame (13), a catalyst arrangement (1) is provided through which an air / pilot fuel mixture (4), separate from the air / fuel mixture, is flowable. The catalyst arrangement (1) has at least two catalyst stages which are located one behind the other in the through-flow direction, of which the catalyst stage (3) located upstream, the so-called POX-catalyst, is flow-washable by the air / pilot fuel mixture (4) with an air / pilot fuel mixture ratio λ<1, by which catalyst stage (3) the air / pilot fuel mixture (4) is partially oxidized, and of which catalyst stages the downstream catalyst stage (8), the so-called FOX-catalyst, is flow-washable by a leaned air / pilot fuel mixture (7) with a mixture ratio λ>1, by which the leaned air / pilot fuel mixture is completely oxidized forming an inert hot gas flow (9).

A catalyst element (30) for high temperature applications such as a gas turbine engine. The catalyst element includes a metal substrate such as a tube (32) having a layer of ceramic thermal barrier coating material (34) disposed on the substrate for thermally insulating the metal substrate from a high temperature fuel / air mixture. The ceramic thermal barrier coating material is formed of a crystal structure populated with base elements but with selected sites of the crystal structure being populated by substitute ions selected to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a higher rate than would the base compound without the ionic substitutions. Precious metal crystallites may be disposed within the crystal structure to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a lower light-off temperature than would the ceramic thermal barrier coating material without the precious metal crystallites.

In one embodiment, a system includes a fuel nozzle that includes a fuel injector that includes a fuel port and a premixer tube. The premixer tube includes a wall disposed about a central passage, multiple air ports extending through the wall into the central passage, and a catalytic region. The catalytic region includes a catalyst, disposed inside the wall along the central passage, configured to increase a reaction of fuel and air.

A coated article (e.g., 244) and a method for preparing a coating (e.g., 400) for a metallic substrate (402) are described. In one embodiment, the method includes preparing a ceramic powder comprising particles of a ceramic material (404) doped with a catalyst species (406). The method also includes adding metal particles (408) and the ceramic powder to a fluid to form a fluid suspension effective to maintain the catalyst species dispersed therein, and then applying the fluid suspension to the metallic substrate to form the coating thereon. In another embodiment, an aqueous suspension of undoped ceramic particles (316) may be combined with a fluid suspension of metallic particles to form the coating.

Catalytic system combining an aluminium or iron containing catalytic support, a rare earth containing porous deposit, carbon nanoparticles and a carbon containing structure making bonds between carbon nanoparticles.

Methods and apparatus for control of NOx in catalytic combustion systems, and more particularly to control of thermal or / and prompt NOx produced during combustion of liquid or gaseous fuels in the combustor sections of catalytic combustor-type gas turbines, by controlled injection of water in liquid or vapor form at selected locations, orientations, amounts, rates, temperatures, phases, forms and manners in the compressor and combustor sections of gas turbines. The ratio of thermal NOx ppm reduction to water addition, in weight %, is on the order of 4-20, with % NOx reduction on the order of up to about 50-80% and NOx of below 2 ppm. Liquid water, steam or superheated steam can be used to reduce NOx in combustion systems operating at reaction zone temperatures above 900° C., preferably 1400° C. to 1700° C. The amount of water added is sufficient to provide a concentration of water in the range of from about 0.1% to about 20% by weight of the total air and fuel mixture flowing into the post catalyst reaction zone. Water is introduced simultaneously or sequentially in a plurality of locations, at selected rates, amounts, temperatures, forms, and purity, preferably in accord with a suitable control algorithm.

The invention provides a catalyst for thermal decomposition of an organic substance having the form of spherical granule having a particle diameter of 0.1 to 1.2 mm, a pore volume of 0.1 to 0.3 mL / g, a tap density of 1.05 to 1.4 g / mL, and a wear rate of 2% by weight or less, the catalyst being obtained by mixing and granulating a pulverized product of an inorganic oxide exemplified by titanium oxide with at least one sol selected from a titania sol, a silica sol, an alumina sol, and a zirconia sol to make spherical granules, calcining the spherical granules at a temperature from 400 to 850° C., and sieving the calcined granules.

Integrated Combustion Reactors (ICRS) and methods of making ICRs are described in which combustion chambers (or channels) are in direct thermal contact to reaction chambers for an endothermic reaction. Particular reactor designs are also described. Processes of conducting reactions in integrated combustion reactors are described and results presented. Some of these processes are characterized by unexpected and superior results, and / or results that can not be achieved with any prior art devices.

The invention provides a catalyst for thermal decomposition of an organic substance having the form of spherical granule having a particle diameter of 0.1 to 1.2 mm, a pore volume of 0.1 to 0.3 mL / g, a tap density of 1.05 to 1.4 g / mL, and a wear rate of 2% by weight or less, the catalyst being obtained by mixing and granulating a pulverized product of an inorganic oxide exemplified by titanium oxide with at least one sol selected from a titania sol, a silica sol, an alumina sol, and a zirconia sol to make spherical granules, calcining the spherical granules at a temperature from 400 to 850° C., and sieving the calcined granules.

Catalytic system combining an aluminium or iron containing catalytic support, a rare earth containing porous deposit, carbon nanoparticles and a carbon containing structure making bonds between carbon nanoparticles.

The present invention generally relates to processes for production of ethanol from cellulosic biomass. The present invention also relates to production of various co-products of preparation of ethanol from cellulosic biomass. The present invention further relates to improvements in one or more aspects of preparation of ethanol from cellulosic biomass including, for example, improved methods for cleaning biomass feedstocks, improved acid impregnation, and improved steam treatment, or “steam explosion.”

A system comprising a compressor (10) having an inlet stream (25) and an outlet stream (26), a pre-heater (12) having a process inlet stream (29) and a process outlet stream (31), a catalytic combustor (13) having an inlet stream (32) and an outlet stream (33) and containing an catalyst, and a turbine (14) having an inlet stream (34) and an outlet stream (35), wherein, the outlet stream (26) of the compressor(10) is connected to the process inlet stream (29) of the pre-heater (12), the process outlet stream (31) of the pre-heater (12) is connected to the inlet stream (32) of the catalytic combustor (13). The outlet stream (33) of the catalytic combustor (13) is connected to the inlet stream (34) of the turbine (14). During operation of the system, the inlet stream (25) of the compressor (10) has a substantially constant and low concentration of fuel.

The present invention relates to a method and an apparatus (6) for carrying out the method, the method being used for combustion of a fuel-oxidator mixture in a combustion chamber (7) of a turbogroup, in particular of a power plant. A total oxidator flow (12) is divided into a main oxidator flow (14) and a secondary oxidator flow (15). The main oxidator flow (14) is lean mixed with a main fuel flow (21) in a premix burner (8), and the mixture (23) is fully oxidized in the combustion chamber (7). The secondary oxidator flow (15) is divided into a pilot oxidator flow (17) and a heat-exchanging oxidator flow (18). The pilot oxidator flow (17) is rich mixed with a pilot fuel flow (22), and the mixture (17, 22) is partially oxidized in a catalyst (24), with hydrogen being formed. Downstream of the catalyst (24), the partially oxidized pilot fuel-oxidator mixture (25) and the heat-exchanging oxidator flow (18) are together introduced into at least one zone (26) which is suitable for stabilizing the combustion of the main fuel-oxidator mixture (23).

A control system for a catalytic combustion system on a gas turbine includes a flame preburner, a fuel injector positioned downstream of the preburner and a catalyst positioned downstream of the fuel injector. In such systems, a portion of the fuel combusts within the catalyst itself and the remainder of the fuel combusts in a homogeneous combustion process wave downstream of the catalyst. A sensor in communication with the control system monitors the homogeneous combustion process wave and adjusts the gas temperature at the catalyst inlet to a preferred value based on a predetermined schedule that relates the catalyst inlet gas temperature to operating fundamentals such as adiabatic combustion temperature or the gas turbine's exhaust gas temperature.

A system comprising a compressor (10) having an inlet stream (25) and an outlet stream (26), a pre-heater (12) having a process inlet stream (29) and a process outlet stream (31), a catalytic combustor (13) having an inlet stream (32) and an outlet stream (33) and containing an catalyst, and a turbine (14) having an inlet stream (34) and an outlet stream (35), wherein, the outlet stream (26) of the compressor(10) is connected to the process inlet stream (29) of the pre-heater (12), the process outlet stream (31) of the pre-heater (12) is connected to the inlet stream (32) of the catalytic combustor (13). The outlet stream (33) of the catalytic combustor (13) is connected to the inlet stream (34) of the turbine (14). During operation of the system, the inlet stream (25) of the compressor (10) has a substantially constant and low concentration of fuel.

Residual fuels, as well as lighter distillate fuels, are combusted with greater efficiency by utilizing low concentrations of specific bimetallic or trimetallic fuel-borne catalysts. The catalysts reduce fouling of heat transfer surfaces by unburned carbon while limiting the amount of secondary additive ash which may itself cause overloading of particulate collector devices or emissions of toxic ultra fine particles when used in forms and quantities typically employed. By utilizing a fuel containing a fuel-soluble catalyst comprised of platinum and at least one additional metal comprising cerium and / or iron, production of pollutants of the type generated by incomplete combustion is reduced. Ultra low levels of nontoxic metal combustion catalysts are able to be employed for improved heat recovery and lower emissions of regulated pollutants.

The present invention relates to a method for mixing at least two separate fluid flows (2, 3), in particular for a burner of a power plant. To improve the mixing, a plurality of swirl flows (7, 8), which are annular and concentric with respect to a longitudinal center line (6), are generated from the fluid flows (2, 3), in such a manner that radially adjacent swirl flows (7, 8) have opposite directions of rotation.

A circulation fluidized-bed boiler of rich-oxygen combustion type is prepared as utilizing circulation fluidized-bed boiler with external fluidized bed heat exchanger to carry out combustion in mode of mixing mixture gas of high concentration oxygen from air separate and recirculation smoke from boiler tail with fuel, controlling load and firepot temperature of said boiler by regulating flow rate of fly ash particles entering into external fluidized bed heat exchanger.

A combustion system for a gas turbine engine includes a Catalyst (CAT) combustion sub-system for generating combustion products under a lean premixed fuel / air condition in the presence of a Catalyst and a Dry-Low-Emissions (DLE) combustion sub-system, for generating combustion products under a lean premixed fuel / air condition. Gaseous and liquid fuels are used for the DLE combustion sub-system while only gaseous fuel is used for the CAT combustion system. The engine operates at start-up and under low load conditions with the DLE combustion system and switches over the combustion process to the CAT combustion sub-system under high load conditions. Thus the combustion system according to the invention combines the advantages of DLE and CAT combustion processes so that the gas turbine engine operates over an entire operating range thereof at high engine efficiency while minimizing omissions of nitrogen oxides and carbon monoxide from the engine.

A gas turbine power system for generating energy by means of a gas turbine cycle, wherein heat energy is more effectively used by burning the exhaust gases (109) and the partial oxidation of said exhaust gases (109) is achieved by means of a hypostoichiometric amount of air and steam fed into a catalytic reactor (107) to form a first oxidation stage followed downstream in said turbine (103) by additional oxidation occurring in a power turbine (104) or downstream therefrom, said power turbine being in turn arranged downstream from the catalytic reactor (107). Catalytic partial oxidation may be performed using a supply of an initiating agent, particularly hydrogen. The method is remarkable in that the hydrogen fed into the reactor inlet through an injector (113) is provided by recycling part of the effluent from the reactor, the power turbine or a reforming reactor for reforming part of the fuel gas with a large excess amount of steam for performing catalytic partial oxidation.

An auxiliary electrical power supply includes a fuel combustor passively sourced with fuel for combusting fuel and a thermoelectric generator close-coupled to the combustor for converting the heat from the combustor to electric power.