INVENTION
Russian Federation Patent RU2277638

METHOD AND APPARATUS FOR POWER THROUGH THE USE OF CONDENSED FUEL

METHOD AND APPARATUS FOR POWER THROUGH THE USE OF CONDENSED FUEL

Name of the inventor: Kondra Evgeny (RU); Kochetkov Gennady Borisovich (RU); Rafe Vladimir (RU); Hush Anatoly Petrovich (RU); Fursov Viktor Prokofievich (RU)
The name of the patentee: Kondra Evgeny
Address for correspondence:. 141980, Moscow region, Dubna, Prospect Bogolyubov 6, kv.1303, EI Condrieu
Starting date of the patent: 2005.04.11

The invention relates to a method and apparatus for generating electrical energy by using condensed fuels in which the fuel is gasified in gasifier type tunnel furnace produced gas is burned in a furnace provided with a high-temperature heat exchanger and the heat of flue gas is used for the compressed heat air supplied to the combustion chamber of the gas turbine, resulting in an electrical generator. In accordance with the invention, fuel is moved by the gasifier to form therein one or more through channels, oriented predominantly along the direction of travel, is fed to the gasifying agent channel, and output them from the product gas. Gasifier reduction zone selected portion formed hydrogen through a hydrogen permeable membrane that is placed in said channel and supply it in the gas turbine combustor. The invention can be used as fuel to power a wide range of materials, substantially different in composition and properties (powders, lump materials, paste and liquids).

DESCRIPTION OF THE INVENTION

The present invention relates to methods and devices for producing electrical energy by gasification of condensed fuels, incineration of combustible gas resulting from the transfer of heat generated by the gas turbine working fluid, resulting in an electrical generator, wherein a portion of the combustible gas is used as gas turbine fuel.

Under condensed fuels in this application is meant containing free or chemically bonded carbon material of any origin, for example, fossil fuels (coal, peat, shale, tar sands, oil), industrial waste (waste coal or coal processing, fly ash CHP, waste wood, waste biomass, refinery wastes, sludge, rubber waste), municipal waste (sludge fields of filtration, household waste). The proposed method and apparatus allow to be used as fuel to generate electricity a wide range of materials, significantly different in composition and properties.

Among the known methods of producing electricity from condensed fuels is considered the most promising method is the so-called IGCC (Integrated Gasification and Combined Cicle) - fuel gasification to yield electricity in combined cycle (gasification - gas turbine - steam turbine). As noted in the materials of the US Department of Energy's Clean Coal Technology Program (Clean Coal Technology Program of US Department of Energy, Topical Report 21 - September 2001. Coproduction of Power, Fuels and Chemicals), a method based on IGCC technology are among the most efficient and clean modern technologies for producing energy from coal emissions, comparable to the emissions of power plants, fueled by natural gas. In addition to high environmental cleanliness and IGCC method allows to raise efficiency of power generation. For example, at a power plant in Polk County, Florida (IGCC-project of Tamra ELECTRIC) to the end of 2000 it was planned to bring the efficiency up to 38%, and in the largest IGCC demonstration project in Kentucky (The Kentucky Pioneer Energy IGCC Demonstration Project, The Kentucky Pioneer Energy, LLC, a subsidiary of Global Energy Inc.) founded design efficiency of 48% for the power capacity of 540 MWe, running on lignite.

High scores on environmental friendliness and efficiency of IGCC-projects are achieved through the use of complex and expensive equipment. Thus, the total cost of an IGCC project of Tamra-ELECTRIC in Polk County was 303 million US dollars (Clean Coal Technology Program of US Department of Energy, Topical Report 19 -. July 2000. Integrated Gasification Combined-Cycle Project An Update), that the capacity of 250 MWe, of supplied external customers, means the unit cost of capital cost of about US $ 1,200 per installed kilowatt of electricity. Fuel gasification plant for use in Polk County Texas method (high pressure gasification using oxygen blast) requiring a complicated preparation of the fuel gas before it is fed to the gas turbine (gas cooling, removal of fly ash and other harmful impurities). Another disadvantage of this scheme is the need for special preparation of the source of fuel (coal preparation of aqueous suspension based on the determined fractional composition of the fine coal).

A method of producing hydrogen and power from low grade solid fuel in the plasma ehnergotehnologicheskoj installation comprising gasification fuel in plasmachemical reactor, compressing the resulting synthesis gas in the compressor, its separation, the direction of synthesis gas in the steam generator to generate steam to produce electricity in a turbogenerator and node separation, consisting of two series-mounted membrane systems with the compressor in between, the first of which produce methane and synthesis gas is directed for combustion in a steam generator, and the second - from the synthesis gas produced hydrogen which is fed to the consumer or partially fed to the plasma-chemical reactor (RU 2055091, IPC C 10 J 3/18, 27.02.1996).

The disadvantage of this method is the complexity and high energy costs for operation of plasma chemical reactor.

A method of processing materials containing free or chemically bound carbon, whereby the fuel is gasified in an oxygen-containing gasifying agent countercurrently in the tunnel kiln type reactor (WO 2004/042278, IPC F 23 G 5/027, 21.05.2004). Before entering the reactor fuel is formed so that it, or between parts, or between the fuel and the inner wall of the reactor as it moves through the reactor to form one or more through channels, oriented predominantly along the direction of movement. In these feeds gasifying agent is fed to and from the product gas is withdrawn, allowing contact of the gasifying agent and / or the product fuel gas in finding them in the channel. This arrangement allows the process to gasify a wide range of fuels, significantly different in composition and properties (powders, lump materials, pasty materials and even liquid) without invoking specific for each type of fuel its processing operations.

The advantage of this method is the ease and reliability of the equipment used. However, the presence in the composition of the resulting combustible pyrolysis gas makes it difficult to use resins as fuel for the gas turbine.

The closest to the invention by the technical essence and achieved result in part of the method is a method of generating electricity by use of condensed fuels, comprising feeding the condensed fuel and the gasifying agent into the gasifier, having a reduction zone, receiving the gasifier product gas containing hydrogen formed in the reduction zone burning the product gas in the furnace to produce hot combustion gases, heat removal from the flue gases in a heat exchanger using a gas turbine as the generator drive for power generation, part of the hot exhaust gas which is used as a gasifying agent, and the remaining exhaust gas is used as oxidizer for burning product gas (RU 2211927, IPC F 01 K 13/00, 10.09.2003).

The closest to the invention by the technical essence and achieved result in part of the device is known from the same source device is generating electricity by use of condensed fuels, comprising a gasifier, means for introducing into it the condensed fuel and the gasifying agent, means the withdrawal from the reactor product gas and feed it into the furnace for combustion, provided with a heat exchanger for the selection of the flue gas heat, a gas turbine, which is a power generator driven for power generation and a compressor for compressing air and equipped with means for supplying part of the exhaust gases to the gasifier as a gasifying agent, and means for supplying the remaining exhaust gas as the oxidant a combustor for burning product gas.

The disadvantage of the known method and device is the narrow range of applications in the processing of brown coal.

The technical result in the achievement by the present invention is to overcome the disadvantages of the known method and apparatus using the gasification of condensed fuels to generate electricity, and allowing, allowing use as a fuel to power a wide range of materials, significantly different in composition and properties (powders, lumpy materials, liquid and pasty materials).

Said technical result is achieved in that according to the method of producing electricity by using condensed fuels fuel and the gasifying agent is fed to the gasifier having a reduction zone, is produced in the gasifier product gas containing hydrogen formed in the reduction zone is combusted product gas, produced hot flue gases are fed into the heat exchanger, the heat exchanger is taken from the flue gases, a gas turbine is used as a drive generator for generating electricity, part of the hot exhaust gas which is used as a gasifying agent, and the remaining exhaust gas is used as the oxidant for the combustion product- gas prior to feeding to the gasifier condensed fuel is formed so that it, or between parts of, or between the fuel and the inner wall of the gasifier while moving the material by the gasifier to form one or more through channels arranged mainly along the fuel moving direction by the gasifier in which supplied gasifying agent and which produce a product gas from a gasifier of the reduction zone are selected portion formed hydrogen through a hydrogen permeable membrane that is placed in said channel and supply it in a gas turbine combustor, heat removal from the flue gases in the heat exchanger is carried out by feeding a compressed air supply cooled by water injection and the direction of preheated compressed air into the gas turbine combustor.

To suppress the release of pyrolysis tar from fuel gasification and increase the yield of hydrogen by gasification tar condensed fuel and gasifying agent can be fed to the gasifier satellite, carrying it facing fuel gasification process.

To control the temperature conditions of the gasification process in the gasifier may be fed into the water between high temperature region and the end of the recovery zone of the gasifier, which is supplied to the gasifying agent.

To reduce the energy consumption for the supply of hydrogen to the combustion chamber of a gas turbine, the bleed of hydrogen from the gasifier can be cooled by air that is directed into the furnace for burning product gas.

The residual heat of flue gas after the heat exchanger can be utilized in a steam boiler and steam produced is directed to the turbine, generating electricity.

Said technical result is achieved in that the device for generating electricity by use of condensed fuels, comprising a gasifier, means for introducing into it the condensed fuel and the gasifying agent, means the withdrawal from the reactor product gas and feed it into the furnace for combustion, provided with a heat exchanger for removing heat flue gases, a gas turbine, which is power-driven generator to produce electricity and a compressor for compressing air and equipped with means for supplying part of the exhaust gases to the gasifier as a gasifying agent, and means for supplying the remaining exhaust gas as the oxidant in the furnace for burning the product gas, the gasifier is a tunnel furnace, and means for supplying therein the condensed fuel and gasifying agent are made so that when moving the material for the gasifier to form one or more through channels, oriented predominantly along the direction of movement of the material by the gasifier and adapted to ensure contact located therein gasifying agent a gasified fuel gasifier is provided with a hydrogen permeable membrane disposed in said channels to select part of the hydrogen formed in the reduction zone, and means supplying hydrogen to the gas turbine combustion chamber to compress the air compressor is connected to a heat exchanger for heating the compressed air cooled by water injection means and having an output preheated compressed air from the heat exchanger and feeding it into the gas turbine.

The gasifier may be provided with means for feeding water into it between the place of installation of said membrane and the end of the gasifier, which is supplied to the gasifying agent.

The apparatus may be provided with means for cooling the bleed air from the gasifier and means hydrogen feed this air to the furnace for burning product gas.

The furnace for burning the product gas can be paired with the steam boiler for the utilization of residual heat of the flue gases after the heat exchanger and boiler feeds the steam turbine, generating electricity.

The drawing shows a schematic diagram of an apparatus for the process for producing electricity by using condensed fuels.

METHOD AND APPARATUS FOR POWER THROUGH THE USE OF CONDENSED FUEL

A device for producing electricity by using fuel containing condensed gasifier 1, which is a tunnel furnace. The air as a gasifying agent can be used, or oxygen-enriched air or pure oxygen (oxidant). The use of oxygen improves the productivity of the process and the caloric content of the product gas, but it complicates the equipment and reduce production safety. The gasifying agent is fed to the gasifier in an amount insufficient for complete oxidation of the fuel, resulting in a reactor at high temperatures downstream of the gasifying agent from the place where the oxygen finishes completely formed recovery zone 2. In this zone formed on the surface of the fuel hot coke occur reduction reaction of carbon dioxide to CO and water vapor - up hydrogen.

supply means to the gasifier 1 condensed fuels can be in the form of platforms which are mounted on pallets placed on them with fuel. gasifying agent supply means are in the form of pipes with a regulating device mounted thereon. At the outlet of the gasifier 1 installed output means thereof the product gas and feed it into the furnace for incineration 3, 4 provided with a heat exchanger for taking heat of flue gases. The device is provided with a gas turbine 5, which is a power generator driven for power generation and a compressor 6 for compressing the air, and equipped with means for supplying part of the exhaust gases to the gasifier 1 as a gasifying agent, and means for supplying the remaining exhaust gas as the oxidant in the furnace for burning the product gas and 7 of the combustion chamber.

Gasifier 1 is provided with a hydrogen-permeable membrane 8 arranged in one or more through channels 9, the hydrogen supply means and the combustion chamber of the gas turbine 5. 7 as means for selecting the hydrogen can use vacuum pumps (not shown), and as the feeding means hydrogen into the combustion chamber of the gas turbine 5 7 - compressors. Through channels 9, oriented predominantly along the direction of movement of the material by the gasifier 1 and arranged to provide a contact which is in the gasifying agent to fuel gasified.

The compressor 6 for compressing air connected to the heat exchanger 4 for heating the compressed air cooled by water injection. output means preheated compressed air from the heat exchanger 4 and supply it to the gas turbine 5 are mounted on the conduit with its regulator (not shown).

1 A gasifier is provided with means for feeding water into it between the place of installation of said membrane 8 and the end of the gasifier 1, by means of gasifying agent. Means for supplying water may be formed as nozzles (not shown).

The apparatus may be provided with means for cooling the bleed air from the gasifier and one hydrogen of the air feeding means 3 in the furnace for burning product gas.

The furnace 3 for the combustion of the product gas can be interfaced with a boiler 10 for disposal of the residual heat of the flue gases after the heat exchanger 4, which can power the steam turbine 11 generating electricity.

A preferred process is as follows.

The process is carried out by feeding the fuel and oxygen-containing gasifying agent (oxidant) to the gasifier 1 type tunnel furnace. reduction zone 2 is formed after the initiation of the process, for example, placing on a platform fuel and submitting them to the middle of the reactor, where the material is ignited by the gasifying agent. You can place flammable material on the first platform (wood, peat, rags soaked with kerosene, etc.), which set fire to any source of open flame, resulting in the ignition and the working fuel.

After ignition, gradually advancing the platform with fuel in the gasifier 1, there is formed a high-temperature region, which begins from the resulting coke gasification fuel. As mentioned above, the part of the gasifying agent in the field there is complete consumption of oxygen contained therein, resulting in lower gas flow recovery zone 2 is formed form a temperature profile, particularly in the reduction zone, it depends on the type of fuel, its feed direction (right side or left side) and process the process mode but retains the major features, namely, the presence of the high temperature zone in the middle of the gasifier, and it ends to the substantial reduction of the gasifier. When the platform on which the ignition was performed, will pass from the middle to the end of the gasifier, simultaneously with the start of fuel in the gasifier and out therefrom recycling solids (ash) from the right side or the left side, respectively. In case the fuel supply towards the gasifying agent (so-called direct gasification process), the solid products of processing (hereinafter ash) from the gasifier will be output at a relatively low temperature due to cooling of a counter flow of relatively cool gasifying agent. The output of the gasifier with its opposite end product gas and will have a relatively low temperature by cooling the fuel supplied to meet. In the case where the fuel is fed into the gasifier in the same direction as the gasifying agent (a so-called inverted gasification process), the product gas and the ash will be removed from the gasifier with the opposite end of the gasifier at the same relatively high compared with direct temperature process.

In both cases, the main obstacle for the use of the resulting product gas as a fuel for gas turbines is the presence of dust and gas of pyrolysis tar. In the present invention, the technical solution to this problem is rejection of the product gas purification from dust and resins. Instead, one output of the gasifier product gas is fed to its combustion furnace 3 equipped with a heat exchanger 4 for removing heat produced flue gases and heating the compressed air, which is used as the working medium of the gas turbine 5. In order to increase the heat removal efficiency of the flue gas fed into the heat exchanger with compressed air, its temperature after compression by the compressor 6 is reduced by the required injection amount of water.

To reduce the proportion of the heat source of fuel transferred working fluid of the gas turbine through the heat exchanger 4, and thereby reduce its maximum operating temperature, without the loss of heat to use in the operating cycle of the turbine, the present invention provides selected from zone recovery part 2 formed therein hydrogen and fed to a gas turbine combustion chamber 7 5. Such a selection would reduce the calorific value of the product gas and to reduce its temperature in the combustion furnace 3, thereby reducing the requirements for high heat resistance of the heat exchanger design. The use for this purpose the hydrogen permeable membrane 8 ensures a complete absence of dust and tar in the pyrolysis gas and allows bleed without any purification to direct it in the combustion chamber 7 of the turbine 5. This solution allows transfer of the initial heat content of the condensed working fluid to the fuel gas turbine 5 in parallel in two ways: a) by burning resulting from the fuel "dirty" product gas containing tar pyrolysis compressed heat air supplied to the turbine, and b) through the selection of the reduction zone 2 of the gasifier 1 of environmentally friendly fuel for the turbine 5 - hydrogen. Selection of the hydrogen reduction zone 2 shifts the equilibrium towards its formation more, which allows more heat to transfer load from the heat exchanger 4 in the combustion chamber of the gas turbine 7 5. Due to the fact that the temperature in the reduction zone of the gasifier 1 is close to the optimum working temperature 8 metal membranes used for the separation of hydrogen (500-700 ° C), their use in the proposed scheme is simplified (no special heating membranes).

One or more channels 9 the desired shape and size can be formed, or between the fuel and the inner wall of the gasifier 1 through fuel placed on pallets, or between portions by placing these pieces on pallets one above the other to form between each pallet and the fuel placed on adjacent underlying pallet gap forming one of said channels.

The gas stream entering the channel is a gasifying agent, then along the length of the gasifier 1 as a result of heat exchange with the mass flow and the fuel surface within the channel 9, it is enriched gaseous processed products, turning in the product gas at the other end of the gasifier.

In the middle of the gasifier 1, regardless of the fuel feed direction, a region in which the inside of the channel missing both oxygen and resin pyrolysis, and in which the reactions of formation of CO and hydrogen through the interaction of coke to carbon dioxide and water vapor (recovery zone 2). In the case of the direct process (fuel supply toward the gasifying agent) formation of pyrolysis tar occurs below the zone 2 a gas stream, where they are separated from the fuel by heating it with hot gas stream containing no oxygen comes into the product gas and removed together with it from gasifier 1 as a mist towards fueling. In the case of pyrolysis fuel reversed process takes place between the end of the gasifier 1, which is supplied with fuel and the gasifying agent, and a zone of maximum temperature. Evolved volatile pyrolysis products are transported in the flow channel of the gasifying agent containing oxygen into the high temperature combustion zone, wherein the oxygen is consumed in oxidation reactions and where they are burned almost completely to form carbon dioxide and water vapor.

Thus, in both cases it is possible to place in the channels 8 of the membrane 9 to select the middle part of the hydrogen in the gasifier 1 in the reduction zone. With proper placement of membranes conditions for their work within the gasifier is almost perfect - the optimum temperature and the almost complete absence of impurities condensed from the gas stream.

It should be noted that by using inverse conversion process of gasification of the propellant takes place in the non-condensable gases more fully as substantially undergo gasification and pyrolysis and tar, which are carried in the direct process from the gasifier as a mist relatively cool product gas. For biomass fuels type, peat or lignite tar into a product-gas can reach 5-10% by weight. Their facing gasification process increases the concentration of hydrogen in the reducing zone in comparison with the direct process and thus allows in this case to increase the amount of bleed, or hydrogen, or lower energy costs for its selection.

When gasification energy-dense fuels with a low moisture content of the maximum temperature in the gasifier may be too high. To control the process temperature regime in the gasifier is fed water to the high temperature difference between the reduction region 2 and the end of the gasifier, which is served in the gasifying agent (oxidizer). Such a method of controlling a maximum temperature in the gasifier has an advantage, for example, compared to supplying steam to the gasifying agent because it eliminates the costs for production of steam heat.

To reduce the energy costs for compression of hydrogen withdrawn from the gasifier to supply it to the combustion chamber of the gas turbine can be cooled with air, hydrogen, which is then used as an oxidizing agent for burning the product gas in the combustion chamber 3.

To improve the efficiency of power generation part of the hot exhaust gases after the gas turbine 5 can be fed into the gasifier 1 as a part of gasifying agent.

The remaining exhaust gas turbine 5 can be used as an oxidizing agent for burning the product gas in the combustion chamber 3.

To reduce the heat loss to the environment with the flue gases leaving the heat exchanger 4 can be disposed of the residual heat of the flue gas in the boiler 10, and the generated steam is sent to turbine 11 generating electricity.

Thus, the method of generating electricity by use of condensed fuels and device for its implementation allow the use as a fuel for power plants wide range of materials, substantially different in composition and properties (powders, lump materials, paste and liquids).

CLAIM

1. A method of generating electricity by use of condensed fuels, comprising feeding the condensed fuel and the gasifying agent into the gasifier, having a reduction zone, obtaining a product in the gasifier - containing gas the hydrogen formed in the reduction zone, burning the product - the gas in the furnace to obtain hot combustion gases , heat removal from the flue gases in a heat exchanger using a gas turbine as the generator drive for power generation, part of the hot exhaust gas which is used as a gasifying agent, and the remaining exhaust gas is used as the oxidant for the combustion product - the gas, characterized in that, before feeding to a gasifier condensed fuel is formed so that it, or between parts of, or between the fuel and the inner wall of the gasifier while moving the material by the gasifier to form one or more through channels arranged mainly along the fuel moving direction by the gasifier to which is supplied gasifying agent and in which the product is formed - the gas from the gasifier of the reduction zone are selected portion formed hydrogen through a hydrogen permeable membrane that is placed in said channel and supply it in a gas turbine combustor, heat removal from the flue gases in the heat exchanger is accomplished by supplying compressed therein air cooled by water injection and the direction of preheated compressed air into the gas turbine combustor.

2. A method according to claim 1, characterized in that the condensed fuel and gasifying agent is supplied in cocurrent gasifier, carrying therein facing fuel gasification process.

3. The method of claim 1, wherein said water is fed to the gasifier at higher temperatures between the reduction zone and the end of the gasifier, which is supplied to the gasifying agent.

4. The method of claim 1, wherein the hydrogen withdrawn from the gasifier is cooled by air that is directed into the furnace for combustion product - gas.

5. The method according to claim 1, characterized in that the residual heat of the flue gases after the heat exchanger disposed in the boiler and the generated steam is directed to turbine that generates electricity.

6. A device for generating electricity by use of condensed fuels, comprising a gasifier, means for introducing into it the condensed fuel and the gasifying agent, means the withdrawal from the reactor product - the gas supply to the furnace for combustion, provided with a heat exchanger for heat transfer from the flue gases, a gas turbine, which is power-driven generator to produce electricity and a compressor for compressing air and equipped with means for supplying part of the exhaust gases to the gasifier as a gasifying agent, and means for supplying the remaining exhaust gas as the oxidant in the furnace for combusting the product - the gas, characterized in that said gasifier is a tunnel oven and means for supplying therein the condensed fuel and gasifying agent are made so that when moving the material for the gasifier to form one or more through channels, oriented predominantly along the direction of movement of the material by the gasifier and adapted to ensure contact located therein gasifying agent gasified fuel gasifier is provided with a hydrogen permeable membrane disposed in said channels to select part of the hydrogen formed in the reduction zone, and means supplying hydrogen to the gas turbine combustion chamber to compress the air compressor is connected to a heat exchanger for heating the compressed air cooled by water injection and having output means of preheated compressed air heat exchanger and feeding it into the gas turbine.

7. The apparatus of claim 6, wherein the gasifier is provided with means for feeding water into it between the place of installation of said membrane and the end of the gasifier by means of gasifying agent.

8. Apparatus according to claim 6, characterized in that it is provided with means for cooling the bleed air from the gasifier and means hydrogen feed of air into the furnace for combusting product - gas.

9. Apparatus according to claim 6, characterized in that the burner for burning product - involves gas steam boiler for recovery of residual heat of flue gases after the heat exchanger, and feeds the boiler steam turbine that generates electricity.

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Publication date 11.01.2007gg