RU2334113C1 - Microturbine - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: microturbine incorporates an electrochemical reactor containing a high-temperature fuel element batteries, cut in between the compressor and turbine in the turbocharger gas-air stage. The said turbocharger represents a commercially available supercharger used for piston engine supercharging.

EFFECT: higher efficiency, lower costs, faster repair.

1 dwg

Description

The invention relates to gas turbine power sources, and in particular to small gas turbine units - microturbines, and can be used in energy, as well as in automobile, railway, water, air transport as part of electric power plants.

Known low-power gas turbine units - microturbines, designed, as a rule, for the basic power supply of isolated consumers or backup power supply for responsible consumers in the presence of other sources of electricity [1]. Known microturbines used in transport, for example, a gas turbine generator GTG-100K for marine power plants [2].

An example of a microturbine for ground use is the GTG-100M gas turbine generator [2], which consists of a gas turbine engine and a generator connected by an elastic coupling. A gas turbine engine consists of a turbocompressor made in the form of a single-stage centrifugal compressor and a three-stage axial turbine located on a common shaft, a tubular countercurrent combustion chamber, a gearbox with drive units and support systems. A compressor, a combustion chamber and a turbine with inlet and exhaust devices form the gas-air path of the engine.

The disadvantages of the known microturbines are:

- low electrical efficiency (within 10-25% for simple cycle microturbines of the GTG-100M type [2] and up to 30% for the most advanced regenerative cycle microturbines of the type Capstone C30, C60 [1]) and, accordingly, low profitability;

- the high structural complexity of the microturbine as a whole and of individual units — the compressor, turbine, combustion chamber — and, accordingly, the high cost, and with the transition to the regenerative cycle to increase the efficiency, the cost of the microturbine significantly increases.

To eliminate the drawbacks, it is necessary to achieve more efficient use of fuel and increase electrical efficiency, as well as simplifying the design by reducing the number of rotating nodes and nodes operating in high temperature conditions, maximizing the use of cheap and affordable parts and nodes.

This goal is achieved by the fact that the microturbine is made in the form of two modules: a turbocompressor and an electrochemical reactor installed in the gas path between the compressor and the turbine instead of the combustion chamber, and a relatively cheap serial turbocompressor unit used for turbocharging piston engines is used as a turbocompressor. The electrochemical reactor contains sections of high-temperature fuel cells (for example, solid oxide - SOFC, or melt-carbonate - MCFC, or other types) of direct oxidation of hydrocarbon fuel or with internal conversion of hydrocarbon fuel; or sections of fuel cells operating on synthesis gas with a high content of free hydrogen and fuel processors for processing hydrocarbon fuel into synthesis gas. The electrochemical reactor can be based on serial fuel cells, for example, MTU and other manufacturers [3, 4]. A turbocompressor unit ensures the operation of an electrochemical reactor — supplying compressed air and exhausting exhaust gases containing reaction products — by utilizing the energy of the exhaust gases by the turbine without taking off the electricity generated by the electrochemical reactor.

The use of this invention allows to achieve the following results:

1) increase efficiency by 2-3 times or more compared to known microturbines by achieving electrical efficiency of 45-65% or more, depending on the type of fuel cells and fuel composition, which also exceeds the achieved level of efficiency of piston engines.

2) cost reduction due to the use of relatively cheap and affordable serial units and assemblies, the minimum number of rotating parts (lack of gear and generator); increase the resource of nodes and assemblies due to the lower temperature in the gas-air tract when replacing the combustion chamber with an electrochemical reactor;

3) the possibility of quick repair by replacing the main components (turbocompressor unit, fuel cell sections) due to the modular design directly at the site of operation of the microturbine by personnel with the minimum required qualifications.

The drawing shows a diagram of a microturbine.

The microturbine consists of a turbocompressor 1 and an electrochemical reactor 2 with an inverter (converter) 3 of direct current to alternating current. The turbocharger 1 is made in the form of a serial turbocharger unit used for turbocharging piston engines, and consists of a compressor 3 and a turbine 4, the impellers of which are located on a common shaft.

Compressor 4 and turbine 5 are located in a common housing, while the channels of compressed air from the compressor and the supply of hot gases to the turbine communicate with the electrochemical reactor 2, forming a single gas-air path. The compressor of a serial turbocompressor unit with a degree of pressure increase equal to 2.0-2.5 ensures the use of low-pressure household gas microturbines as the main fuel, without the use of an additional booster gas compressor.

Microturbine works as follows. The start-up is carried out by spinning the shaft of the turbocharger 1, for example, by supplying compressed air to the blades of the impeller of the compressor 4. The air compressed by the rotating compressor enters the electrochemical reactor 2, where hydrocarbon fuel and, if necessary, water are also supplied. The heating of the air-fuel mixture to create the conditions for the necessary electrochemical reactions to occur can be carried out, for example, by a catalytic heater located in the electrochemical reactor 2. As a result of electrochemical reactions of direct oxidation of hydrocarbon fuel or internal conversion of hydrocarbon fuel followed by oxidation of hydrogen, the fuel cells of the electrochemical reactor 2 the release of electrical and thermal energy. Electric energy is released in the form of direct current, which is then converted in the inverter 3 into alternating current with the characteristics required by the consumer. Hot exhaust gases with a temperature of 600-650 ° C (for fuel cells type MCFC) or 800-1000 ° C (for fuel cells type SOFC) enter turbine 5, where they expand, performing mechanical work. The compressor 4 is driven from the turbine 5 through the shaft. After the turbine, exhaust gases can be emitted into the atmosphere or can enter the external heat recovery circuit.

Natural gas can be used as microturbine fuel, incl. low-pressure household gas, or synthetic combustible gases of various compositions, biogas, depending on the type of fuel cells used. In the course of further development of fuel cell technology, the use of liquid hydrocarbon fuels is possible.

1. Catalog of gas-turbine equipment - 2006. Rybinsk, Yaroslavl region, CJSC "Gas-turbine technologies", 2006 - p. 4, 126-128, 234.

2. A. Gubich. The use of low-power gas turbine engines in the energy sector / Gas Turbine Technologies, No. 6, November-December 2001 - pp. 30-31. (prototype)

3. I.V. Maslov. High-temperature fuel cells - cogeneration energy sources of the future / Turbines and diesel engines, No. 1, January-February 2006 - p. 4-6.

4. E.A. Zakharenko, V.D. Burov. Efficient Small Energy: Fuel Cells / Turbines and Diesels, No. 4, July-August 2006 - pp. 40-43.

Claims (1)

A microturbine, characterized in that an electrochemical reactor is installed between the compressor and the turbine in the gas-air path of the turbocompressor, containing batteries of high-temperature fuel cells, and the turbocompressor is made in the form of a serial turbocompressor unit used for turbocharging piston engines.