CN104533621B - A kind of double fuel steam injection forward and reverse Gas Turbine Combined-cycle - Google Patents

Abstract

A steam injection forward and reverse gas turbine combined cycle using clean fuel and biomass dual fuel. The gas turbine adopts the form of regenerative steam injection-reverse gas turbine combined cycle, and uses clean fuel; the smoke generated by the combustion of biomass fuel in the boiler The gas first indirectly heats the air entering the gas turbine combustor, and then preheats the air entering the boiler. Among them, the steam generated by the gas turbine cycle can be used for external heating. The invention utilizes the cascade utilization principle of energy, and organically combines the external combustion method and the advanced steam injection forward and reverse Brayden cycle through system integration, which can greatly improve the energy utilization efficiency of biomass fuel, and the ratio of biomass to clean fuel can be adjusted. And realize the self-balancing of steam injection water consumption and recycled water.

Description

A dual-fuel steam injection forward and reverse gas turbine combined cycle

technical field

The invention relates to the technical field of gas turbines, in particular to a dual fuel steam injection forward and reverse gas turbine combined cycle.

Background technique

A simple cycle gas turbine consists of a compressor, a combustor and a gas turbine (turbine for short). The compressor continuously draws in air from the atmosphere and compresses it. The compressed air enters the combustion chamber, mixes with the injected fuel, and burns to become high-temperature gas, which then flows into the turbine and expands to do work, pushing the turbine impeller to rotate together with the compressor impeller, and the residual work is used as the output mechanical work of the gas turbine and generate electricity. The gas temperature before the turbine inlet is called the initial gas temperature. In order to make full use of the exhaust waste heat of the gas turbine, a waste heat boiler is generally installed at the rear of the gas turbine to generate steam and perform work in the steam turbine, thus forming a gas-steam combined cycle.

When the steam generated by the boiler is injected back into the combustion chamber of the gas turbine, it is mixed with the gas to heat and expand to do work, which constitutes a steam injection cycle. Compared with the combined cycle, the characteristics and advantages of the steam injection cycle are also very prominent: the efficiency of the steam injection cycle is slightly lower, but the specific work is higher; since the steam reinjection inhibits the formation of nitrogen oxides in the combustion process, the emission of pollutants is reduced; The steam turbine and condenser are removed, the system structure is simple, and the cost is reduced; when the steam generated by the waste heat boiler is supplied to the outside, the cogeneration of heat and power can be realized, and the thermoelectric adjustment range is large; the startup and shutdown are fast, and the operation is simple and easy. Maintenance; good partial load performance, strong ability to quickly track the load; small footprint. On the other hand, due to air humidification, water (steam) is discharged to the atmosphere along with the smoke exhaust, and the system needs to replenish new water from time to time, which consumes a lot of water. It is difficult to achieve the self-balancing of water recovery and water consumption. This hinders the development of steam injection cycle to some extent.

Generally, the pressure of the flue gas discharged from the turbine is only slightly higher than the atmospheric pressure, and the higher part is only used to overcome the exhaust resistance generated by the rear waste heat recovery device and other components. At this point, the gas turbine cycle is a forward (heat engine) cycle. When the pressure of the flue gas discharged from the gas turbine turbine is deliberately set below atmospheric pressure, followed by an isobaric cooling process and a compression process of the flue gas, the forward cycle and reverse compression process of the upper gas turbine constitute the so-called Forward and reverse gas turbine combined cycle. Due to the existence of the isobaric cooling process before the flue gas is recompressed, the water in the flue gas condenses, the flow rate of the flue gas decreases, and the power consumption of the flue gas recompressed from below the atmospheric pressure to the atmospheric pressure is much less than that of the flue gas from the atmospheric pressure in the turbine. The expansion work of expanding to below atmospheric pressure; due to the existence of the reverse cycle, the optimal pressure ratio of the cycle decreases; due to the decrease of the pressure ratio, the compression work of the fuel decreases. Due to the existence of these factors, under the same conditions, the efficiency of the entire combined cycle can be increased by about 1 to 2 percentage points compared with the simple forward cycle. For cycles with high steam content in the flue gas, such as various water injection cycles, steam injection cycles, etc. Especially effective. At the same time, the water condensed in the flue gas can also be replenished in the circulation, which greatly overcomes the natural defect of the circulation that consumes water.

The energy utilization of biomass fuel generally has two ways: combustion and gasification. The gas produced by gasification can be directly used in the combustion chamber of a gas turbine or an internal combustion engine. However, there are still problems such as the difficulty in purifying the gas after gasification, the large investment and low efficiency of the entire gasification power generation system. For example, as far as biomass is concerned, there is currently the capacity to build MW-level biomass gasification power generation projects, but the power supply efficiency of the system is only about 15%, and the applicability of gasification technology to various types of biomass is not strong. In terms of combustion and utilization of biomass fuel, fluidized bed or circulating fluidized bed boilers have wide fuel adaptability, high combustion efficiency, and outstanding environmental protection performance (thanks to relatively low-temperature combustion, staged air supply, and furnace desulfurization measures) ), strong peak shaving ability, and high operating economy, which have unique advantages. However, limited by the characteristics of biomass fuel, combustion temperature, and the small system scale limited by factors such as collection radius, the biomass steam power generation system with circulating fluidized bed boiler as the core also has the disadvantage of low power generation efficiency. At present, the scale of the largest biomass circulating fluidized bed combustion power generation system is about 130t/h, and its power supply efficiency does not exceed 32%.

Combining biomass combustion with efficient and clean gas turbines is a new way to utilize biomass. Among them, the focus of the research is on the biomass external combustion gas turbine cycle, and its integration method is generally as follows: the exhaust gas of the gas turbine enters the biomass boiler, and the high-temperature flue gas generated by the combustion of biomass and gas turbine exhaust enters a high-temperature boiler. The gas-gas heat exchanger heats the air discharged from the compressor into the combustion chamber in the gas turbine cycle, and essentially replaces the original clean fuel of the gas turbine with biomass. However, limited by the material of the high-temperature gas-gas heat exchanger, the air outlet temperature of the heated heat exchanger generally cannot exceed 900°C, resulting in the power supply efficiency of the external combustion gas-steam combined cycle at the current technical level. Nor will it exceed 32%.

Contents of the invention

The purpose of the present invention is to provide a dual-fuel steam injection forward and reverse gas turbine combined cycle that can greatly improve the energy utilization efficiency of biomass fuel, and realize the self-balancing of steam injection water consumption and water recovery in the cycle.

In order to achieve the above object, the dual-fuel steam injection forward and reverse gas turbine combined cycle provided by the present invention includes:

Air enters from the air input end of the compressor;

The output end of the compressor is connected with the air input end of the gas regenerator and the cooling air input end of the turbine;

The air output end of the gas regenerator is connected with the air input end of the boiler gas-gas heat exchanger;

The air output end of the boiler gas-air heat exchanger is connected to the air input end of the combustion chamber, and the clean fuel for heating the air enters from the fuel input end of the combustion chamber;

The flue gas output end of the combustion chamber is connected with the flue gas input end of the turbine;

The flue gas output end of the turbine is connected with the flue gas input end of the gas regenerator;

The flue gas output end of the gas regenerator is connected with the flue gas input end of the superheater;

The flue gas output end of the superheater is connected with the flue gas input end of the evaporator;

The flue gas output end of the evaporator is connected with the flue gas input end of the economizer;

The flue gas output end of the economizer is connected to the hot flue gas input end of the flue gas reheater, and the condensed water is led out from the flue gas reheater;

The hot flue gas output end of the flue gas reheater is connected to the flue gas input end of the flue gas cooler, and the condensed water is led out from the flue gas cooler;

The flue gas output end of the flue gas cooler is connected with the flue gas input end of the exhaust compressor;

The flue gas output end of the exhaust compressor is connected to the cold flue gas input end of the flue gas reheater, and the heated cold flue gas is discharged from the cold flue gas discharge end of the flue gas reheater;

Waste heat boiler feed water enters from the water input end of the economizer;

The water output end of the economizer is connected with the water input end of the evaporator;

The saturated steam output end of the evaporator is connected to the saturated steam output end of the superheater;

The superheated steam output end of the superheater is connected with the superheated steam input end of the combustion chamber;

The waste heat boiler is composed of superheater, evaporator and economizer connected in sequence;

Biomass fuel for heating the air enters from the fuel input of the boiler;

The flue gas output end of the boiler is connected with the flue gas input end of the boiler gas-gas heat exchanger;

The flue gas output end of the boiler gas-gas heat exchanger is connected to the flue gas input end of the boiler air preheater, and the flue gas output from the flue gas output end of the boiler air preheater is emptied;

The air required for boiler combustion enters from the air input end of the boiler air preheater;

The air output end of the boiler air preheater is connected with the air input end of the boiler;

The residual work after deducting the compression work of the compressor and exhaust compressor from the expansion work of the turbine drives the generator to run.

Wherein, the flue gas at the outlet of the turbine is lower than the atmospheric pressure, which is 0.1-0.95 bar.

Among them, the flue gas reheater and the flue gas cooler are equipped with condensed water recovery devices, and the recovered condensed water can be used as feed water for waste heat boilers after treatment.

Among them, the flue gas cooler is equipped with a cooling water cooler, the water input end of the cooling water cooler is connected to the water output end of the flue gas cooler, and the water output end of the cooling water cooler is connected to the water input of the flue gas cooler through a water pump end connection.

Among them, a water drop filter is set between the flue gas output end of the flue gas cooler and the flue gas input end of the exhaust compressor, and the flue gas output end of the flue gas cooler passes through the water drop filter and is connected with the flue gas of the exhaust compressor. connected to the gas input.

Among them, the superheated steam generated from the superheater is introduced into the combustion chamber for external heating.

Among them, the boiler refers to a fluidized bed or circulating fluidized bed boiler in which fuel and air are adiabatically combusted and no water cooling wall is arranged in it, and the furnace temperature of the boiler is 650-850°C.

Among them, a desulfurizer is added to the fluidized bed or circulating fluidized bed boiler.

Among them, the clean fuel includes one or more of natural gas, synthetic gas, liquefied petroleum gas, various distilled oils, methanol, and ethanol.

Compared with prior art, the present invention has following advantage:

1) Due to the comprehensive adoption of measures such as steam injection cycle, gas reheating, and forward and reverse cycle coupling, the combined cycle efficiency of gas turbines has been greatly improved and emissions have been reduced;

2) The boiler flue gas inlet temperature of the boiler gas-gas heater is up to 850°C, which is fully achievable with the current technical level, so that the external combustion method and the high-efficiency gas turbine cycle are organically combined, so that the equivalent power generation efficiency of biomass is greatly improved;

3) After the turbine outlet gas is cooled, a large amount of water condenses out, which can realize the self-balancing of steam injection water consumption and water recovery.

4) Since the air required for biomass fuel combustion does not depend on gas turbine exhaust, the ratio of biomass fuel to clean fuel can be varied within a wide range during system design to cope with different fuel supply conditions. Calculations show that the ratio of heat released by the combustion of biomass fuel and clean fuel can vary between 1 and 0.1, and the lower the ratio, the higher the conversion efficiency of biomass.

In a word, the invention utilizes the cascade utilization principle of energy, which can greatly improve the energy utilization efficiency of biomass fuel, the ratio of biomass to clean fuel can be adjusted, and the self-balancing of recycled water and water consumption can be ensured.

Description of drawings

Fig. 1 is the schematic diagram of the specific embodiment of dual-fuel steam injection forward and reverse gas turbine combined cycle of the present invention;

Fig. 2 is a schematic diagram of the working process of the dual-fuel steam injection forward and reverse gas turbine combined cycle of the present invention.

Explanation of symbols in the attached drawings:

Compressor 1, combustion chamber 2, turbine 3, superheater 4, evaporator 5, economizer 6, flue gas reheater 7, flue gas cooler 8, droplet filter 9, exhaust compressor 10, water pump 11. Cooling water cooler 12, gas regenerator 13, boiler 14, boiler gas-gas heater 15, boiler air preheater 16, generator 17.

detailed description

Please refer to Fig. 1, the dual-fuel steam injection forward and reverse gas turbine combined cycle of the present invention comprises:

The air enters from the air input end of the compressor 1; the output end of the compressor 1 is connected with the air input end of the gas regenerator 13 and the cooling air input end of the turbine 3; the air output end of the gas regenerator 13 is connected with the boiler gas - the air input end of the gas heat exchanger 15 is connected; the air output end of the boiler gas-air heat exchanger 15 is connected with the air input end of the combustion chamber 2; the clean fuel for heating the air enters from the fuel input end of the combustion chamber 2 ; The flue gas output end of combustion chamber 2 is connected with the flue gas input end of turbine 3; the flue gas output end of turbine 3 is connected with the flue gas input end of gas regenerator 13; the flue gas output of gas regenerator 13 connected to the flue gas input end of the superheater 4; the flue gas output end of the superheater 4 is connected to the flue gas input end of the evaporator 5; the flue gas output end of the evaporator 5 is connected to the flue gas input end of the economizer 6 ; The flue gas output end of the economizer 6 is connected with the hot flue gas input end of the flue gas reheater 7, and the waste heat boiler is composed of the superheater 4, the evaporator 5 and the economizer 6 connected in sequence; The hot flue gas output end of the flue gas recuperator 7 is connected to the flue gas input end of the flue gas cooler 8; the condensed water is led out from the flue gas cooler 8; the flue gas cooler 8 The flue gas output end is connected with the flue gas input end of the droplet filter 9; the flue gas output end of the water droplet filter 9 is connected with the flue gas input end of the exhaust compressor 10; the flue gas output end of the exhaust compressor 10 is connected with the flue gas The cold flue gas input end of the gas reheater 7 is connected; the heated cold flue gas is discharged from the cold flue gas discharge end of the flue gas reheater 7; the waste heat boiler feed water enters from the water input end of the economizer 6; The water output end of the economizer 6 is connected to the water input end of the evaporator 5; the saturated steam output end of the evaporator 5 is connected to the saturated steam output end of the superheater 4; the superheated steam output end of the superheater 4 is connected to the combustion chamber 2 The superheated steam input end is connected; the superheated steam output by the superheater 4 can also be used for external heating; the water output end of the water pump 11 is connected to the water input end of the cooling water cooler 12; the water output end of the cooling water cooler 12 is connected to the flue gas The water input end of the cooler 8 is connected so as to circulate the cooling water; the water output end of the flue gas cooler 8 is connected with the water input end of the water pump 11; the biomass fuel for heating the air enters from the fuel input end of the boiler 14; The flue gas output end of the boiler 14 is connected to the flue gas input end of the boiler gas-gas heat exchanger 15; the flue gas output end of the boiler gas-gas heat exchanger 15 is connected to the flue gas input end of the boiler air preheater 16; The flue gas output from the flue gas output end of the boiler air preheater 16 is evacuated; the air required for boiler combustion enters from the air input end of the boiler air preheater 16; the air output end of the boiler air preheater 16 is connected to the boiler 14 is connected to the air input end; the residual work after the expansion work of the gas turbine turbine 3 deducts the compression work of the compressor 1 and the exhaust compressor 10 drives the generator 17 to run.

On the basis of the above, the flue gas reheater and flue gas cooler of the present invention are equipped with condensed water recovery devices, so that the water vapor in the flue gas is condensed in the flue gas reheater and flue gas cooler. , reduce the consumption of steam injection cycle water.

The present invention also includes a water drop filter, the water drop filter is arranged between the flue gas cooler and the exhaust compressor, the flue gas output end of the flue gas cooler is connected to the input end of the exhaust compressor after passing through the water drop filter, In order to filter the water droplets in the flue gas before entering the exhaust compressor, and reduce the damage of water droplets to the exhaust compressor.

In the present invention, the superheated steam generated from the waste heat boiler can be introduced into the combustion chamber, and can also be used for external heat supply to realize cogeneration of heat and power.

Please refer to FIG. 2 , which is a schematic diagram of the working process of the dual-fuel steam injection forward and reverse gas turbine combined cycle of the present invention.

In steam injection forward and reverse gas turbine combined cycle, the compressor is used to continuously inhale air from the atmosphere, compress and pressurize the air, most of the compressed air enters the gas regenerator, and a small part of the compressed air enters the turbine as cooling air; The combustion chamber is used to convert the chemical energy contained in the incoming clean fuel into heat energy through a combustion chemical reaction to form high-temperature flue gas, which enters the turbine; the turbine converts the energy in the flue gas into mechanical energy, and part of the mechanical energy is used It is used to drive the compressor and the exhaust compressor, and the remaining part is converted into electric energy through the generator; the exhaust gas from the gas turbine at the outlet of the turbine is introduced into the gas regenerator to heat the air entering from the outlet of the compressor; it comes out of the gas regenerator The exhaust gas of the gas turbine enters the waste heat boiler, and heats the feed water of the waste heat boiler into superheated steam; the exhaust gas of the gas turbine from the waste heat boiler enters the gas reheater, and heats the exhaust gas of the gas turbine introduced from the exhaust compressor; The gas turbine exhaust from the exhaust gas cooler enters the flue gas cooler; the gas turbine exhaust from the flue gas cooler enters the exhaust compressor; the gas turbine exhaust from the exhaust compressor enters the flue gas reheater and is heated back emptying;

The boiler system is used to convert the chemical energy contained in the incoming biomass fuel into heat energy through combustion chemical reaction to form high-temperature boiler flue gas; the high-temperature boiler flue gas enters the boiler gas-gas heater; the boiler gas-gas heater is used to convert The air introduced from the gas regenerator is indirectly heated, and the heated air is introduced into the combustion chamber of the gas turbine; the boiler flue gas discharged from the boiler gas-gas heater enters the boiler air preheater; the boiler air preheater is used to convert the boiler combustion The required air is heated, and the preheated air is introduced into the boiler; the boiler exhaust is discharged through the boiler air preheater.

Part of the air compressed by the compressor is used for turbine cooling, and the rest is indirectly heated by the gas regenerator and boiler gas-gas heater to reduce clean fuel consumption; the air output by the boiler gas-gas heater enters the combustion chamber The high-temperature flue gas is formed, and then enters the turbine to do work and drives the generator to generate electricity. The gas turbine flue gas at the outlet of the turbine is lower than the atmospheric pressure, so as to increase the turbine output; Superheated steam, the superheated steam is output through the steam output end of the waste heat boiler and injected into the combustion chamber to improve the working ability of the gas turbine and reduce the generation of NO _X during the combustion process of the combustion chamber; the flue gas output from the waste heat boiler is input into the flue gas for reheating The lower-temperature flue gas output by the exhaust compressor is heated by the exhaust compressor so that it can be discharged into the atmosphere; the flue gas output by the flue gas reheater enters the flue gas cooler for cooling, which is used to cool the flue gas to a near-ambient temperature to reduce Subsequent exhaust compressor compression work; the flue gas output by the flue gas cooler enters the exhaust compressor, and the flue gas is compressed to a pressure greater than the atmospheric pressure after overcoming the resistance of the flue gas reheater, so that the flue gas can be discharged. The high-temperature flue gas produced by biomass combustion in the boiler first enters the boiler gas-gas heater to heat the air entering the combustion chamber to replace the original clean fuel of the gas turbine, and efficiently utilize the energy of biomass through the gas turbine cycle; through the boiler gas- The flue gas output by the gas heater enters the boiler air preheater to heat the air entering the boiler to improve boiler efficiency; the boiler flue gas output by the boiler air preheater is emptied.

In the present invention, the proportion of cooling air entering the turbine depends on the front temperature of the turbine and the cooling technology of the turbine, and is generally about 12% to 25%; the pressure at the outlet of the turbine is lower than the atmospheric pressure; the gas turbine exhaust at the outlet of the turbine The gas regenerator is introduced to heat the air entering from the outlet of the compressor to improve the cycle efficiency; the exhaust gas from the gas turbine from the gas regenerator enters the waste heat boiler to heat the feed water of the waste heat boiler into superheated steam, which can be introduced into the combustion chamber It is used to drive the turbine to do work, and it can also be used for external heat supply; the exhaust gas from the gas turbine from the waste heat boiler enters the gas reheater, and reheats the exhaust gas from the exhaust compressor to make the exhaust gas temperature higher than Certain environmental protection requirements, the water vapor in the flue gas is condensed in the flue gas reheater, and the condensed water is recovered; the exhaust gas from the gas turbine from the gas reheater enters the flue gas cooler to cool the flue gas to near ambient temperature, In order to reduce the compression work of the subsequent exhaust compressor, the water vapor in the flue gas continues to condense in the flue gas cooler, and the condensed water is recovered; the cooling water is sent to the cooling water cooler, and the cooled cooling water is sent back to the flue gas for cooling The gas turbine exhaust gas output from the flue gas cooler passes through the water drop filter to remove water droplets in the gas; the gas turbine exhaust gas output through the water drop filter enters the exhaust compressor to compress the gas turbine exhaust gas enough After overcoming the resistance generated by the flue gas reheater flowing through it, it is slightly higher than the atmospheric pressure to provide sufficient driving force for the chimney, which is conducive to the diffusion of the flue gas and meets environmental protection requirements; the exhaust gas from the gas turbine from the exhaust compressor It enters the flue gas reheater and is emptied after being heated. The boiler system converts the chemical energy contained in the incoming biomass fuel into thermal energy through combustion chemical reaction to form high-temperature boiler flue gas, which enters the boiler gas-gas heater; the boiler gas-gas heater is used to convert the The air introduced by the regenerator is indirectly heated, and the heated air is introduced into the combustion chamber of the gas turbine to realize the integration of the gas turbine cycle and the biomass combustion system; the boiler flue gas discharged from the boiler gas-gas heater enters the boiler air preheater; the boiler The air preheater is used to heat the air required for the combustion of the boiler to reduce the loss of exhaust smoke, and the preheated air is introduced into the boiler; the exhaust gas from the boiler output by the boiler air preheater is emptied.

The dual-fuel steam injection forward and reverse gas turbine combined cycle of the present invention includes the following technical links:

1) Air compression: when the air flows through the compressor to boost the pressure, the outlet temperature also rises, which requires work;

2) Combustion: Fuel mixes with air in the combustion chamber or boiler to undergo a chemical reaction, chemical energy is released, and the temperature rises;

3) Work done by gas expansion: high temperature and high pressure gas expands and works in the turbine, reducing temperature and pressure;

4) Waste heat recovery: The gas with waste heat at the outlet of the turbine passes through the waste heat recovery device to generate superheated steam, which can be injected into the combustion chamber and expanded in the subsequent turbine to do work, and can also be used for external heat supply;

5) Heat exchange: heat transfer between high-temperature fluid and low-temperature liquid to achieve the purpose of heat recovery and utilization;

6) Flue gas condensation: The water vapor in the flue gas is partially condensed due to the drop in heat exchange temperature of the flue gas, and latent heat is released during the condensation process;

7) Water drop filter: The cooled air enters the water drop filter to remove the water droplets entrained in the air and reduce the damage of water droplets to the compressor.

8) The flue gas is exhausted to the atmosphere.

The theoretical basis and principle of the dual-fuel steam injection forward and reverse gas turbine combined cycle of the present invention are:

1) Regeneration cycle: In a simple cycle, the exhaust temperature of the turbine is still quite high, which takes away a lot of heat. In general, the air temperature at the outlet of the compressor is much lower than the exhaust temperature of the turbine. Let the turbine exhaust pass through the regenerator to heat the air at the outlet of the compressor first, and then the air enters the combustion chamber, so that the heat added to the combustion chamber can be saved while the initial temperature of the gas remains unchanged, thereby improving the cycle efficiency.

2) Steam injection cycle: The steam generated by the waste heat boiler after the gas turbine is reinjected into the combustion chamber of the gas turbine, mixed with the gas, and expanded to perform work. Compared with the combined cycle, the efficiency of the steam injection cycle is slightly lower, and the specific power is higher; the pollutant discharge is reduced; the system structure is simple, and the cost is reduced; it can realize combined heat and power, and the heat and power adjustment range is large; Maintenance; good partial load performance, strong ability to quickly track the load; small footprint.

3) Forward and reverse coupling cycle: the pressure of the flue gas discharged from the gas turbine turbine is deliberately set below atmospheric pressure, followed by a gas turbine cycle with an isobaric cooling process of the flue gas and a compression process. For this cycle, the power consumption of recompressing flue gas from below atmospheric pressure to atmospheric pressure is much less than the expansion work of flue gas expanding from atmospheric pressure to below atmospheric pressure in the turbine; due to the existence of reverse cycle, the optimal pressure ratio of the cycle decreases; due to pressure As the ratio decreases, the compression work of the fuel decreases. Under the same conditions, the efficiency of the forward and reverse coupling cycle is about 1 to 2 percentage points higher than that of the simple forward cycle, and it is especially effective for cycles with high steam content in the flue gas, such as water injection cycles and steam injection cycles. At the same time, the condensed water can be recycled;

4) External-combustion gas turbine cycle: The high-temperature flue gas produced by the combustion of biomass, coal and other solid fuels in the boiler indirectly heats the air entering the combustion chamber of the gas turbine, which can completely or partially replace the clean fuel that needs to be added in the combustion chamber of the gas turbine, thereby Realize the efficient utilization of solid fuels such as biomass and coal.

The invention organically integrates technologies such as a gas turbine and its cycle, heat recovery, steam injection, forward and reverse cycle coupling, external combustion, etc., forming a new cycle that can greatly improve the energy utilization efficiency of biomass fuel. The equivalent power generation efficiency of biomass in this cycle is greatly improved compared with general biomass gasification power generation, direct combustion power generation, external combustion gas turbine power generation and other technical solutions. In addition, since the air required for biomass fuel combustion does not depend on gas turbine exhaust, the ratio of biomass fuel to clean fuel can be varied within a wide range during system design to cope with different fuel supply conditions. Biomass combustion external combustion gas turbine cycle is more flexible.

The dual-fuel steam injection forward and reverse gas turbine combined cycle of the present invention shows that under ISO conditions, when the compressor pressure ratio is 16, the outlet temperature of the combustion chamber is 1260°C, the cooling air volume is 18.65% of the total flow rate of the compressor, and the steam The pressure is 3.92Mpa, the turbine expands to 50kPa, the heat exchange efficiency of the regenerator and boiler gas-gas heater is taken as 0.9, the temperature difference between the superheater of the waste heat boiler and the inlet flue gas is 60°C, and the flue gas enters The exhaust compressor is cooled to 27°C, the heat exchange efficiency of the boiler air preheater is taken as 0.8, the isentropic adiabatic efficiency of the compressor is taken as 0.88, the isentropic adiabatic efficiency of the turbine is taken as 0.9, and the outlet temperature of the boiler flue gas is taken as Under the condition of 850 ℃, when the fuel energy ratio of biomass fuel and clean fuel is 0.7, the power generation efficiency of the whole cycle system reaches 44.26%. If the steam injection cycle efficiency under the same conditions is assumed to be 47.78%, the biomass The converted power generation efficiency is 39.21%. If it is assumed that the efficiency of the conventional biomass gasification and combustion power generation system is 32%, the power generation efficiency of biomass fuel will increase by 7.21%. Other conditions remain unchanged, when the fuel energy ratio of biomass fuel and clean fuel is 0.52, 0.35, 0.21, 0.10, the power generation efficiency of the entire cycle system reaches 45.54%, 47.53%, 48.54%, 49.60%, and the equivalent power generation of biomass The efficiency reaches 44.17%, 46.82%, 52.12%, and 68.32%, which is 12.17%, 14.81%, 20.12%, and 36.32% higher than that of conventional biomass power generation systems. The extent of improvement in power generation efficiency varies with gas turbines and biomass combustion conditions, but the applicability of the present invention is not limited by the model, capacity, and type of biomass of the gas turbine.

The embodiments of the present invention are not limited thereto. According to the above content of the present invention, using ordinary technical knowledge and conventional means in this field, without departing from the above-mentioned basic technical ideas of the present invention, the present invention can also make other various forms. Amendment, replacement or alteration all fall within the protection scope of the present invention.

Claims (10)

1. a double fuel steam injection forward and reverse Gas Turbine Combined-cycle, wherein:

Air is entered by the air input of compressor；

The outfan of compressor inputs with the air input of combustion gas regenerator and the cooling air of turbine End is connected；

The flue gas outfan of combustor is connected with the flue gas input of turbine；

The flue gas outfan of turbine is connected with the flue gas input of combustion gas regenerator；

Enter by the fuel inlet port of boiler for adding the biomass fuel of hot-air；

It is characterized in that:

The outfan of compressor is connected with the cooling air input of turbine；

The air outfan of combustion gas regenerator is connected with the air input of boiler gas-to-gas heat exchanger；

The air outfan of boiler gas-to-gas heat exchanger is connected with the air input of combustor, is used for heating The cleaning fuel of air is entered by the fuel inlet port of combustor；

The flue gas outfan of combustion gas regenerator is connected with the flue gas input of superheater；

The flue gas outfan of superheater is connected with the flue gas input of vaporizer；

The flue gas outfan of vaporizer is connected with the flue gas input of economizer；

The flue gas outfan of economizer is connected with the heat smoke input of flue gas recuperator；

Condensed water is derived from flue gas recuperator；

The heat smoke outfan of flue gas recuperator is connected with the flue gas input of gas cooler, condensed water Derive from gas cooler；

The flue gas outfan of gas cooler is connected with the flue gas input of scavenging compressor；

The flue gas outfan of scavenging compressor is connected with the cold flue gas input of flue gas recuperator, heated Cold flue gas discharge emptying from the cold flue gas outlet side of flue gas recuperator；

Waste heat boiler feedwater is entered by the water input of economizer, and waste heat boiler is overheated by be sequentially connected Device, vaporizer, economizer form；

The water outfan of economizer is connected with the water input of vaporizer；

The saturated vapor outfan of vaporizer enters the saturated vapor outfan of superheater and is connected；

The superheated steam outfan of superheater is connected with the superheated steam input of combustor；

The flue gas outfan of boiler is connected with the flue gas input of boiler gas-to-gas heat exchanger；

The flue gas outfan of boiler gas-to-gas heat exchanger is connected with the flue gas input of boiler air preheater, The flue gas emptying exported by the flue gas outfan of boiler air preheater；

Air needed for boiler combustion is entered by the air input of boiler air preheater；

The air outfan of boiler air preheater is connected with the air input of boiler；

Complementary work after the expansion work deduction compressor of turbine and the work done during compression of scavenging compressor promotes to be sent out Motor rotation.

Double fuel steam injection forward and reverse Gas Turbine Combined-cycle the most according to claim 1, its In, the flue gas subatmospheric power of turbine outlet.

Double fuel steam injection forward and reverse Gas Turbine Combined-cycle the most according to claim 2, its In, turbine exiting flue gas pressure is 0.1～0.95bar.

Double fuel steam injection forward and reverse Gas Turbine Combined-cycle the most according to claim 1, its In, flue gas recuperator, gas cooler are equipped with condensate water recovery device, and the condensed water of recovery is through place The feedwater of waste heat boiler is can be used as after reason.

Double fuel steam injection forward and reverse Gas Turbine Combined-cycle the most according to claim 1, its In, gas cooler is provided with cooling water cooler, and the water input of cooling water cooler cools down with flue gas The water outfan of device connects, and the water outfan of cooling water cooler is by the water of water pump with gas cooler Input connects.

Double fuel steam injection forward and reverse Gas Turbine Combined-cycle the most according to claim 1, its In, it is provided with water droplet mistake between flue gas outfan and the flue gas input of scavenging compressor of gas cooler Filter, the flue gas outfan of gas cooler is by defeated with the flue gas of scavenging compressor after water droplet filter Enter end to be connected.

Double fuel steam injection forward and reverse Gas Turbine Combined-cycle the most according to claim 1, its In, the superheated steam produced from superheater introduces combustor, for external heat supply.

Double fuel steam injection forward and reverse Gas Turbine Combined-cycle the most according to claim 1, its In, boiler refer to fuel and air adiabatic combustion wherein and the fluid bed the most not arranging water-cooling wall or CFBB, the fire box temperature of boiler is 650-850 DEG C.

Double fuel steam injection forward and reverse Gas Turbine Combined-cycle the most according to claim 8, its In, fluid bed or CFBB are added with desulfurizing agent.

Double fuel steam injection forward and reverse Gas Turbine Combined-cycle the most according to claim 1, its In, cleaning fuel includes natural gas, synthesis gas, liquefied petroleum gas, all kinds of distilled oil, methanol, second One or more in alcohol.