A method for achieving zero emissions in cement thermoelectric co - generation and producing chemical products

Abstract

The present invention discloses a method for realizing zero emissions in cement cogeneration and chemical product production, which combines gas-supercritical carbon dioxide cycle power generation with building material firing. The temperature in the combustion chamber is controlled by circulating CO2. The high-temperature and high-pressure flue gas generated in the combustion chamber enters the turbine generator for power generation. The CO2 waste heat coming out of the recuperator can be used to heat hot water to provide a hot water load. The CO2 coming out of the cooler / heat exchanger enters the CO2 compressor to continue the cycle. By burning pure oxygen natural gas, the present invention can greatly improve the system thermal efficiency. Or through the electric firing technology, there is no NOx production during the process, and there is only CO2 and water in the flue gas, greatly reducing the CO2 capture cost. The CO2 is used to produce chemical products, realizing zero emissions of CO2 and harmful pollutants in the system.

Description

Technical Field

[0001] The present invention belongs to the technical fields of cogeneration of heat and power, building materials, hydrogen energy, and chemical material production, and particularly relates to a method for realizing zero emissions in the cogeneration of cement heat and power and the production of chemical products. Background Art

[0002] The thermal efficiency of traditional gas-supercritical carbon dioxide combined cycle power generation is about 40-60%, and there is little room for further improvement in heat utilization efficiency.

[0003] The traditional method of making building materials products is to provide heat by burning pulverized coal or other fuels (such as garbage, biomass, etc.) to fire the raw materials. After fuel combustion, a large amount of CO 2 emissions will be caused, and the low concentration of CO in the exhaust gas leads to high capture costs. It will also produce a large amount of harmful substance emissions such as NOx, SO2, and dust. 2 Summary of the Invention

[0004] In order to overcome the above technical problems, the purpose of the present invention is to provide a method for realizing zero emissions in the cogeneration of cement heat and power and the production of chemical products. By burning pure oxygen natural gas, the system thermal efficiency can be greatly improved, or through the electric firing technology, no NOx is produced during the process, and there is only CO 2 and water in the flue gas, greatly reducing the CO 2 capture cost. The CO 2 is used to produce chemical products, realizing zero emissions of CO 2 and harmful pollutants in the system.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0006] A method for realizing zero emissions in the cogeneration of cement heat and power and the production of chemical products, comprising the following steps;

[0007] S1: Set a gas turbine, burn gas and pure oxygen in the combustion chamber of the gas turbine, control the temperature in the combustion chamber through circulating CO 2 The high-temperature and high-pressure flue gas generated in the combustion chamber enters the turbine generator to generate electricity;

[0008] S2: Part of the exhaust gas of the gas turbine in S1 enters the building materials kiln for raw material decomposition. When the heat and temperature are insufficient, it is provided by the natural gas pure oxygen combustion nozzle and the electric power CO 2 plasma nozzle. The building materials kiln completes the decomposition and calcination of the materials; another part of the flue gas enters the CO 2 waste heat boiler as the heat source for supercritical CO 2 cycle power generation; The exhaust gas volume entering the building materials kiln and the CO 2 waste heat boiler is distributed according to the principle of heat-determined power;

[0009] S3: The flue gas coming out from the upper part of the building materials kiln in S2 enters the steam waste heat boiler to generate steam, continues to recover heat, the generated steam enters the steam turbine for power generation, the flue gas coming out from the upper part of the building materials kiln continues to be used as the heat source for the raw material mill, and finally enters the CO 2 capture device;

[0010] S4: A part of the flue gas coming out from the gas turbine is used as the heat source for the supercritical cycle power generation of CO 2 , then enters the steam waste heat boiler to generate steam. After the steam enters the steam turbine for power generation, it continues to be used as the heat source for the raw material mill drying, and then enters the CO 2 capture device;

[0011] S5: After being heated by the flue gas, the supercritical CO in S4 2 enters the supercritical CO 2 turbine for power generation. After power generation, the CO 2 enters the regenerator to reheat the CO coming out from the CO 2 compressor; The waste heat coming out from the regenerator can heat the hot water to provide the hot water load; The CO coming out from the cooler / heat exchanger 2 enters the CO 2 compressor to continue to complete the cycle; 2 2 2 2

[0012] S6: The CO generated by the CO 2 capture device in S4 2 is used in the device for synthesizing chemical products to synthesize chemical products by using hydrogen and CO 2 ;

[0013] S7: Set up an electrolytic water or other hydrogen and oxygen production device to produce hydrogen and oxygen. The oxygen is supplied to the combustion chamber for use, and the hydrogen is used as the raw material for the chemical synthesis device;

[0014] S8: The water for the electrolytic water or other hydrogen and oxygen production device is supplied by the water generated by the combustion of natural gas and the water produced by the chemical synthesis device.

[0015] The temperature in the combustion chamber in the said S1 is controlled at 1100 - 1700 °C.

[0016] The control pressure of the said gas turbine is 1.2 - 4.0 MPa.

[0017] The temperature in the decomposition section of the building materials kiln in the said S2 is controlled at 500 - 900 °C, and the temperature in the calcination section is controlled at 900 - 1300 °C.

[0018] The principle of heat - based power generation in the said S2 is specifically to determine the total heat supply of the flue gas according to the sum of the heat loads of the building materials kiln and the hot water heat load, so as to determine the power generation amount of the gas turbine.

[0019] The CO in S5 2 The CO coming out of the compressor 2 The temperature for reheating is 180 - 450 °C, and the waste heat of CO 2 is below 180 °C.

[0020] Advantages of the present invention:

[0021] (1) Combining traditional gas - supercritical carbon dioxide cycle power generation with building material firing can greatly improve the system thermal efficiency, and the comprehensive energy efficiency of the system can reach more than 90%;

[0022] (2) Making full use of the exhaust waste heat of the gas turbine to preheat, decompose and fire in the building material production process, reducing the fuel consumption of the building material kiln;

[0023] (3) Through pure - oxygen natural gas combustion or electric firing technology, no NOx is produced during the process, and there is only CO 2 and water in the flue gas, without the emission of harmful pollutants;

[0024] (4) Only CO 2 and water are produced in the whole system, greatly reducing the CO 2 capture cost. Capturing through the production of chemical products from CO 2 realizes zero emission of CO 2 ;

[0025] (5) Gas - supercritical carbon dioxide cycle power generation can perform peak shaving for new - energy power generation to ensure the consumption of green electricity;

[0026] (6) In the non - heating season when natural gas supply is relatively sufficient, increasing the processing load of the building material factory can expand the use of natural gas; in the heating season, reducing the processing load of the building material factory can reduce the use of natural gas; therefore, this system can well perform peak shaving for natural gas. Brief Description of the Drawings

[0027] Figure 1 It is a schematic flow diagram of the present invention. Detailed Embodiment

[0028] The present invention will be further described in detail below with reference to the drawings.

[0029] As Figure 1 shown: A method for cement cogeneration and production of chemical products to achieve zero emission, including the following steps;

[0030] S1: Set up a gas turbine, burn gas and pure oxygen in the combustion chamber, control the temperature in the combustion chamber through circulating CO 2 The high - temperature and high - pressure flue gas generated in the combustion chamber enters the turbine generator to generate electricity;

[0031] S2: Part of the exhaust gas of the gas turbine enters the building materials kiln for raw material decomposition. When the heat and temperature are insufficient, it is provided by the natural gas pure oxygen combustion nozzle and the electric CO 2 plasma nozzle. The building materials kiln completes the decomposition and calcination of the materials; the other part of the flue gas enters the CO 2 waste heat boiler as the heat source for supercritical CO 2 cycle power generation; The exhaust gas volume entering the building materials kiln and the CO 2 waste heat boiler is distributed according to the principle of heat-determined power generation;

[0032] S3: The flue gas coming out from the upper part of the building materials kiln enters the steam waste heat boiler to generate steam, continuously recover heat, and the generated steam enters the steam turbine for power generation. The flue gas coming out from the upper part of the building materials kiln continues to be used as the heat source for the raw material mill and finally enters the CO 2 capture device;

[0033] S4: Part of the flue gas coming out from the gas turbine is used as the heat for supercritical CO 2 cycle power generation, then enters the steam waste heat boiler to generate steam. After the steam enters the steam turbine for power generation, it continues to be used as the heat source for raw material mill drying, and then enters the CO 2 capture device;

[0034] S5: The supercritical CO 2 in S4 is heated by the flue gas and then enters the supercritical CO 2 turbine for power generation. After power generation, the CO 2 enters the regenerator to reheat the CO 2 coming out from the CO 2 compressor; The waste heat coming out from the regenerator can heat the hot water to provide the hot water load; The CO 2 coming out from the cooler / heat exchanger enters the CO 2 compressor to continue to complete the cycle; 2

[0035] S6: The CO 2 produced by the CO 2 capture device in S4 is synthesized to produce chemical products, and hydrogen and CO 2 are used to synthesize chemical products;

[0036] S7: Set up electrolytic water or other hydrogen and oxygen production devices to produce hydrogen and oxygen. The oxygen is supplied to the combustion chamber for use, and the hydrogen is used as the raw material for the chemical synthesis device;

[0037] S8: The water for the electrolytic water or other hydrogen and oxygen production devices is supplied by the water generated by natural gas combustion and the water produced by the chemical synthesis device.

[0038] ​In S1, the temperature in the combustion chamber is controlled at 1100 - 1700 °C. According to the temperature tolerance of the selected turbine material, the temperature of the combustion chamber should be increased as much as possible without exceeding the maximum temperature limit of the turbine.

[0039] The control pressure of the gas turbine is 1.2 - 4.0 MPa. According to the temperature tolerance of the selected turbine material, the pressure of the combustion chamber should be increased as much as possible without exceeding the maximum pressure limit of the turbine.

[0040] In S2, the temperature of the decomposition section of the building materials kiln is controlled at 500 - 900 °C, and the temperature of the calcination section is controlled at 900 - 1300 °C to fully preheat, decompose, and calcine the raw materials.

[0041] The principle of heat - to - power in S2 is specifically to determine the total heat supply of the flue gas according to the sum of the heat loads of the building materials kiln and the hot water heat load, and then determine the power generation of the gas turbine.

[0042] CO in S5 2 CO from the compressor 2 The temperature for reheating is 180 - 450 °C, recovering the exhaust waste heat of the CO turbine, and reducing the heat demand for high - temperature flue gas. CO 2 The waste heat is below 180 °C. 2

[0043] In the present invention, the gas - CO 2 The supercritical power generation system can also regulate the power generation peak of surrounding new energy, ensure the consumption of green electricity, and can also be used as the power source for building materials factories and chemical plants, while also taking into account natural gas peak regulation.

[0044] The natural gas pure - oxygen burner burns natural gas and pure oxygen, and uses CO 2 as a heat carrier to control the temperature after combustion.

[0045] Electric firing uses CO 2 as a heat carrier, which has the advantages of fast heat and mass transfer speed, controllable temperature, etc. It is a pure physical heating process, without unburned substances and no pollution.​

Claims

1. A method for achieving zero emissions in cement cogeneration of heat and power and producing chemical products, characterized in that, it includes the following steps; S1: Set up a gas turbine. The gas and pure oxygen burn in the combustion chamber, and the temperature in the combustion chamber is controlled by circulating CO. 2 The high-temperature and high-pressure flue gas generated in the combustion chamber enters the turbine generator to generate electricity. S2: Part of the flue gas from the gas turbine in S1 enters the building materials kiln for raw material decomposition. When the heat and temperature are insufficient, it is provided by the natural gas pure oxygen combustion nozzle and the electric CO 2 plasma nozzle. The building materials kiln completes the decomposition and calcination of the materials; Another part of the flue gas enters the CO 2 waste heat boiler as the heat source for supercritical CO 2 circulation power generation; The principle of heat-based power generation is adopted to allocate the flue gas volume entering the building materials kiln and the CO 2 waste heat boiler; S3: The flue gas coming out from the upper part of the building materials kiln in S2 enters the steam waste heat boiler to generate steam, continues to recover heat, the generated steam enters the steam turbine for power generation, the flue gas coming out from the upper part of the building materials kiln continues to be used as the heat source for the raw material mill, and finally enters the CO 2 capture device; S4: A part of the flue gas coming out of the gas turbine is used as CO 2 After the heat of the supercritical cycle power generation, it enters the steam waste heat boiler to generate steam. After the steam enters the steam turbine for power generation, it continues to be used as the heat source for the mill drying, and then enters the CO 2 Capture device; S5: Supercritical CO in S4 2 After being heated by flue gas, it enters supercritical CO 2 for power generation in a turbine. After power generation, the CO 2 enters a recuperator to reheat the CO 2 coming out of the CO compressor 2 ; The CO coming out of the recuperator 2 uses its waste heat to heat hot water to provide a hot water load; The CO coming out of the cooler / heat exchanger 2 enters the CO 2 compressor to continue the cycle; S6: Feed the CO 2 produced by the CO capture device 2 to synthesize chemical products by using hydrogen and CO 2 to synthesize chemical products; S7: Set up electrolytic water or other hydrogen and oxygen production devices to produce hydrogen and oxygen. The oxygen is supplied to the combustion chamber for use, and the hydrogen is used as the raw material for the synthetic chemical device; S8: The water for the electrolytic water or other hydrogen and oxygen production devices is supplied by the water generated from natural gas combustion and the water produced by the chemical synthesis device.

2. The method for achieving zero emissions in cement cogeneration of heat and power and producing chemical products according to claim 1, characterized in that, the temperature in the combustion chamber in S1 is controlled at 1100 - 1700 °C.

3. The method for achieving zero emissions in cement cogeneration of heat and power and producing chemical products according to claim 1, characterized in that, the control pressure of the gas turbine is 1.2 - 4.0 MPa.

4. The method for achieving zero emissions in cement cogeneration of heat and power and producing chemical products according to claim 1, characterized in that, the temperature in the decomposition section of the building materials kiln in S2 is controlled at 500 - 900 °C, and the temperature in the calcination section is controlled at 900 - 1300 °C.

5. The method for achieving zero emissions in cement cogeneration of heat and power and producing chemical products according to claim 1, characterized in that, the principle of heat - based power determination in S2 is specifically to determine the total heat supply of the flue gas according to the sum of the heat loads of the building materials kiln and the hot water heat load, so as to determine the power generation of the gas turbine.

6. The method for achieving zero emissions in cement cogeneration of heat and power and producing chemical products according to claim 1, characterized in that, The CO in S5 2 The CO from the compressor 2 The temperature for reheating is 180 - 450 °C, and the CO 2 The waste heat temperature is below 180 °C.

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