Low-carbon coal-based poly-generation LNG energy storage NGCC power generation peak regulation method

Abstract

The invention discloses a low-carbon coal-based poly-generation LNG energy storage NGCC power generation peak regulation method. At present, coal-to-oil, natural gas and methanol all cause a large amount of carbon emission due to oxygen fire coal heat supply; the cost of various stored energy in medium and long time periods is increased sharply. The pressurized moving bed is used for directly producing methane through coal hydrogenation and low carbon emission, and meanwhile coal tar is produced through zero carbon emission heat release, raw coal pyrolysis and near zero emission; green hydrogen produced by wind-solar-electricity is used for coal tar hydrogenation to produce fuel oil, so that near-zero emission of coal-based fuel oil production can be realized. Methane is separated from hydrogen gas in an LNG state by using wind, light and electricity as cryogenic power, the purpose of storing the wind, light and electricity at low cost for a long time by taking the LNG as a cold energy carrier is achieved, when the LNG needs to pass through NGCC power generation peak regulation, cold energy is exchanged to a to-be-liquefied material system through a cold box for liquefying methane and oxygen after the LNG is pressurized, and the LNG is converted into SNG to become fuel for NGCC power generation peak regulation.

Description

Technical Field

[0001] The present invention belongs to the field of coal-based energy chemical engineering, and particularly relates to process technologies and equipment for using green wind and solar energy to produce low-carbon and low-cost coal-based fuel, SNG, methanol, LNG energy storage, and NGCC natural gas steam combined cycle power generation peak shaving. Background Art

[0002] The installed capacity of the wind and solar power industry in China has exceeded that of coal-fired power. However, due to the intermittency, volatility, and randomness of wind and solar energy, the grid connection and consumption are very limited. Most of it needs to be locally consumed, or short-distance transported and converted for utilization, or stored for a short time before consumption.

[0003] Directly using chemical batteries for wind and solar power energy storage has many restrictive factors such as the manufacturing cost, aging, energy storage efficiency, energy density, waste recycling, and key material resources of chemical batteries. Especially in the large-scale application of chemical battery energy storage in the power and energy chemical industries in the three northern regions of China, the market is still far away due to the difficulty of significantly reducing costs.

[0004] Using physical methods such as compressed air, pumped water, and gravity for wind and solar power energy storage, due to the too low energy density on the energy-carrying medium and related special conditions, it is difficult to significantly reduce the energy storage cost in the next few decades that can be foreseen.

[0005] For medium- and long-term energy storage of wind and solar power, whether it is electrochemical energy storage or energy storage based on mechanical principles such as compressed air, pumped water, and gravity, the cost will increase sharply in the face of continuous windless and cloudy days for more than 150 hours in a large area.

[0006] For liquefied natural gas energy storage, especially in the storage cycle of 360 - 500 hours, the energy storage cost per kWh is as low as one-tenth of various existing physical and chemical energy storage methods. Obviously, advanced and low-carbon coal-based LNG production technologies should be developed. Using wind and solar power for short-term energy storage of less than 30 hours has acceptable economy. While converting the advantageous resource of coal in the three northern regions into LNG, the local consumption and utilization of the advantageous resource of wind and solar power can be realized. Then, using the low-cost long-term energy storage advantage of LNG, while storing LNG at low cost, medium- and long-term low-cost energy storage of 360 - 500 hours for wind and solar power can be achieved.

[0007] For a large number of coal-fired thermal power plants in China, even if only 50% of CO 2 is captured from their flue gas, not only will the coal consumption for power supply far exceed 300 g / kWh and the power supply cost increase significantly, but there is also a problem of the disposal destination of the captured CO 2 . Obviously, the current technical solution of directly capturing CO 2 from the flue gas of coal-fired power plants to reduce the CO 2 emission per kWh is not easily accepted by all parties in society.

[0008] In current integrated gasification combined cycle (IGCC) power generation, due to the coal gasification process with high investment, high oxygen consumption, and low energy efficiency, not only can the high-efficiency gas turbines not compensate for its defects, but also the load regulation advantage of gas turbine power generation is completely lost. If carbon elements in the gas are captured, a CO shift process with a chemical heat loss of 15% needs to be set up to convert CO in the coal gas into CO 2 before it can be captured. This not only requires high investment but also causes the energy conversion efficiency of IGCC to decrease by at least 4 percentage points. Obviously, using this method to reduce the CO emissions per kWh is not easily acceptable to society; 2

[0009] China's resource endowment of rich coal, scarce oil, and little gas has led to a large amount of imports of crude oil and natural gas. High-carbon coal-based power, coal-to-oil, coal-to-natural gas, coal-to-methanol and other chemical industries emit a large amount of carbon dioxide when providing products to society, seriously restricting China's carbon emission reduction process. One of the main reasons is that the energy consumption in its process is too high. For example, in the national standard GB30180-2024 to be implemented on May 1, 2025, the energy consumption of the coal-to-natural gas process is as high as 1.1 kgce / m 3 . The energy consumption of the indirect liquefaction coal-to-oil process reaches 2 tce / t of oil. If wind and solar power are used to replace the high energy consumption of coal-to-natural gas and fuel oil, its carbon emissions will be greatly reduced, but the already high cost of its products will double. Obviously, without improving the current production processes of coal-to-natural gas, fuel oil, and coal chemical industries and significantly reducing the process energy consumption, it will be very difficult to use wind and solar power to significantly reduce the carbon emissions of current coal-based energy and chemical industries.

[0010] CN112126469B discloses a method for IGCC combined cycle power generation with co-production of fuel oil and natural gas, which can significantly reduce the process energy consumption. However, since the residual coke in the isolation section enters the water gas section and flows automatically by gravity without a control device, it is easy to cause gas leakage between the hydrogen gas section and the water gas section, and there may also be blockage and non-unloading of residual coke in the hydrogen gas section. Hydrogen is all added from the cylinder, making it impossible to achieve the best control of the distribution of hydrogen entering the central area of the cross-section, and its process cannot consume a large amount of wind and solar power.

[0011] CN115483688A, a method for power grid peak shaving of coal-to-oil and gas power generation, proposes to establish a local power grid of wind, solar, coal, and gas with wind energy + photovoltaic + solar thermal power generation + coal-to-oil / natural gas + gas non-aqueous working medium combined cycle power generation to achieve power grid peak shaving. The cost of the non-aqueous working medium combined cycle is still difficult to be significantly reduced in the foreseeable future. The output of methanol produced by entrained flow coal gasification reached 67.425 million tons in 2023, and its CO emissions 2 ​As much as 240 million tons. Obviously, in the low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving process using wind and solar power, a new process for co-producing low-carbon coal-based methanol should also be developed to reduce the CO emissions of coal-to-methanol. 2 emissions. Summary of the Invention

[0012] The object of the present invention is to adopt a pressurized moving bed with controllable residual coke downward movement amount, directly produce methane, coal tar, and water gas from coal hydrogenation while consuming wind and solar power, and achieve coal-based LNG, methanol, fuel polygeneration + LNG energy storage + NGCC power generation peak shaving with low carbon and low cost.

[0013] The specific invention content is as follows:

[0014] 1. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method, which consists of an oxygen and steam gasifying agent inlet, a grate, a raw material gasification bed layer, a stirrer, a coal distributor, and a coal lock, a pressure-bearing water jacket shell, and a raw gas outlet. Among them, the raw material gasification bed layer is divided into an ash layer, an oxygen combustion layer, a water gas generation layer, a methane generation layer, and a raw coal drying layer from bottom to top. Oxygen and steam react with raw coal from bottom to top to generate water gas. Its characteristics are:

[0015] The pressurized moving bed gasifier is designed as a pressurized moving bed gasifier with an upper hydrogen gas section and a lower water gas section, which is connected by a circumferential drive screw discharger (14), a residual coke isolation zone (13), and a pressure-bearing cylinder body (14A) of the residual coke downward movement channel inside it. See the appendix; by controlling the rotation speed of the circumferential drive screw discharger (14), the rate of residual coke in the hydrogen gas section entering the water gas section is adjusted, and then the production load of the entire pressurized moving bed gasifier and the gasification ratio of raw coal in the upper and lower sections are controlled in cooperation with the addition amount of raw coal (4) and hydrogen gasifying agent (3) in the hydrogen gas section, and the rotation speed of the grate (18A) and the addition amount of oxygen-enriched steam (1) in the water gas section; at the same time, the isolation effect of the spiral blades of its screw discharger is used to reduce or eliminate the gas leakage between the water gas section and the hydrogen gas section; Figure 2 The lower section of the pressurized moving bed gasifier is designed to use an oxygen-enriched steam gasifying agent composed of oxygen and steam, take the residual coke from the hydrogen gas section as raw material, and produce a water gas section mainly composed of hydrogen and carbon monoxide through the reactions of C + O

[0016] = CO 2 = CO 2 and C + H 2 O = CO + H 2 reaction; the source of oxygen is the oxygen by-product of the electrolytic water hydrogen production device (1D), or the oxygen produced by the air separation oxygen production workshop (1C), or both provided together;

[0017] The upper section of the pressurized moving-bed gasifier is designed to use a hydrogen gasifying agent (3) with methane ≤ 3%, hydrogen ≥ 80%, CO + CO 2 +N 2 ≤ 3%, H 2 S ≤ 0.1%, steam ≤ 15%. Using briquettes made from crushed coal or pulverized coal with a particle size of 3 - 80 mm as raw materials, through the chemical reaction C + 2H 2 = CH 4 to directly produce the main product methane. At the same time, using the gas-solid countercurrent process, the chemical reaction heat of C + 2H 2 = CH 4 is utilized. For every 1 Nm 3 of methane produced, there is about 800 kcal of zero-carbon emission heat release, which is directly used for pyrolyzing and dry distilling the raw coal to produce the secondary product coal tar, that is, using its zero-carbon emission heat release to pyrolyze the raw coal and produce coal tar with nearly zero-carbon emission. That is, the upper section of the pressurized moving-bed gasifier is designed as a hydrogen gas section for producing hydrocarbon-rich hydrogen gas of methane and coal tar through coal hydrogenation gasification. By controlling the addition amount of steam in hydrogen, the appropriate and endothermic water gas reaction C + 2H 2 O = CO + H 2 directly absorbs the heat released by the coal hydrogenation reaction C + 2H 2 = CH 4 . Thus, it not only avoids the over-temperature coking of the gasification bed layer in the hydrogenation gas section but also effectively controls the adverse impact of the excessive increase in the bed layer temperature on improving the methane concentration. It also supplements hydrogen raw materials for more coal hydrogenation reactions C + 2H 2 = CH 4 .

[0018] The water gas (21) coming from the water gas section and exiting through the water gas outlet (2) is heat recovered by the dust removal waste heat boiler (22) and purified by the fine dust removal and desalination device (24). When it is necessary to consume wind and solar power, part of the water gas (25A) does not need to go through the CO shift process to increase the H 2 / CO molar ratio and is directly sent to the methanol synthesis unit (25B). The synthesis of methanol requires H 2The increased amount of hydrogen with a molar ratio of H₂ / CO reaching 2 - 2.1 is provided by the hydrogen produced from the wind-solar power electrolytic water hydrogen production / oxygen production device (1D). The synthesized methanol is sent into the methanol storage tank (25D) through the pipeline (25C). When there is no need to consume wind-solar power, the electrolytic water hydrogen production / oxygen production device (1D) and the methanol synthesis device (25B) can choose to operate at low load for heat preservation or stop according to the length of time. All of its water gas (21) is sent into the CO conversion device (26) to convert 97% of the CO into hydrogen, and then sent into the NHD desulfurization PSA decarbonization device (28) for desulfurization and decarbonization. The separated hydrogen is sent into the inlet hydrogen main pipe (36) of the hydrogen circulation machine (37) as the supplementary hydrogen (28A) consumed in the direct coal hydrogenation to produce methane, and is used for the direct coal hydrogenation to synthesize methane.

[0019] The rich hydrocarbon hydrogen gas (31) coming out from the rich hydrocarbon hydrogen gas outlet (3D) of the hydrogen gas section undergoes dust removal, heat recovery, cooling, separation of coal tar and water, CO conversion, separation and purification of acid gases such as hydrogen sulfide and CO 2 through the acid gas separation and purification device (32) and becomes a pure methane-hydrogen gas (33) mixture, and then enters the hydrogen-methane liquefaction and separation device (34) for methane liquefaction and separation. The separated liquefied methane LNG is sent into the LNG storage tank (34D) for temporary storage to supply NGCC power generation for peak shaving or for sale. The refrigeration power electricity required for methane liquefaction separation and the power electricity required for the continuous operation of the entire coal-based polygeneration system are provided by wind-solar power when there is a need to consume wind-solar power, enabling wind-solar power to be converted into low-cost storage in the form of LNG through this process. When there is no wind-solar power, methane liquefaction and all power are provided by the self-produced methane or the recovered cold energy of the self-produced LNG through NCGCC power generation. When NGCC power generation peak shaving is required, the LNG stored in the LNG storage tank (34D) is pressurized and sent through the pipeline (34E) to the cold box of the hydrogen-methane liquefaction and separation device (34) or the air separation oxygen production (1C). After the cold energy of the LNG is exchanged with the methane or oxygen to be liquefied, it becomes normal temperature synthetic natural gas (SNG), and then is sent into the gas turbine (34A) of the NGCC combined cycle unit for power generation peak shaving. This not only recovers the cold energy stored in LNG, but also greatly reduces the power consumption demand for methane-hydrogen gas (33) liquefaction separation and air separation oxygen production (1C) refrigeration when the power grid needs power generation peak shaving. Here, there are multiple sets of NGCC power generation peak shaving units. When there is no need for power generation peak shaving, only one set of NGCC power generation needs to be started to supply the power required for the system of this case. When there is a need to consume wind-solar power, the NGCC power generation unit can operate at low load or stop, enabling the system energy consumption to consume wind-solar power as much as possible and reducing the carbon emissions of the coal-based polygeneration.

[0020] The crude coal tar (32E) separated from the separation and purification device (32) is first sent to the coal tar storage device (32H) for temporary storage or buffering; when it is necessary to absorb wind and photovoltaic power, it is then sent to, or the load is increased and sent to, the coal tar to fuel device (4D), and together with the hydrogen (34C) produced by the electrolyzed water to hydrogen and oxygen device (ID) powered by wind and photovoltaic power, the fuel production is completed; since the heat source for producing coal tar comes from the exothermic reaction of direct hydrogenation of coal with zero carbon emissions to produce methane, and the storable characteristics of coal tar are utilized for temporary storage, and when it is necessary to absorb wind and photovoltaic power, hydrogen produced by wind and photovoltaic power is used to generate fuel, and almost no carbon emissions occur during the entire coal-based fuel production process. Therefore, using the coal-to-fuel method in this case will greatly reduce carbon emissions compared to the traditional one-step or two-step coal-to-oil methods, and even achieve near-zero emissions.

[0021] The hydrogen gas section is designed from bottom to top in sequence as follows:

[0022] The high-temperature coke hydrogenation gasification layer (12), and at its lower part, there are designed a high-temperature hydrogenation gasification layer hydrogen inlet (3A), an annular channel (12D), a high-temperature hydrogenation distributor (12A), a high-temperature hydrogenation central area inlet pipe (12C), and a high-temperature hydrogenation central area distributor (12B); the hydrogen from the hydrogen inlet (3A) enters the annular area except the central area of the high-temperature coke hydrogenation gasification layer (12) through the annular channel (12D) and the distributor (12A); the hydrogen from the central area inlet pipe (12C) enters the central area of the high-temperature coke hydrogenation gasification layer (12) through the central area distributor (12B), so as to achieve the uniform distribution of hydrogen in the high-temperature coke hydrogenation gasification layer (12);

[0023] The medium-temperature hydrogenation gasification layer (11), and at its lower part, there are provided a medium-temperature hydrogenation distributor (11A), a medium-temperature hydrogenation central area distributor (11B), a medium-temperature hydrogenation central area intake sleeve (11C), and a medium-temperature annular channel (11D); the hydrogen from the hydrogen inlet (3B) enters the annular area except the central area of the medium-temperature hydrogenation gasification layer (11) through the medium-temperature annular channel (11D) and the medium-temperature hydrogenation distributor (11A); the hydrogen from the medium-temperature hydrogenation central area intake sleeve (11C) enters the central area of the medium-temperature hydrogenation gasification layer (11) through the medium-temperature hydrogenation central area distributor (11B), so as to achieve the uniform distribution of hydrogen in the medium-temperature hydrogenation gasification layer (11);

[0024] A low-temperature hydrogenation gasification layer (10), and a low-temperature hydrogenation distributor (10A), a low-temperature hydrogenation central region distributor (10B), a low-temperature hydrogenation central region intake sleeve (10C), and a low-temperature annular channel (10D) are provided below it; hydrogen from the hydrogen inlet (3C) enters the annular region of the low-temperature hydrogenation gasification layer (10) except for the central region through the low-temperature annular channel (10D) and the low-temperature hydrogenation distributor (10A); hydrogen from the low-temperature hydrogenation central region intake sleeve (10C) enters the central region of the low-temperature hydrogenation gasification layer (10) through the low-temperature hydrogenation central region distributor (10B), realizing the uniform distribution of hydrogen in the low-temperature hydrogenation gasification layer (10);

[0025] The semicoke hydrogenation gasification layer (9) mainly performs the hydrogenation of solid unsaturated hydrocarbons: C X H Y +(2X - 0.5Y)H 2 =XCH 4 , the reaction to generate methane;

[0026] The hydro-pyrolysis and dry distillation layer (7), and a debonding rotary disk (8) is provided between the hydro-pyrolysis and dry distillation layer (7) and the semicoke hydrogenation gasification layer (9); the power to drive the debonding rotary disk (8) is provided by a driving device (8B) provided at the top of the gasifier, which drives its coaxial hollow transmission shaft (8A), so that the coal particles cannot bond into particles larger than 80 mm and enter the semicoke hydrogenation gasification layer (9);

[0027] The hydrogenation drying layer (6);

[0028] The coal distributor (5);

[0029] The height-to-diameter ratio of the gasification bed in the hydrogen gas section is 2.0 - 4;

[0030] During normal production:

[0031] ① 30 - 40% of the total amount of hydrogen gas (3) entering the furnace enters the lower circular cross-section of the high-temperature hydrogenation gasification layer (12) evenly through the bottom inlet (3A) of the hydrogen gas section, the annular channel (12D), the high-temperature hydrogenation distributor (12A), the high-temperature hydrogenation central region intake pipe (12C), and the high-temperature hydrogenation central region distributor (12B), and then flows upward in reverse heat exchange with the high-temperature coke flowing downward at about 1050 °C, heating the normal-temperature hydrogen gas to 900 - 950 °C, enabling the hydrogen gas to carry out the methanation exothermic reaction of C + 2H 2 →CH 4 with the active carbon element in the high-temperature coke. While increasing the gas-phase methane content, it also raises the hot spot temperature of the high-temperature coke hydrogenation gasification layer (12) to 1050 °C below the ash melting point of the coal, making the gas-phase methane concentration reach the range of 10 - 15% and flow upward;

[0032] ② The gas phase with a methane concentration of 10-15% ascends, and is mixed with the hydrogen imported from the hydrogen addition gasification layer at medium temperature (3B), passing through the medium-temperature annular channel (11D), the medium-temperature hydrogen addition distributor (11A), and through the medium-temperature hydrogen addition central region intake sleeve (11C) and the medium-temperature hydrogen addition central region distributor (11B), and is mixed with the low-temperature hydrogen accounting for 30-40% of the total hydrogen input into the furnace (3). The temperature drops to 850-900 °C and continues to ascend into the medium-temperature hydrogen addition gasification layer (11), enabling the hydrogen therein to react with the active carbon element in the medium-temperature hydrogen addition gasification layer (11) again for the methanation exothermic reaction of C+2H 2 →CH 4 While increasing the gas-phase methane content, it also raises the hot spot temperature of the medium-temperature hydrogen addition gasification layer (11) to 950-1000 °C, and makes the gas-phase methane concentration reach the range of 15-20% and continue to ascend;

[0033] ③ The gas phase with a methane concentration of 15-20% ascends, and is mixed with the hydrogen imported from the hydrogen addition gasification layer at low temperature (3C), passing through the low-temperature annular channel (10D), the low-temperature hydrogen addition distributor (10A), and through the low-temperature hydrogen addition central region intake sleeve (10C) and the low-temperature hydrogen addition central region distributor (10B), and is mixed with the low-temperature hydrogen accounting for 20-30% of the total hydrogen input into the furnace (3). The temperature drops to 800-850 °C and continues to ascend into the low-temperature hydrogen addition gasification layer (10), enabling the hydrogen therein to react with the active carbon element in the low-temperature hydrogen addition gasification layer (10) again for the methanation exothermic reaction of C+2H 2 →CH 4 While increasing the gas-phase methane content, it also raises the hot spot temperature of the low-temperature hydrogen addition gasification layer (10) to 900-950 °C below the ash melting point of the coal, and makes the gas-phase methane concentration reach the range of 20-25% and continue to ascend;

[0034] ④ The gas phase with a methane concentration of 20-25% ascends into the semi-coke gasification layer (9), and reacts with the solid unsaturated hydrocarbon C in the semi-coke that descends from the hydro-pyrolysis and dry distillation layer (7) to the semi-coke gasification layer (9) through the sticky-breaking rotary disk (8) X H Y to carry out:

[0035] C X H Y +(2X - 0.5Y)H 2 =XCH 4 , and the hydrogenation reaction generates methane, making the gas-phase methane concentration reach 40-45%, and making the hot spot temperature of the semi-coke gasification layer (9) reach 750-800 °C;

[0036] ⑤ The gas phase with a methane concentration of 40-45% continues to rise, passes through the viscosity-breaking rotating disk (8) and rises to the hydro-pyrolysis and dry distillation layer (7). While transferring heat to the bed layer, the coal particles with a temperature of about 300 °C from the drying layer (6) are gradually heated to 600 °C and thermally decomposed to release coal tar. The coal tar is then gasified by heat, and part of the coal tar is hydrogenated to tar vapor and enters the gas phase, while part of the coal tar is dry-distilled into solid unsaturated hydrocarbon C X H Y ; Due to the relatively high methane content in the gas phase, the partial pressure P CH4 of the relatively high methane will reduce the methane production from coal pyrolysis and relatively increase the yield of tar gas; the hydro-pyrolysis of coal and tar further reduces the hydrogen content in the gas phase and raises the methane concentration to 45-50%;

[0037] ⑥ The gas phase rich in methane and tar continues to rise and enters the drying layer (6). While transferring heat to the bed layer, the adsorbed water in the coal is gasified by heat and enters the gas phase, causing the coal particles to be heated and dried;

[0038] In the hydrogen-rich gas section, through the above technological processes ①-⑥, the production of hydrogen-rich hydrocarbon gas (31) with raw coal and hydrogen as raw materials, methane as the main product, and coal tar as the secondary product is realized, and it leaves the gasifier through the hydrogen-rich hydrocarbon gas outlet (3D);

[0039] During normal production: The oxygen-containing gasifier composed of a mixture of oxygen and steam enters the gasifier from the oxygen-rich steam inlet (1) at the lower part of the water gas section of the gasifier, passes through the grate (18A), and passes through the ash layer (18) from bottom to top, absorbing the heat carried by the ash and raising the temperature to about 600 °C and entering the oxygen combustion layer (17). The oxygen in the gasifier causes the residual carbon element in the residual coke to burn and gasify rapidly, generating CO 2 and releasing a large amount of heat, raising the temperature of the steam in the gasifier and the bed layer above 1000 °C and below the ash melting point; The high-temperature steam containing CO 2 rises from bottom to top, transfers heat to the residual coke in the water gas reaction layer (16) and reacts with the carbon element in the residual coke in an endothermic steam gasification reaction C + H 2 O = CO + H 2 , causing most of the carbon elements in the residual coke to react with 30-40% of the water molecules in the steam and be converted into CO and H 2 in the raw gas. The raw gas becomes wet and hot with a temperature of about 700 °C and enters the gas collection area (15) at the upper part of the water gas reaction layer (16), and then flows out of the water gas section of the gasifier through the water gas outlet (2). Thus, the water gas section completes the production of water gas;

[0040] In the water gas section and hydrogen gas section of the gas furnace, temperature measuring thermocouples are respectively arranged at a vertical interval of 250 mm to monitor the temperature; pressure detection points are arranged at the near-feed end of the residual coke isolation area (13) and the outlet end of the circumferential drive screw discharger (14) to accurately control the pressure difference between the upper and lower ends and reduce and eliminate the gas leakage between the hydrogen gas section and the water gas section.

[0041] 2. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method according to the present case, characterized in that the raw coal fed into the furnace is heated, dehydrated, dried, pyrolyzed, semi-coke hydrogenated and rapidly gasified, low-temperature hydrogenated gasified, medium-temperature hydrogenated gasified, and high-temperature hydrogenated gasified from top to bottom in the hydrogen gas section. According to different coal types, ash contents, and moisture contents, the total mass is reduced by 40-55%, and the carbon element is reduced by 30-50%, becoming residual coke; the inner cylinder of the hydrogen gas section furnace body is a frustum of a cone with a smaller upper part and a larger lower part.

[0042] 3. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method according to the present case, characterized in that when LNG power generation peak shaving is required, the LNG stored in the LNG storage tank (34D) is boosted to high-pressure LNG (34E) and then sent back to the cold box of the oxygen production workshop (1C) to recover the cold energy of the LNG, which is converted into SNG and then sent to the gas turbine (34A) for power generation peak shaving; when the NGCC combined cycle only supplies power to the polygeneration system, the liquefied methane in the cold box of the hydrogen-methane liquefaction separation device (34) is not depressurized, but directly exchanges its cold energy with the raw material gas to be liquefied, which is converted into gaseous SNG and then sent to the gas turbine (34A) for power generation.

[0043] 4. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method according to the present case, characterized in that the raw coal is a carbon-containing solid material such as lignite, bituminous coal, coke, anthracite, or briquette. When non-caking coal is mined, a slag-breaking rotary disk (8) is not provided in the gas furnace.

[0044] 5. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method according to the present case, characterized in that the source of oxygen required for producing water gas is the oxygen by-produced by the electrolytic water hydrogen production device or the oxygen produced by air separation oxygen production.

[0045] 6. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method according to the present case, characterized in that the height-diameter ratio of the gasification bed in the hydrogen gas section is 2.0-4; the height-diameter ratio of the gasification bed in the hydrogen gas section is inversely proportional to the gasification activity of the raw coal. For high-activity coal coke, a smaller height-diameter ratio is adopted, and for low-activity coal coke, a larger height-diameter ratio is adopted. The inner diameter of the production furnace is 1.2-2 meters, or 2.2-4 meters, or 4.2-6 meters; the working pressure is 3-5 MPa, or 5.1-8 MPa.

[0046] 7. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method according to this case, characterized in that the raw coal or briquette has a particle size of 3-10 mm, or 11-40 mm, or 41-80 mm.

[0047] 8. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method according to this case, characterized in that in the hydrogen gasification agent entering each hydrogen gasification layer in the hydrogen coal gas section, 0-15% of steam is respectively added to prevent the over-temperature of the hydrogen gasification layer; the cooling water in the jacket of the pressure-bearing shell in the hydrogen coal gas section and the cooling water in the jacket of the pressure-bearing shell in the water coal gas section are circulated separately.

[0048] 9. A low-carbon coal-based polygeneration LNG energy storage NCCC power generation peak shaving method according to this case, characterized in that the water coal gas section has a dry slag removal gasification method with the highest temperature below the ash fusion point temperature, or a slag gasification method with the highest temperature above the ash fusion point temperature.

[0049] 10. A low-carbon coal-based polygeneration LNG energy storage NCCC power generation peak shaving method according to this case, characterized in that the process power of the coal-based polygeneration system is provided by multiple surrounding wind-solar power farms at the location of the device, so as to increase the power supply rate of wind-solar power and reduce the carbon emissions of the coal-based polygeneration.

[0050] Adopting the present invention has the following positive effects:

[0051] Since methane is produced by directly hydrogenating coal, the consumption of hydrogen, water gas, steam and oxygen is greatly reduced, and thus the raw coal fuel entering the product, the fuel coal for producing steam, and the power coal for driving pumps and motors are greatly reduced; in addition, since the residual coke temperature entering the water coal gas section reaches above 300 °C and there is no consumption of the heat of vaporization of moisture and the heat of pyrolysis and dry distillation, the thickness of the water gas reaction layer is greatly increased, and thus the steam decomposition rate is increased. While reducing the process waste heat, it also reduces the oxygen consumption and the generation of CO 2 is reduced, so that the pure O 3 consumption for producing 1000 Nm 4 of CH 2 + 250 kg of fuel oil is reduced to below 330 Nm 3 , which is much lower than the oxygen consumption of the traditional two-step entrained flow coal-to-fuel and natural gas processes, and the thermal efficiency including oxygen production is increased by 15 percentage points;

[0052] Since pressurized moving bed gas-solid countercurrent direct coal hydrogenation is used to synthesize methane, the reaction heat of methane synthesis can easily become the heat source for internal pyrolysis and dry distillation of the raw material, and thus nearly zero-carbon emission production of coal tar can be realized; when hydrogen produced by wind-solar power is used to generate fuel oil, almost no carbon emissions occur during the entire coal-based fuel oil production process. Therefore, using the coal-to-fuel oil method of this case will greatly reduce the carbon emissions compared with the traditional one-step or two-step coal-to-oil methods, and even achieve nearly zero emissions.

[0053] When there is no need to absorb wind and photovoltaic power, the coal tar hydrogenation to fuel oil unit (4D), the electrolyzed water to hydrogen unit (1D), and the methanol synthesis unit (25B) can all be shut down or operated at low load. Special public works for these three units do not need to be set up, thus reducing the investment in the units. When it is necessary to start the electrolyzed water to hydrogen to absorb wind and photovoltaic power, it can be quickly put into operation;

[0054] Even without wind and photovoltaic power, for the three major products of methanol, fuel oil, and LNG, due to the full utilization of the strong exothermic reaction of C + 2H 2 = CH 4 and the oxygen consumption of coal gasification reduced from 1000 Nm 3 CO + H 2 consuming 350 Nm 3 in the current entrained flow bed to 200 Nm 3 in this process, the standard coal consumption of raw coal plus fuel coal for producing coal-based LNG and fuel oil in this process is reduced by 30%, and the standard coal consumption of raw coal plus fuel coal for producing coal-based methanol is reduced by 20%. When the LNG stored in this case is used to become SNG for NGCC power generation peaking after recovering cold energy, the function of low-carbon coal-based polygeneration LNG energy storage NGCC power generation peaking can be realized.

[0055] Especially for large-scale medium and long-term energy storage of more than 300 hours, due to the huge low-cost energy storage advantage of LNG, the NGCC grid-connected electricity cost of this case will be much lower than the power supply cost of other energy storage by more than 90%. Brief Description of the Drawings

[0056] Figure 1 It is a simplified process diagram of a low-carbon coal-based polygeneration LNG energy storage NGCC power generation peaking process described in this case;

[0057] Figure 2 It is a simplified diagram of the gasifier to illustrate its related structure.

[0058] In the figure:

[0059] 1 Oxygen-enriched steam and inlet;

[0060] 1A Oxygen-enriched steam and its pipeline;

[0061] 1B Oxygen and pipeline;

[0062] 1C Air separation oxygen production and workshop device;

[0063] 1D Electrolyzed water to hydrogen and oxygen unit;

[0064] 1E Oxygen and pipeline;

[0065] 2 Water gas outlet and water gas;

[0066] 3 Hydrogen gasification agent and pipeline for furnace charging;

[0067] 3A Hydrogen inlet and pipeline for high-temperature hydrogen gasification layer;

[0068] 3a Hydrogen inlet and pipeline for the central area of high-temperature hydrogen gasification layer;

[0069] 3B Hydrogen inlet and pipeline for medium-temperature hydrogen gasification layer;

[0070] 3b Hydrogen inlet and pipeline for the central area of medium-temperature hydrogen gasification layer;

[0071] 3C Hydrogen inlet and pipeline for low-temperature hydrogen gasification layer;

[0072] 3c Hydrogen inlet and pipeline for the central area of low-temperature hydrogen gasification layer;

[0073] 3D Rich hydrocarbon hydrogen gas outlet;

[0074] 4 Raw coal and coal conveying device;

[0075] 4A Raw coal drying device;

[0076] 4B Dried raw coal and coal conveying device;

[0077] 4C Coal lock;

[0078] 4D Coal tar hydrogenation to fuel device;

[0079] 4D1 Ammonia water and its pipeline;

[0080] 4D2 Hydrogen sulfide and pipeline;

[0081] 4D3 Fuel and pipeline;

[0082] 4D4 Fuel storage device;

[0083] 5 Coal distributor;

[0084] 6 Hydrogenation drying layer;

[0085] 7 Hydrogenation pyrolysis and dry distillation layer;

[0086] 8 Cracking rotary disc;

[0087] 8A Hollow drive shaft;

[0088] 8B Driving device;

[0089] 9 Semi-coke gasification layer;

[0090] 10 Low-temperature hydrogen gasification layer;

[0091] 10A Low-temperature hydrogenation distributor;

[0092] 10B Low-temperature hydrogenation central area distributor;

[0093] 10C Low-temperature hydrogenation central area intake sleeve

[0094] 10D Low-temperature annular channel

[0095] 11 Medium-temperature hydrogenation gasification layer

[0096] 11A Medium-temperature hydrogenation distributor

[0097] 11B Medium-temperature hydrogenation central area distributor

[0098] 11C Medium-temperature hydrogenation central area intake sleeve

[0099] 11D Medium-temperature annular channel

[0100] 11E Thermocouple insertion sleeve

[0101] 11F Thermocouple socket

[0102] 12 High-temperature hydrogenation gasification layer

[0103] 12A High-temperature hydrogenation distributor

[0104] 12B High-temperature hydrogenation central area distributor

[0105] 12C High-temperature hydrogenation central area inlet pipe

[0106] 12D Annular channel

[0107] 13 Residual coke isolation area

[0108] 14 Circumferential drive spiral discharger

[0109] 14A Residual coke downward movement channel pressure-bearing cylinder

[0110] 15 Coal gas collection area

[0111] 16 Water gas reaction layer

[0112] 17 Oxygen combustion layer

[0113] 18 Ash layer

[0114] 18A Grate

[0115] 19 Water gas section shell

[0116] 19A Hydrogen gas section shell

[0117] 19B Jacket steam

[0118] 20 Ash lock

[0119] 21 High-temperature water gas and pipeline

[0120] 22 Waste heat boiler with dust removal;

[0121] 22A Steam and pipelines;

[0122] 23 Medium-temperature water gas and pipelines;

[0123] 24 Fine dust removal and desalination device;

[0124] 25 Purified water gas and pipelines;

[0125] 25A Water gas for producing methanol and pipelines;

[0126] 25B Methanol synthesis device;

[0127] 25C Methanol and its pipelines;

[0128] 25D Methanol storage and device;

[0129] 26 CO shift process device;

[0130] 26A Steam and its pipelines, produced from shift waste heat boiler;

[0131] 27 Shift gas and pipelines;

[0132] 28 NHD desulfurization and PSA decarbonization device;

[0133] 28A Hydrogen (make-up hydrogen) produced by PSA pressure swing adsorption separation device and pipelines;

[0134] 28B Hydrogen sulfide gas separated by desulfurization device and pipelines;

[0135] 28C Combustible tail gas separated by PSA and pipelines;

[0136] 29 Supercritical waste heat boiler;

[0137] 29 Flue gas and its pipelines;

[0138] 29B Deep energy-saving air-cooled island;

[0139] 29C Supercritical steam turbine;

[0140] 29D Generator;

[0141] 29E Steam and its pipelines;

[0142] 29F Oxygen production power electricity and cables;

[0143] 31 Rich hydrocarbon hydrogen gas and pipelines;

[0144] 32 Rich hydrocarbon hydrogen gas dust removal - heat recovery - cooling - oil-water separation - CO shift - CO 2 and sulfur-containing gas removal and separation purification device;

[0145] 32A Heat-conducting liquid return pipeline;

[0146] 32B Heat-conducting liquid outlet pipeline;

[0147] 32C Coal gas organic wastewater and pipeline;

[0148] 32C1 Coal gas organic wastewater treatment device;

[0149] 32D Phenol-ammonia coal gas water and pipeline;

[0150] 32E Crude coal tar and pipeline;

[0151] 32F Hydrogen sulfide and pipeline;

[0152] 32G Sulfur production device;

[0153] 32H Coal tar storage device;

[0154] 33 Methane hydrogen and pipeline;

[0155] 34 Hydrogen-methane liquefaction and separation device;

[0156] 34A One or more sets of gas turbines and NGCC combined cycle power generation units;

[0157] 34B Generator supporting the gas turbine;

[0158] 34C Hydrogen and pipeline sent from the electrolytic water hydrogen production device or the hydrogen-methane liquefaction and separation device (34) to the coal tar to fuel oil device (4D);

[0159] 34D Liquefied natural gas LNG storage device

[0160] 34E High-pressure LNG and return pipeline;

[0161] 34F Combustible tail gas and pipeline separated by the hydrogen-methane liquefaction and separation device (34);

[0162] 35 Recirculating hydrogen and pipeline;

[0163] 36 Hydrogen and main pipeline;

[0164] 37 Hydrogen circulator;

[0165] 38 Heater and its pipeline;

[0166] H 2 Hydrogen, O 2 Oxygen, CO 2 Carbon dioxide, H 2 S Hydrogen sulfide, SNG Synthetic natural gas, LNG Liquefied natural gas, MeOH Methanol, TFDL Peak shaving power, LH Sulfur, RY Fuel oil, FA Phenol-ammonia; Logistics direction. Specific implementation method

[0167] Construct according to the overall design plan.

[0168] First, manufacture the water gas section and the hydrogen gas section with an inner diameter of 3.8 meters respectively, then transport them to the installation site. After connecting them into a firm whole with the pressure-bearing cylinder body (14A) of the residual coke downward movement channel equipped with a circumferential drive screw discharger (14), install the internal components of the water gas section and the hydrogen gas section, and conduct single-unit trial operation, leak detection, and pressure test to be qualified. After installation in place, process piping, electrical instrument installation, anti-corrosion and heat insulation, system leak detection, pressure test, and trial operation and debugging are qualified. Add demineralized water to the jackets of the water gas section and the hydrogen gas section of the gasifier to make it have the internal and external structures and functions of the hydrogen gas section and the water gas section.

[0169] Then, lay 300 mm thick gas furnace ash and slag on the grate of the water gas section in sequence, and lay coke with a particle size of 20 - 50 mm and a thickness of 2000 mm required for the water steam gasification layer; add coke with a particle size of 20 - 50 mm and a thickness of 2000 mm to each hydrogenation gasification layer of the hydrogen gas section, add 2000 mm thick semi-coke to the semi-coke hydrogenation gasification layer, add weakly caking coal with a particle size of 20 - 50 mm and a thickness of 2000 mm to the dry distillation layer, and add weakly caking coal with a particle size of 20 - 80 mm and a thickness of 1000 mm to the drying layer;

[0170] ① Feed air into the furnace at a flow rate of 5000 - 10000 Nm 3 / h and a temperature rise rate of 30 °C / h, and vent it at the water gas outlet (2); after about 6 hours, since the ignition point of coke is about 350 °C, the oxygen combustion layer (17) in the water gas section will start to show a phenomenon that the temperature exceeds the temperature of the incoming air. When the oxygen combustion layer rapidly rises to about 700 °C, nitrogen can be added to the incoming air to reduce its O 2 content to control the temperature rise rate of the oxygen combustion layer at about 50 °C / h. After the temperature of the oxygen combustion layer reaches 900 - 1000 °C, gradually change the incoming air heating to an oxygen - water steam mixed gasifying agent and control its temperature from rising further to prevent overheating and coking in the water gas section.

[0171] ② Feed nitrogen into the hydrogen gas section at a flow rate of 5000 - 10000 Nm 3 / h through the hydrogen inlets (3A), (3B), (3C), (3a), (3b), (3c) of the hydrogen gas section and vent it at the hydrogen gas outlet. To further heat the coke, semi-coke, and raw coal in the hydrogen gas section, after the bed hot spot temperature is greater than 150 °C, an appropriate amount of air (actually oxygen, note: the maximum temperature of the coke hydrogenation gasification layer and the semi-coke hydrogenation gasification layer shall not exceed 700 °C) can be supplemented to utilize the combustion heat of oxygen and coke to accelerate the temperature rise rate;

[0172] ③ When the temperature of the dry distillation layer in the hydrogen coal gas section is greater than 400 °C, the sticky-breaking rotating disc (8), the circumferential driving screw discharger (14), and the furnace grate (18A) can be started to run at a low speed in real time, and the self-control loop of the coal feeding device is started to automatically add raw coal in a timely manner.

[0173] ④ When the highest temperature of each hydrogenation gasification layer and the semi-coke hydrogenation gasification layer reaches 600 °C or above, the system starts to boost the pressure at a rate of 1 MPa per hour. During the pressure boosting process, attention should be paid to: reducing the pressure difference between the water gas outlet and the hydrogen inlet to approach zero to prevent the gas in the hydrogen coal gas section from flowing downward into the water gas collector and flowing out from the water gas outlet.

[0174] ⑤ When the pressure rises to 2 MPa, turn off the oxygen in the hot nitrogen added for 30 minutes, or turn off the oxygen. After the hot spot temperature drops by 50 °C, change the hot nitrogen entering the furnace to hot hydrogen and feed it into the furnace at a flow rate of 5000 - 10000 Nm 3 / h, so that the hydrogen coal gas section enters the hydrogen gasification period, and gradually increases at a rate of 1 MPa per hour, and finally stabilizes the pressure at 4 MPa.

[0175] Furnace temperature control: In the water gas section, the temperature of the oxygen combustion layer is controlled to be 30 - 80 °C below the ash fusion point through the steam-oxygen ratio entering the furnace; in the hydrogen coal gas section, the highest temperature of the semi-coke hydrogenation section is controlled to be ≤1000 °C by controlling the hydrogen temperature, the methane content in the hydrogen, and the hydrogen flow rate of each hydrogenation gasification layer;

[0176] Control of the composition of rich hydrocarbon hydrogen coal gas: The methane content in the rich hydrocarbon hydrogen coal gas is controlled to be about 45 - 50% according to the activity and volatile content of the coal type by controlling the hydrogen flow rate, temperature, and methane content entering the furnace. The content of other gaseous hydrocarbons is 100 - 200 g / Nm 3 Hydrogen coal gas.

[0177] Regarding the heat recovery, cooling, tar separation, water separation, phenol-ammonia recovery, CO conversion, and hydrogen sulfide / CO 2 separation of rich hydrocarbon hydrogen coal gas, it is a conventional project, and it can be designed, installed, debugged, and put into operation according to the specifications;

[0178] Since the hydrogen source for coal tar hydrogenation to produce fuel is hydrogen produced by wind-solar power generation, due to the fluctuating and intermittent characteristics of wind-solar power, the scale and regulation performance design of the coal tar hydrogenation to produce fuel device and its coal tar storage tank capacity should take into account the fluctuating and intermittent characteristics brought by wind-solar power generation;

[0179] For the deep cryogenic separation of hydrogen and methane, LNG energy storage, and NGCC power generation peak shaving, the three should not only take into account the stability requirements of coal-based polygeneration, but also shoulder the demand for LNG to be converted into SNG for NGCC power generation peak shaving. The cold box for the deep cryogenic separation of hydrogen and methane should be equipped with an LNG energy recovery component and a cold energy / energy balance coordination control scheme:

[0180] Regarding hydrogen production by electrolyzing water and methanol synthesis; when a wind-solar power-consuming electrolytic water hydrogen production device is put into operation, it will inevitably disrupt the system balance of a simple coal-based polygeneration system. The methanol synthesis system equipment should be started in a timely manner to convert the excess water gas plus appropriate electrolytic water hydrogen into methanol.

[0181] Since the water vapor contained in the hydrocarbon-rich hydrogen gas only comes from the raw coal, that is, the physical moisture adsorbed by the coal entering the furnace and the combined water generated by pyrolysis, its content is not only a key determining factor for the outlet temperature of the hydrocarbon-rich hydrogen gas but also a key factor for the amount of coal gas wastewater. Therefore, in this case, a raw coal atmospheric drying (4A) device is added before the raw coal enters the gasifier, and the heat in the hydrocarbon-rich hydrogen gas is transferred to the heat source for raw coal drying by using a circulating heat transfer fluid and a circuit (32A / B) to reduce the moisture in the raw coal, thereby effectively reducing the organic wastewater in the coal gas.

[0182] Regarding waste heat recovery, purification and separation, and hydrogen production of water gas:

[0183] Since the raw coal of the water gas in this case is all hydrogenated gasification coke, there is no tar in the coal gas and the methane content is also low. The temperature is about 700 °C. The outlet water gas can use an ordinary dry cyclone dust collector to remove more than 98% of the dust, and then pass through a hydrogen heater and a steam superheater to cool down by 200 - 300 °C and enter the waste heat steam boiler to convert the heat into process steam heat energy. The temperature drops to about 250 °C. A simple-structured and low-water-volume cyclone plate washing and waste heat recovery device is used to convert the excess water vapor in the water gas into the water vapor required for coal gasification. Since the water vapor content in the coal gas is too high, it will cause the CO shift catalyst to overheat and deactivate. Converting the excess water vapor in the coal gas into water vapor that can be re-fed into the furnace not only protects the CO shift catalyst but also obtains gasification water vapor and reduces the discharge of coal gas sewage.

[0184] Since the ultimate goal of water gas production is to produce hydrogen for hydrogenation coal gasification and coal tar hydrogenation to produce fuel aromatics. For the CO shift in water gas, using the water vapor in it, a deep shift with a conversion rate of more than 97% is adopted to obtain as much hydrogen as possible. The gas after the shift is called the shifted gas. After heat recovery, cooling and water separation, the water vapor content drops below 0.25%. Its main components are H 2 and CO 2 , since pressure swing adsorption PSA is a dry decarbonization method that does not consume water, has a simple process, low energy consumption, high automation, and a hydrogen recovery rate of up to 98%; the hydrogen separated in the PSA adsorption step is sent as supplementary hydrogen (28A) for producing hydrocarbon-rich hydrogen gas into the hydrogen main pipe (36). The desorbed gas separated in the early stage of the desorption step contains a small amount of CO, CH 4 combustibles, and its heat is greater than 1000 kJ / Nm 3The low calorific value gas is sent through a dedicated recovery pipeline to the gas turbine exhaust boiler to produce steam, achieving the best use of resources. The high-purity CO separated in the later stage of the desorption step 2 The desorbed gas, with a content greater than 98%, can be used for other purposes or vented.

[0185] It is necessary to change the yield ratio of oil and gas (natural gas / fuel aromatic hydrocarbons). This can be achieved by changing the outlet temperature of the gasifier, the composition and flow rate of the hydrogen gasifying agent entering the gasifier, the process pressure of the gasifier, the coal feeding rate, the flow rate ratio of hydrogen to oxygen-enriched steam, and the type of raw coal. Using old anthracite, no coal tar is produced, and natural gas can be produced entirely. Using low-rank lignite rich in coal tar, combined with other process operations beneficial to increasing the production of coal tar, the coal tar yield can reach 400 kg / km 3 SNG.

[0186] The above content is only to illustrate the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any modification made on the basis of the technical solution according to the technical idea proposed by the present invention falls within the protection scope of the claims of the present invention.

Claims

1. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method, characterized by: The pressurized moving bed gasifier is designed to be a pressurized moving bed gasifier with an upper and lower section structure, wherein the upper section is a hydrogen gas section and the lower section is a water gas section, and the pressurized moving bed gasifier is connected by a residual coke isolation zone (13) and a residual coke downward passage pressure-bearing cylinder (14A) provided with an annular driven spiral discharger (14) therein, as shown in FIG2; by controlling the rotation speed of the annular driven spiral discharger (14), the rate at which the residual coke in the hydrogen gas section enters the water gas section is adjusted, and then the production load of the entire pressurized moving bed gasifier and the gasification ratio of the raw coal in the upper and lower sections are controlled by coordinating the addition amount of the raw coal (4) and the addition amount of the hydrogen gasifying agent (3) in the hydrogen gas section, the rotation speed of the grate (18A) in the water gas section and the addition amount of the oxygen-enriched steam (1) in the water gas section; at the same time, the isolation effect of the spiral blades of the spiral discharger is utilized to reduce or eliminate the blowby between the water gas section and the hydrogen gas section; The lower section of the pressurized moving bed gasifier is designed to use oxygen-enriched steam gasification agent formed by a mixture of oxygen and water vapor, and the residual coke from the hydrogen gas section as raw material to produce a water gas section with hydrogen and carbon monoxide as main components through the reactions of C+O2=CO2 and C+H2O=CO+H2; the source of oxygen is the oxygen produced as a byproduct of the water electrolysis hydrogen production device (1D), or the oxygen produced by the air separation oxygen production workshop (1C), or both; The upper section of the pressurized moving bed gasifier is designed to use a hydrogen gasifying agent (3) with methane ≤ 3%, hydrogen ≥ 80%, CO + CO2 + N2 ≤ 3%, H2S ≤ 0.1%, and water vapor ≤ 15%, i.e., hydrogen as the main component, and a briquette made of crushed coal or pulverized coal with a particle size of 3 to 80 mm as a raw material, and directly produce methane through the chemical reaction of C + 2H2 = CH4. At the same time, the zero carbon emission heat released by the chemical reaction of C + 2H2 = CH4 is directly used for pyrolysis and dry distillation of raw coal to produce coal tar by using a gas-solid countercurrent process, that is, the zero carbon emission heat release, pyrolysis of raw coal, and near zero carbon emission heat release are used to produce coal tar. Carbon emission produces coal tar; the upper section of the pressurized moving bed gasifier is designed as a hydrogen gas section that produces methane and coal tar hydrocarbon-rich coal gas by coal hydrogenation gasification; the amount of water vapor added to the hydrogen is controlled to make an appropriate amount of heat-absorbing water gas reaction C+2H2O=CO+H2, directly absorbing the heat released by the coal hydrogenation C+2H2=CH4 chemical reaction, thereby avoiding overheating and coking of the gasification bed in the hydrogenation gasification section, and effectively controlling the adverse effect of the transient increase in bed temperature on increasing the methane concentration, and also replenishing hydrogen raw materials for more coal hydrogenation C+2H2=CH4 chemical reactions; The water gas (21) from the water gas outlet (2) is sent to the dust removal waste heat boiler (22) for heat recovery and to the fine dust removal and desalination device (24) for purification. When it is necessary to absorb the wind and photovoltaic power, part of the water gas (25A) is sent to the methanol synthesis device (25B) to synthesize methanol together with the hydrogen produced by the wind and photovoltaic power water electrolysis hydrogen / oxygen device (1D). The methanol is then sent to the methanol storage tank (25D) through the pipeline (25C). The process pump also adopts the wind and photovoltaic power generation method. When the coal-to-methanol production process is completed, near-zero CO2 emission can be achieved; when there is no need to absorb wind and solar power, all the water gas (21) is converted into hydrogen by the CO conversion device (26) with 97% of CO therein converted into hydrogen, and then sent to the NHD desulfurization PSA decarbonization device (28) for desulfurization and decarbonization, and the separated hydrogen is used as supplementary hydrogen (28A) consumed by direct coal hydrogenation to produce methane, and is sent to the hydrogen main inlet (36) of the hydrogen circulation machine (37) for direct coal hydrogenation to synthesize methane; The hydrocarbon-rich coal gas (31) from the hydrogen-rich coal gas outlet (3D) of the hydrogen-rich coal gas section is purified by a device (32) for dust removal, heat recovery, cooling, separation of coal tar and water, CO conversion, separation and purification of acid gases such as hydrogen sulfide and CO2 to become a pure methane-hydrogen (33) mixed gas, and then enters a hydrogen-methane liquefaction separation device (34) for methane liquefaction separation; The separated liquefied methane LNG is sent to the LNG storage tank (34D) for temporary storage to be used for NGCC power generation peak regulation or sale; when it is necessary to consume wind and solar power, the refrigeration power electricity required for methane liquefaction separation and the power electricity required for the operation of the entire coal-based polygeneration system are provided by wind and solar power, so that wind and solar power are converted into low-cost storage using LNG as a carrier through this process; when there is no wind and solar power, methane liquefaction and all power are provided by self-produced methane or self-produced LNG after recovering cold energy through NGCC power generation; when NGCC power generation peak regulation is needed, the LNG stored in the LNG storage tank (34D) is pressurized and sent to the hydrogenation plant through pipeline (34E) The cold box of the methane liquefaction separation device (34) or the air separation oxygen production (1C) exchanges the cold energy of LNG with the methane or oxygen that needs to be liquefied, and then becomes synthetic natural gas (SNG) at room temperature, which is then sent to the gas turbine (34A) of the NGCC combined cycle unit for power generation and peak regulation. This not only recovers the cold energy stored in LNG, but also greatly reduces the power consumption demand for methane hydrogen (33) liquefaction separation and air separation oxygen production (1C) refrigeration when the power grid needs power generation and peak regulation. When wind and solar power are needed, the NGCC generator set can be operated at a low load or stopped, so that the system can consume wind and solar power in full, and can also reduce carbon emissions from coal-based multi-generation. The crude coal tar (32E) separated from the separation and purification device (32) is first sent to the coal tar storage device (32H) for temporary storage or buffering by utilizing the storability of coal tar; when it is necessary to consume wind and solar power, it is then sent to, or with increased load, the coal tar fuel oil device (4D) to complete fuel oil production together with the hydrogen (34C) produced by the water electrolysis hydrogen and oxygen device (1D) from wind and solar power; since the heat source for producing coal tar comes from the heat released by direct hydrogenation of zero-carbon-emission coal to produce methane, when it is necessary to consume wind and solar power, the hydrogen produced by wind and solar power is used to generate fuel oil, and the entire coal-based fuel oil generation process has almost no carbon emissions. Therefore, when the coal-to-fuel oil in this case is used, when the process power is also wind and solar power, near-zero CO2 emissions can be achieved; The hydrogen gas section is designed from bottom to top as follows: A high-temperature coke hydrogenation gasification layer (12) is provided with a high-temperature hydrogenation gasification layer hydrogen inlet (3A), an annular channel (12D), a high-temperature hydrogenation distributor (12A), a high-temperature hydrogenation central area air inlet pipe (12C), and a high-temperature hydrogenation central area distributor (12B) at its lower part; hydrogen from the hydrogen inlet (3A) enters the annular area of ​​the high-temperature coke hydrogenation gasification layer (12) except the central area through the annular channel (12D) and the distributor (12A); hydrogen from the central area air inlet pipe (12C) enters the central area of ​​the high-temperature coke hydrogenation gasification layer (12) through the central area distributor (12B), thereby achieving uniform distribution of hydrogen in the high-temperature coke hydrogenation gasification layer (12); A medium-temperature hydrogenation gasification layer (11) is provided with a medium-temperature hydrogenation distributor (11A), a medium-temperature hydrogenation central region distributor (11B), a medium-temperature hydrogenation central region air inlet sleeve (11C), and a medium-temperature annular channel (11D) at its lower part; hydrogen from a hydrogen inlet (3B) enters the annular region of the medium-temperature hydrogenation gasification layer (11) except the central region through the medium-temperature annular channel (11D) and the medium-temperature hydrogenation distributor (11A); hydrogen from the medium-temperature hydrogenation central region air inlet sleeve (11C) enters the central region of the medium-temperature hydrogenation gasification layer (11) through the medium-temperature hydrogenation central region distributor (11B), thereby achieving uniform distribution of hydrogen in the medium-temperature hydrogenation gasification layer (11); A low-temperature hydrogenation gasification layer (10) is provided with a low-temperature hydrogenation distributor (10A), a low-temperature hydrogenation central region distributor (10B), a low-temperature hydrogenation central region air inlet sleeve (10C), and a low-temperature annular channel (10D) at its lower part; hydrogen from a hydrogen inlet (3C) enters the annular region of the low-temperature hydrogenation gasification layer (10) except the central region through the low-temperature annular channel (10D) and the low-temperature hydrogenation distributor (10A); hydrogen from the low-temperature hydrogenation central region air inlet sleeve (10C) enters the central region of the low-temperature hydrogenation gasification layer (10) through the low-temperature hydrogenation central region distributor (10B), thereby achieving uniform distribution of hydrogen in the low-temperature hydrogenation gasification layer (10); Semi-coke hydrogenation gasification layer (9), mainly for solid unsaturated hydrocarbon hydrogenation: C X H Y +(2X-0.5Y)H2=XCH4, a reaction to produce methane; A hydropyrolysis retorting layer (7) is provided, and a debonding turntable (8) is provided between the hydropyrolysis retorting layer (7) and the semi-coke hydrogasification layer (9); the power for driving the debonding turntable (8) is provided by a driving device (8B) provided on the top of the gasifier, which drives its coaxial hollow transmission shaft (8A), so that the coal particles cannot be bonded into particles larger than 50 mm and enter the semi-coke hydrogasification layer (9); Hydrogenation drying layer (6); Coal distributor (5); During normal production: ① 30-40% of the total amount of hydrogen (3) entering the furnace is uniformly introduced into the lower circular section of the high-temperature hydrogenation gasification layer (12) through the bottom inlet (3A) of the hydrogen coal gas section, the annular channel (12D), the high-temperature hydrogenation distributor (12A), the high-temperature hydrogenation central area air inlet pipe (12C), and the high-temperature hydrogenation central area distributor (12B), and then flows upward in the reverse direction with the high-temperature coke of about 1050°C downward to exchange heat, heating the room-temperature hydrogen to 900-950°C, so that the hydrogen and the active carbon elements in the high-temperature coke undergo an exothermic methanogenic reaction of C+2H2→CH4, while increasing the gaseous methane content, and also increasing the hot spot temperature of the high-temperature coke hydrogenation gasification layer (12) to 1050°C below the ash melting point of coal, so that the gaseous methane concentration reaches 10-15% and flows upward; ② The gas phase with a methane concentration of 10-15% ascends and mixes with the low-temperature hydrogen (30-40%) of the total amount of hydrogen (3) entering the furnace from the hydrogen inlet (3B) of the medium-temperature hydrogenation gasification layer, through the medium-temperature annular channel (11D), the medium-temperature hydrogenation distributor (11A), the medium-temperature hydrogenation central area air inlet sleeve (11C), and the medium-temperature hydrogenation central area distributor (11B). The temperature is reduced to 850-900°C and continues to ascend into the medium-temperature hydrogenation gasification layer (11), so that the hydrogen therein and the active carbon elements in the medium-temperature hydrogenation gasification layer (11) undergo a methanogenic exothermic reaction of C+2H2→CH4 again, and while the gas phase methane content continues to increase, the hot spot temperature of the medium-temperature hydrogenation gasification layer (11) is also increased to 950-1000°C, and the gas phase methane concentration reaches the range of 15-20% and continues to ascend; ③ The gas phase with a methane concentration of 15-20% moves upward and mixes with the low-temperature hydrogen (3) accounting for 20-30% of the total amount of hydrogen (3) entering the furnace, from the hydrogen inlet (3C) of the low-temperature hydrogenation gasification layer, through the low-temperature annular channel (10D), the low-temperature hydrogenation distributor (10A), the low-temperature hydrogenation central area air inlet sleeve (10C), and the low-temperature hydrogenation central area distributor (10B). The temperature is reduced to 800-850°C and continues to move upward into the low-temperature hydrogenation gasification layer (10), so that the hydrogen therein and the active carbon elements in the low-temperature hydrogenation gasification layer (10) undergo a methanogenic exothermic reaction of C+2H2→CH4 again, while the gas phase methane content continues to increase, and the hot spot temperature of the low-temperature hydrogenation gasification layer (10) is also increased to 900-950°C below the ash melting point of the coal, and the gas phase methane concentration reaches the range of 20-25% and continues to move upward; ④ The gas phase with a methane concentration of 20-25% moves upward into the semi-coke gasification layer (9) and combines with the solid unsaturated hydrocarbons C in the semi-coke from the hydropyrolysis distillation layer (7) and moves downward to the semi-coke gasification layer (9) via the debonding turntable (8). X H Y conduct: C X H Y +(2X-0.5Y)H2=XCH4, hydrogenation reaction generates methane, so that the gas phase methane concentration reaches 40-45%, and the hot spot temperature of the semi-coke gasification layer (9) reaches 750-800°C; ⑤ The gas phase with a methane concentration of 40-45% continues to ascend, passes through the debonding turntable (8) and ascends to the hydrogenation pyrolysis distillation layer (7), and then transfers heat to the bed layer, so that the coal particles at a temperature of about 300°C from the drying layer (6) are gradually heated to 600°C, and the coal tar is decomposed by heat to separate out the coal tar, which is then gasified by heat. Part of the coal tar is hydrogenated and gasified into tar vapor and enters the gas phase, and part of the coal tar is distilled and converted into solid unsaturated hydrocarbons C X H Y ; Due to the high content of gas phase methane, its higher methane partial pressure P CH4 The pyrolysis methane of coal will be reduced and the yield of tar gas will be relatively increased; the hydrogenation pyrolysis of coal and tar will further reduce the hydrogen content in the gas phase and increase the methane concentration to 45-50%; ⑥ The gas phase rich in methane and tar continues to move upward into the drying layer (6). While transferring heat to the bed layer, the moisture adsorbed in the coal is heated and gasified into the gas phase, causing the coal particles to be heated and dried; In the hydrogen coal gas section, through the above process ① to ⑥, the production of hydrocarbon-rich hydrogen coal gas (31) is achieved with raw coal and hydrogen as raw materials, methane as the main product and coal tar as the secondary product, and the hydrocarbon-rich hydrogen coal gas leaves the coal gasifier through the hydrocarbon-rich hydrogen coal gas outlet (3D); During normal production: the oxygen-containing gasifying agent composed of a mixture of oxygen and water vapor enters the gasifier from the oxygen-rich water vapor inlet (1) at the bottom of the water gas section of the gasifier, passes through the grate (18A) from bottom to top, passes through the ash layer (18), absorbs the heat carried by the ash, and the temperature rises to about 600°C before entering the oxygen combustion layer (17). The oxygen in the gasifying agent causes the remaining carbon elements in the residual coke to burn and gasify rapidly, generating CO2 and releasing a large amount of heat, so that the water vapor in the gasifying agent and the bed temperature reach above 1000°C, below the ash melting point; the high temperature containing CO2 The water vapor transfers heat from bottom to top to the residual coke in the water-gas reaction layer (16), and at the same time reacts with the carbon elements in the residual coke to undergo an endothermic water vapor gasification reaction C+H2O=CO+H2, so that most of the carbon elements in the residual coke react with 30-40% of water molecules in the water vapor and are converted into CO and H2 in the raw gas. The raw gas becomes wet hot coal gas with a temperature of about 700°C, enters the gas gathering area (15) above the water-gas reaction layer (16), and then flows out of the water-gas section of the gasifier through the water-gas outlet (2). At this point, the water-gas section completes the water-gas production.

2. According to claim 1, a low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method is characterized by: Temperature measuring thermocouples are arranged at vertical intervals of 250 mm in the water gas section and hydrogen gas section of the gasifier to monitor their temperatures; pressure detection points are arranged at the near-material end of the residual coke isolation zone (13) and the outlet end of the annular driven spiral discharger (14) to accurately control the pressure difference between the upper and lower ends, so as to reduce and eliminate gas blowby between the hydrogen gas section and the water gas section.

3. The low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak-shaving method according to claim 1 is characterized in that: The raw coal entering the furnace undergoes top-down heating, dehydration and drying, pyrolysis and distillation, semi-coke hydrogenation and rapid gasification, low-temperature hydrogenation and gasification, medium-temperature hydrogenation and gasification, and high-temperature hydrogenation and gasification in the hydrogen gas section. The total mass is reduced by 40-55% and the carbon element is reduced by 30-50% depending on the type of coal, ash content, and moisture content, and becomes residual coke.

4. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method according to claim 1, characterized in that: When LNG is needed for peak load shifting of power generation, the LNG stored in the LNG storage tank (34D) is pressurized into high-pressure LNG (34E) and then sent back to the cold box of the oxygen production workshop (1C), where the cold energy of the LNG is recovered, converted into SNG and then sent to the gas turbine (34A) for peak load shifting of power generation; when the NGCC combined cycle only supplies power to the cogeneration system, the liquefied methane in the cold box of the hydrogen-methane liquefaction and separation device (34) is not depressurized, but its cold energy is directly exchanged with the raw gas to be liquefied, converted into gaseous SNG and then sent to the gas turbine (34A) for power generation.

5. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method according to claim 1, characterized in that: The raw coal is a carbonaceous solid material such as lignite, bituminous coal, coke, anthracite or briquette. When the non-caking coal is used, no slag breaking turntable (8) is provided in the gasifier.

6. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak-shaving method according to claim 1, characterized in that: The source of oxygen required for the production of water gas is the oxygen produced as a by-product of the water electrolysis hydrogen production device, or the oxygen produced by air separation oxygen production.

7. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak-shaving method according to claim 1, characterized in that: The height-to-diameter ratio of the gasification bed in the hydrogen-coal gas section is 2.0-4; the height-to-diameter ratio of the gasification bed in the hydrogen-coal gas section is inversely proportional to the gasification activity of the raw coal, a smaller height-to-diameter ratio is used for high-activity coal, and a larger height-to-diameter ratio is used for low-activity coal. The inner diameter of the gasifier is 1.2-2 meters, or 2.2-4 meters, or 4.2-6 meters; the inner cylinder of the furnace body of the hydrogen-coal gas section is a frustum with a smaller upper part and a larger lower part; the working pressure is 3-5MPa, or 5.1-8MPa.

8. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method according to claim 1, characterized in that: The particle size of raw coal or briquette coal is 3-10mm, or 11-40mm, or 41-80mm.

9. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method according to claim 1, characterized in that: 0-15% water vapor is added to the hydrogen gasification agent entering each hydrogenation gasification layer of the hydrogen gas section to prevent the hydrogenation gasification layer from overheating; the cooling water of the pressure shell jacket of the hydrogen gas section and the cooling water of the pressure shell jacket of the water gas section are circulated separately.

10. A low-carbon coal-based polygeneration LNG energy storage NGCC power generation peak shaving method according to claim 1, characterized in that: The highest temperature of the water-gas section is the dry slag gasification method with a temperature below the ash melting point, or the slag gasification method with a temperature above the ash melting point.

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