Zero-carbon glass kiln process

Abstract

The invention discloses a zero-carbon glass kiln process. A system required by the process comprises a photovoltaic power generation device, an air separation device, a water electrolysis hydrogen production device, a mixer, a methanation device, a waste heat boiler I, a reforming device, a glass kiln, a waste heat boiler II and a dust removal and desulfurization device. Green oxygen, green nitrogen and green hydrogen are produced through green electricity driving; the flue gas of the glass kiln is cyclically enriched into high-concentration carbon dioxide (95.0 v% or above), the high-concentration carbon dioxide and green hydrogen are subjected to a methanation reaction to produce methane, and the methane, the carbon dioxide and water vapor are subjected to a reforming reaction to produce carbon monoxide and hydrogen; carbon monoxide and hydrogen are used as fuel of the glass kiln, green oxygen and carbon dioxide are mixed to form carbon-based oxygen-enriched combustion which is used as a combustion improver of the glass kiln, carbon-based oxygen-enriched combustion of the glass kiln is carried out, and redundant carbon dioxide is sold. According to the invention, the purposes of greenness, energy conservation, almost no nitrogen oxide and zero carbon are realized.

Description

Technical Field

[0001] The present invention relates to the technical field of glass furnaces, and in particular to a zero-carbon glass furnace process. Background Art

[0002] Greenhouse gas emissions are the main factor causing global warming, among which the greenhouse effect produced by carbon dioxide accounts for more than 70v% of all greenhouse gases. Therefore, the reduction of carbon dioxide emissions is an urgent issue to be addressed and is crucial to controlling the greenhouse effect and mitigating global warming.

[0003] At present, the flue gas from domestic glass kilns is basically discharged directly into the atmosphere. Although the glass industry accounts for a small proportion of carbon emissions, it is a high-energy consumption and high-emission industry, and the CO2 emission situation is not optimistic. Summary of the invention

[0004] The purpose of the present invention is to provide a zero-carbon glass kiln process to solve the deficiencies of the prior art.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A zero-carbon glass kiln process, wherein the systems required for the process include a photovoltaic power generation device, an air separation device, a water electrolysis hydrogen production device, a mixer, a methanation device, a waste heat boiler I, a reforming device, a glass kiln, a waste heat boiler II and a dust removal and desulfurization device;

[0007] Photovoltaic power generation device, used to produce green electricity, to provide power to the air separation unit and water electrolysis hydrogen production unit;

[0008] air separation units for the production of oxygen and nitrogen;

[0009] Water electrolysis hydrogen production device for producing hydrogen and oxygen;

[0010] A mixer is used to mix the oxygen sent from the air separation unit, the oxygen sent from the water electrolysis hydrogen production unit and the circulating flue gas sent from the glass furnace into carbon-based enriched oxygen;

[0011] A methanation device, used for methanation reaction of hydrogen sent from the water electrolysis hydrogen production device and circulating flue gas sent from the dust removal and desulfurization device;

[0012] Waste heat boiler I is used to recover the waste heat of methane (including saturated water vapor) sent from the methanation device and produce steam as a by-product;

[0013] Reforming device, used for methane reforming reaction between methane (containing saturated water vapor) sent from waste heat boiler I and part of the circulating flue gas sent from the glass furnace;

[0014] The glass furnace uses carbon monoxide and hydrogen sent from the reforming unit as fuel and carbon-based rich oxygen sent from the mixer as combustion aid to produce glass liquid;

[0015] Waste heat boiler II is used to recover the waste heat of circulating flue gas sent from the glass kiln and produce steam as a by-product;

[0016] The dust removal and desulfurization device is used to remove dust and desulfurize the circulating flue gas sent from the waste heat boiler II;

[0017] The photovoltaic power generation device is connected to the air separation device and the water electrolysis hydrogen production device respectively; the nitrogen outlet of the air separation device is connected to the tin tank of the glass kiln and the nitrogen product storage tank respectively, and a pressure reducing valve is provided on the connecting pipe between the nitrogen outlet of the air separation device and the tin tank of the glass kiln; the oxygen outlet of the air separation device and the oxygen outlet of the water electrolysis hydrogen production device are both connected to the mixer, and a pressure reducing valve is provided on the connecting pipe between the oxygen outlet of the water electrolysis hydrogen production device and the mixer, and a flow detector, a temperature detector and a pressure measuring instrument are provided on the connecting pipe between the oxygen outlet of the air separation device, the oxygen outlet of the water electrolysis hydrogen production device and the mixer detector, pressure detector, oxygen purity detector, flow regulating valve; the hydrogen outlet of the water electrolysis hydrogen production device is connected to the methanation device; the carbon-based oxygen-rich outlet of the mixer is switched and connected to the heat storage grid A / B of the glass kiln and then connected to the glass kiln; the methane outlet of the methanation device is connected to the waste heat boiler I; the methane outlet of the waste heat boiler I is switched and connected to the heat storage grid A / B of the reforming device and then connected to the reforming device, a pressure reducing valve is provided on the connecting pipeline between the methane outlet of the waste heat boiler I and the heat storage grid A / B of the reforming device, and the steam outlet of the waste heat boiler I and the steam utilization device The carbon monoxide + hydrogen outlet of the reforming device is connected to the glass kiln; the circulating flue gas outlet of the glass kiln is respectively connected to the heat storage grid B / A of the glass kiln and then connected to the waste heat boiler II and the mixer, and the heat storage grid A / B of the reforming device is switched and connected to the reforming device, and the heat storage grid B / A of the reforming device is switched and connected to the dust removal and desulfurization device. A booster is provided on the connecting pipe between the heat storage grid B / A of the glass kiln and the waste heat boiler II and the mixer, and a flow detector, a temperature detector and a flow meter are provided on the connecting pipe between the heat storage grid B / A of the glass kiln and the mixer. The heat storage grid A / B of the glass kiln and the reforming device, and the heat storage grid B / A of the reforming device are connected with a supercharger, and the heat storage grid B / A of the reforming device are connected with a pressure reducing valve; the circulating flue gas outlet of the waste heat boiler II is connected with the dust removal and desulfurization device; the circulating flue gas outlet of the dust removal and desulfurization device is connected with the methanation device and the CO2 product storage tank respectively, and the circulating flue gas outlet of the dust removal and desulfurization device and the connecting pipe of the methanation device are provided with a supercharger;

[0018] The process comprises the following steps:

[0019] (1) The photovoltaic power generation device produces green electricity to provide power for the air separation device and the water electrolysis hydrogen production device; the air separation device uses the green electricity provided by the photovoltaic power generation device as power to produce oxygen and nitrogen, and the oxygen is sent to the mixer. The nitrogen is partially decompressed and sent to the tin bath of the glass kiln as a protective gas, and the rest is sold outside; the water electrolysis hydrogen production device uses the green electricity provided by the photovoltaic power generation device as power to produce hydrogen and oxygen, and the hydrogen is sent to the methanation device, and the oxygen is decompressed and sent to the mixer;

[0020] (2) The mixer mixes the oxygen sent from the air separation unit and the water electrolysis unit and the circulating flue gas sent from the glass kiln into carbon-based enriched oxygen as a combustion aid for the glass kiln;

[0021] (3) The methanation device reacts the hydrogen sent from the water electrolysis hydrogen production device with the circulating flue gas sent from the dust removal and desulfurization device to produce methane (containing saturated water vapor) to send the generated methane to the waste heat boiler I;

[0022] (4) Waste heat boiler I recovers the waste heat of methane (including saturated water vapor) sent from the methanation unit and produces steam as a by-product; the steam is sold externally, and the methane (including saturated water vapor) after waste heat recovery is decompressed and sent to the reforming unit;

[0023] (5) The reforming device conducts a methane reforming reaction with the methane (containing saturated water vapor) sent from the waste heat boiler I and part of the circulating flue gas sent from the glass kiln; the circulating flue gas sent from the glass kiln enters the reforming device in two ways, one way enters the heat storage grid on one side of the reforming device to provide heat for the heat storage grid, and the heat storage grid provides heat for the raw gas of the reforming device in the next round. After the heat exchange, the circulating flue gas is depressurized and sent to the dust removal and desulfurization device; the other way and the methane (containing saturated water vapor) sent from the waste heat boiler I are sent to the heat storage grid on the other side of the reforming device. The heat storage grid has been heated by the circulating flue gas in the previous round. The heat storage grids on both sides work in rotation and are heated by the heat of the heat storage grid. Under the action of a certain pressure and a certain catalyst, methane, carbon dioxide and water vapor undergo a methane reforming reaction in the reaction bed of the reforming device to generate carbon monoxide and hydrogen, which are sent to the glass kiln as fuel;

[0024] (6) The glass furnace uses carbon monoxide and hydrogen sent from the reforming device as fuel and carbon-based rich oxygen sent from the mixer as a combustion aid to produce glass liquid; the carbon-based rich oxygen sent from the mixer first passes through a heat storage grid on one side of the glass furnace, which has been heated by the previous round of circulating flue gas. The heat storage grids on both sides work in rotation and are sent into the glass furnace after being heated to a certain temperature;

[0025] After a certain period of circulation and enrichment, the carbon dioxide concentration of the flue gas from the glass kiln reaches equilibrium; the circulating flue gas is divided into two paths, one of which passes through the heat storage grid on the other side of the glass kiln to provide heat for the heat storage grid, and the next round of the heat storage grid provides heat for the carbon-based enriched oxygen sent from the mixer. After heat exchange, the circulating flue gas on this path is pressurized and sent to the mixer and waste heat boiler II; the other path does not pass through the heat storage grid of the glass kiln, and is pressurized and sent to the reforming device;

[0026] (7) Waste heat boiler II recovers the waste heat of the circulating flue gas sent from the glass kiln and produces steam as a by-product; the steam is sold externally, and the circulating flue gas after waste heat recovery is sent to the dust removal and desulfurization device;

[0027] (8) The dust removal and desulfurization device removes dust and desulfurizes the circulating flue gas sent from the waste heat boiler II; after dust removal and desulfurization, part of the circulating flue gas is pressurized and sent to the methanation device, and the rest is cooled and sold as a carbon dioxide product;

[0028] In the initial stage, the glass kiln uses natural gas as fuel and air as a combustion aid. After flue gas is generated, the carbon-based enriched oxygen mixed with the flue gas and oxygen produced by the air separation unit and the water electrolysis hydrogen production unit gradually replaces the air for combustion. After a certain period of circulation enrichment, the carbon dioxide concentration in the circulating flue gas reaches equilibrium, the methanation unit, reforming unit, waste heat boiler I, waste heat boiler II, and dust removal and desulfurization unit are all put into use, and the system enters normal operation.

[0029] Furthermore, the oxygen produced by the air separation unit in step (1) has a purity of 99.6% by volume or more, is at room temperature and has a pressure of 0.2-0.3 MPa, and is sent to a mixer; the nitrogen produced has a purity of 99.9% by volume or more, is at room temperature and has a pressure of 0.2-0.3 MPa, and part of the nitrogen is decompressed to 0.05 MPa and sent to the tin bath of the glass furnace as a protective gas, and the rest is sold outside;

[0030] The purity of hydrogen produced by the water electrolysis hydrogen production device is above 99.8v%, the temperature is 90-100°C, and the pressure is 2.5-3.0MPa. The hydrogen is sent to the methanation device; the purity of oxygen produced is above 99.0v%, the temperature is 90-100°C, and the pressure is 2.5-3.0MPa. The oxygen is decompressed to 0.2-0.3MPa and then sent to the mixer.

[0031] Furthermore, in step (2), the oxygen sent from the air separation device has a purity of 99.6v% or more, is at room temperature, and has a pressure of 0.2-0.3MPa; the oxygen sent from the water electrolysis device has a purity of 99.0v% or more, is at a temperature of 90-100°C, and has a pressure of 0.2-0.3MPa; the carbon dioxide concentration of the circulating flue gas sent from the glass kiln is 95.0v% or more, is at a temperature of 550-650°C, and has a pressure of 0.15-0.25MPa; the flow rates of the oxygen sent from the air separation device, the oxygen sent from the water electrolysis hydrogen production device, and the circulating flue gas sent from the glass kiln are respectively adjusted by regulating valves, and the mixed carbon-based oxygen-enriched oxygen has a content of 21-30v%, a temperature of 460-480°C, and a pressure of 0.05-0.10MPa. The oxygen concentration is adjusted according to the requirements of different glass kilns.

[0032] Furthermore, in step (3), the purity of hydrogen sent from the water electrolysis hydrogen production device is 99.8v% or more, the temperature is 90-100°C, and the pressure is 2.5-3.0MPa. The carbon dioxide concentration of the circulating flue gas sent from the dust removal and desulfurization device is 95.0v% or more, the temperature is 250-300°C, and the pressure is 2.5-3.0MPa. The two are sent to the methanation device at a volume ratio of H2:CO2=4:1. Under the action of the methanation nickel-based catalyst, hydrogen and carbon dioxide are catalytically converted to generate methane, and a large amount of heat is released at the same time. The purity of the generated methane is above 94.0v% (calculated as dry gas), the temperature is 390-410°C, and the pressure is 2.5-3.0MPa. The methane (including saturated water vapor) is sent to the waste heat boiler I.

[0033] Furthermore, in step (4), the temperature of the methane (including saturated water vapor) delivered from the methanation device is 390-410°C. After the waste heat is recovered by the waste heat boiler I, the temperature is reduced to 240-260°C, and 1.5 MPa steam is produced as a by-product for external sale. The methane (including saturated water vapor) after the waste heat is recovered is depressurized to 0.5-1.0 MPa and then delivered to the reforming device.

[0034] Furthermore, in step (5), the methane (including saturated water vapor) sent from the waste heat boiler I has a methane purity of more than 94.0v% (calculated as dry gas), a temperature of 240-260°C, and a pressure of 0.5-1.0MPa, and the circulating flue gas sent from the glass furnace has a carbon dioxide concentration of more than 95.0v%, a temperature of 1300-1400°C, and a pressure of 0.5-1.0MPa; the circulating flue gas sent from the glass furnace enters the reforming device in two ways, one of which enters the heat storage grid on one side of the reforming device to provide heat for the heat storage grid, and the next round of the heat storage grid provides heat for the raw gas of the reforming device. After heat exchange, the circulating flue gas temperature is reduced to 250-300°C, and the pressure is reduced to 0.1-0.2 MPa and then sent to the dust removal and desulfurization device; the other route and the methane (including saturated water vapor) sent by the waste heat boiler I are sent to the heat storage grid on the other side of the reforming device at the ratio of CH4:CO2 volume ratio = 2:1. The heat storage grid has been heated by the previous round of circulating flue gas. The heat storage grids on both sides work in rotation and are heated to 900-1000℃ by the heat of the heat storage grid. In the reaction bed of the reforming device at a pressure of 0.5-1.0MPa and the action of nickel-based catalyst, methane, carbon dioxide and water vapor undergo methane reforming reaction to generate carbon monoxide and hydrogen. The volume ratio of CO:H2 is about 3:5, the outlet temperature is 700-800℃, and the pressure is 0.5-1.0MPa, which is sent to the glass kiln as fuel.

[0035] Furthermore, in step (6), the carbon monoxide and hydrogen sent from the reforming device have a volume ratio of CO:H2 of about 3:5, a temperature of 700-800°C, and a pressure of 0.5-1.0 MPa, and the carbon-based oxygen-enriched oxygen sent from the mixer has an oxygen content of 21-30v%, a temperature of 460-480°C, and a pressure of 0.05-0.10 MPa; the carbon-based oxygen-enriched oxygen sent from the mixer first passes through a heat storage grid on one side of the glass furnace, which has been heated by the circulating flue gas of the previous round, and the heat storage grids on both sides work in rotation and are sent to the glass furnace after being heated to 700-800°C; the volume ratio of fuel: combustion aid is about 1:2; in the glass furnace, carbon monoxide and hydrogen undergo a combustion reaction under the combustion aid of carbon-based oxygen, providing heat for the glass furnace to produce glass liquid;

[0036] After 3 to 5 hours of circulation and enrichment, the flue gas from the glass kiln reaches a balance in carbon dioxide concentration, which is above 95.0v%, with a temperature of 1300 to 1400°C and a pressure of 0.01 to 0.05MPa; the circulating flue gas is divided into two paths, one of which passes through the heat storage grid on the other side of the glass kiln to provide heat for the heat storage grid, and in the next round, the heat storage grid provides heat for the carbon-based oxygen-enriched gas sent from the mixer. After heat exchange, the circulating flue gas is cooled to 550 to 650°C, and the pressure is increased to 0.15 to 0.25MPa, and is sent to the mixer and waste heat boiler II; the other path does not pass through the heat storage grid of the glass kiln, the temperature is 1300 to 1400°C, the pressure is increased to 0.5 to 1.0MPa, and is sent to the reforming device.

[0037] Furthermore, the circulating flue gas sent from the glass kiln in step (7) has a carbon dioxide concentration of more than 95.0v%, a temperature of 550-650°C, and a pressure of 0.15-0.25MPa. After the waste heat is recovered by the waste heat boiler II, the temperature is reduced to 250-300°C, the pressure is 0.1-0.2MPa, and 1.5-4.0MPa of steam is produced as a by-product for external sale; the circulating flue gas after waste heat recovery is sent to the dust removal and desulfurization device.

[0038] Furthermore, the dust removal and desulfurization device is composed of two parts, one is a high-temperature dust collector, and the other is a dry desulfurization device; the high-temperature dust collector uses cyclone separation to remove dust, and the dry desulfurization equipment uses zinc oxide for desulfurization;

[0039] In step (8), the circulating flue gas first passes through a high-temperature dust collector in the dust removal and desulfurization device to remove dust, and then passes through a dry desulfurization equipment in the dust removal and desulfurization device to remove hydrogen sulfide; the circulating flue gas sent from the waste heat boiler II has a carbon dioxide concentration of more than 95.0v%, a temperature of 250-300°C, and a pressure of 0.1-0.2MPa. The circulating flue gas after dust removal and desulfurization has a carbon dioxide concentration of more than 95.0v%, a temperature of 250-300°C, and a pressure of 0.05-0.10MPa. Part of it is pressurized to 2.5-3.0MPa and sent to the methanation device, and the rest is cooled and sold as a carbon dioxide product.

[0040] Furthermore, in the initial stage, the glass kiln uses natural gas as fuel and air as a combustion aid. After flue gas is generated, the carbon-based enriched oxygen mixed with the flue gas and oxygen produced by the air separation unit and the water electrolysis hydrogen production unit gradually replaces the air for combustion. After 3 to 5 hours of circulation enrichment, the carbon dioxide concentration in the circulating flue gas reaches equilibrium, and the carbon dioxide concentration is above 95.0v%. The methanation unit, reforming unit, waste heat boiler I, waste heat boiler II, and dust removal and desulfurization unit are all put into use, and the system enters normal operation.

[0041] Beneficial effects of the present invention:

[0042] 1. The present invention uses green electricity to drive an air separation device to produce green oxygen and green nitrogen, and drives a water electrolysis hydrogen production device to produce green hydrogen and green oxygen; the flue gas of the glass kiln is circulated to enrich high-concentration carbon dioxide (95.0v% or more), which is methanated with green hydrogen to produce methane, and methane is reformed with carbon dioxide and water vapor to produce carbon monoxide and hydrogen; carbon monoxide and hydrogen are used as fuel for the glass kiln, and green oxygen and carbon dioxide are mixed into carbon-based enriched oxygen as a combustion aid for the glass kiln, and carbon-based oxygen-enriched combustion is carried out in the glass kiln, and excess carbon dioxide is sold. The present invention achieves the purpose of being green, energy-saving, almost free of nitrogen oxides, and zero carbon.

[0043] 2. The present invention uses green electricity produced by a photovoltaic power generation device to drive an air separation device to produce green oxygen and green nitrogen, and uses green electricity produced by a photovoltaic power generation device to drive a water electrolysis hydrogen production device to produce green hydrogen and green oxygen, which is green and environmentally friendly.

[0044] 3. The flue gas of the glass kiln of the present invention is circulated and enriched into carbon dioxide with a concentration of more than 95.0v%, which is used as a raw material for methanation, a raw material for reforming, and a raw material for carbon-based oxygen-enriched combustion in the glass kiln. The excess carbon dioxide is sold as a product, truly achieving a zero-carbon glass kiln.

[0045] 4. The present invention uses green hydrogen produced by a water electrolysis hydrogen production device and high-concentration carbon dioxide (95.0v% or more) enriched in flue gas as raw materials for methanation to produce methane, thereby utilizing waste carbon dioxide and improving the utilization rate of waste resources.

[0046] 5. The present invention uses methane produced by a methanation device, high-concentration carbon dioxide (95.0v% or more) enriched in flue gas, and water vapor as raw materials to produce carbon monoxide and hydrogen through reforming reaction, thereby increasing the calorific value of the fuel and reducing fuel consumption.

[0047] 6. The present invention uses high-concentration carbon dioxide (95.0v% or more) enriched in flue gas to replace air for carbon-based oxygen-enriched combustion, which can produce almost no nitrogen oxides during the combustion process. At the same time, because carbon dioxide is a greenhouse gas, the thermal efficiency of the glass kiln is improved.

[0048] 7. The flue gas of the present invention is enriched into high-concentration carbon dioxide (95.0v% or more), which creates conditions for low-cost carbon dioxide capture and creates possibilities for zero-carbon glass furnaces.

[0049] 8. The present invention combines methanation and reforming with a glass kiln, making full use of the heat of the flue gas of the glass kiln for heat exchange with the raw gas, thereby improving heat utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 This is a schematic diagram of the system structure required for the zero-carbon glass kiln process of the present invention. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0052] A zero-carbon glass kiln process, the system required for the process is as follows Figure 1 As shown, it includes a photovoltaic power generation device, an air separation device, a water electrolysis hydrogen production device, a mixer, a methanation device, a waste heat boiler I, a reforming device, a glass kiln, a waste heat boiler II and a dust removal and desulfurization device.

[0053] Photovoltaic power generation devices are used to produce green electricity (green electricity) to provide power to air separation devices and water electrolysis hydrogen production devices. The main principle of photovoltaic power generation is the photoelectric effect of semiconductors. Under the irradiation of electromagnetic waves with a frequency higher than a certain frequency (this frequency is called the limit frequency), the electrons inside certain substances absorb energy and escape to form current, which is photoelectricity. Photovoltaic power generation has the advantages of being safe and reliable, noise-free, pollution-free, absolutely clean and pollution-free.

[0054] The air separation unit uses the green electricity provided by the photovoltaic power generation device as electrical energy to produce oxygen and nitrogen. The air separation unit produces oxygen and nitrogen by first compressing and cooling the air and liquefying it. The different boiling points of the oxygen and nitrogen components are used to make the gas and liquid contact on the distillation tower plate to exchange mass and heat. The high-boiling-point oxygen component is continuously condensed from the steam into liquid, and the low-boiling-point nitrogen component is continuously transferred into the steam, so that the nitrogen content in the rising steam is continuously increased, and the oxygen content in the downstream liquid is getting higher and higher, thereby separating oxygen and nitrogen. The oxygen purity produced by the air separation unit is above 99.6v%, at room temperature and pressure of 0.2-0.3MPa, and the nitrogen purity produced is above 99.9v%, at room temperature and pressure of 0.2-0.3MPa. Because the air separation unit uses the green electricity produced by the photovoltaic power generation device as electrical energy, the oxygen produced is green oxygen and the nitrogen produced is green nitrogen. The oxygen produced by the air separation unit is sent to the mixer, the oxygen sent by the water electrolysis hydrogen production unit, and the circulating flue gas sent by the glass kiln (the carbon dioxide concentration is above 95.0v%) to mix into carbon-based rich oxygen for combustion in the glass kiln. The nitrogen produced by the air separation unit is partially decompressed to 0.05MPa and then sent to the tin bath of the glass kiln as protective gas, and the rest is sold outside.

[0055] The water electrolysis hydrogen production device uses the green electricity provided by the photovoltaic power generation device as electrical energy to produce hydrogen and oxygen. Water electrolysis hydrogen production is a relatively convenient method for producing hydrogen. Direct current is passed into the electrolytic cell filled with electrolyte, and water molecules undergo electrochemical reactions on the electrodes and decompose into nitrogen and oxygen. The hydrogen produced by the water electrolysis hydrogen production device has a purity of more than 99.8v%, a temperature of 90-100°C, and a pressure of 2.5-3.0MPa. The oxygen produced has a purity of more than 99.0v%, a temperature of 90-100°C, and a pressure of 2.5-3.0MPa. Because the water electrolysis hydrogen production device uses the green electricity produced by the photovoltaic power generation device as electrical energy, the hydrogen produced is green hydrogen and the oxygen produced is green oxygen. The hydrogen produced by the water electrolysis hydrogen production device is sent to the methanation device for methanation reaction. The oxygen produced by the water electrolysis hydrogen production device is depressurized to 0.2-0.3MPa and sent to the mixer. The oxygen sent from the air separation device and the circulating flue gas (carbon dioxide concentration is above 95.0v%) sent from the glass kiln are mixed into carbon-based rich oxygen as a combustion aid for the glass kiln combustion.

[0056] Hydrogen production reaction equation by water electrolysis: 2H2O→2H2+O2

[0057] The mixer is used to mix the oxygen sent from the air separation unit, the oxygen sent from the water electrolysis hydrogen production unit and the circulating flue gas sent from the glass kiln into carbon-based rich oxygen as a combustion aid for the glass kiln combustion. The oxygen sent from the air separation unit has a purity of more than 99.6v%, room temperature, and a pressure of 0.2-0.3MPa. The oxygen sent from the water electrolysis hydrogen production unit has a purity of more than 99.0v%, a temperature of 90-100℃, and a pressure of 0.2-0.3MPa. The carbon dioxide concentration of the circulating flue gas sent from the glass kiln is more than 95.0v%, a temperature of 550-650℃, and a pressure of 0.15-0.25MPa. The oxygen sent from the air separation unit, the oxygen sent from the water electrolysis hydrogen production unit, and the circulating flue gas sent from the glass kiln are respectively adjusted through regulating valves and then mixed into a carbon-based oxygen-enriched gas with an oxygen content of 21-30v%, a temperature of 460-480℃, and a pressure of 0.05-0.10MPa for use as a combustion aid for the glass kiln. The oxygen concentration is adjusted according to the requirements of different glass kilns.

[0058] The methanation device is used to methanate the hydrogen sent from the water electrolysis hydrogen production device and the circulating flue gas sent from the dust removal and desulfurization device. The purity of the hydrogen sent from the water electrolysis hydrogen production device is above 99.8v%, the temperature is 90-100℃, and the pressure is 2.5-3.0MPa. The carbon dioxide concentration of the circulating flue gas sent from the dust removal and desulfurization device is above 95.0v%, the temperature is 250-300℃, and the pressure is 2.5-3.0MPa. The two are sent to the methanation device at a volume ratio of H2:CO2 = 4:1. Under the action of the methanation nickel-based catalyst, hydrogen and carbon dioxide are catalytically converted to methane, and a large amount of heat is released at the same time. The purity of the generated methane is above 94.0v% (calculated as dry gas), the temperature is 390-410℃, and the pressure is 2.5-3.0MPa. Methane (including saturated water vapor) is sent to the waste heat boiler I.

[0059] Methanation reaction equation: 4H2+CO2→CH4+2H2O

[0060] Waste heat boiler I is used to recover the waste heat of methane (including saturated water vapor) sent from the methanation unit and produce steam as a by-product. The temperature of methane (including saturated water vapor) sent from the methanation unit is 390-410°C. After the waste heat is recovered by waste heat boiler I, the temperature is reduced to 240-260°C, and 1.5MPa steam is produced as a by-product for external sale. Because the more suitable pressure for the reforming reaction is 0.5-1.0MPa, the methane (including saturated water vapor) after waste heat recovery is decompressed to 0.5-1.0MPa and then sent to the reforming unit.

[0061] The reforming device is used for methane reforming reaction between methane (containing saturated water vapor) sent from waste heat boiler I and part of the circulating flue gas sent from the glass furnace. The methane purity of methane (containing saturated water vapor) sent from waste heat boiler I is above 94.0v% (calculated as dry gas), the temperature is 240-260℃, and the pressure is 0.5-1.0MPa. The carbon dioxide concentration of the circulating flue gas sent from the glass furnace is above 95.0v%, the temperature is 1300-1400℃, and the pressure is 0.5-1.0MPa. The circulating flue gas sent from the glass kiln enters the reforming device in two ways. One way enters the heat storage grid on one side of the reforming device to provide heat for the heat storage grid. In the next round, the heat storage grid provides heat for the raw gas of the reforming device. After heat exchange, the circulating flue gas temperature is reduced to 250-300°C, and the pressure is reduced to 0.1-0.2MPa before being sent to the dust removal and desulfurization device; the other way and the methane (including saturated water vapor) sent from the waste heat boiler I are sent to the heat storage grid on the other side of the reforming device at a volume ratio of CH4:CO2 = 2:1. The heat storage grid (the heat storage grid has been heated by the previous round of circulating flue gas, and the heat storage grids on both sides work in rotation) is heated to 900-1000°C by the heat of the heat storage grid. In the reaction bed of the reforming device at a pressure of 0.5-1.0MPa and the action of nickel-based catalyst, methane, carbon dioxide and water vapor undergo methane reforming reaction to generate carbon monoxide and hydrogen, with a volume ratio of CO:H2 of about 3:5, and an outlet temperature of 700-800°C and a pressure of 0.5-1.0MPa, which is sent to the glass kiln as fuel.

[0062] Reforming reaction equation: CH4+H2O→CO+3H2

[0063] CH4+CO2→2CO+2H2

[0064] The glass furnace uses carbon monoxide and hydrogen sent from the reforming device as fuel (natural gas is used as fuel in the initial stage of production) and carbon-based enriched oxygen sent from the mixer as a combustion aid to produce glass liquid. The carbon monoxide and hydrogen sent from the reforming device have a volume ratio of CO:H2 of about 3:5, a temperature of 700-800°C, and a pressure of 0.5-1.0MPa. The carbon-based enriched oxygen sent from the mixer has an oxygen content of 21-30v%, a temperature of 460-480°C, and a pressure of 0.05-0.10MPa. The carbon-based enriched oxygen sent from the mixer first passes through the heat storage grid on one side of the glass furnace (the heat storage grid has been heated by the previous round of circulating flue gas, and the heat storage grids on both sides work in rotation), and is heated to 700-800°C before being sent to the glass furnace. The volume ratio of fuel (carbon monoxide and hydrogen sent from the reforming device): combustion aid (carbon-based enriched oxygen sent from the mixer) is about 1:2. In the glass kiln, carbon monoxide and hydrogen react with the help of carbon-based oxygen-rich combustion to provide heat for the glass kiln to produce molten glass.

[0065] Carbon-based oxygen-rich combustion reaction equation: 2CO+O2+CO2→3CO2

[0066] 2H2+O2+CO2→2H2O+CO2

[0067] After 3 to 5 hours of circulation and enrichment, the flue gas of the glass furnace reaches a balance of carbon dioxide concentration, with a carbon dioxide concentration of more than 95.0v%, a temperature of 1300 to 1400℃, and a pressure of 0.01 to 0.05MPa. The circulating flue gas is divided into two paths. One path passes through the heat storage grid on the other side of the glass furnace to provide heat for the heat storage grid. In the next round, the heat storage grid provides heat for the carbon-based oxygen-enriched gas sent from the mixer. After heat exchange, the circulating flue gas of this path is cooled to 550 to 650℃, and the pressure is increased to 0.15 to 0.25MPa, and sent to the mixer and waste heat boiler II; the other path does not pass through the heat storage grid of the glass furnace, the temperature is 1300 to 1400℃, the pressure is increased to 0.5 to 1.0MPa, and sent to the reforming device.

[0068] Waste heat boiler II is used to recover the waste heat of the circulating flue gas sent from the glass kiln and produce steam as a by-product. The circulating flue gas sent from the glass kiln has a carbon dioxide concentration of more than 95.0v%, a temperature of 550-650℃, and a pressure of 0.15-0.25MPa. After the waste heat is recovered by the waste heat boiler II, the temperature is reduced to 250-300℃, the pressure is 0.1-0.2MPa, and 1.5-4.0MPa of steam is produced as a by-product for external sale. The circulating flue gas after waste heat recovery is sent to the dust removal and desulfurization device.

[0069] The dust removal and desulfurization device is used to remove dust and desulfurize the circulating flue gas sent from the waste heat boiler II. The dust removal and desulfurization device consists of two parts, one is a high-temperature dust collector, and the other is a dry desulfurization device. The high-temperature dust collector uses cyclone separation for dust removal, and the dry desulfurization equipment uses zinc oxide for desulfurization. The circulating flue gas first passes through the high-temperature dust collector to remove dust, and then passes through the dry desulfurization equipment to remove hydrogen sulfide. The carbon dioxide concentration of the circulating flue gas sent from the waste heat boiler II is above 95.0v%, the temperature is 250-300℃, and the pressure is 0.1-0.2MPa. The circulating flue gas after dust removal and desulfurization has a carbon dioxide concentration of above 95.0v%, a temperature of 250-300℃, and a pressure of 0.05-0.10MPa. Part of it is pressurized to 2.5-3.0MPa and sent to the methanation device, and the rest is cooled and sold as a carbon dioxide product.

[0070] Dry desulfurization reaction equation: ZnO+H2S→ZnS+H2O

[0071] The photovoltaic power generation device is connected to the air separation device and the water electrolysis hydrogen production device respectively; the nitrogen outlet of the air separation device is connected to the tin tank of the glass kiln and the nitrogen product storage tank respectively, and a pressure reducing valve is provided on the connecting pipe between the nitrogen outlet of the air separation device and the tin tank of the glass kiln; the oxygen outlet of the air separation device and the oxygen outlet of the water electrolysis hydrogen production device are both connected to the mixer, and a pressure reducing valve is provided on the connecting pipe between the oxygen outlet of the water electrolysis hydrogen production device and the mixer, and a flow detector F, a temperature detector T, and a pressure detector P are provided on the connecting pipe between the oxygen outlet of the air separation device, the oxygen outlet of the water electrolysis hydrogen production device, and the mixer , gas (oxygen) purity detector C, flow control valve FIC; the hydrogen outlet of the water electrolysis hydrogen production device is connected to the methanation device; the carbon-based oxygen-rich outlet of the mixer is switched and connected to the heat storage grid A / B of the glass kiln and then connected to the glass kiln; the methane outlet of the methanation device is connected to the waste heat boiler I; the methane outlet of the waste heat boiler I is switched and connected to the heat storage grid A / B of the reforming device and then connected to the reforming device, a pressure reducing valve is provided on the connecting pipeline between the methane outlet of the waste heat boiler I and the heat storage grid A / B of the reforming device, and the steam outlet of the waste heat boiler I is connected to the steam utilization device; the carbon monoxide +

[0072] The hydrogen outlet is connected to the glass kiln; the circulating flue gas outlet of the glass kiln is respectively connected to the heat storage grid B / A of the glass kiln and then connected to the waste heat boiler II and the mixer, and is connected to the heat storage grid A / B of the reforming device and then connected to the reforming device, and is connected to the heat storage grid B / A of the reforming device and then connected to the dust removal and desulfurization device. A booster is provided on the connecting pipeline between the heat storage grid B / A of the glass kiln and the waste heat boiler II and the mixer, and a flow detector F, a temperature detector T, and a pressure detector are provided on the connecting pipeline between the heat storage grid B / A of the glass kiln and the mixer. P, gas (carbon dioxide) purity detector C, flow regulating valve FIC, a booster is provided on the connecting pipes between the glass kiln and the heat storage grid A / B of the reforming unit, and the heat storage grid B / A of the reforming unit, a pressure reducing valve is provided on the connecting pipe between the heat storage grid B / A of the reforming unit and the dust removal and desulfurization unit; the circulating flue gas outlet of the waste heat boiler II is connected to the dust removal and desulfurization unit; the circulating flue gas outlet of the dust removal and desulfurization unit is respectively connected to the methanation unit and the CO2 product storage tank, and a booster is provided on the connecting pipe between the circulating flue gas outlet of the dust removal and desulfurization unit and the methanation unit.

[0073] The process comprises the following steps:

[0074] (1) The photovoltaic power generation device produces green electricity to provide power to the air separation device and the water electrolysis hydrogen production device. The air separation device uses the green electricity provided by the photovoltaic power generation device as power to produce oxygen and nitrogen, and the oxygen purity is 99.6v%

[0075] The oxygen is sent to the mixer when the purity of nitrogen is above 99.9v%, the temperature is 0.2-0.3MPa, and the pressure is 0.2-0.3MPa. Part of the nitrogen is decompressed to 0.05MPa and sent to the tin bath of the glass kiln as a protective gas, and the rest is sold outside. The water electrolysis hydrogen production device uses the green electricity provided by the photovoltaic power generation device as electricity to produce hydrogen and oxygen. The hydrogen purity is above 99.8v%, the temperature is 90-100℃, and the pressure is 2.5-3.0MPa. The hydrogen is sent to the methanation device; the oxygen purity is above 99.0v%, the temperature is 90-100℃, and the pressure is 2.5-

[0076] 3.0MPa, the oxygen is depressurized to 0.2-0.3MPa and then sent to the mixer.

[0077] (2) The mixer mixes the oxygen sent from the air separation unit and the water electrolysis unit and the circulating flue gas sent from the glass kiln into carbon-based rich oxygen as a combustion aid for the glass kiln. The oxygen sent from the air separation unit has a purity of more than 99.6v%, room temperature, and a pressure of 0.2-0.3MPa. The oxygen sent from the water electrolysis unit has a purity of more than 99.0v%, a temperature of 90-100°C, and a pressure of 0.2-0.3MPa. The carbon dioxide concentration of the circulating flue gas sent from the glass kiln is more than 95.0v%, a temperature of 550-650°C, and a pressure of 0.15-0.25MPa. The oxygen sent from the air separation unit, the oxygen sent from the water electrolysis hydrogen production unit, and the circulating flue gas sent from the glass kiln are respectively adjusted in flow through regulating valves. The mixed carbon-based oxygen-enriched oxygen has a content of 21-30v%, a temperature of 460-480℃, and a pressure of 0.05-0.10MPa. The oxygen concentration is adjusted according to the requirements of different glass kilns.

[0078] (3) The methanation device reacts the hydrogen sent from the water electrolysis hydrogen production device with the circulating flue gas sent from the dust removal and desulfurization device. The purity of the hydrogen sent from the water electrolysis hydrogen production device is above 99.8v%, the temperature is 90-100°C, and the pressure is 2.5-3.0MPa. The carbon dioxide concentration of the circulating flue gas sent from the dust removal and desulfurization device is above 95.0v%, the temperature is 250-300°C, and the pressure is 2.5-3.0MPa. The two are sent to the methanation device at a volume ratio of H2:CO2 = 4:1. Under the action of the methanation nickel-based catalyst, hydrogen and carbon dioxide are catalytically converted to methane, and a large amount of heat is released at the same time. The purity of the generated methane is above 94.0v% (calculated as dry gas), the temperature is 390-410°C, and the pressure is 2.5-3.0MPa. The methane (including saturated water vapor) is sent to the waste heat boiler I.

[0079] (4) Waste heat boiler I recovers the waste heat of methane (including saturated water vapor) sent from the methanation unit and produces steam as a by-product. The temperature of methane (including saturated water vapor) sent from the methanation unit is 390-410°C. After the waste heat is recovered by waste heat boiler I, the temperature is reduced to 240-260°C, and 1.5MPa steam is produced as a by-product for external sale. The methane (including saturated water vapor) after waste heat recovery is depressurized to 0.5-1.0MPa and sent to the reforming unit.

[0080] (5) The reforming device reforms the methane (containing saturated water vapor) sent from the waste heat boiler I and part of the circulating flue gas sent from the glass kiln. The methane purity of the methane (containing saturated water vapor) sent from the waste heat boiler I is above 94.0v% (calculated as dry gas), the temperature is 240-260°C, and the pressure is 0.5-1.0MPa. The carbon dioxide concentration of the circulating flue gas sent from the glass kiln is above 95.0v%, the temperature is 1300-1400°C, and the pressure is 0.5-1.0MPa. The circulating flue gas sent from the glass kiln enters the reforming device in two ways. One way enters the heat storage grid on one side of the reforming device to provide heat for the heat storage grid. In the next round, the heat storage grid provides heat for the raw gas of the reforming device. After heat exchange, the circulating flue gas temperature is reduced to 250-300°C, and the pressure is reduced to 0.1-0.2MPa before being sent to the dust removal and desulfurization device; the other way and the methane (including saturated water vapor) sent from the waste heat boiler I are sent to the heat storage grid on the other side of the reforming device at a volume ratio of CH4:CO2 = 2:1. The heat storage grid (the heat storage grid has been heated by the previous round of circulating flue gas, and the heat storage grids on both sides work in rotation) is heated to 900-1000°C by the heat of the heat storage grid. In the reaction bed of the reforming device at a pressure of 0.5-1.0MPa and the action of nickel-based catalyst, methane, carbon dioxide and water vapor undergo methane reforming reaction to generate carbon monoxide and hydrogen, with a volume ratio of CO:H2 of about 3:5, and an outlet temperature of 700-800°C and a pressure of 0.5-1.0MPa, which is sent to the glass kiln as fuel.

[0081] (6) The glass furnace uses carbon monoxide and hydrogen sent from the reforming device as fuel (natural gas is used as fuel in the initial stage of production) and carbon-based enriched oxygen sent from the mixer as a combustion aid to produce glass liquid. The carbon monoxide and hydrogen sent from the reforming device have a volume ratio of CO:H2 of about 3:5, a temperature of 700-800°C, and a pressure of 0.5-1.0MPa. The carbon-based enriched oxygen sent from the mixer has an oxygen content of 21-30v%, a temperature of 460-480°C, and a pressure of 0.05-0.10MPa. The carbon-based enriched oxygen sent from the mixer first passes through the heat storage grid on one side of the glass furnace (the heat storage grid has been heated by the previous round of circulating flue gas, and the heat storage grids on both sides work in rotation), and is heated to 700-800°C before being sent to the glass furnace. The volume ratio of fuel (carbon monoxide and hydrogen sent from the reforming device): combustion aid (carbon-based enriched oxygen sent from the mixer) is about 1:2. In the glass kiln, carbon monoxide and hydrogen react with the help of carbon-based oxygen-rich combustion to provide heat for the glass kiln to produce molten glass.

[0082] After 3 to 5 hours of circulation and enrichment, the flue gas of the glass furnace reaches a balance of carbon dioxide concentration, with a carbon dioxide concentration of more than 95.0v%, a temperature of 1300 to 1400℃, and a pressure of 0.01 to 0.05MPa. The circulating flue gas is divided into two paths. One path passes through the heat storage grid on the other side of the glass furnace to provide heat for the heat storage grid. In the next round, the heat storage grid provides heat for the carbon-based oxygen-enriched gas sent from the mixer. After heat exchange, the circulating flue gas of this path is cooled to 550 to 650℃, and the pressure is increased to 0.15 to 0.25MPa, and sent to the mixer and waste heat boiler II; the other path does not pass through the heat storage grid of the glass furnace, the temperature is 1300 to 1400℃, the pressure is increased to 0.5 to 1.0MPa, and sent to the reforming device.

[0083] (7) Waste heat boiler II recovers the waste heat of the circulating flue gas sent from the glass kiln and produces steam as a by-product. The circulating flue gas sent from the glass kiln has a carbon dioxide concentration of more than 95.0v%, a temperature of 550-650°C, and a pressure of 0.15-0.25MPa. After the waste heat is recovered by waste heat boiler II, the temperature is reduced to 250-300°C, the pressure is 0.1-0.2MPa, and 1.5-4.0MPa of steam is produced as a by-product for external sale. The circulating flue gas after waste heat recovery is sent to the dust removal and desulfurization device.

[0084] (8) The dust removal and desulfurization device removes dust and desulfurizes the circulating flue gas sent from the waste heat boiler II. The circulating flue gas first passes through the high-temperature dust collector in the dust removal and desulfurization device to remove dust, and then passes through the dry desulfurization equipment in the dust removal and desulfurization device to remove hydrogen sulfide. The carbon dioxide concentration of the circulating flue gas sent from the waste heat boiler II is above 95.0v%, the temperature is 250-300℃, and the pressure is 0.1-0.2MPa. The circulating flue gas after dust removal and desulfurization has a carbon dioxide concentration of above 95.0v%, a temperature of 250-300℃, and a pressure of 0.05-0.10MPa. Part of it is pressurized to 2.5-3.0MPa and sent to the methanation device, and the rest is cooled and sold as a carbon dioxide product.

[0085] In the initial stage, the glass kiln uses natural gas as fuel and air as a combustion aid. After flue gas is generated, the carbon-based enriched oxygen mixed with flue gas and oxygen (produced by air separation unit and water electrolysis hydrogen production unit) gradually replaces the air for combustion. After 3 to 5 hours of circulation enrichment, the carbon dioxide concentration in the circulating flue gas reaches equilibrium, and the carbon dioxide concentration is above 95.0v%. The methanation unit, reforming unit, waste heat boiler I, waste heat boiler II, and dust removal and desulfurization unit are all put into use, and the system enters normal operating state.

Claims

1. A zero-carbon glass kiln process, characterized in that: The systems required for the process include a photovoltaic power generation device, an air separation device, a water electrolysis hydrogen production device, a mixer, a methanation device, a waste heat boiler I, a reforming device, a glass kiln, a waste heat boiler II and a dust removal and desulfurization device; Photovoltaic power generation device, used to produce green electricity, to provide power to the air separation unit and water electrolysis hydrogen production unit; air separation units for the production of oxygen and nitrogen; Water electrolysis hydrogen production device for producing hydrogen and oxygen; A mixer is used to mix the oxygen sent from the air separation unit, the oxygen sent from the water electrolysis hydrogen production unit and the circulating flue gas sent from the glass furnace into carbon-based enriched oxygen; A methanation device, used for methanation reaction of hydrogen sent from the water electrolysis hydrogen production device and circulating flue gas sent from the dust removal and desulfurization device; Waste heat boiler I is used to recover the waste heat of methane (including saturated water vapor) sent from the methanation device and produce steam as a by-product; Reforming device, used for methane reforming reaction between methane (containing saturated water vapor) sent from waste heat boiler I and part of the circulating flue gas sent from the glass furnace; The glass furnace uses carbon monoxide and hydrogen sent from the reforming unit as fuel and carbon-based rich oxygen sent from the mixer as combustion aid to produce glass liquid; Waste heat boiler II is used to recover the waste heat of circulating flue gas sent from the glass kiln and produce steam as a by-product; The dust removal and desulfurization device is used to remove dust and desulfurize the circulating flue gas sent from the waste heat boiler II; The photovoltaic power generation device is connected to the air separation device and the water electrolysis hydrogen production device respectively; the nitrogen outlet of the air separation device is connected to the tin tank of the glass kiln and the nitrogen product storage tank respectively, and a pressure reducing valve is provided on the connecting pipe between the nitrogen outlet of the air separation device and the tin tank of the glass kiln; the oxygen outlet of the air separation device and the oxygen outlet of the water electrolysis hydrogen production device are both connected to the mixer, and a pressure reducing valve is provided on the connecting pipe between the oxygen outlet of the water electrolysis hydrogen production device and the mixer, and a flow detector, a temperature detector and a pressure measuring instrument are provided on the connecting pipe between the oxygen outlet of the air separation device, the oxygen outlet of the water electrolysis hydrogen production device and the mixer detector, pressure detector, oxygen purity detector, flow regulating valve; the hydrogen outlet of the water electrolysis hydrogen production device is connected to the methanation device; the carbon-based oxygen-rich outlet of the mixer is switched and connected to the heat storage grid A / B of the glass kiln and then connected to the glass kiln; the methane outlet of the methanation device is connected to the waste heat boiler I; the methane outlet of the waste heat boiler I is switched and connected to the heat storage grid A / B of the reforming device and then connected to the reforming device, a pressure reducing valve is provided on the connecting pipeline between the methane outlet of the waste heat boiler I and the heat storage grid A / B of the reforming device, and the steam outlet of the waste heat boiler I and the steam utilization device The carbon monoxide + hydrogen outlet of the reforming device is connected to the glass kiln; the circulating flue gas outlet of the glass kiln is respectively connected to the heat storage grid B / A of the glass kiln and then connected to the waste heat boiler II and the mixer, and the heat storage grid A / B of the reforming device is switched and connected to the reforming device, and the heat storage grid B / A of the reforming device is switched and connected to the dust removal and desulfurization device. A booster is provided on the connecting pipe between the heat storage grid B / A of the glass kiln and the waste heat boiler II and the mixer, and a flow detector, a temperature detector and a flow meter are provided on the connecting pipe between the heat storage grid B / A of the glass kiln and the mixer. The heat storage grid A / B of the glass kiln and the reforming device, and the heat storage grid B / A of the reforming device are connected with a supercharger, and the heat storage grid B / A of the reforming device are connected with a pressure reducing valve; the circulating flue gas outlet of the waste heat boiler II is connected with the dust removal and desulfurization device; the circulating flue gas outlet of the dust removal and desulfurization device is connected with the methanation device and the CO2 product storage tank respectively, and the circulating flue gas outlet of the dust removal and desulfurization device and the connecting pipe of the methanation device are provided with a supercharger; The process comprises the following steps: (1) The photovoltaic power generation device produces green electricity to provide power for the air separation device and the water electrolysis hydrogen production device; the air separation device uses the green electricity provided by the photovoltaic power generation device as power to produce oxygen and nitrogen, and the oxygen is sent to the mixer. The nitrogen is partially decompressed and sent to the tin bath of the glass kiln as a protective gas, and the rest is sold outside; the water electrolysis hydrogen production device uses the green electricity provided by the photovoltaic power generation device as power to produce hydrogen and oxygen, and the hydrogen is sent to the methanation device, and the oxygen is decompressed and sent to the mixer; (2) The mixer mixes the oxygen sent from the air separation unit and the water electrolysis unit and the circulating flue gas sent from the glass kiln into carbon-based enriched oxygen as a combustion aid for the glass kiln; (3) The methanation device reacts the hydrogen sent from the water electrolysis hydrogen production device with the circulating flue gas sent from the dust removal and desulfurization device to produce methane (containing saturated water vapor) to send the generated methane to the waste heat boiler I; (4) Waste heat boiler I recovers the waste heat of methane (including saturated water vapor) sent from the methanation unit and produces steam as a by-product; the steam is sold externally, and the methane (including saturated water vapor) after waste heat recovery is decompressed and sent to the reforming unit; (5) The reforming device conducts a methane reforming reaction with the methane (containing saturated water vapor) sent from the waste heat boiler I and part of the circulating flue gas sent from the glass kiln; the circulating flue gas sent from the glass kiln enters the reforming device in two ways, one way enters the heat storage grid on one side of the reforming device to provide heat for the heat storage grid, and the heat storage grid provides heat for the raw gas of the reforming device in the next round. After the heat exchange, the circulating flue gas is depressurized and sent to the dust removal and desulfurization device; the other way and the methane (containing saturated water vapor) sent from the waste heat boiler I are sent to the heat storage grid on the other side of the reforming device. The heat storage grid has been heated by the circulating flue gas in the previous round. The heat storage grids on both sides work in rotation and are heated by the heat of the heat storage grid. Under the action of a certain pressure and a certain catalyst, methane, carbon dioxide and water vapor undergo a methane reforming reaction in the reaction bed of the reforming device to generate carbon monoxide and hydrogen, which are sent to the glass kiln as fuel; (6) The glass furnace uses carbon monoxide and hydrogen sent from the reforming device as fuel and carbon-based rich oxygen sent from the mixer as a combustion aid to produce glass liquid; the carbon-based rich oxygen sent from the mixer first passes through a heat storage grid on one side of the glass furnace, which has been heated by the previous round of circulating flue gas. The heat storage grids on both sides work in rotation and are sent into the glass furnace after being heated to a certain temperature; After a certain period of circulation and enrichment, the carbon dioxide concentration of the flue gas from the glass kiln reaches equilibrium; the circulating flue gas is divided into two paths, one of which passes through the heat storage grid on the other side of the glass kiln to provide heat for the heat storage grid, and the next round of the heat storage grid provides heat for the carbon-based enriched oxygen sent from the mixer. After heat exchange, the circulating flue gas on this path is pressurized and sent to the mixer and waste heat boiler II; the other path does not pass through the heat storage grid of the glass kiln, and is pressurized and sent to the reforming device; (7) Waste heat boiler II recovers the waste heat of circulating flue gas sent from the glass kiln and produces steam as a by-product; Steam is sold externally, and the circulating flue gas after waste heat recovery is sent to the dust removal and desulfurization device; (8) The dust removal and desulfurization device removes dust and desulfurizes the circulating flue gas sent from the waste heat boiler II; after dust removal and desulfurization, part of the circulating flue gas is pressurized and sent to the methanation device, and the rest is cooled and sold as a carbon dioxide product; In the initial stage, the glass kiln uses natural gas as fuel and air as a combustion aid. After flue gas is generated, the carbon-based enriched oxygen mixed with the flue gas and oxygen produced by the air separation unit and the water electrolysis hydrogen production unit gradually replaces the air for combustion. After a certain period of circulation enrichment, the carbon dioxide concentration in the circulating flue gas reaches equilibrium, the methanation unit, reforming unit, waste heat boiler I, waste heat boiler II, and dust removal and desulfurization unit are all put into use, and the system enters normal operation.

2. A zero-carbon glass kiln process according to claim 1, characterized in that: Step (1) The oxygen produced by the air separation unit has a purity of 99.6% by volume or more, is at room temperature and has a pressure of 0.2-0.3 MPa, and is sent to a mixer; the nitrogen produced has a purity of 99.9% by volume or more, is at room temperature and has a pressure of 0.2-0.3 MPa, and part of the nitrogen is decompressed to 0.05 MPa and sent to the tin bath of the glass kiln as a protective gas, and the rest is sold outside; The purity of hydrogen produced by the water electrolysis hydrogen production device is above 99.8v%, the temperature is 90-100°C, and the pressure is 2.5-3.0MPa. The hydrogen is sent to the methanation device; the purity of oxygen produced is above 99.0v%, the temperature is 90-100°C, and the pressure is 2.5-3.0MPa. The oxygen is decompressed to 0.2-0.3MPa and then sent to the mixer.

3. A zero-carbon glass kiln process according to claim 1, characterized in that: In step (2), the oxygen sent from the air separation unit has a purity of 99.6v% or more, is at room temperature, and has a pressure of 0.2-0.3MPa; the oxygen sent from the water electrolysis unit has a purity of 99.0v% or more, is at a temperature of 90-100°C, and has a pressure of 0.2-0.3MPa; the carbon dioxide concentration of the circulating flue gas sent from the glass kiln is 95.0v% or more, is at a temperature of 550-650°C, and has a pressure of 0.15-0.25MPa; the flow rates of the oxygen sent from the air separation unit, the oxygen sent from the water electrolysis hydrogen production unit, and the circulating flue gas sent from the glass kiln are respectively adjusted by regulating valves, and the mixed carbon-based oxygen-enriched oxygen has a content of 21-30v%, a temperature of 460-480°C, and a pressure of 0.05-0.10MPa. The oxygen concentration is adjusted according to the requirements of different glass kilns.

4. A zero-carbon glass kiln process according to claim 1, characterized in that: In step (3), the purity of hydrogen sent from the water electrolysis hydrogen production device is 99.8v% or more, the temperature is 90-100°C, and the pressure is 2.5-3.0MPa. The carbon dioxide concentration of the circulating flue gas sent from the dust removal and desulfurization device is 95.0v% or more, the temperature is 250-300°C, and the pressure is 2.5-3.0MPa. The two are sent to the methanation device at a volume ratio of H2:CO2=4:

1. Under the action of the methanation nickel-based catalyst, hydrogen and carbon dioxide are catalytically converted to generate methane, and a large amount of heat is released at the same time. The purity of the generated methane is above 94.0v% (calculated as dry gas), the temperature is 390-410°C, and the pressure is 2.5-3.0MPa. The methane (including saturated water vapor) is sent to the waste heat boiler I.

5. A zero-carbon glass kiln process according to claim 1, characterized in that: In step (4), the temperature of the methane (including saturated water vapor) sent from the methanation device is 390-410°C. After the waste heat is recovered by the waste heat boiler I, the temperature is reduced to 240-260°C, and 1.5 MPa steam is produced as a by-product for external sale. The methane (including saturated water vapor) after the waste heat is recovered is depressurized to 0.5-1.0 MPa and sent to the reforming device.

6. A zero-carbon glass kiln process according to claim 1, characterized in that: Step (5) The methane (including saturated water vapor) sent from the waste heat boiler I has a methane purity of more than 94.0v% (calculated as dry gas), a temperature of 240-260°C, and a pressure of 0.5-1.0MPa. The circulating flue gas sent from the glass furnace has a carbon dioxide concentration of more than 95.0v%, a temperature of 1300-1400°C, and a pressure of 0.5-1.0MPa. The circulating flue gas sent from the glass furnace enters the reforming device in two ways, one of which enters the heat storage grid on one side of the reforming device to provide heat for the heat storage grid. In the next round, the heat storage grid provides heat for the raw gas of the reforming device. After heat exchange, the temperature of the circulating flue gas is reduced to 250-300°C, and the pressure is reduced to 0.1-0.2MPa. Then it is sent to the dust removal and desulfurization device; the methane (including saturated water vapor) sent by the other route and waste heat boiler I is sent to the heat storage grid on the other side of the reforming device at the ratio of CH4:CO2 volume ratio of 2:

1. The heat storage grid has been heated by the previous round of circulating flue gas. The heat storage grids on both sides work in rotation and are heated to 900-1000℃ by the heat of the heat storage grid. In the reaction bed of the reforming device at a pressure of 0.5-1.0MPa and the action of nickel-based catalyst, methane, carbon dioxide and water vapor undergo methane reforming reaction to generate carbon monoxide and hydrogen. The volume ratio of CO:H2 is about 3:5, the outlet temperature is 700-800℃, and the pressure is 0.5-1.0MPa, which is sent to the glass kiln as fuel.

7. A zero-carbon glass kiln process according to claim 1, characterized in that: Step (6) The carbon monoxide and hydrogen sent from the reforming device have a volume ratio of CO:H2 of about 3:5, a temperature of 700-800°C, and a pressure of 0.5-1.0 MPa. The carbon-based oxygen-enriched gas sent from the mixer has an oxygen content of 21-30v%, a temperature of 460-480°C, and a pressure of 0.05-0.10 MPa. The carbon-based oxygen-enriched gas sent from the mixer first passes through a heat storage grid on one side of the glass furnace, which has been heated by the circulating flue gas of the previous round. The heat storage grids on both sides work in rotation and are sent to the glass furnace after being heated to 700-800°C. The volume ratio of fuel: combustion aid is about 1:

2. In the glass furnace, carbon monoxide and hydrogen undergo a combustion reaction under the combustion aid of the carbon-based oxygen-enriched gas, thereby providing heat for the glass furnace to produce glass liquid. After 3 to 5 hours of circulation and enrichment, the flue gas from the glass kiln reaches a balance in carbon dioxide concentration, which is above 95.0v%, with a temperature of 1300 to 1400°C and a pressure of 0.01 to 0.05MPa; the circulating flue gas is divided into two paths, one of which passes through the heat storage grid on the other side of the glass kiln to provide heat for the heat storage grid, and in the next round, the heat storage grid provides heat for the carbon-based oxygen-enriched gas sent from the mixer. After heat exchange, the circulating flue gas is cooled to 550 to 650°C, and the pressure is increased to 0.15 to 0.25MPa, and is sent to the mixer and waste heat boiler II; the other path does not pass through the heat storage grid of the glass kiln, the temperature is 1300 to 1400°C, the pressure is increased to 0.5 to 1.0MPa, and is sent to the reforming device.

8. A zero-carbon glass kiln process according to claim 1, characterized in that: In step (7), the circulating flue gas sent from the glass kiln has a carbon dioxide concentration of more than 95.0v%, a temperature of 550-650°C, and a pressure of 0.15-0.25MPa. After the waste heat is recovered by the waste heat boiler II, the temperature is reduced to 250-300°C, the pressure is 0.1-0.2MPa, and 1.5-4.0MPa of steam is produced as a by-product for external sale; the circulating flue gas after waste heat recovery is sent to the dust removal and desulfurization device.

9. A zero-carbon glass kiln process according to claim 1, characterized in that: The dust removal and desulfurization device is composed of two parts, one is a high-temperature dust collector, and the other is a dry desulfurization equipment; The high-temperature dust collector uses cyclone separation for dust removal, and the dry desulfurization equipment uses zinc oxide for desulfurization; In step (8), the circulating flue gas first passes through a high-temperature dust collector in the dust removal and desulfurization device to remove dust, and then passes through a dry desulfurization equipment in the dust removal and desulfurization device to remove hydrogen sulfide; the circulating flue gas sent from the waste heat boiler II has a carbon dioxide concentration of more than 95.0v%, a temperature of 250-300°C, and a pressure of 0.1-0.2MPa. The circulating flue gas after dust removal and desulfurization has a carbon dioxide concentration of more than 95.0v%, a temperature of 250-300°C, and a pressure of 0.05-0.10MPa. Part of it is pressurized to 2.5-3.0MPa and sent to the methanation device, and the rest is cooled and sold as a carbon dioxide product.

10. A zero-carbon glass kiln process according to claim 1, characterized in that: In the initial stage, the glass kiln uses natural gas as fuel and air as a combustion aid. After flue gas is generated, the carbon-based enriched oxygen mixed with the flue gas and oxygen produced by the air separation unit and the water electrolysis hydrogen production unit gradually replaces the air for combustion. After 3 to 5 hours of circulation enrichment, the carbon dioxide concentration in the circulating flue gas reaches equilibrium, and the carbon dioxide concentration is above 95.0v%. The methanation unit, reforming unit, waste heat boiler I, waste heat boiler II, and dust removal and desulfurization unit are all put into use, and the system enters normal operation.

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