Combustion technology of a glass furnace with a non-catalytic conversion furnace

Abstract

Combustion method for a glass furnace with a non-catalytic conversion furnace, wherein the system required for combustion comprises a glass furnace, a non-catalytic conversion furnace A, a non-catalytic conversion furnace B, a flue gas recovery device, a chimney, a high-temperature flue gas fan, a natural gas supply device and an oxygen supply device; wherein the non-catalytic conversion furnace A and the non-catalytic conversion furnace B are arranged on two sides of the glass furnace and connected to the glass furnace; wherein the non-catalytic conversion furnace A and the non-catalytic conversion furnace B are switchably connected to an inlet of the flue gas recovery device and an outlet of the flue gas recovery device is each connected to the chimney and the high-temperature flue gas fan, the high-temperature flue gas fan being connected to the bottom of the non-catalytic conversion furnace A and the bottom of the non-catalytic conversion furnace B; wherein the natural gas supply device is switchably connected to the bottom of the non-catalytic conversion furnace A, the upper part of the non-catalytic conversion furnace A, the bottom of the non-catalytic conversion furnace B, the upper part of the non-catalytic conversion furnace B and the glass furnace, the oxygen supply device is connected to the glass furnace; wherein an oxygen content analyzer, a flow meter, a temperature sensor and a pressure sensor are provided on a pipe through which the high-temperature flue gas fan is connected to the bottom of the non-catalytic conversion furnace A and the bottom of the non-catalytic conversion furnace B, wherein a flow control valve and a pressure sensor are provided on a pipe through which the natural gas supply device is connected to the bottom of the non-catalytic conversion furnace A, the upper part of the non-catalytic conversion furnace A, the bottom of the non-catalytic conversion furnace B, the upper part of the non-catalytic conversion furnace B and the glass furnace, and wherein a flow control valve and the pressure sensor are provided on a pipe through which the oxygen supply device is connected to the glass furnace; the combustion process includes the following steps: 1) In the initial phase, combustion is promoted by means of air, and after the generation of the flue gas, the circulating flue gas is mixed with oxygen and used as a combustion improver to gradually replace the promotion of combustion with air, whereby after a certain time of the cycle the circulating flue gas contains high levels of water vapor and carbon dioxide, and the circulating flue gas and the oxygen completely replace the promotion of combustion with air, at which point the system enters its normal operating state; 2) Conversion and Reforming Phase: When the oxygen content in the circulating flue gas is less than or equal to a set limit, the circulating flue gas enters the furnace from the bottom of the non-catalytic conversion furnace A, and natural gas also enters the furnace from the bottom of the non-catalytic conversion furnace A, whereby the natural gas undergoes a conversion and reforming reaction with water vapor and carbon dioxide in the circulating flue gas, producing hydrogen and carbon monoxide, namely high-calorific-value water gas, which are fed into the glass furnace, whereby oxygen is fed into the glass furnace and undergoes a combustion reaction with carbon monoxide and hydrogen produced by non-catalytic conversion and a small amount of natural gas that does not undergo a conversion and reforming reaction;wherein the circulating flue gas, when the oxygen content in the circulating flue gas is greater than the set limit, enters the furnace from the bottom of the non-catalytic conversion furnace A, and natural gas enters the furnace from the upper part of the non-catalytic conversion furnace A, wherein natural gas undergoes a conversion and a reforming reaction with water vapor and carbon dioxide in the circulating flue gas, thereby producing hydrogen and carbon monoxide, namely high-calorific-value water gas, which are fed into the glass furnace, wherein oxygen is fed into the glass furnace and undergoes a combustion reaction in the glass furnace with carbon monoxide and hydrogen produced by non-catalytic conversion and a small amount of natural gas that does not undergo a conversion and reforming reaction; ; 3) Flue gas purging phase: After completion of the conversion and reforming phase, the natural gas is fed directly into the glass furnace and the circulating flue gas enters the furnace from the bottom of the non-catalytic conversion furnace A to purge, replace and convert the remaining combustible gas, and enters the glass furnace, with oxygen being fed into the glass furnace to undergo a combustion reaction; 4) Heating phase of the conversion furnace: In the conversion and reforming phase and the flue gas purging phase, high-temperature flue gas from the outlet of the glass furnace enters the non-catalytic conversion furnace B to heat the furnace and store heat, and then enters the flue gas recovery device to recover heat and be dedusted and desulfurized, after which part is pressurized by the high-temperature flue gas fan and then introduced into the circulation of the non-catalytic conversion furnace A, while the remainder is discharged through the chimney or undergoes a CCUS process; 5) After a certain time, the non-catalytic conversion furnace A / B is switched over, that is, a conversion and a reforming reaction take place in the non-catalytic conversion furnace B, and the non-catalytic conversion furnace A heats up and heat is stored there; such a switching is repeated cyclically.

Description

AREA OF INVENTION

[0001] The invention relates to the technical field of glass furnace combustion and in particular to a combustion process for a glass furnace with a non-catalytic conversion furnace. STATE OF THE ART

[0002] WO 2011 / 152 024 A1 describes a process in which a feed gas containing methane and water vapor is introduced into heat storage chambers where the exhaust gas is held. Since the methane and water vapor in the feed gas are previously mixed in gas mixing chambers, the methane concentration in the feed gas is standardized before it is introduced into the heat storage chambers. The feed gas is reformed in the heat storage chambers and then combusted in a melt bath by reaction with oxygen or air, producing a glass melt in the melt bath. The heat storage chambers alternately perform the functions of introducing, heating, and reforming the feed gas, as well as recovering heat from the exhaust gas.

[0003] EP 0 643 013 A1 describes a process in which hot exhaust gases from an oxygen-based hydrocarbon combustion process of furnace A, consisting mainly of water vapor and carbon dioxide, are used to reform a hydrocarbon-containing substance in reformer C, in the presence or absence of oxygen to produce carbon monoxide and hydrogen.

[0004] DE 691 14 056 T2 describes a process for oxygen-enriched furnaces for glass melting or glass production with reforming of the fuel and an integrated treatment of the heat and process flows, in particular the use of commercially available pure oxygen in a furnace for glass production with the recovery of heat from the exhaust gas by at least partially reforming the furnace fuel, wherein the exhaust gas is predominantly carbon dioxide due to the oxygen purity, and wherein the carbon dioxide can be recovered for recirculation and for release as a product.

[0005] CN 1 01 337 762 A describes a method for remixing hot exhaust gases in a glass melting furnace. The remixing mechanism for hot exhaust gases is opened after the glass melting furnace has reached a stable production state. At this point, the two remixing lines operate alternately, so that the hot exhaust gases in each line enter the opposite bypass channel and mix there with the combustion air entering the bypass channel.

[0006] Since global warming affects various aspects such as environmental security, water resource security, and food security, it has exacerbated the risk of extreme climate disasters and seriously threatens the human environment. Greenhouse gas emissions are the most significant driver of global warming. Carbon dioxide accounts for more than 70% of all greenhouse gases, making carbon dioxide reduction a pressing issue crucial for controlling the greenhouse effect and slowing global warming.

[0007] With the imbalance in global energy supply and the intensification of the geopolitical crisis, fuel prices continue to rise, glass production costs are increasing, and at the same time, companies face ever greater demands for energy conservation and emission reduction. Air-assisted combustion is used in the analysis and investigation of existing combustion systems. In this process, nitrogen is unnecessarily heated and released into the atmosphere at high temperatures, resulting in significant heat loss. Furthermore, nitrogen reacts with oxygen at high temperatures, producing NOₓ. x is generated, and NO x -Gas is released into the atmosphere, which slightly forms acid rain and causes environmental pollution.

[0008] In the present invention, a final treatment is transformed into a source treatment, reducing carbon dioxide emissions and achieving a fundamental breakthrough in extremely low nitrogen oxide emissions. REVELATION OF THE INVENTION

[0009] One object of the present invention is to provide a combustion process for a glass furnace with a non-catalytic conversion furnace in order to overcome the disadvantages of the prior art.

[0010] According to the present invention, the problem is solved by the following embodiment: A combustion method for a glass furnace with a non-catalytic conversion furnace, wherein the system required for combustion comprises a glass furnace, a non-catalytic conversion furnace A, a non-catalytic conversion furnace B, a flue gas recovery device, a chimney, a high-temperature flue gas fan, a natural gas supply device and an oxygen supply device; wherein the non-catalytic conversion furnace A and the non-catalytic conversion furnace B are arranged on two sides of the glass furnace and connected to the glass furnace; wherein the non-catalytic conversion furnace A and the non-catalytic conversion furnace B are switchably connected to an inlet of the flue gas recovery device and an outlet of the flue gas recovery device is each connected to the chimney and the high-temperature flue gas fan, the high-temperature flue gas fan being connected to the bottom of the non-catalytic conversion furnace A and the bottom of the non-catalytic conversion furnace B; wherein the natural gas supply device is switchably connected to the bottom of the non-catalytic conversion furnace A, the upper part of the non-catalytic conversion furnace A, the bottom of the non-catalytic conversion furnace B, the upper part of the non-catalytic conversion furnace B and the glass furnace, the oxygen supply device is connected to the glass furnace; wherein an oxygen content analyzer, a flow meter, a temperature sensor and a pressure sensor are provided on a pipe through which the high-temperature flue gas fan is connected to the bottom of the non-catalytic conversion furnace A and the bottom of the non-catalytic conversion furnace B, wherein a flow control valve and a pressure sensor are provided on a pipe through which the natural gas supply device is connected to the bottom of the non-catalytic conversion furnace A, the upper part of the non-catalytic conversion furnace A, the bottom of the non-catalytic conversion furnace B, the upper part of the non-catalytic conversion furnace B and the glass furnace, and wherein a flow control valve and the pressure sensor are provided on a pipe through which the oxygen supply device is connected to the glass furnace; the combustion process includes the following steps: 1) In the initial phase, combustion is promoted by means of air, and after the generation of the flue gas, the circulating flue gas is mixed with oxygen and used as a combustion improver to gradually replace the promotion of combustion with air, whereby after a certain time of the cycle the circulating flue gas contains high levels of water vapor and carbon dioxide, and the circulating flue gas and the oxygen completely replace the promotion of combustion with air, at which point the system enters its normal operating state; 2) Conversion and Reforming Phase: When the oxygen content in the circulating flue gas is less than or equal to a set limit, the circulating flue gas enters the furnace from the bottom of the non-catalytic conversion furnace A, and natural gas also enters the furnace from the bottom of the non-catalytic conversion furnace A, whereby the natural gas undergoes a conversion and reforming reaction with water vapor and carbon dioxide in the circulating flue gas, producing hydrogen and carbon monoxide, namely high-calorific-value water gas, which are fed into the glass furnace, whereby oxygen is fed into the glass furnace and undergoes a combustion reaction with carbon monoxide and hydrogen produced by non-catalytic conversion and a small amount of natural gas that does not undergo a conversion and reforming reaction;wherein the circulating flue gas, when the oxygen content in the circulating flue gas is greater than the set content limit, enters the furnace from the bottom of the non-catalytic conversion furnace A and natural gas enters the furnace from the upper part of the non-catalytic conversion furnace A, wherein natural gas undergoes a conversion and a reforming reaction with water vapor and carbon dioxide in the circulating flue gas, thereby producing hydrogen and carbon monoxide, namely water gas with a high calorific value, and feeding it into the glass furnace, wherein oxygen is fed into the glass furnace and undergoes a combustion reaction in the glass furnace with carbon monoxide and hydrogen produced by non-catalytic conversion and a small amount of natural gas that does not undergo a conversion and reforming reaction; 3) Flue gas purging phase: After completion of the conversion and reforming phase, the natural gas is fed directly into the glass furnace and the circulating flue gas enters the furnace from the bottom of the non-catalytic conversion furnace A to purge, replace and convert the remaining combustible gas, and enters the glass furnace, with oxygen being fed into the glass furnace to undergo a combustion reaction; 4) Heating phase of the conversion furnace: In the conversion and reforming phase and the flue gas purging phase, high-temperature flue gas from the outlet of the glass furnace enters the non-catalytic conversion furnace B to heat the furnace and store heat, and then enters the flue gas recovery device to recover heat and be dedusted and desulfurized, after which part is pressurized by the high-temperature flue gas fan and then introduced into the circulation of the non-catalytic conversion furnace A, while the remainder is discharged through the chimney or undergoes a CCUS process; 5) After a certain time, the non-catalytic conversion furnace A / B is switched over, that is, a conversion and a reforming reaction take place in the non-catalytic conversion furnace B, and the non-catalytic conversion furnace A heats up and heat is stored there; such a switching process is repeated cyclically.

[0011] Furthermore, it is provided that the oxygen supply device produces oxygen by means of a deep-freeze process or a pressure swing adsorption process with an oxygen purity of ≥ 90% and a pressure of 0.05 to 0.2 MPa.

[0012] Furthermore, it is provided that in step 1) in the initial phase, air is used to promote combustion and air enters the glass furnace through the non-catalytic conversion furnace A, while natural gas enters the glass furnace directly, in which air and natural gas are burned, the flue gas produced by the combustion flowing through the non-catalytic conversion furnace B to heat it and store heat there, then entering the flue gas recovery device to recover heat and be dedusted and desulfurized, after which it is introduced via the high-temperature flue gas fan into the non-catalytic conversion furnace A and then enters the glass furnace, with oxygen also being introduced into the glass furnace at the same time.to replace the need for air-assisted combustion with a mixture of circulating flue gas and oxygen; wherein, after a while, the non-catalytic conversion furnace A / B is switched over and air enters the glass furnace through the non-catalytic conversion furnace B, while natural gas enters the glass furnace directly, wherein air and natural gas are combusted in a glass furnace and the flue gas produced by the combustion flows through the non-catalytic conversion furnace A to heat the non-catalytic conversion furnace A and store heat there, then enters the flue gas recovery device to recover heat and be dedusted and desulfurized, is then introduced via the high-temperature flue gas fan into the non-catalytic conversion furnace B and then enters the glass furnace, with oxygen being introduced into the glass furnace at the same time.to promote combustion by means of a mixture of circulating flue gas and oxygen and to gradually replace the promotion of combustion with air, whereby such a switching is repeated cyclically; wherein after a certain time of the cycle the circulating flue gas contains a high content of water vapor and carbon dioxide and the circulating flue gas and oxygen completely replace the promotion of combustion with air, whereby the system enters its normal operating state.

[0013] Furthermore, it is planned that in steps 2) to 5) the non-catalytic conversion furnace A / B is switched every 20 minutes, with the conversion and reforming phase taking place from 0 to 17 minutes, the flue gas purging phase taking place from 18 to 20 minutes and the heating phase of the conversion furnace taking place from 0 to 20 minutes.

[0014] Furthermore, it is stipulated that the oxygen content limit in the circulating flue gas is set to 2% in step 2).

[0015] Furthermore, it is provided that in step 2) natural gas from the upper area of ​​the non-catalytic conversion furnace A enters the furnace, namely from a position at a distance of 1 / 5 to 1 / 3 from the top of the non-catalytic conversion furnace A, when the oxygen content in the circulating flue gas is greater than the set content limit.

[0016] Furthermore, it is planned that in steps 2), 3) and 5) oxygen will be fed into the glass furnace via an oxygen spray gun.

[0017] Furthermore, it is provided that after heat recovery, dust removal and desulfurization in step 4), the circulating flue gas is subjected to a pressure of 0.05 to 0.2 MPa by the high-temperature flue gas fan and then introduced into the non-catalytic conversion furnace A for recirculation.

[0018] Furthermore, it is provided that the system required for combustion also includes an intelligent control system for controlling the switching of the non-catalytic conversion furnace A / B, for controlling the switching of the introduction of natural gas into the non-catalytic conversion furnace A / B and the glass furnace; for adjusting the flow of oxygen entering the glass furnace, for adjusting the flow of circulating flue gas entering the non-catalytic conversion furnace A / B, and for adjusting the flow of natural gas entering the non-catalytic conversion furnace A / B and the glass furnace, thereby controlling the furnace temperature and the furnace pressure of the glass furnace.

[0019] Furthermore, it is provided that during combustion, the isolation and replacement of a raw material supply system by circulating flue gas and the isolation of air leakage-prone areas of the glass furnace by circulating flue gas shall also take place, wherein the air leakage-prone areas of the glass furnace include a glass furnace supply opening, a flame observation opening and a smoke duct, and the isolation shall be effected, inter alia, by means of an air seal and an air curtain.

[0020] The present invention achieves the following advantageous effects: 1. In the present invention, a portion of the flue gas from the glass furnace is recirculated, thereby increasing the water vapor and carbon dioxide concentration of the circulating flue gas. The water vapor and carbon dioxide in the circulating flue gas undergo a conversion and reforming reaction with natural gas in a non-catalytic conversion furnace. While the sensible heat of high-temperature flue gas is recovered through the endothermic conversion and reforming reaction of natural gas, high-calorific-value water gas (carbon monoxide and hydrogen) above 1300°C is generated, thus increasing the overall calorific value of the gas entering the glass furnace and the furnace inlet temperature. High-calorific-value water gas, a small amount of natural gas that does not undergo the conversion and reforming reaction, and oxygen are completely combusted in the glass furnace, reducing fuel consumption and improving heat recovery efficiency.The invention has excellent performance in increasing production, saving energy and reducing emissions; it can reduce heat consumption and overall energy consumption, increase production, reduce flue gas emissions and achieve extremely low NOx emissions. 2. In the present invention, circulating flue gas and oxygen are used instead of air to promote combustion, thereby greatly reducing the formation of NOx, decreasing pollution and significantly lowering denitrification costs. 3. According to the properties of gas radiation, only triatomic and polyatomic gases have radiative properties, while diatomic gases exhibit almost no radiative properties. The higher the proportion of nitrogen, which lacks radiative properties, the lower the emissivity of the furnace gas, which affects the radiative power of the furnace gas on the molten glass. By replacing the combustion process with air-assisted combustion with circulating flue gas and oxygen, the N₂ content is significantly reduced.The flue gas circulation increases the concentration of water vapor and carbon dioxide in the furnace, while hydrogen and carbon monoxide are produced through non-catalytic conversion, which greatly increases the emissivity of the furnace gas and the radiation intensity for the mixture and the glass liquid, increases the flame temperature and reduces the emissivity of the smoke, accelerates the combustion rate, shortens the melting time, promotes complete combustion and increases the melting rate. 4. The present invention provides for a non-catalytic conversion furnace A and a non-catalytic conversion furnace B, and when the non-catalytic conversion furnace A is used to carry out a conversion and a reforming reaction, the non-catalytic conversion furnace B uses the high-temperature flue gas from the glass furnace outlet to be augmented and to store heat, thereby providing heat for the next conversion and reforming reaction; when the non-catalytic conversion furnace B is used for the conversion and reforming reaction, the non-catalytic conversion furnace A uses the high-temperature flue gas from the glass furnace outlet to be augmented and to store heat, thereby providing heat for the next conversion and reforming reaction;The non-catalytic conversion furnace A and the non-catalytic conversion furnace B are switched cyclically, which improves the heat utilization rate and speeds up work efficiency. 5. Once the system of the present invention enters normal operating condition, the process is divided into three phases: conversion and reforming phase, flue gas purging phase, and conversion furnace heating phase; In the conversion and reforming phase, water vapor and carbon dioxide from the circulating flue gas are used as raw materials, and the conversion and reforming reaction with natural gas is carried out in the non-catalytic conversion furnace to produce carbon monoxide and hydrogen, which increases the calorific value of the fuel and improves heat recovery efficiency;In the flue gas purging phase, the combustible gas remaining in the furnace during the conversion and reforming phase is reused to reduce fuel waste and avoid the pollution and safety risks caused by releasing the flue gas, which largely contains combustible gas, into the atmosphere during the conversion furnace heating phase. In the conversion furnace heating phase, the flue gas cycle is implemented, and the high-temperature flue gas at the glass furnace outlet is used to heat the non-catalytic conversion furnace and store heat, thus providing heat for the next conversion and reforming reaction. 6. In the conversion and reforming phase of the present invention, the introduction of natural gas into the non-catalytic conversion furnace is adjusted according to the varying oxygen content in the circulating flue gas. If the oxygen content in the circulating flue gas is less than or equal to the set limit, the natural gas enters the furnace from the bottom of the non-catalytic conversion furnace A, and the conversion and reforming reaction is completed. If the oxygen content in the circulating flue gas is greater than the set limit, natural gas enters the furnace from the top of the non-catalytic conversion furnace A, thereby shortening the conversion and reforming reaction time and minimizing the combustion reaction (only heat is supplied), which leads to waste and thus ensures a high level of safety. 7. The present invention further comprises insulating and replacing the raw material feed system using circulating flue gas during combustion, and using circulating flue gas by means of a gas seal, air curtain, etc., to insulate the areas of the glass furnace susceptible to air leakage, including the glass furnace feed opening, the flame observation opening, the flue duct, etc., thereby reducing radiant heat dissipation and the amount of ingressing air. In addition to preventing the generation of nitrogen oxides, the amount of flue gas circulation can also be reduced, effectively achieving energy savings and emission reduction. 8. Optimizing the combustion environment results in a more balanced temperature distribution within the furnace and effectively extends the service life of both the furnace and the boiler. Improving combustion conditions in the glass industry also reduces furnace heating time, increases production, lowers the defect rate, and improves yield. 9. The combustion process of the present invention can increase the emission rate, accelerate the combustion rate, and increase the flame temperature. Furthermore, the unburned material carried in the flue gas is also completely combusted, and the emission rate of the exhausted smoke is reduced. The flammable harmful gases that decompose and are formed by combustion are completely combusted, thus reducing the generation of harmful gases. The temperature and quantity of exhausted smoke are significantly reduced, thereby reducing thermal pollution and dust emissions. 10. The flue gas is circulated, thereby increasing the concentration of carbon dioxide, facilitating carbon dioxide capture and creating favorable conditions for cost-effective CCUS (carbon capture, carbon storage, carbon utilization). PRESENTATION OF THE INVENTION

[0021] This shows Fig. 1 a schematic diagram of the system used in the combustion of the present invention (in the non-catalytic conversion furnace A a conversion and reforming reaction takes place, and the non-catalytic conversion furnace B heats up and heat is stored therein), Fig. 2 a schematic diagram of the system used in the combustion of the present invention (in the non-catalytic conversion furnace B a conversion and reforming reaction takes place, and the non-catalytic conversion furnace A heats up and heat is stored therein), Fig. 3 a schematic diagram of the switching of the non-catalytic conversion furnace A and the non-catalytic conversion furnace B of the present invention, Fig. 4 a schematic diagram of the combustion logic control of the present invention. SPECIFIC EXECUTION FORMS

[0022] The invention is further explained below in conjunction with exemplary embodiments and drawings. The following exemplary embodiments are used only to illustrate the invention and are not intended to limit the scope of its implementation.

[0023] Principle of conventional air-assisted combustion: C m H n O2 + N2 → CO2 + H2O + NO X ;

[0024] Principle of promoting combustion by carbon-based oxygen enrichment (H2O+CO2+O2) of the invention as well as the conversion and reforming reaction of natural gas and circulating flue gas containing high levels of water vapor and carbon dioxide: Combustion reaction H2 + 1 / 2O2 → H2O + 242 kJ / mol CH4+2O2 → CO2+2H2O+802 KJ / mol CO+O2 → 1 / 2CO2+393 kJ / mol Conversion reaction CH4+1 / 2O2 → CO+2H2+35.5 KJ / mol CH4+H2O → CO+3H2 - 206 kJ / mol CH4+CO2 → 2CO+2H2-247 KJ / mol

[0025] A combustion process for a glass furnace with a non-catalytic conversion furnace is provided. As in Fig. 1 and Fig. As shown in Figure 2, the system required for combustion comprises a glass furnace 3, a non-catalytic conversion furnace A4, a non-catalytic conversion furnace B5, a flue gas recovery device 7, a chimney 8, a high-temperature flue gas fan 6, a natural gas supply device 2 and an oxygen supply device 1;

[0026] In the case of the non-catalytic conversion furnace A4 and the non-catalytic conversion furnace B5, one non-catalytic conversion furnace A4 and one non-catalytic conversion furnace B5 are assigned as a pair, and depending on the size of the glass furnace, several pairs can be flexibly provided. Fig. 1 and Fig. Figure 2 shows 3 pairs designed for the conversion and reforming reaction of water vapor and carbon dioxide into natural gas with circulating flue gas, and which also function as a heat storage system to recover heat from circulating high-temperature flue gas;

[0027] The flue gas recovery device 7 serves to recover heat, remove dust and desulfurize circulating high-temperature flue gas from the non-catalytic conversion furnace A4 / B5;

[0028] The high-temperature flue gas fan 6 is a variable-frequency high-temperature flue gas fan that pressurizes the circulating flue gas after heat recovery, dust removal, and desulfurization and introduces it into the non-catalytic conversion furnace A4 / B5; The high-temperature flue gas fan 6 can also be a conventional high-temperature flue gas fan, but a flow control valve must be additionally provided at the outlet;

[0029] The natural gas supply device 2 serves to provide natural gas;

[0030] The oxygen supply device 1 provides oxygen and selects an oxygen production method according to the size of the glass furnace 3, such as cryogenic freezing, pressure swing adsorption, etc. The oxygen purity is ≥ 90% and the pressure is 0.05 to 0.2 MPa. For large glass furnaces, cryogenic freezing is used to produce oxygen. In this process, air is first compressed, cooled, and thus liquefied. Utilizing the difference in the boiling points of the oxygen and nitrogen components, the gas and liquid are brought into contact on the distillation plate, resulting in heat and mass transfer. The oxygen component, with its high boiling point, continuously condenses from the vapor into a liquid.The nitrogen component, with its low boiling point, is continuously transferred into the vapor, so that the nitrogen content in the rising vapor is continuously increased, while the oxygen content in the downward-flowing liquid becomes increasingly higher, so that oxygen and nitrogen are separated to obtain oxygen with a purity of 99.6% or more, and the oxygen flow is controlled by the flow control valve and introduced into the glass furnace 3 through an oxygen spray gun; for small and medium-sized glass furnaces, the pressure swing adsorption process is used to generate oxygen.When air is subjected to higher pressure through an adsorption layer of the molecular sieve adsorption tower, the nitrogen molecules are preferentially adsorbed, and the oxygen molecules remain in the gas phase to obtain oxygen as the finished product. When the nitrogen component in the adsorbent reaches saturation, the nitrogen molecules adsorbed on the surface of the adsorbent are desorbed by decompression or vacuum suction and removed from the boundary zone to restore the adsorbent's adsorption capacity. This separates oxygen and nitrogen to obtain oxygen with a purity of 90-95%, and the oxygen flow is controlled by a flow control valve and introduced into the glass furnace 3 via the oxygen spray gun.

[0031] The non-catalytic conversion furnace A4 and the non-catalytic conversion furnace B5 are arranged on two sides of the glass furnace 3 and connected to the glass furnace 3; wherein the non-catalytic conversion furnace A4 and the non-catalytic conversion furnace B5 are switchably connected to an inlet of the flue gas recovery device 7 and an outlet of the flue gas recovery device 7 is each connected to the chimney 8 and the high-temperature flue gas fan 6, wherein the high-temperature flue gas fan 6 is connected to the bottom of the non-catalytic conversion furnace A4 and the bottom of the non-catalytic conversion furnace B5;

[0032] The natural gas supply device 2 is switchably connected to the bottom of the non-catalytic conversion furnace A4, the upper part of the non-catalytic conversion furnace A4, the bottom of the non-catalytic conversion furnace B5, the upper part of the non-catalytic conversion furnace B5 and the glass furnace 3.

[0033] The oxygen supply device 1 is connected to the glass furnace 3;

[0034] An oxygen content analyzer, a flow meter, a temperature sensor and a pressure sensor are provided on a pipe through which the high-temperature flue gas fan 6 is connected to the bottom of the non-catalytic conversion furnace A4 and the bottom of the non-catalytic conversion furnace B5, wherein a flow control valve and a pressure sensor are provided on a pipe through which the natural gas supply device 2 is connected to the bottom of the non-catalytic conversion furnace A4, the upper part of the non-catalytic conversion furnace A4, the bottom of the non-catalytic conversion furnace B5, the upper part of the non-catalytic conversion furnace B5 and the glass furnace 3, and wherein a flow control valve and the pressure sensor are provided on a pipe through which the oxygen supply device 1 is connected to the glass furnace 3.

[0035] Preferably, the system is further provided to include an intelligent control system for controlling the switching of the non-catalytic conversion furnace A4 / B5, for controlling the switching of the introduction of natural gas into the non-catalytic conversion furnace A4 / B5 and the glass furnace 3 (switching schematically shown in Fig. 3 shown); for adjusting the flow of oxygen entering the glass furnace 3, for adjusting the flow of circulating flue gas entering the non-catalytic conversion furnace A4 / B5, and for adjusting the flow of natural gas entering the non-catalytic conversion furnace A4 / B5 and the glass furnace 3, thereby controlling the furnace temperature and furnace pressure of the glass furnace 3.

[0036] As in Fig. As shown in Figure 4, combustion comprises the following steps: 1) In the initial phase, air is used to promote combustion and enters the glass furnace 3 through the non-catalytic conversion furnace A4, while natural gas enters the glass furnace 3 directly, where air and natural gas are combusted. The flue gas produced by the combustion flows through the non-catalytic conversion furnace B5 to heat it and store heat, then enters the flue gas recovery device 7 to recover heat and be dedusted and desulfurized. Afterward, it is introduced into the non-catalytic conversion furnace A4 via the high-temperature flue gas fan 6 and then enters the glass furnace 3, with oxygen simultaneously being introduced into the glass furnace 3 via an oxygen spray gun.to replace the need for air-assisted combustion by means of a mixture of circulating flue gas and oxygen (carbon-based oxygen enrichment); wherein after a while the non-catalytic conversion furnace A4 / B5 is switched over and air enters the glass furnace 3 through the non-catalytic conversion furnace B5, while natural gas enters the glass furnace 3 directly, wherein air and natural gas are combusted in a glass furnace 3 and the flue gas produced by the combustion flows through the non-catalytic conversion furnace A4 to heat the non-catalytic conversion furnace A4 and store heat there, then enters the flue gas recovery device 7 to recover heat and be dedusted and desulfurized, is then introduced via the high-temperature flue gas fan 6 into the non-catalytic conversion furnace B5 and then enters the glass furnace 3,wherein oxygen is simultaneously introduced into the glass furnace 3 via an oxygen spray gun in order to promote combustion by means of a mixture of the circulating flue gas and the oxygen and to gradually replace the promotion of combustion with air, whereby such a switching is repeated cyclically; wherein after a certain time of the cycle the circulating flue gas contains a high content of water vapor and carbon dioxide and the circulating flue gas and the oxygen completely replace the promotion of combustion with air, whereby the system enters the normal operating state. 2) Conversion and Reforming Phase: The conversion and reforming phase takes place from minute 0 to 17. When the oxygen content in the circulating flue gas is less than or equal to a set limit of 2%, the circulating flue gas enters the furnace from the bottom of the non-catalytic conversion furnace A4, and natural gas also enters the furnace from the bottom of the non-catalytic conversion furnace A4. The natural gas undergoes a conversion and reforming reaction with water vapor and carbon dioxide in the circulating flue gas, producing hydrogen and carbon monoxide (high-calorific-value water gas). (The conversion and reforming reactions can occur above 750 °C and do not require a catalyst.) This hydrogen and carbon monoxide are fed into the glass furnace 3. Oxygen is introduced into the glass furnace 3 via an oxygen spray gun and reacts with the carbon monoxide and hydrogen produced by the non-catalytic conversion.and a small quantity of natural gas, which does not undergo a conversion and reforming reaction, undergoes a combustion reaction in the glass furnace 3; wherein the circulating flue gas, when the oxygen content in the circulating flue gas is greater than the set content limit of 2%, enters the furnace from the bottom of the non-catalytic conversion furnace A4, and natural gas enters the furnace from the upper region of the non-catalytic conversion furnace A4, namely from a position at a distance of 1 / 5 to 1 / 3 from the top of the non-catalytic conversion furnace A4, wherein natural gas undergoes a conversion and a reforming reaction with water vapor and carbon dioxide in the circulating flue gas, thereby producing hydrogen and carbon monoxide, namely high-calorific-value water gas, and feeding it into the glass furnace 3, wherein oxygen is fed into the glass furnace 3 by an oxygen spray gun and is combined with carbon monoxide and hydrogen,which are produced by non-catalytic conversion, and a small amount of natural gas that does not undergo a conversion and reforming reaction, in which a combustion reaction takes place in glass furnace 3; 3) Flue gas purging phase: The flue gas purging phase takes place from minute 18 to 20. After completion of the conversion and reforming phase, the natural gas is fed directly into glass furnace 3, and the circulating flue gas enters the furnace from the bottom of the non-catalytic conversion furnace A4 to purge, replace, and convert the remaining combustible gas. Oxygen is then injected into glass furnace 3 via an oxygen spray gun to initiate a combustion reaction. 4) Heating phase of the conversion furnace: From minute 0 to 20, the heating phase of the conversion furnace takes place. During the conversion and reforming phase and the flue gas purging phase, high-temperature flue gas from the outlet of the glass furnace 3 enters the non-catalytic conversion furnace B5 to heat the furnace and store heat, and then enters the flue gas recovery device 7 to recover heat and be dedusted and desulfurized, after which approximately 20% to 30% of the flue gas is subjected to a pressure of 0.05 to 0.2 MPa by the high-temperature flue gas fan 6 and then introduced into the circulation of the non-catalytic conversion furnace A4, while the remainder is discharged through the chimney 8 or undergoes a CCUS process; 5) The non-catalytic conversion furnace A / B is switched every 20 minutes. The non-catalytic conversion furnace A4 / B5 is switched, meaning that a conversion and a reforming reaction take place in non-catalytic conversion furnace B5, while non-catalytic conversion furnace A4 heats up and stores heat; this switching process is repeated cyclically. The flue gas recirculation volume accounts for approximately 20 to 30% of the total flue gas volume.

[0037] When raw materials such as quartz sand, soda, dolomite, limestone, and Glauber's salt are fed into the glass furnace 3, air is entrained and adsorbed. Preferably, the raw material feed system is isolated and replaced by circulating flue gas to prevent the generation of nitrogen oxides originating from the raw materials. The circulating flue gas is used to isolate the points of the glass furnace 3 susceptible to air leakage. These points include a glass furnace feed opening, a flame observation opening, and a flue. The isolation is achieved, among other things, by means of an air seal and an air curtain to prevent the generation of thermal nitrogen oxides.

Claims

[1] Combustion method for a glass furnace with a non-catalytic conversion furnace, wherein the system required for combustion comprises a glass furnace, a non-catalytic conversion furnace A, a non-catalytic conversion furnace B, a flue gas recovery device, a chimney, a high-temperature flue gas fan, a natural gas supply device and an oxygen supply device; wherein the non-catalytic conversion furnace A and the non-catalytic conversion furnace B are arranged on two sides of the glass furnace and connected to the glass furnace; wherein the non-catalytic conversion furnace A and the non-catalytic conversion furnace B are switchably connected to an inlet of the flue gas recovery device and an outlet of the flue gas recovery device is each connected to the chimney and the high-temperature flue gas fan, the high-temperature flue gas fan being connected to the bottom of the non-catalytic conversion furnace A and the bottom of the non-catalytic conversion furnace B; wherein the natural gas supply device is switchably connected to the bottom of the non-catalytic conversion furnace A, the upper part of the non-catalytic conversion furnace A, the bottom of the non-catalytic conversion furnace B, the upper part of the non-catalytic conversion furnace B and the glass furnace, the oxygen supply device is connected to the glass furnace; wherein an oxygen content analyzer, a flow meter, a temperature sensor and a pressure sensor are provided on a pipe through which the high-temperature flue gas fan is connected to the bottom of the non-catalytic conversion furnace A and the bottom of the non-catalytic conversion furnace B, wherein a flow control valve and a pressure sensor are provided on a pipe through which the natural gas supply device is connected to the bottom of the non-catalytic conversion furnace A, the upper part of the non-catalytic conversion furnace A, the bottom of the non-catalytic conversion furnace B, the upper part of the non-catalytic conversion furnace B and the glass furnace, and wherein a flow control valve and the pressure sensor are provided on a pipe through which the oxygen supply device is connected to the glass furnace; the combustion process includes the following steps: 1) In the initial phase, combustion is promoted by means of air, and after the generation of the flue gas, the circulating flue gas is mixed with oxygen and used as a combustion improver to gradually replace the promotion of combustion with air, whereby after a certain time of the cycle the circulating flue gas contains high levels of water vapor and carbon dioxide, and the circulating flue gas and the oxygen completely replace the promotion of combustion with air, at which point the system enters its normal operating state; 2) Conversion and Reforming Phase: When the oxygen content in the circulating flue gas is less than or equal to a set limit, the circulating flue gas enters the furnace from the bottom of the non-catalytic conversion furnace A, and natural gas also enters the furnace from the bottom of the non-catalytic conversion furnace A, whereby the natural gas undergoes a conversion and reforming reaction with water vapor and carbon dioxide in the circulating flue gas, producing hydrogen and carbon monoxide, namely high-calorific-value water gas, which are fed into the glass furnace, whereby oxygen is fed into the glass furnace and undergoes a combustion reaction with carbon monoxide and hydrogen produced by non-catalytic conversion and a small amount of natural gas that does not undergo a conversion and reforming reaction;wherein the circulating flue gas, when the oxygen content in the circulating flue gas is greater than the set content limit, enters the furnace from the bottom of the non-catalytic conversion furnace A and natural gas enters the furnace from the upper part of the non-catalytic conversion furnace A, wherein natural gas undergoes a conversion and a reforming reaction with water vapor and carbon dioxide in the circulating flue gas, thereby producing hydrogen and carbon monoxide, namely water gas with a high calorific value, and feeding it into the glass furnace, wherein oxygen is fed into the glass furnace and undergoes a combustion reaction in the glass furnace with carbon monoxide and hydrogen produced by non-catalytic conversion and a small amount of natural gas that does not undergo a conversion and reforming reaction; 3) Flue gas purging phase: After completion of the conversion and reforming phase, the natural gas is fed directly into the glass furnace and the circulating flue gas enters the furnace from the bottom of the non-catalytic conversion furnace A to purge, replace and convert the remaining combustible gas, and enters the glass furnace, with oxygen being fed into the glass furnace to undergo a combustion reaction; 4) Heating phase of the conversion furnace: In the conversion and reforming phase and the flue gas purging phase, high-temperature flue gas from the outlet of the glass furnace enters the non-catalytic conversion furnace B to heat the furnace and store heat, and then enters the flue gas recovery device to recover heat and be dedusted and desulfurized, after which part is pressurized by the high-temperature flue gas fan and then introduced into the circulation of the non-catalytic conversion furnace A, while the remainder is discharged through the chimney or undergoes a CCUS process; 5) After a certain time, the non-catalytic conversion furnace A / B is switched over, that is, a conversion and a reforming reaction take place in the non-catalytic conversion furnace B, and the non-catalytic conversion furnace A heats up and heat is stored there; such a switching is repeated cyclically. [2] Combustion drive according to claim 1, characterized by that the oxygen supply device produces oxygen by means of a deep-freeze process or a pressure swing adsorption process with an oxygen purity of ≥ 90% and a pressure of 0.05 to 0.2 MPa. [3] Combustion drive according to claim 1, characterized byStep 1) In the initial phase, air is used to promote combustion and enters the glass furnace through the non-catalytic conversion furnace A, while natural gas enters the glass furnace directly, where air and natural gas are burned. The flue gas produced by the combustion flows through the non-catalytic conversion furnace B to heat and store heat, then enters the flue gas recovery device to recover heat and be dedusted and desulfurized. Afterward, it is introduced via the high-temperature flue gas fan into the non-catalytic conversion furnace A and then enters the glass furnace, with oxygen also being introduced into the glass furnace at the same time.to replace the need for air-assisted combustion with a mixture of circulating flue gas and oxygen; wherein, after a while, the non-catalytic conversion furnace A / B is switched over and air enters the glass furnace through the non-catalytic conversion furnace B, while natural gas enters the glass furnace directly, wherein air and natural gas are combusted in a glass furnace and the flue gas produced by the combustion flows through the non-catalytic conversion furnace A to heat the non-catalytic conversion furnace A and store heat there, then enters the flue gas recovery device to recover heat and be dedusted and desulfurized, is then introduced via the high-temperature flue gas fan into the non-catalytic conversion furnace B and then enters the glass furnace, with oxygen being introduced into the glass furnace at the same time.to promote combustion by means of a mixture of circulating flue gas and oxygen and to gradually replace the promotion of combustion with air, whereby such a switching is repeated cyclically; wherein after a certain time of the cycle the circulating flue gas contains a high content of water vapor and carbon dioxide and the circulating flue gas and oxygen completely replace the promotion of combustion with air, whereby the system enters its normal operating state. [4] Combustion drive according to claim 1, characterized by , that in steps 2) to 5) the non-catalytic conversion furnace A / B is switched every 20 minutes, with the conversion and reforming phase taking place from 0 to 17 minutes, the flue gas purging phase taking place from 18 to 20 minutes and the heating phase of the conversion furnace taking place from 0 to 20 minutes. [5] Combustion drive according to claim 1, characterized by, that the oxygen content limit in the circulating flue gas is set to 2% in step 2). [6] Combustion drive according to claim 1, characterized by , that in step 2) natural gas from the upper area of ​​the non-catalytic conversion furnace A enters the furnace, namely from a position at a distance of 1 / 5 to 1 / 3 from the top of the non-catalytic conversion furnace A, if the oxygen content in the circulating flue gas is greater than the set content limit. [7] Combustion drive according to claim 1, characterized by , that in steps 2), 3) and 5) oxygen is fed into the glass furnace through an oxygen spray gun. [8] Combustion drive according to claim 1, characterized by, that the circulating flue gas, after heat recovery, dust removal and desulfurization in step 4), is subjected to a pressure of 0.05 to 0.2 MPa by the high-temperature flue gas fan and is then introduced into the non-catalytic conversion furnace A for recirculation. [9] Combustion drive according to claim 1, characterized by, that the system required for combustion further comprises an intelligent control system for controlling the switching of the non-catalytic conversion furnace A / B, for controlling the switching of the introduction of natural gas into the non-catalytic conversion furnace A / B and the glass furnace; for adjusting the flow of oxygen entering the glass furnace, for adjusting the flow of circulating flue gas entering the non-catalytic conversion furnace A / B, and for adjusting the flow of natural gas entering the non-catalytic conversion furnace A / B and the glass furnace, thereby controlling the furnace temperature and the furnace pressure of the glass furnace. [10] Combustion drive according to claim 1, characterized by, that during combustion, the isolation and replacement of a raw material supply system by circulating flue gas and the isolation of air leakage-prone areas of the glass furnace by circulating flue gas shall also take place, wherein the air leakage-prone areas of the glass furnace shall include a glass furnace supply opening, a flame observation opening and a smoke duct, and the isolation shall be effected, inter alia, by means of an air seal and an air curtain.

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