Cement production line recycling system and method

Abstract

The invention relates to the technical field of cement production, and provides a cement production line recycling system which comprises a circulation gas conveying pipeline, a combustion conveying pipeline, an oxygen conveying pipeline and a methanol mixing pipeline which are connected through pipelines, and the combustion conveying pipeline and the methanol mixing pipeline both communicate with the circulation gas conveying pipeline; the circulating gas conveying pipeline is sequentially connected with a clinker sintering system, a first heat exchanger, a first SCR (Selective Catalytic Reduction) device, a booster fan, a dust collector, a circulating fan and a water removal device; the clinker sintering system is provided with a feeding end, a combustion end and an exhaust end, and carbon dioxide generated by sintering cement clinker is mixed into circulating gas; the circulating gas is conveyed to the water removal device from the exhaust end in sequence, and meanwhile, after the water removal device removes water from the circulating gas, the circulating gas is conveyed back to the clinker sintering system to form cyclic utilization of the circulating gas. The method has the effect of recycling resources. In addition, the invention further provides a cement production line recycling method.

Description

Technical Field

[0001] The present application relates to the technical field of cement production, and in particular to a cement production line resource utilization system and method. Background Art

[0002] Due to the scale of cement production and the characteristics of its production process (process emissions), the cement industry is considered to be one of the main sources of anthropogenic carbon dioxide emissions, accounting for approximately 8% of global carbon emissions. Therefore, carbon dioxide emissions during cement production need to be controlled.

[0003] When producing cement, the use of oxygen-enriched combustion is considered to recycle carbon dioxide. Oxygen-enriched combustion capture refers to the use of a high-concentration mixed gas of oxygen and carbon dioxide instead of air to react with coal powder and other fuels in the kiln. The carbon dioxide generated during cement sintering is recycled, thereby reducing carbon dioxide emissions.

[0004] The existing oxygen-enriched combustion carbon capture system suffers from severe air leakage, resulting in low carbon dioxide concentration in the circulating gas. The subsequent process route has to purify the carbon dioxide before use, resulting in the failure to achieve comprehensive utilization of technical energy and materials, low system integration, and high investment and operating costs. Summary of the invention

[0005] In order to improve the above-mentioned problems, the present application provides a cement production line resource utilization system and method.

[0006] The present application provides a cement production line resource utilization system and method using the following technical solutions: A cement production line resource recovery system, comprising the following pipeline-connected systems or devices: a circulating gas delivery pipeline, a combustion delivery pipeline, an oxygen delivery pipeline and a methanol mixing pipeline, wherein the combustion delivery pipeline and the methanol mixing pipeline are both connected to the circulating gas delivery pipeline; The circulating gas transmission pipeline is sequentially connected to the clinker burning system, the first heat exchanger, the first SCR device, the booster fan, the dust collector, the circulating fan and the dehydration device; the clinker burning system is provided with a feed end, a combustion end and an exhaust end, and the combustion end is a kiln tail burner and a kiln head burner; the carbon dioxide generated by the sintering of cement clinker is mixed into the circulating gas; the circulating gas is transported from the exhaust end to the dehydration device in sequence, and the dehydration device removes water from the circulating gas and then transports it back to the clinker burning system to form a circulating gas. The combustion and transportation pipeline is connected to the pipeline between the dewatering device and the clinker burning system, including a conveying fan, an air compressor device, a ash cleaning system, a second heat exchanger, a sealing system and a pulverized coal transportation system; the second heat exchanger, the conveying fan, the sealing system and the pulverized coal transportation system are connected to the pipeline behind the dewatering device; the air compressor device is connected to the second heat exchanger, and the ash cleaning system is connected to the air compressor device; the conveying fan and the other end of the pulverized coal transportation system are connected to the combustion end; The methanol mixing pipeline is initially connected to the pipeline between the circulating fan and the water removal device, and is sequentially connected to the raw gas purification system, the methanol synthesis device, the power-to-gas device, the methanol fuel cell and the methanol storage tank; a part of the circulating gas enters the raw gas purification system, is purified to form clean raw gas, and is transported to the methanol synthesis device, and the purge gas generated by the methanol synthesis device enters the combustion end; the power-to-gas device adds water to decompose to form hydrogen and oxygen, the oxygen is connected to the oxygen transmission pipeline, the hydrogen enters the methanol synthesis device to synthesize methanol, and is stored in the methanol storage tank; the methanol storage tank is connected to the first SCR device, the methanol fuel cell and the combustion end, and transports methanol; The oxygen transmission pipeline includes an air separation oxygen production device and an oxygen storage tank; the air separation oxygen production device extracts air to separate oxygen, and separates it into five pipelines for transportation; the first pipeline is connected to the oxygen storage tank; the second pipeline is connected to the kiln tail burner; the third pipeline is connected to the kiln head burner; the fourth pipeline is connected to the discharge end; and the fifth pipeline is connected to the methanol fuel cell.

[0007] By adopting the above technical scheme, when the raw material is sintered into a shape, the gas generated by the oxygen-enriched combustion continues to circulate in the circulating gas conveying pipeline, and after the nitrogen oxides are removed, the carbon dioxide is recycled to reduce the emission of carbon dioxide. The hydrogen formed by the decomposition of oxygen can participate in the synthesis of methanol. After the methanol reduces the nitrogen oxides, it can also provide auxiliary combustion. The sealing system is used to close the air leakage generated during the combustion process to prevent air from entering and diluting the carbon dioxide concentration in the circulating gas, thereby achieving the comprehensive utilization of technical energy and materials and reducing the operating cost.

[0008] Optionally, the clinker burning system includes: a grate cooler, a rotary kiln, a kiln head hood, a smoke chamber, a decomposition furnace, a preheater group, a pressure reamer and an air cannon; wherein the grate cooler is divided into a first cooling zone, a second cooling zone and a third cooling zone; the pressure reamer connects the connecting pipe between the second preheater and the first preheater; the preheater group includes a first preheater, a second preheater, a third preheater, a fourth preheater and a fifth preheater which are connected in sequence; the fifth preheater is connected to the decomposition furnace; a kiln tail burner is arranged on the decomposition furnace, the decomposition furnace is connected to the smoke chamber, the smoke chamber is connected to one end of the rotary kiln, and the other end of the rotary kiln is connected to the kiln head hood and the first cooling zone of the grate cooler; the kiln tail burner is connected to the pipelines of methanol, oxygen and circulating gas.

[0009] By adopting the above technical scheme, the raw material is preheated by using the first preheater to the fifth preheater, decomposed in the decomposition furnace, and finally sintered into clinker by the rotary kiln, and then cooled by the first cooling zone, the second cooling zone and the third cooling zone of the grate cooler to achieve the purpose of cooling and recovering the clinker.

[0010] Optionally, the sealing system includes: a kiln head sealing device and a kiln tail sealing device; the kiln head sealing device is installed at the kiln head of the rotary kiln, and the kiln tail sealing device is installed at the kiln tail of the rotary kiln.

[0011] By adopting the above technical solution, the kiln head sealing device and the kiln tail sealing device respectively seal the kiln head of the rotary kiln to prevent the outside air from entering during the oxygen-enriched combustion of raw materials.

[0012] Optionally, the kiln head sealing device adopts a double-layer fish scale sealing structure; a plurality of sealing sheets are stacked respectively to form two layers of fish scale-shaped annular cover bodies, one end of which is fixed on the sealing cover, and the other end is pressed on the friction ring, and the friction ring is fixed on the outer wall of the rotary kiln; the sealing cover is fixed on the kiln head cover, and the sealing cover is provided with a kiln head circulating gas inlet 1, a kiln head circulating gas inlet 2, and a circulating gas outlet; the two layers of sealing sheets, the friction ring and the sealing cover together form an isolation chamber.

[0013] By adopting the above technical solution, the pipeline after the water removal device is connected to the sealing system, so that the circulating gas can provide positive micro-pressure to the kiln head sealing device in the sealing system, and part of the circulating gas passes through the gap between the sealing plates into the external air, which prevents the external air from entering the isolation cavity, thereby ensuring the sealing effect.

[0014] Optionally, the kiln tail sealing device adopts a double-layer sealing structure of compression seal and fish scale seal; the isolation cover is fixed on the side wall of the smoke chamber, and one end of the fish scale-shaped annular cover body formed by a plurality of fish scales is fixed on the isolation cover, and the other end is pressed on the contact ring, and the contact ring is fixed on the rotating end of the compression seal; the isolation cover, fish scales, and contact ring constitute a fish scale sealing structure; the contact part of the compression seal fixed end and the compression seal rotating end forms a friction pair to constitute a compression seal structure; the isolation cover, fish scales, contact ring, compression seal fixed end, and compression seal rotating end together form a sealing cavity.

[0015] By adopting the above technical solution, the pipeline after the water removal device is connected to the sealing system, so that the circulating gas can provide positive micro-pressure to the kiln tail sealing device in the sealing system, and the rotating end of the compression seal rotates with the rotary kiln to form a double sealing structure of fish scales and friction pairs, so that the kiln tail sealing device isolates the outside air from entering the system.

[0016] Optionally, the raw gas purification system includes an absorption tower, a second SCR device, a pressure swing adsorption device, a fan, a chimney, a hot air device, a regeneration tower, and a sulfur recovery device; activated carbon is provided in the absorption tower, and the absorption tower is respectively connected to the second SCR device and the regeneration tower; the regeneration tower is respectively connected to the hot air device and the sulfur recovery device; the second SCR device is respectively connected to the pressure swing adsorption device and the chimney, and the pressure swing adsorption device is connected to the methanol synthesis device; wherein, when the air separation oxygen production device separates oxygen, one path is separated to the hot air device.

[0017] By adopting the above technical scheme, part of the circulating gas separated from the circulating fan can be purified through the raw gas purification system, and the reduced clean raw gas can participate in the synthesis of methanol, and the generated methanol can participate in the reduction and removal of nitrogen oxides in the circulating gas, thereby rationalizing resource allocation and utilization.

[0018] Optionally, it also includes wind power and photovoltaic power generation systems, which are respectively connected to the power-to-gas device, the air separation oxygen production device and the methanol synthesis device, and provide power supply; the wind power and photovoltaic power generation systems supply electricity to the methanol fuel cell for power storage.

[0019] By adopting the above technical scheme, the wind power and photovoltaic power generation systems can provide their own power supply, so that the air separation oxygen production device, the methanol synthesis device, and the power-to-gas device can all obtain power supply, reducing the transmission of external power and rationally utilizing circulating resources. At the same time, the methanol fuel cell can utilize the methanol synthesized by the methanol synthesis device and the oxygen separated by the air separation oxygen production device to generate electricity, thereby making up for the insufficient power supply in the wind power and photovoltaic power generation systems. The carbon dioxide generated is then transported to the methanol synthesis device as a raw material for synthesizing methanol, thereby further improving the utilization rate of resources.

[0020] Optionally, a dust cleaning device is provided in the first heat exchanger.

[0021] By adopting the above technical solution, when the first heat exchanger cools down the circulating gas for heat exchange, due to the presence of dust in the raw material, the dust will stick to the first heat exchanger. When the dust accumulates too much, it will easily lead to a decrease in the heat exchange effect. Therefore, a cleaning device is provided to clean the attached dust to ensure the stability of the heat exchange.

[0022] A cement production line resource utilization method comprises the following steps: During the sintering process of cement clinker in the clinker burning system, carbon dioxide and nitrogen oxides are generated. The circulating gas rich in high concentration of carbon dioxide enters the circulating gas transmission pipeline, passes through the first heat exchanger, is mixed and homogenized with methanol from the methanol storage tank, and then enters the first SCR device. A methanol catalyst is provided in the first SCR device. The circulating gas and methanol mixed gas are catalytically reduced to most of the nitrogen oxides under the action of the methanol catalyst, and then pass through the booster fan and the dust collector for dust removal before entering the circulating fan. After passing through the circulating fan, the circulating gas is divided into two routes: the first circulating gas enters the raw gas purification system of the methanol mixing pipeline, and enters the methanol synthesis unit after purification; the second circulating gas continues to go through the circulating gas transmission pipeline to the dehydration device, and the dehydration device removes part of the water and then continues to be recycled; In the raw gas purification system of the methanol mixing pipeline, the circulating gas first passes through the absorption tower. After the activated carbon in the absorption tower adsorbs the sulfide in the circulating gas, the circulating gas is mixed with the methanol from the methanol storage tank and homogenized before entering the second SCR device. The second SCR device is provided with a methanol catalyst. The circulating gas and methanol mixed gas are catalytically reduced to all nitrogen oxides under the action of the methanol catalyst and then enter the methanol synthesis device to synthesize methanol and generate purge gas. The purge gas enters the combustion end, and the methanol enters the methanol storage tank. After the circulating gas has part of its water removed by the dehydration device, it enters the combustion and transportation pipeline and the clinker burning system, and is divided into four routes in the combustion and transportation pipeline: the first route lowers the temperature through the second heat exchanger and then goes to the air compressor device and then to the ash cleaning system; the second route goes to the conveying fan; the third route goes to the coal powder conveying system, and the fourth route goes to the sealing system; the transportation to the clinker burning system is divided into two routes, the first route is mixed with the high-concentration oxygen from the air separation oxygen production device and then goes to the first cooling zone of the grate cooler; the second route goes to the second cooling zone of the grate cooler, thereby realizing the circulation of carbon dioxide.

[0023] By adopting the above technical scheme and utilizing the resource recovery method, nitrogen oxides can be removed from the circulating gas during recycling, and the methanol used during the removal is used for purification, generation and synthesis in the circulating gas, thereby rationally allocating and utilizing resources and reducing waste of resources.

[0024] Optionally, the clinker burning system includes the following steps: when the pressure reamer is working, the interior is filled with raw meal, and the raw meal is pushed into the system by the spiral blades, and the raw meal enters the connecting pipeline from the second-stage preheater to the first-stage preheater, and performs heat exchange with the circulating gas rich in high-concentration carbon dioxide in the pipeline, and enters the first-stage preheater with the circulating gas; The raw meal in the circulating gas is collected by the first stage preheater and enters the connecting pipe between the third stage preheater and the second stage preheater, and enters the second stage preheater after heat exchange with the circulating gas; The raw meal is heat exchanged with the circulating gas in the second to fourth stage preheaters in sequence and then enters the decomposition furnace; After being pre-decomposed in the decomposition furnace, the raw material enters the fifth-stage preheater, is collected by the fifth-stage preheater, and then enters the smoke chamber, and then enters the rotary kiln. After being burned into mature material in the rotary kiln, it enters the first cooling zone of the grate cooler; The clinker is cooled to the required temperature in the first cooling zone, the second cooling zone and the third cooling zone of the grate cooler in turn and then stored in the clinker warehouse; The carbon dioxide and nitrogen oxides generated during the sintering process of the rotary kiln to produce clinker and the carbon dioxide and nitrogen oxides generated during the decomposition in the decomposition furnace follow the circulating gas, enter the first heat exchanger, and circulate in the circulating transport pipeline.

[0025] By adopting the above technical solution, the raw material is sintered into cement clinker through the clinker burning system, and the generated carbon dioxide and nitrogen oxides enter the circulating transmission pipeline for circulation, thereby ensuring the circulation stability of the circulating gas.

[0026] In summary, the present application includes at least one of the following beneficial technical effects: 1. When the raw material is sintered, the gas generated by oxygen-enriched combustion continues to circulate in the circulating gas pipeline. After the nitrogen oxides are removed, the carbon dioxide is recycled to reduce the emission of carbon dioxide. The hydrogen formed by the decomposition of oxygen can participate in the synthesis of methanol. After the methanol reduces the nitrogen oxides, it can also provide auxiliary combustion. The air leakage generated during the combustion process is closed by the sealing system to prevent air from entering and diluting the carbon dioxide concentration in the circulating gas, thereby achieving the comprehensive utilization of technical energy and materials and reducing the operating cost. 2. The fuel in the methanol fuel cell comes from the methanol storage tank, and the oxygen as the oxidant comes from the air separation oxygen production device. The present invention ensures the purity and oxygen supply rate of oxygen. Maintaining sufficient oxygen supply and high purity helps to improve the efficiency of the fuel cell; 3. This scheme uses methanol for denitrification. In order to ensure the denitrification efficiency, an appropriate excess amount can be added to the denitrification device. On the one hand, methanol is self-produced, and the operating cost of denitrification is low; on the other hand, the excess methanol after denitrification circulates within the system and can be burned as fuel in the combustion system without causing leakage and other problems.

[0027] The purge gas is introduced into the decomposition furnace for combustion to avoid exhaustion and air pollution. Some combustibles in the purge gas can be used as fuel. In addition, the water vapor in the purge gas can reduce the temperature of calcium carbonate decomposition in the decomposition furnace under high partial pressure of carbon dioxide, which can save fuel and reduce temperature to prevent equipment from crusting. 4. The pipeline after the water removal device is connected to the sealing system, so that the circulating gas can provide positive micro-pressure to the kiln head sealing device in the sealing system. Part of the circulating gas passes through the gap between the sealing plates and enters the external air, which prevents the external air from entering the isolation chamber and ensures the sealing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a process flow chart of a resource recovery system in one embodiment of the present application; Figure 2 is a process flow chart of a clinker burning system in some embodiments of the present application; Figure 3 is a schematic diagram of the cross-sectional structure of a kiln head sealing device in some embodiments of the present application; Figure 4 is a schematic diagram of the cross-sectional structure of a kiln tail sealing device in some embodiments of the present application; Figure 5 is a process flow chart of a raw material purification system in some embodiments of the present application; The marks in the attached drawings are: 1. clinker burning system, 11. pressure reamer, 12. first preheater, 13. preheater group, 131. second preheater, 132. third preheater, 133. fourth preheater, 134. fifth preheater, 14. ammonia storage tank, 15. decomposition furnace, 16. rotary kiln, 161. kiln tail burner, 162. kiln tail sealing device, 1621. pressing seal rotating end, 1622. contact ring, 1623. sealing chamber, 1624. kiln tail circulating gas inlet, 1625. isolation cover, 1626. friction pair, 16 27. Press and seal the fixed end, 163. Kiln head burner, 164. Kiln head sealing device, 1641. Cold air sleeve, 1642. Circulating gas outlet, 1643. Sealing cover, 1644. Kiln head circulating gas inlet, 1645. Isolation chamber, 1646. Sealing sheet, 1647. Friction ring, 165. Kiln head cover, 17. Grate cooler, 171. First cooling zone, 172. Second cooling zone, 173. Third cooling zone, 18. Air cannon, 19. Smoke chamber, 2. First SCR device, 3. Clinker storage, 4. First heat exchanger, 41. Ash cleaning device. DETAILED DESCRIPTION

[0029] The following is an explanation of the implementation of the present application by specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the information disclosed in the present application. The present application can also be implemented or applied through other different specific implementations, and the details in the present application can also be modified or changed in various ways according to different viewpoints and application systems without departing from the spirit of the present application. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0030] The following is a detailed description of the embodiments of the present application with reference to the accompanying drawings so that those skilled in the art can easily implement the present application. The present application can be embodied in a variety of different forms and is not limited to the embodiments described herein.

[0031] In the representations of the present application, the representations with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics represented in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. Moreover, the represented specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples represented in the present application and the features of the different embodiments or examples, unless they contradict each other.

[0032] In addition, the terms "first" and "second" are only used to indicate the target, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the representation of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0033] Throughout the specification, when a device is said to be "connected" to another device, this includes not only the case of "direct connection" but also the case of "indirect connection" by placing other elements therebetween. In addition, when a device is said to "include" a certain component, unless otherwise stated, it does not exclude other components, but means that other components may be included.

[0034] The following is combined with Figure 1 -Attached Figure 5 , further details of this application are given.

[0035] The embodiments of the present application disclose a cement production line resource utilization system and method.

[0036] A cement production line resource system, reference Figure 1 As shown, the system or device includes the following pipeline connections: a circulating gas conveying pipeline, a combustion conveying pipeline, an oxygen conveying pipeline and a methanol mixing pipeline. The circulating gas conveying pipeline is the main pipeline of this system. In the process of producing cement clinker by the cement production line, the carbon dioxide and nitrogen oxides generated are circulated and transported in the circulating gas conveying pipeline with the circulating gas. The combustion conveying pipeline and the methanol mixing pipeline are both connected to the circulating gas conveying pipeline. The combustion conveying pipeline provides mixed transportation of coal powder and oxygen. The oxygen conveying pipeline can separate oxygen from the air and cooperate with the combustion conveying pipeline to ensure sufficient raw materials for oxygen-enriched combustion during cement production. The methanol mixing pipeline produces methanol, and methanol is used to remove nitrogen oxides generated by combustion.

[0037] Among them, the circulating gas transportation pipeline includes a clinker burning system 1, a first heat exchanger 4, a first SCR device 2, a booster fan, a dust collector, a circulating fan and a dehydration device which are connected in sequence; the clinker burning system 1 is provided with a feed end, a combustion end and an exhaust end, the combustion end is a kiln tail burner and a kiln head burner, the raw material enters the clinker burning system 1 from the feed end, and is sintered into cement clinker through the combustion end, and the sintering of cement clinker produces carbon dioxide and nitrogen oxides which are mixed into the circulating gas, the circulating gas is transported from the exhaust end to the dehydration device in sequence, and the nitrogen oxides in the circulating gas are removed when it is transported to the SCR device 2.

[0038] At the same time, after the dehydration device removes water from the circulating gas, a part of it is transported back to the clinker burning system 1 to form the recycling of the circulating gas, and the other part of the circulating gas enters other pipelines for auxiliary circulation.

[0039] Among them, the combustion and conveying pipeline is connected to the pipeline between the dehydration device and the clinker burning system 1, specifically located near the discharge end, including a conveying fan, an air compressor device, a ash cleaning system, a second heat exchanger, a sealing system and a pulverized coal conveying system; the second heat exchanger, the conveying fan, the sealing system and the pulverized coal conveying system are connected to the pipeline behind the dehydration device, that is, the pipeline connection away from the end of the first SCR device 2. Since there is moisture in the continuously added raw materials, the combustion will produce moisture. The dehydration device is used to avoid more and more moisture in the circulating gas. The sealing system provides a slight positive pressure. When the clinker burning system 1 is burning, the circulating gas circulates stably to avoid air leakage.

[0040] The air compressor device is connected to the second heat exchanger, which reduces the temperature of the circulating gas. The cleaning system is connected to the air compressor device to provide a cleaning effect to prevent dust in the circulating gas from adhering to the air compressor device and gradually accumulating, making the air compressor device easy to be damaged. The other end of the conveying fan and the coal powder conveying system is connected to the combustion end. The conveying fan provides air pressure supply so that the circulating gas can be directly transported to the combustion end, and the coal powder conveying system can mix coal powder into the circulating gas. Coal powder provides fuel supply for cement sintering.

[0041] The methanol mixing pipeline is initially connected to the pipeline between the circulating fan and the dehydration device, and is sequentially connected to the raw gas purification system, the methanol synthesis device, the power-to-gas device, the methanol fuel cell and the methanol storage tank; a part of the circulating gas enters the raw gas purification system, and the raw gas purification system can purify the circulating gas to form clean raw gas, and transport it to the methanol synthesis device. The purge gas generated by the methanol synthesis device enters the combustion end, and the synthesized methanol enters the methanol storage tank; the power-to-gas device adds water, which can be decomposed to form hydrogen and oxygen, and the oxygen is connected to the oxygen transmission pipeline. The hydrogen enters the methanol synthesis device to synthesize methanol and is stored in the methanol storage tank; the methanol storage tank is connected to the first SCR device 2 and the combustion end, and transports methanol. After the first SCR device 2 is added with methanol, a methanol catalyst is provided in the first SCR device 2 to reduce most of the nitrogen oxides. The combustion end provides auxiliary combustion after the addition of methanol. Water vapor and carbon dioxide are generated during combustion and added to the circulating gas for carbon dioxide recycling.

[0042] The methanol synthesis device is also connected to a methanol fuel cell.

[0043] The oxygen delivery pipeline includes an air separation oxygen generator and an oxygen storage tank; the air separation oxygen generator extracts air to separate oxygen, and the oxygen is provided through five pipelines for delivery.

[0044] The first pipeline is connected to the oxygen storage tank, so that oxygen can be stored in the oxygen storage tank for use as backup oxygen. At the same time, the oxygen decomposed by the electric-to-gas device is also connected to the oxygen storage tank through the pipeline to avoid waste of oxygen.

[0045] The second pipeline is connected to the kiln tail burner 161 at the combustion end to provide the oxygen supply required for oxygen-enriched combustion in the clinker burning system 1; the third pipeline is connected to the kiln head burner 163, and mixes the oxygen with the circulating gas through the conveying fan and then conveys it to the combustion end; the fourth pipeline is connected to the discharge end to mix with the circulating gas at the discharge end and convey it toward the combustion end; the fifth pipeline is connected to the methanol fuel cell.

[0046] Specifically, raw materials enter the feed end of the clinker burning system 1, and oxygen-enriched combustion is carried out through the combustion end to sinter the raw materials into cement clinker. The carbon dioxide and nitrogen oxides generated during the combustion process at the combustion end enter the circulating gas conveying pipeline through the circulating gas for circulation. Most of the nitrogen oxides are removed by the first SCR device 2. When passing through the circulating fan, a part is separated and enters the methanol mixing pipeline to generate methanol. Methanol is added to the first SCR device 2 to provide nitrogen oxide removal. At the same time, the oxygen conveying pipeline uses air to separate oxygen to provide oxygen supply for oxygen-enriched combustion. After the dehydration device removes water from the circulating gas, the combustion conveying pipeline cooperates with the circulating gas for transportation, and transports coal powder, oxygen and carbon dioxide to the combustion end at the same time, so that the combustion end can obtain stable oxygen-enriched combustion.

[0047] When the raw material is sintered into shape, the gas generated by the oxygen-rich combustion continues to circulate in the circulating gas pipeline. After the nitrogen oxides are removed, the carbon dioxide is recycled to reduce the emission of carbon dioxide. The hydrogen formed by the decomposition of oxygen can participate in the synthesis of methanol. After the methanol reduces the nitrogen oxides, it can also provide auxiliary combustion. The sealing system is used to close the air leakage generated during the combustion process to reduce the entry of outside air, thereby achieving the comprehensive utilization of technical energy and materials and reducing the operating costs.

[0048] For further reference, Figure 2 As shown, the clinker burning system 1 includes: a grate cooler 17, a rotary kiln 16, a kiln head burner 163, a kiln head cover 165, a smoke chamber 19, a decomposition furnace 15, a kiln tail burner 161, a preheater group 13, a pressure reamer 11 and an air cannon 18; wherein the grate cooler 17 is divided into a first cooling zone 171, a second cooling zone 172 and a third cooling zone 173; the preheater group 13 includes a first preheater 12, a second preheater 131, a third preheater 132, a fourth preheater 133 and a fifth preheater 134 connected in sequence, and the pressure reamer 11 is connected The connecting pipe between the second preheater 131 and the first preheater 12, the pressure reamer 11 is the feed end of the raw meal, the raw meal is input into the system through the pressure reamer 11 at the connecting pipe from the second stage preheater to the first stage preheater, and heat exchanges with the circulating gas rich in high concentration of carbon dioxide in the pipeline to avoid energy loss, the circulating gas enters the first stage preheater, the first preheater 12 is the exhaust end, the circulating gas is transported to the first heat exchanger 4, and after the temperature of the circulating gas is reduced by the first heat exchanger 4, it is transported to the first SCR device 2 for nitrogen oxide treatment.

[0049] The fifth preheater 134 is connected to the decomposition furnace 15, and the kiln tail burner 161 is arranged on the decomposition furnace 15. The raw material enters the decomposition furnace 15 after heat exchange with the circulating gas in the second to fourth preheaters in sequence. The decomposition furnace 15 is connected to the smoke chamber 19, and the smoke chamber 19 is connected to one end of the rotary kiln 16. The raw material enters the fifth preheater after pre-decomposition in the decomposition furnace 15, and enters the smoke chamber 19 after being collected by the fifth preheater, and then enters the rotary kiln 16. The other end of the rotary kiln 16 is connected to the kiln head cover 165 and the first cooling zone 171 of the grate cooler 17. After the rotary kiln 16 burns the clinker, it enters the first cooling zone 171. After passing through the first cooling zone 171, the second cooling zone 172 and the third cooling zone 173, the clinker is completely cooled. The third cooling zone 173 is connected to the clinker warehouse 3, and the clinker finally enters the clinker warehouse 3 for collection.

[0050] The kiln head burner 163 and the kiln tail burner 161 together form a combustion end, and the oxygen delivery pipelines are connected to the kiln head burner 163 and the kiln tail burner 161. At the same time, the methanol storage tank is also connected to the kiln tail burner 161, that is, the kiln tail burner 161 is connected to the pipelines of methanol, oxygen, and circulating gas. The exhaust gas produced by the formaldehyde synthesis device is connected to the decomposition furnace 15, and part of the combustibles in the exhaust gas are used as fuel. The water vapor in the exhaust gas can reduce the decomposition temperature of calcium carbonate in the decomposition furnace 15 under the high partial pressure of carbon dioxide, which can save fuel and reduce the temperature and prevent equipment from scaling.

[0051] In some embodiments, reference Figure 1 As shown, the sealing system also includes a kiln head sealing device 164, a kiln tail sealing device 162, a first heat exchanger 4 dust cleaning device 41 and improved inspection doors, valves, holes, covers, etc. at various parts of the system, and a piping system connecting various sealing points; the kiln head sealing device 164 is installed at the kiln head of the rotary kiln 16, and the kiln tail sealing device 162 is installed at the kiln tail of the rotary kiln 16. The kiln head sealing device 164 and the kiln tail sealing device 162 respectively seal the kiln head of the rotary kiln 16 to prevent air from entering the system during oxygen-enriched combustion of raw materials.

[0052] For further reference, Figure 3 As shown, the kiln head sealing device 164 adopts a double-layer fish scale sealing structure; a plurality of sealing sheets 1646 are stacked to form two layers of fish scale-shaped annular cover bodies, one end of which is fixed on the sealing cover 1643, and the other end is pressed on the friction ring 1647, the friction ring 1647 is fixed on the outer wall of the rotary kiln 16, the sealing cover 1643 is fixed on the kiln head cover 165, and the sealing cover 1643 is provided with two kiln head circulating gas inlets 1644 and circulating gas outlets 1642, the two kiln head circulating gas inlets 1644 are kiln head circulating gas inlet 1 and kiln head circulating gas inlet 2 respectively; the two layers of sealing sheets 1646, the friction ring 1647 and the sealing cover 1643 together form an isolation chamber 1645.

[0053] In the kiln head sealing device 164, the circulating gas enters the isolation chamber 1645 from the kiln head circulating gas inlet, and maintains a slight positive pressure in the isolation chamber 1645. Part of the circulating gas passes through the gap between the sealing sheets 1646 and enters the external air, so that the external air cannot enter the isolation chamber 1645.

[0054] The circulating air entering from the kiln head circulating air inlet 2 enters the cold air jacket 1641 to cool the kiln head, and most of it is discharged through the circulating air outlet 1642, and a small part enters the system through the kiln head cover 165, that is, the kiln head sealing device 164 isolates the outside air from entering the system.

[0055] Further, refer to Figure 4 As shown, the kiln tail sealing device 162 adopts a double-layer sealing structure of compression sealing and fish scale sealing.

[0056] The isolation cover 1625 is fixed on the side wall of the smoke chamber 19. One end of the fish-scale annular cover body formed by stacking a number of fish scales is fixed on the isolation cover 1625, and the other end is pressed on the contact ring 1622. The contact ring 1622 is fixed on the compression sealing rotating end 1621.

[0057] The isolation cover 1625, the fish scale sheet, and the contact ring 1622 constitute a fish scale sealing structure. The contact part of the compression seal fixed end 1627 and the compression seal rotating end 1621 forms a friction pair 1626 to constitute a compression seal structure. The isolation cover 1625, the fish scale sheet, the contact ring 1622, the compression seal fixed end 1627 and the compression seal rotating end 1621 together form a sealing cavity 1623.

[0058] In the kiln tail sealing device 162, the compression sealing rotating end 1621 rotates with the rotary kiln 16 to form a double sealing structure of fish scales and friction pairs 1626. The circulating gas enters the sealing chamber 1623 from the kiln tail circulating gas inlet 1624 and maintains a slight positive pressure in the sealing chamber 1623. Part of the circulating gas passes through the gaps between the sealing plates 1646 and enters the external air, and part of the circulating gas passes through the gaps between the friction pairs 1626 of the compression sealing structure and enters the smoke chamber 19. The function is to prevent external air from entering the sealing chamber 1623, that is, the kiln tail sealing device 162 isolates the external air from entering the system.

[0059] In some embodiments, reference Figure 5 As shown, the raw gas purification system includes an absorption tower, a second SCR device, a pressure swing adsorption device, a fan, a chimney, a hot air device, a regeneration tower, and a sulfur recovery device; the absorption tower is equipped with activated carbon, which is connected to the second SCR device and the regeneration tower respectively. After the activated carbon in the absorption tower adsorbs sulfides in the circulating gas, the circulating gas is mixed with methanol from the methanol storage tank and homogenized before entering the second SCR device. The regeneration tower is respectively connected to the hot air device and the sulfur recovery device. The hot air device is connected to one methanol and one oxygen, and transported to the regeneration tower; the second SCR device is respectively connected to the pressure swing adsorption device and the chimney, and the pressure swing adsorption device is connected to the methanol synthesis device. A methanol catalyst is arranged in the second SCR device. The circulating gas and the methanol mixed gas are catalytically reduced to all nitrogen oxides under the action of the methanol catalyst and then enter the methanol synthesis device after passing through the fan.

[0060] The raw gas purification system is used to absorb the sulfides in the circulating gas. The remaining circulating gas and methanol mixed gas catalytically reduce all nitrogen oxides under the action of methanol catalyst and then enter the methanol synthesis unit through the blower to provide stable pure raw gas for the methanol synthesis unit.

[0061] Among them, activated carbon is divided into regenerated activated carbon, sulfur-rich activated carbon, and newly added activated carbon for supplementation.

[0062] The waste gas generated by the absorption tower is recovered through the sulfur recovery device.

[0063] The raw gas purification system can purify part of the circulating gas separated from the circulating fan. The reduced clean raw gas can participate in the synthesis of methanol, and the generated methanol can participate in the reduction and removal of nitrogen oxides in the circulating gas, thereby rationalizing resource allocation and utilization.

[0064] In some embodiments, reference Figure 1 As shown, it also includes wind power and photovoltaic power generation systems, which are respectively connected to the power-to-gas device, the air separation oxygen production device and the methanol synthesis device, and provide power supply; The methanol fuel cell is connected to the methanol storage tank and the air separation oxygen production device, so that the methanol in the methanol storage tank and the oxygen in the air separation oxygen production device can generate electricity through the methanol fuel cell, and the electricity is then supplied to the power-to-gas device, the methanol synthesis device, and the air separation oxygen production device.

[0065] Wind and photovoltaic power generation systems and methanol fuel cells provide the electricity required for air separation oxygen production equipment, power-to-gas equipment and methanol synthesis equipment. By flexibly scheduling the output plans and energy distribution relationships of each device, the electricity utilization of methanol fuel cells and wind and photovoltaic power generation systems is scheduled based on peak and valley time periods and wind and solar intensity. Wind and photovoltaic power generation are used first, and the carbon dioxide produced by the methanol fuel cell is transported to the methanol synthesis unit for reuse in synthesizing methanol, so as to achieve the effect of rational utilization of resources.

[0066] The wind and photovoltaic power generation systems can provide their own electricity supply, so that the air separation oxygen production unit, methanol synthesis unit, and power-to-gas unit can all be supplied with electricity, reducing the transmission of external electricity and making rational use of circulating resources. At the same time, methanol fuel cells can make up for the insufficient power supply in the wind and photovoltaic power generation systems, further improving the utilization rate of resources.

[0067] In some embodiments, reference Figure 2 As shown, a dust cleaning device 41 is provided in the first heat exchanger 4. The dust cleaning device 41 can adopt a vibration mode, such as a vibration motor, to utilize the vibration effect to shake and scatter the attached dust.

[0068] When the first heat exchanger 4 cools down and exchanges heat for the circulating gas, due to the presence of dust in the raw material, the water vapor generated by the combustion of methanol is difficult to fully adhere to it, and the dust will stick to the first heat exchanger 4. When the dust accumulates too much, it will easily lead to a decrease in the heat exchange effect. Therefore, a cleaning device 41 is provided to clean the attached dust to ensure the stability of the heat exchange.

[0069] This application also provides a cement production line resource method, referring to Figure 1 and Figure 2 As shown, the cement production resource system applied in the above embodiment includes the following steps: When the clinker burning system 1 sintered cement clinker, carbon dioxide and nitrogen oxides were generated, and the circulating gas rich in high concentration of carbon dioxide entered the circulating gas transmission pipeline, passed through the first heat exchanger 4, and the first heat exchanger 4 lowered the circulating gas temperature and then mixed it with methanol from the methanol storage tank and homogenized it before entering the first SCR device 2.

[0070] A methanol catalyst is provided in the first SCR device 2. The circulating gas and the methanol mixed gas catalytically reduce most of the nitrogen oxides under the action of the methanol catalyst, and then enter the circulating fan after being dusted by the booster fan and the dust collector. The SCR device 2 uses the methanol mixed gas and the methanol catalyst to reduce the nitrogen oxides, which can provide a more environmentally friendly removal effect.

[0071] The circulating gas is divided into two routes after passing through the circulating fan: the first circulating gas enters the raw gas purification system of the methanol mixing pipeline, and forms pure raw gas after purification. The pure raw gas enters the methanol synthesis unit to participate in methanol synthesis; the second circulating gas continues to go through the circulating gas conveying pipeline to the dehydration device, and the dehydration device removes part of the water and then returns to the clinker burning system 1 for continued recycling.

[0072] In the raw gas purification system of the methanol mixing pipeline, the circulating gas first passes through the absorption tower. After the activated carbon in the absorption tower adsorbs the sulfide in the circulating gas, the circulating gas is mixed with the methanol from the methanol storage tank and homogenized before entering the second SCR device. The second SCR device is provided with a methanol catalyst. The circulating gas and methanol mixed gas are catalytically reduced to all nitrogen oxides under the action of the methanol catalyst and then enter the methanol synthesis device to generate purge gas and methanol. The purge gas enters the combustion end, and the methanol enters the methanol storage tank. After the circulating gas has part of its water removed by the dehydration device, it enters the combustion transmission pipeline and the clinker burning system 1, and is divided into four routes in the combustion transmission pipeline: the first route is lowered in temperature by the second heat exchanger and then goes to the air compressor device and then to the ash cleaning system; the second route goes to the conveying fan; the third route goes to the coal powder conveying system, and the fourth route goes to the sealing system; the transmission to the clinker burning system 1 is divided into two routes, the first route is mixed with the high-concentration oxygen from the air separation oxygen production device and then goes to the first cooling zone 171 of the grate cooler 17; the second route goes to the second cooling zone 172 of the grate cooler 17, thereby realizing the circulating gas of carbon dioxide and the removal of nitrogen oxides.

[0073] Furthermore, the raw meal is introduced into the system through the pressure reamer 11 at the connecting pipe from the second stage preheater to the first stage preheater, and exchanges heat with the circulating gas rich in high concentration of carbon dioxide in the pipe, and enters the first stage preheater with the circulating gas.

[0074] When the pressure reamer 11 is working, the interior is filled with raw material, and the raw material is pushed into the system by the spiral blades, that is, the air is isolated from entering the system in the form of a material seal.

[0075] The raw meal in the circulating gas is collected by the first-stage preheater and enters the connecting pipe between the third-stage preheater and the second-stage preheater, and enters the second-stage preheater after heat exchange with the circulating gas.

[0076] The raw meal is heat exchanged with the circulating gas in the second to fourth stage preheaters in sequence and then enters the decomposition furnace 15. The decomposition furnace 15 contains methanol transported from the methanol storage tank to accelerate the decomposition efficiency.

[0077] The raw material is pre-decomposed in the decomposition furnace 15 and then enters the fifth-stage preheater. After being collected by the fifth-stage preheater, it enters the smoke chamber 19 and then enters the rotary kiln 16. After being burnt into mature material in the rotary kiln 16, it enters the first cooling zone 171 of the grate cooler 17.

[0078] The clinker is cooled to the required temperature in the first cooling zone 171, the second cooling zone 172 and the third cooling zone 173 of the grate cooler 17 in sequence and then enters the clinker storage 3 for storage.

[0079] Furthermore, the temperature of the circulating gas rich in high-concentration carbon dioxide is 250-300°C, and the temperature after leaving the first stage preheater through the first heat exchanger 4 is 200-250°C, and the dust concentration is greatly reduced. After being mixed and homogenized with the methanol from the methanol storage tank, it enters the first SCR device 2. A methanol catalyst is provided in the first SCR device 2. The circulating gas and methanol mixed gas catalytically reduce most of the nitrogen oxides under the action of the methanol catalyst. The nitrogen oxide content in the circulating gas leaving the first SCR device 2 is less than 50mg / m3. After the booster fan and the dust collector remove the dust, the dust concentration is less than 10mg / m3, and then passes through the circulating fan.

[0080] After the circulating gas passes through the circulating fan, the dry basis concentration of carbon dioxide is greater than 80%, and it is divided into two routes: the first circulating gas enters the methanol synthesis unit after being purified by the raw gas purification system; the second circulating gas continues to be recycled after part of the water is removed by the dehydration device.

[0081] In the raw gas purification system, the circulating gas first passes through the absorption tower. The activated carbon in the absorption tower adsorbs the sulfide in the circulating gas, and then it is mixed and homogenized with the methanol from the methanol storage tank and enters the second SCR device. The second SCR device is equipped with a methanol catalyst. Methanol catalytically reduces all nitrogen oxides in the circulating gas under the action of the methanol catalyst, and then enters the methanol synthesis device through the fan.

[0082] The circulating gas is divided into six routes after some water is removed by the dehydration device. The first route is to go to the air compressor device and then to the ash cleaning system after the temperature is reduced by the second heat exchanger; the second route is to the conveying fan; the third route is to the coal powder conveying system, the fourth route is to the sealing system, the fifth route is mixed with the high-concentration oxygen from the air separation oxygen production device and then goes to the first cooling zone 171 of the grate cooler 17; the sixth route is to go to the second cooling zone 172 of the grate cooler 17.

[0083] The compressed circulating air after passing through the air compressor device is used as the air source of the cleaning system, including the air cannon 18 cleaning, the dust collector pulse cleaning device 41 cleaning and the first heat exchanger 4 cleaning device 41.

[0084] After passing through the conveying fan, the circulating gas is divided into two paths: the first path is mixed with the high-concentration oxygen from the air separation oxygen production device and transported to the kiln tail burner 161; the second path is mixed with the high-concentration oxygen from the air separation oxygen production device as primary air and transported to the kiln head burner 163. Different combustion flame forms can be obtained by adjusting the ratio of circulating gas and high-concentration oxygen.

[0085] The pulverized coal conveying system utilizes circulating gas to pneumatically convey the pulverized coal to the kiln tail burner 161 and the kiln head burner 163 respectively.

[0086] The circulating air entering the first cooling zone 171 of the grate cooler 17 exchanges heat with the clinker from the rotary kiln 16 and then enters the kiln head hood 165. The gas temperature in the kiln head hood 165 is 950-1250°C. Part of it enters the rotary kiln 16 as secondary air, and part of it enters the decomposition furnace 15 as tertiary air; the circulating air entering the second cooling zone 172 of the grate cooler 17 exchanges heat with the clinker from the first cooling zone 171 and has a temperature of 400-500°C, and then enters the outlet of the decomposition furnace 15 for cooling and air replenishment; in the third cooling zone 173 of the grate cooler 17, the air and the clinker from the second cooling zone 172 are heat exchanged to become hot air at 200-250°C, and the hot air goes to the raw material drying system and the coal mill drying system respectively.

[0087] During oxygen-enriched combustion, since the raw meal is in a high carbon dioxide atmosphere, to achieve the same decomposition rate as under air combustion conditions, the decomposition temperature of the raw meal in the decomposition furnace 15 must be increased by 80-100°C. To avoid equipment crusting, the decomposition furnace 15 is provided with a kiln tail burner 161 with a pre-combustion chamber structure. The circulating gas carries the pulverized coal into the pre-combustion chamber first, and the excess coefficient of oxygen in the pre-combustion chamber is 0.6. The pulverized coal is first gasified and pyrolyzed into combustibles such as carbon monoxide, hydrogen and methane in the pre-combustion chamber, and then enters the decomposition furnace 15, and a part of the tertiary air, that is, the tertiary air split air is sprayed into the decomposition furnace 15 in an annular shape, which holds the combustibles for rapid combustion and avoids high-temperature crusting on the side wall of the decomposition furnace 15.

[0088] The purge gas of the methanol synthesis unit is introduced into the decomposition furnace 15. Function 1: Part of the combustibles in the purge gas are used as fuel; Function 2: The water vapor in the purge gas can reduce the temperature of calcium carbonate decomposition in the decomposition furnace 15 under high partial pressure of carbon dioxide, which can save fuel and reduce temperature, and prevent equipment from crusting.

[0089] Furthermore, in the kiln head sealing device 164, the circulating air is passed into the isolation chamber 1645 from the kiln head circulating air inlet 1, and the isolation chamber 1645 is kept at a slight positive pressure of 5Pa, and part of the circulating air passes through the gap between the sealing sheets 1646 and enters the outside air, which prevents the outside air from entering the isolation chamber 1645. After the circulating air entering from the kiln head circulating air inlet 2 enters the cold air jacket 1641 to cool the kiln head, most of it is discharged through the circulating air outlet 1642, and a small part enters the system through the kiln head cover 165, that is, the kiln head sealing device 164 isolates the outside air from entering the system.

[0090] In the kiln tail sealing device 162, the compression sealing rotating end 1621 rotates with the rotary kiln 16 to form a double sealing structure of fish scales and friction pairs 1626. The circulating gas enters the sealing chamber 1623 from the kiln tail circulating gas inlet 1624, and maintains a slight positive pressure of 5Pa in the sealing chamber 1623. Part of the circulating gas passes through the gaps between the sealing plates 1646 and enters the external air, and part of the circulating gas passes through the gaps between the friction pairs 1626 of the compression sealing structure and enters the smoke chamber 19. The function is to prevent external air from entering the sealing chamber 1623, that is, the kiln tail sealing device 162 isolates the external air from entering the system.

[0091] Furthermore, the wind and photovoltaic power generation systems and methanol fuel cells provide the electricity required for the air separation oxygen production unit, the power-to-gas unit and the methanol synthesis unit; the oxygen and gas production systems flexibly schedule the output plans and energy distribution relationships of each device; the electricity utilization of the methanol fuel cells and wind and photovoltaic power generation systems is scheduled based on peak and valley time periods and wind and solar intensity, with wind and photovoltaic power generation being given priority; the carbon dioxide produced by the methanol fuel cell is transported to the methanol synthesis unit for reuse.

[0092] The oxygen produced by the air separation oxygen production device is stored in an oxygen storage tank or directly transported to the kiln head burner 163, the kiln tail burner 161, and the first cooling zone 171 of the grate cooler 17 for use. The power-to-gas device electrolyzes water to generate oxygen and hydrogen, of which the oxygen is stored in an oxygen storage tank or directly transported to the kiln head burner 163, the kiln tail burner 161, and the first cooling zone 171 of the grate cooler 17 for use. Hydrogen and the high-concentration carbon dioxide purified from the carbon dioxide capture system undergo a methanogenic reaction under the action of a catalyst to generate methanol, which is stored in a methanol storage tank.

[0093] The oxygen storage tank realizes the cross-time use of oxygen. When the output of wind power and photovoltaic power generation system is large, their electric energy is supplied to the air separation oxygen production device and the power-to-gas device to produce oxygen. Part of the produced oxygen is transmitted to the kiln head burner 163, the kiln tail burner 161, and the first cooling zone 171 of the grate cooler 17 for use, and the surplus oxygen enters the oxygen storage tank for storage. When the output of wind power and photovoltaic power generation system is small, the oxygen produced by the air separation oxygen production device and the power-to-gas device supplied by their electric energy cannot meet the oxygen-rich operation demand of the system, the oxygen difference is supplied by the oxygen storage tank. When there is still a difference, the external power grid is enabled to supplement the power supply for oxygen production.

[0094] The methanol storage tank enables the cross-time use of methanol. The uses of the methanol stored in the methanol storage tank are as follows: Use 1: As an auxiliary fuel, it is stably supplied to the kiln tail burner 161 to reduce coal powder consumption; Use 2: As a reducing agent, it is transported to the first SCR device 2 for denitrification; Use 3: As a raw material for methanol fuel cells; Use 4: As a reducing agent, it is transported to the second SCR device for secondary denitrification to ensure the cleanliness of the raw gas entering the methanol synthesis device and avoid catalyst poisoning; Use 5: As fuel for the hot air device.

[0095] The embodiments of this specific implementation are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. The same components are represented by the same figure marks. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A cement production line resource recovery system, characterized in that: A system or device comprising the following pipeline connections: a circulating gas delivery pipeline, a combustion delivery pipeline, an oxygen delivery pipeline and a methanol mixing pipeline, wherein the combustion delivery pipeline and the methanol mixing pipeline are both connected to the circulating gas delivery pipeline; The circulating gas conveying pipeline is sequentially connected to the clinker burning system (1), the first heat exchanger (4), the first SCR device (2), the booster fan, the dust collector, the circulating fan and the dehydration device; the clinker burning system (1) is provided with a feed end, a combustion end and an exhaust end, the combustion end being a kiln tail burner (161) and a kiln head burner (163); the carbon dioxide generated by the sintering of cement clinker is mixed with the circulating gas; the circulating gas is conveyed from the exhaust end to the dehydration device in sequence, the dehydration device removes water from the circulating gas, and then conveys it back to the clinker burning system (1) to realize the recycling of the circulating gas; The combustion and conveying pipeline is connected to the pipeline between the dewatering device and the clinker burning system (1), and includes a conveying fan, an air compressor device, a ash cleaning system, a second heat exchanger, a sealing system and a pulverized coal conveying system; the second heat exchanger, the conveying fan, the sealing system and the pulverized coal conveying system are connected to the pipeline behind the dewatering device; the air compressor device is connected to the second heat exchanger, and the ash cleaning system is connected to the air compressor device; the conveying fan and the other end of the pulverized coal conveying system are connected to the combustion end; The methanol mixing pipeline is initially connected to the pipeline between the circulating fan and the water removal device, and is sequentially connected to the raw gas purification system, the methanol synthesis device, the power-to-gas device, the methanol fuel cell and the methanol storage tank; a part of the circulating gas enters the raw gas purification system, is purified to form clean raw gas, and is transported to the methanol synthesis device, and the synthesis purge gas of the methanol synthesis device enters the combustion end; water is added to the power-to-gas device to decompose to form hydrogen and oxygen, the oxygen is connected to the oxygen transmission pipeline, the hydrogen enters the methanol synthesis device to synthesize methanol, and is stored in the methanol storage tank; the methanol storage tank is connected to the first SCR device (2), the methanol fuel cell and the combustion end, and transports methanol; The oxygen delivery pipeline comprises an air separation oxygen production device and an oxygen storage tank; the air separation oxygen production device extracts air to separate oxygen, and separates the oxygen into five pipelines for delivery; the first pipeline is connected to the oxygen storage tank; the second pipeline is connected to the kiln tail burner (161); the third pipeline is connected to the kiln head burner (163); the fourth pipeline is connected to the discharge end; and the fifth pipeline is connected to the methanol fuel cell.

2. A cement production line resource recovery system according to claim 1, characterized in that: The clinker burning system (1) further comprises: a grate cooler (17), a rotary kiln (16), a kiln head cover (165), a smoke chamber (19), a decomposition furnace (15), a preheater group (13), a pressure reamer (11) and an air cannon (18); wherein the grate cooler (17) is divided into a first cooling zone (171), a second cooling zone (172) and a third cooling zone (173); the pressure reamer (11) is connected to a connecting pipe between the second preheater (131) and the first preheater (12); the preheater group (13) comprises a connecting pipe connected in sequence to the first preheater (131); The rotary kiln (16) is provided with a first preheater (12), a second preheater (131), a third preheater (132), a fourth preheater (133) and a fifth preheater (134); the fifth preheater (134) is connected to the decomposition furnace (15); the kiln tail burner (161) is arranged on the decomposition furnace (15); the decomposition furnace (15) is connected to the smoke chamber (19); the smoke chamber (19) is connected to one end of the rotary kiln (16); and the other end of the rotary kiln (16) is connected to the kiln head cover (165) and the first cooling zone (171) of the grate cooler (17).

3. A cement production line resource recovery system according to claim 2, characterized in that: The sealing system comprises: a kiln head sealing device (164) and a kiln tail sealing device (162); the kiln head sealing device (164) is installed at the kiln head of the rotary kiln (16), and the kiln tail sealing device (162) is installed at the kiln tail of the rotary kiln (16).

4. A cement production line resource recovery system according to claim 3, characterized in that: The kiln head sealing device (164) adopts a double-layer fish scale sealing structure; one end of the fish scale annular cover body formed by stacking a plurality of sealing sheets (1646) is fixed to the sealing cover (1643) and the other end is pressed to the friction ring (1647), and the friction ring (1647) is fixed to the outer wall of the rotary kiln (16); the sealing cover (1643) is fixed to the kiln head cover (165), and the sealing cover (1643) is provided with two kiln head circulating air inlets (1644) and a circulating air outlet (1642); the two layers of sealing sheets (1646), the friction ring (1647) and the sealing cover (1643) together form an isolation chamber (1645).

5. A cement production line resource recovery system according to claim 3, characterized in that: The kiln tail sealing device (162) adopts a double-layer sealing structure of a compression seal and a fish scale seal; the isolation cover (1625) is fixed on the side wall of the smoke chamber (19); one end of a fish scale-shaped annular cover body formed by stacking a plurality of fish scales is fixed on the isolation cover (1625), and the other end is pressed on a contact ring (1622); the contact ring (1622) is fixed on a compression seal rotating end (1621); the isolation cover (1625), the fish scales, and the contact ring (1622) constitute a fish scale seal structure; the contact part of the compression seal fixed end (1627) and the compression seal rotating end (1621) forms a friction pair (1626), constituting a compression seal structure; the isolation cover (1625), the fish scales, the contact ring (1622), the compression seal fixed end (1627), and the compression seal rotating end (1621) together enclose a sealing cavity (1623).

6. A cement production line resource recovery system according to claim 1, characterized in that: The raw gas purification system includes an absorption tower, a second SCR device, a pressure swing adsorption device, a fan, a chimney, a hot air device, a regeneration tower, and a sulfur recovery device; activated carbon is provided in the absorption tower, and the absorption tower is respectively connected to the second SCR device and the regeneration tower; the regeneration tower is respectively connected to the hot air device and the sulfur recovery device; the second SCR device is respectively connected to the pressure swing adsorption device and the chimney, and the pressure swing adsorption device is connected to the methanol synthesis device; wherein, when the air separation oxygen production device separates oxygen, one path is separated to the hot air device.

7. A cement production line resource recovery system according to claim 1, characterized in that: It also includes wind power and photovoltaic power generation systems, which are respectively connected to the power-to-gas device, the air separation oxygen production device and the methanol synthesis device, and provide power supply; the wind power and photovoltaic power generation systems supply electricity to the methanol fuel cell for power storage.

8. A cement production line resource recovery system according to claim 1, characterized in that: A dust cleaning device (41) is provided in the first heat exchanger (4).

9. A cement production line resource utilization method, characterized in that: The cement production line resource recovery system applied to claim 2 comprises the following steps: When the clinker burning system (1) sintered and formed cement clinker, carbon dioxide and nitrogen oxides were generated, and the circulating gas rich in high concentration of carbon dioxide entered the circulating gas transmission pipeline, passed through the first heat exchanger (4), was mixed and homogenized with methanol from the methanol storage tank, and then entered the first SCR device (2); A methanol catalyst is provided in the first SCR device (2). The circulating gas and methanol mixed gas are catalytically reduced to most of the nitrogen oxides under the action of the methanol catalyst, and then pass through the booster fan and the dust collector for dust removal before entering the circulating fan; After passing through the circulating fan, the circulating gas is divided into two routes: the first circulating gas enters the raw gas purification system of the methanol mixing pipeline, and enters the methanol synthesis unit after purification; the second circulating gas continues to go through the circulating gas transmission pipeline to the dehydration device, and the dehydration device removes part of the water and then continues to be recycled; In the raw gas purification system of the methanol mixing pipeline, the circulating gas first passes through the absorption tower. After the activated carbon in the absorption tower adsorbs the sulfide in the circulating gas, the circulating gas is mixed and homogenized with the methanol from the methanol storage tank and then enters the second SCR device. The second SCR device is provided with a methanol catalyst. The circulating gas and methanol mixed gas are catalytically reduced to all nitrogen oxides under the action of the methanol catalyst and then enter the methanol synthesis device to synthesize methanol and generate purge gas. The purge gas enters the combustion end and the methanol enters the methanol storage tank. After the circulating gas has part of its water removed by the dehydration device, it enters the combustion and transportation pipeline and the clinker burning system (1), and is further divided into four routes in the combustion and transportation pipeline: the first route is lowered in temperature by the second heat exchanger and then goes to the air compressor device and then to the ash cleaning system; the second route goes to the conveying fan; the third route goes to the coal powder conveying system, and the fourth route goes to the sealing system; the transport to the clinker burning system (1) is divided into two routes, the first route is mixed with high-concentration oxygen from the air separation oxygen production device and then goes to the first cooling zone (171) of the grate cooler (17); the second route goes to the second cooling zone (172) of the grate cooler (17), thereby realizing the circulation of carbon dioxide.

10. A cement production line resource recovery method according to claim 9, characterized in that: When the pressure reamer (11) is working, the interior is filled with raw meal, and the raw meal is pushed into the system by the spiral blades. The raw meal enters the connecting pipeline from the second stage preheater to the first stage preheater, and exchanges heat with the circulating gas rich in high concentration of carbon dioxide in the pipeline, and enters the first stage preheater with the circulating gas; The raw meal in the circulating gas is collected by the first stage preheater and enters the connecting pipe between the third stage preheater and the second stage preheater, and enters the second stage preheater after heat exchange with the circulating gas; The raw meal is heat exchanged with the circulating gas in the second to fourth stage preheaters in sequence and then enters the decomposition furnace (15); The raw material is pre-decomposed in the decomposition furnace (15) and then enters the fifth-stage preheater. After being collected by the fifth-stage preheater, it enters the smoke chamber (19), and then enters the rotary kiln (16). After being burnt into clinker in the rotary kiln (16), the raw material enters the first cooling zone (171) of the grate cooler (17); The clinker is sequentially cooled to a required temperature in the first cooling zone (171), the second cooling zone (172), and the third cooling zone (173) of the grate cooler (17) and then enters the clinker storage (3) for storage; The carbon dioxide and nitrogen oxides generated during the sintering of the rotary kiln (16) into clinker and the carbon dioxide and nitrogen oxides generated during the decomposition of the decomposition furnace (15) follow the circulating gas and enter the first heat exchanger (4) to circulate in the circulating transport pipeline.

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