Gangue suspension decarbonization system

Abstract

The present invention discloses a coal gangue suspension decarbonization system, comprising an elevator, a preheating module, a suspension calcining furnace, a cooling module, a heat exchange module, a fresh air blower, a circulating fan, an exhaust pipe and a dust collector, wherein the elevator is used to lift raw materials, the preheating module is used to preheat raw materials, the suspension calcining furnace is used for suspension decarbonization, and the cooling module is used to cool finished products. After the flue gas is cooled by the heat exchanger, a part of it is discharged to the outside through the dust collector and the exhaust fan, and the other part enters the heat exchanger again after passing through the cooling module and the preheating module. The flue gas exchanges heat with the material in the preheating module and the cooling module in reverse, and reacts with the material in the calcining furnace in a forward direction. The coal gangue suspension decarbonization system provided by the present invention adopts a suspension process to complete the three processes of preheating, decarbonization and cooling of raw materials, effectively improving the heat transfer and mass transfer efficiency of the system, improving the decarbonization effect, and having high flue gas heat recovery efficiency. Most coal gangue with calorific value can achieve self-sustaining combustion.

Description

Technical Field

[0001] The invention relates to the technical field of calcination decarbonization, in particular to a gangue suspension decarbonization system. Background Art

[0002] Currently, the decarbonization of coal gangue is primarily achieved through calcination, and decarbonization still primarily involves lump and granular gangue. In traditional vertical kiln and sleeve rotary kiln processes, which primarily calcine lump and granular gangue, the primary heat exchange method is surface heat exchange on the accumulated gangue, resulting in very low heat transfer efficiency and generally requiring supplemental burning. Vertical kilns, which primarily calcine lump or pelletized gangue, face elimination due to their limited production capacity exceeding 300 tons per day and their environmental and energy efficiency requirements, failing to meet current industry requirements. Furthermore, small and medium-sized circulating fluidized furnace (CFB) power generation processes, which primarily utilize granular gangue, also fail to meet current industry requirements due to their high power consumption and small scale. Therefore, a new coal gangue decarbonization system is needed to improve heat transfer efficiency and reduce energy consumption. Summary of the Invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0004] To this end, an embodiment of the present invention provides a coal gangue suspension decarbonization system with high heat transfer efficiency and low energy consumption.

[0005] The coal gangue suspension decarbonization system of the embodiment of the present invention includes an elevator, which is used to lift raw materials; a preheating module, which has a flue gas inlet and a raw material input port, as well as a raw material outlet and a flue gas outlet, and the elevator transports raw materials to the preheating module through the raw material input port; a suspension calcining furnace, which is provided with a raw material inlet, a fuel inlet, a hot air inlet and a mixed outlet for outputting flue gas and materials, the raw material inlet is connected to the raw material outlet of the preheating module, and the fuel inlet is used to introduce fuel required for ignition or normal calcination; a cooling module, which is provided with a mixed inlet connected to the mixed outlet of the suspension calcining furnace, and the cooled finished product is discharged from the cooling module The material is discharged from the outlet of the cooling module and transported to the finished product warehouse; the heat exchange module and the fresh air fan, the fresh air fan is connected to the cold side air inlet of the heat exchange module, and the cold side outlet of the heat exchange module is connected to the hot air inlet of the suspension calciner; the flue gas circulation loop and the circulating fan, the flue gas circulation loop is connected in series with the preheating module, the cooling module, and the hot side of the heat exchange module to form a flue gas circulation, the circulating fan is connected in the flue gas circulation loop to provide a driving force for the flue gas circulation, the flue gas on the hot side of the heat exchange module is heat exchanged and cooled with the fresh air on the cold side, and then passed into the cooling module to cool the solid material first, and the high-temperature flue gas enters the preheating module through the flue gas inlet to preheat the raw material and then returns to the hot side of the heat exchange module.

[0006] The coal gangue suspension decarbonization system provided by the embodiment of the present invention includes a preheating module, a decarbonization module (suspension calciner) and a cooling module. The suspension process is adopted to complete the three processes of preheating, decarbonization and cooling of raw materials, effectively improving the heat transfer and mass transfer efficiency of the system, improving the decarbonization effect, recovering the heat of the flue gas, and improving the overall thermal efficiency of the system. It can also achieve self-sustaining combustion, greatly reducing the energy consumption of the system, and has outstanding innovations in environmental protection, energy saving and automation. There is no need to set up a rotary kiln, which greatly reduces the complexity of the system equipment, has lower requirements on the particle size and fluctuation of the raw materials, and is easier to control.

[0007] In some embodiments, the preheating module includes a multi-stage cyclone preheater connected in series, which is used for preheating raw meal. The top of each stage of the cyclone preheater is provided with a flue gas outlet, the bottom is provided with a raw meal outlet, and the side is provided with a mixing inlet for inputting flue gas and raw meal, and a feed inlet is provided on the pipeline connected to the mixing inlet of the cyclone preheater. A wind lock valve is provided at the raw meal outlet of the cyclone preheater, and the elevator feeds the first stage of the cyclone preheater through the feed inlet. The raw meal outlet of the cyclone preheater of the upper stage is connected to the feed inlet of the cyclone preheater of the lower stage, the flue gas outlet of the cyclone preheater of the lower stage is connected to the mixing inlet of the cyclone preheater of the upper stage, the raw meal outlet of the cyclone preheater of the last stage is connected to the raw meal inlet of the suspension calciner, the flue gas outlet of the cooling module is connected to the mixing inlet of the cyclone preheater of the last stage, and the flue gas outlet of the cyclone preheater of the first stage is connected to the hot side inlet of the heat exchange module.

[0008] In some embodiments, the cooling module includes multiple stages of cyclone coolers connected in series, and the multiple stages of cyclone coolers connected in series are used for cooling materials. The cyclone cooler at each stage is provided with a flue gas outlet at the top, a discharge port at the bottom, and a mixing inlet at the side, and a feed port is provided on the pipe connected to the mixing inlet of the cyclone cooler. A wind lock valve is provided at the raw material outlet of the cyclone cooler, the mixing outlet of the suspension calcining furnace is connected to the mixing inlet of the first stage cyclone cooler, the discharge port of the cyclone cooler of the previous stage is connected to the feed port of the cyclone cooler of the next stage, the flue gas outlet of the cyclone cooler of the next stage is connected to the mixing inlet of the cyclone cooler of the previous stage, the discharge port of the cyclone cooler of the last stage is connected to the finished product bin, the hot side outlet of the heat exchange module is connected to the mixing inlet of the cyclone cooler of the last stage, and the flue gas outlet of the cyclone cooler of the first stage is connected to the flue gas inlet of the preheating module.

[0009] In some embodiments, the heat exchange module includes multiple stages of heat exchangers connected in series, the flue gas outlet of the preheating module is connected to the hot side inlet of the first-stage heat exchanger, the hot side outlet of the last-stage heat exchanger is connected to the air inlet of the circulating fan, the fresh air fan outlet is connected to the cold side inlet of the last-stage heat exchanger, and the cold side outlet of the first-stage heat exchanger is connected to the hot air inlet.

[0010] In some embodiments, the gangue suspension decarbonization system includes an air cooler, the flue gas circulation loop connects the hot side outlet of the heat exchange module and the penultimate stage cyclone cooler, the air cooler outlet is connected to the mixing inlet of the last stage cyclone cooler for cooling solid materials, and the flue gas outlet of the last stage cyclone cooler is connected to the exhaust pipe and / or the fresh air fan inlet.

[0011] In some embodiments, the gangue suspension decarbonization system also includes a flue gas circulation branch, and the flue gas outlet of the cooling module is connected to the flue gas inlet of the preheating module through the flue gas circulation loop, and is also connected to the hot side of the heat exchange module through the flue gas circulation branch.

[0012] In some embodiments, the heat exchange module includes multiple stages of heat exchangers connected in series, the flue gas circulation branch connects the cooling module with the hot side inlet of the first-stage heat exchanger, the flue gas circulation loop connects the preheating module with the hot side inlet of the second-stage heat exchanger, the hot side outlet of the first-stage heat exchanger is connected with the hot side inlet of the second-stage heat exchanger, so that the hot side of the first-stage heat exchanger is connected in parallel with the flue gas circulation loop, the hot side outlet of the last-stage heat exchanger is connected with the air inlet of the circulating fan, the outlet of the fresh air fan is connected with the cold side inlet of the last-stage heat exchanger, the cold sides of the heat exchangers at each stage are connected in series, and the cold side outlet of the first-stage heat exchanger is connected with the hot air inlet of the suspension calcining furnace.

[0013] In some embodiments, the ratio of the flue gas circulation volume in the flue gas circulation loop to the fresh air volume of the fresh air fan is a flue gas circulation coefficient, and the flue gas circulation coefficient is 0.3 to 4.5.

[0014] In some embodiments, the suspension calciner is a hollow cylindrical structure, and its internal chamber is divided into a combustion zone, a reaction zone and a stabilization zone from bottom to top. The raw material inlet, the hot air inlet and the fuel inlet all correspond to the combustion zone; the suspension calciner is also provided with a flue gas inlet, and the circulating fan outlet is also connected to the flue gas inlet of the suspension calciner for conveying flue gas to the suspension calciner to control the oxygen concentration and temperature, so that the pressure of the suspension decarbonization system is 0.7atm~8.5atm.

[0015] In some embodiments, the gangue suspension decarbonization system further includes a waste heat boiler, which is connected in parallel with the heat exchange module so that high-temperature flue gas can selectively pass into the waste heat boiler to drive the operation of the waste heat boiler. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the coal gangue suspension decarbonization system in Example 1 of the present invention.

[0017] Figure 2 It is a structural diagram of the coal gangue suspension decarbonization system in the second embodiment of the present invention.

[0018] Figure 3 It is a structural diagram of the coal gangue suspension decarbonization system in the third embodiment of the present invention.

[0019] Figure 4 It is a structural diagram of the coal gangue suspension decarbonization system in the fourth embodiment of the present invention.

[0020] Figure 5 It is a structural diagram of the coal gangue suspension decarbonization system in the fifth embodiment of the present invention.

[0021] Reference numerals:

[0022] Gangue suspension decarbonization system 100;

[0023] Elevator 1, preheating module 2, first-stage cyclone preheater 211, second-stage cyclone preheater 212, third-stage cyclone preheater 213, mixing inlet 21, raw meal outlet 22, first flue gas outlet 23, first feed inlet 24;

[0024] Suspension calciner 3, raw material inlet 31, mixing outlet 32, hot air inlet 33, fuel inlet 34;

[0025] Cooling module 4, first-stage cyclone cooler 411, second-stage cyclone cooler 412, third-stage cyclone cooler 413, fourth-stage cyclone cooler 414, fifth-stage cyclone cooler 415, mixing inlet 41, discharge port 42, second flue gas outlet 43, second feed port 44;

[0026] Heat exchange module 5, first-stage heat exchanger 511, second-stage heat exchanger 512, third-stage heat exchanger 513;

[0027] Fresh air fan 61 , cooling air fan 62 , circulating air fan 63 , flue gas circulation loop 71 , flue gas circulation branch 72 , exhaust pipe 8 , dust collector 81 , waste heat boiler 9 . DETAILED DESCRIPTION

[0028] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0029] The following is based on Figure 1-Figure 5 The basic structure of the gangue suspension decarbonization system 100 provided by the embodiment of the present invention is described. The gangue suspension decarbonization system 100 includes an elevator 1, a preheating module 2, a suspension calcining furnace 3, a cooling module 4, a heat exchange module 5, a fresh air fan 61, a flue gas circulation loop 71 and a circulating fan 63.

[0030] The hoist 1 is used to lift the raw meal. The preheating module 2 is used to preheat the raw meal and has a flue gas inlet for inputting flue gas and a raw meal input port for inputting raw meal, as well as a raw meal outlet and a flue gas outlet. The hoist 1 transports the raw meal to the preheating module 2 through the raw meal input port.

[0031] The suspension calciner 3 is equipped with a raw meal inlet 31, a hot air inlet 33, a fuel inlet 34, and a mixed outlet 32 ​​for discharging flue gas and materials. The raw meal inlet 31 of the suspension calciner 3 is connected to the raw meal outlet of the preheating module 2. The preheated raw meal enters the suspension calciner 3 for calcination and decarburization. The resulting semi-finished product and high-temperature flue gas are discharged from the mixed outlet 32 ​​of the suspension calciner 3. The hot air inlet 33 is used to introduce combustion-supporting air, and the fuel inlet 34 is used to introduce fuel required for ignition and normal calcination.

[0032] The cooling module 4 is provided with a mixing inlet connected to the mixing outlet 32 ​​of the suspension calciner 3. The cooling module 4 is used to cool and separate the semi-finished products and high-temperature flue gas produced by the calcination. The cooled and separated finished products (solids) are discharged from the discharge port of the cooling module 4 and transported to the finished product bin.

[0033] The heat exchange module 5 is used to cool the flue gas and heat the fresh air. Fresh air circulates on its cold side, while flue gas circulates on its hot side. A fresh air blower 61 is connected to the cold side inlet of the heat exchange module 5 to blow fresh air into the cold side of the heat exchange module 5. The cold side outlet of the heat exchange module 5 is connected to the hot air inlet 33 of the suspension calciner 3 to deliver air to the suspension calciner 3 for combustion support.

[0034] The flue gas circulation loop 71 connects the preheating module 2, cooling module 4, and the hot side of the heat exchange module 5 in series, forming a loop. The flue gas circulates within the flue gas circulation loop 71, releasing and absorbing heat in sequence. A circulating fan 63 is connected to the flue gas circulation loop 71 to provide the driving force for the flue gas circulation. After the flue gas from the hot side of the heat exchange module 5 exchanges heat with the fresh air from the cold side and cools down, it is passed into the cooling module 4 to initially cool the solid material. The high-temperature flue gas then enters the preheating module 2 through the flue gas inlet, preheats the raw material, and then returns to the hot side of the heat exchange module 5.

[0035] The coal gangue suspension decarbonization system provided by the embodiment of the present invention includes a preheating module, a decarbonization module (suspension calciner) and a cooling module. The suspension process is adopted to complete the three processes of preheating, decarbonization and cooling of raw materials, effectively improving the heat transfer and mass transfer efficiency of the system, improving the decarbonization effect, recovering the heat of the flue gas, and improving the overall thermal efficiency of the system. It can achieve self-sustaining combustion for coal gangue with 600kcal / kg, greatly reducing the energy consumption of the system, and has outstanding innovations in environmental protection, energy saving and automation. There is no need to set up a rotary kiln, which greatly reduces the complexity of the system equipment, has lower requirements on the particle size and fluctuation of the raw materials, and is easier to control.

[0036] In some embodiments, the gangue suspension decarbonization system includes an exhaust pipe 8 and a dust collector 81. The hot-side outlet of the heat exchange module 5 is also connected to the exhaust pipe 8, meaning that the flue gas discharged from the hot-side outlet of the heat exchange module 5 can be passed into the cooling module 4 or discharged through the exhaust pipe 8. The dust collector 81 is installed on the exhaust pipe 8 to remove dust, which is then discharged through a chimney after environmental treatment. Optionally, the solid material separated by the dust collector 81 can be sent to the finished product bin.

[0037] After the flue gas is cooled by the heat exchange module 5, part of it is discharged to the outside through the exhaust pipe 8, and the other part passes through the cooling module 4 and the preheating module 2 and then enters the heat exchange module 5 again. The flue gas exchanges heat with the material in the preheating module 2 and the cooling module 4 in the reverse direction, and reacts with the material in the calcining furnace in the forward direction.

[0038] In some embodiments, the gangue suspension decarbonization system includes a homogenization silo equipped with equipment for mechanical or pneumatic homogenization, and an elevator 1 that lifts the raw meal from the homogenization silo into the preheating module 2. Preferably, the raw meal output from the homogenization silo has a particle size of less than or equal to 0.05 mm.

[0039] In some embodiments, the preheating module 2 includes multiple stages of cyclone preheaters connected in series, which are used to preheat the raw meal. The raw meal flows from the first stage cyclone preheater to the last stage cyclone preheater in sequence.

[0040] In some specific embodiments, Figure 1-Figure 5 As shown, each stage of the cyclone preheater is provided with a first flue gas outlet 23 at the top, a raw meal outlet 22 at the bottom, and a mixing inlet 21 at the side. A first feed inlet 24 is provided on the pipe connected to the mixing inlet 21 of the cyclone preheater. An air lock valve is provided at the raw meal outlet 22 of the cyclone preheater. The raw meal outlet 22 of the previous stage cyclone preheater is connected to the first feed inlet 24 of the next stage cyclone preheater. The raw meal circulates sequentially along the multiple stages of cyclone preheaters connected in series and is heated during the circulation process. The raw meal outlet 22 of the last stage cyclone preheater is connected to the raw meal inlet 31 of the suspension calciner 3. The preheated raw meal is fed into the suspension calciner 3, which helps to improve the calcination efficiency.

[0041] It should be noted that the mixing inlet 21 of the cyclone preheater is used to input flue gas and raw meal. The raw meal input port of the preheating module 2 described above is actually the first feed port 24 provided on the pipeline connected to the mixing inlet 21 of the first-stage cyclone preheater. The elevator 1 inputs raw meal through the first feed port 24. The raw meal enters the mixing inlet 21 of the first cyclone preheater along the pipeline, comes into contact with the flue gas in the first-stage cyclone preheater for preheating, and is sequentially transported to the next-stage cyclone preheater, and finally discharged from the raw meal outlet 22 of the final-stage cyclone preheater. The raw meal outlet of the preheating module 2 described above is actually the raw meal outlet 22 of the final-stage cyclone preheater.

[0042] In some embodiments of the present invention, the heat in the flue gas generated by calcination is recovered and utilized to preheat the raw meal, and the flue gas circulates in a countercurrent manner with the raw meal in a multi-stage cyclone preheater. Specifically, the flue gas outlet of the cooling module 4 is connected to the mixing inlet 21 of the last-stage cyclone preheater. The flue gas inlet of the preheating module 2 described above is actually the mixing inlet 21 of the last-stage cyclone preheater. The first flue gas outlet 23 of the next-stage cyclone preheater is connected to the mixing inlet 21 of the previous-stage cyclone preheater. The first flue gas outlet 23 of the first-stage cyclone preheater is connected to the hot-side inlet of the heat exchange module 5. The flue gas outlet of the preheating module 2 described above is actually the first flue gas outlet 23 of the first-stage cyclone preheater. The high-temperature flue gas flowing out of the cooling module 4 is passed into the last-stage cyclone preheater. The flue gas and the raw meal circulate in a countercurrent manner to preheat the raw meal, and finally flow out of the first-stage cyclone preheater and enter the hot side of the heat exchange module 5.

[0043] In some embodiments, the cooling module 4 includes multiple stages of cyclone coolers connected in series. The multiple stages of cyclone coolers connected in series are used to cool the material. The cyclone coolers are also used to separate the flue gas and solid material in the calcined mixture. The flue gas circulates in the reverse direction of the material in the series cyclone coolers. After the mixture undergoes multi-stage separation, the solid material is discharged from the discharge port 42 of the last stage cyclone cooler and transported to the finished product bin. The cyclone coolers are the first to Nth stage cyclone coolers from upstream to downstream. "Upstream" and "downstream" here refer to the flow direction of the material.

[0044] In some specific embodiments, Figure 1-Figure 5As shown, each stage of the cyclone cooler is provided with a second flue gas outlet 43 at the top, a discharge port 42 at the bottom, a mixing inlet 41 at the side, and a second feed port 44 on the pipe connected to the mixing inlet 41 of the cyclone cooler. An air lock valve is provided at the discharge port 42 of the cyclone cooler. The mixing outlet 32 ​​of the suspension calciner 3 is connected to the mixing inlet 41 of the first stage cyclone cooler. The flue gas and semi-finished product materials generated by the calcination of the suspension calciner 3 enter the inlet pipe of the first cyclone cooler through the second feed port 44 and enter the first cyclone cooler. The discharge port 42 of the upper stage cyclone cooler is connected to the second feed port 44 of the lower stage cyclone cooler, and the material flows from there to the lower stage cyclone cooling air. The discharge port 42 of the last stage cyclone cooler is connected to the finished product bin. In this process, the material is cooled.

[0045] In some embodiments of the present invention, the flue gas on the hot side of the heat exchange module 5 exchanges heat with the fresh air on the cold side and then flows into the series-connected cyclone coolers to absorb heat and cool the solid material. Specifically, the hot side outlet of the heat exchange module 5 is connected to the mixing inlet 41 of the last-stage cyclone cooler, and the second flue gas outlet 43 of the next-stage cyclone cooler is connected to the mixing inlet 41 of the previous-stage cyclone cooler. The flue gas then flows to the upstream cyclone cooler and merges. The second flue gas outlet 43 of the first-stage cyclone cooler is connected to the flue gas inlet of the preheating module 2. That is, the high-temperature flue gas after absorbing heat enters the preheating module 2 to preheat the raw material, and then returns to the hot side of the heat exchange module 5 to exchange heat with the fresh air. The fresh air absorbs the temperature of the high-temperature flue gas on the hot side and then heats up, and then enters the suspension calciner 3 through the hot air inlet 33.

[0046] In the embodiment of the present invention, the down-flow calcination, counter-flow cooling and flue gas circulation technology effectively improve the heat transfer and mass transfer efficiency of the system.

[0047] In some embodiments, as Figure 1-Figure 5 As shown, the heat exchange module 5 includes multiple stages of heat exchangers connected in series. The flue gas outlet of the preheating module 2 (i.e., the flue gas outlet of the first-stage cyclone preheater) is connected to the hot-side inlet of the first-stage heat exchanger. The hot-side outlet of the final-stage heat exchanger is connected to the air inlet of the circulating fan 63. The outlet of the fresh air fan 61 is connected to the cold-side inlet of the final-stage heat exchanger. The cold-side outlet of the first-stage heat exchanger is connected to the hot air inlet 33 of the suspension calciner 3.

[0048] Here, a heat exchanger refers to a heat exchanger whose cold side and hot side are both connected in series, and in the embodiment of the present invention, the flow direction of the heat exchange medium in the cold side and the hot side is opposite. Specifically, in two adjacent heat exchangers, the hot side outlet of the upper heat exchanger is connected to the hot side inlet of the lower heat exchanger, and the cold side outlet of the lower heat exchanger is connected to the cold side inlet of the upper heat exchanger. The flue gas exhausted from the preheating module 2 enters the hot side of the first-stage heat exchanger and flows to the hot side of the last-stage heat exchanger in sequence, and enters the cooling module 4 after cooling. The fresh air on the cold side, on the contrary, flows from the cold side of the last-stage heat exchanger in sequence to the cold side of the first-stage heat exchanger, and enters the suspension calcining furnace 3 after heating.

[0049] In some embodiments, the gangue suspension decarbonization system 100 further includes an air cooler 62. A flue gas circulation loop 71 connects the hot-side outlet of the heat exchange module 5 to the penultimate cyclone cooler. In other words, the flue gas flowing out of the hot-side outlet of the heat exchange module 5 directly enters the penultimate cyclone cooler and circulates upward in sequence. The final cyclone cooler is cooled by ambient air. The outlet of the air cooler 62 connects to the final cyclone cooler for cooling the solid material. The exhaust port of the final cyclone cooler is connected to the exhaust pipe 8 and / or the inlet of the fresh air blower 61.

[0050] For example, the exhaust port of the last-stage cyclone cooler is connected to the exhaust pipe 8 , and the air after cooling the solid material is discharged through the exhaust pipe 8 .

[0051] Alternatively, the exhaust port of the last-stage cyclone cooler is connected to the inlet of the fresh air fan 61 , and the air after cooling the solid material enters the fresh air fan 61 to provide air for the fresh air fan 61 .

[0052] Alternatively, the exhaust port of the last stage cyclone cooler is connected to each of the exhaust pipe 8 and the fresh air blower 61 , and part of the air after cooling the solid material enters the fresh air blower 61 to provide air for the fresh air blower 61 , and the other part is discharged through the exhaust pipe 8 .

[0053] Optionally, a portion of the flue gas exhausted by the cooling module 4 is passed into the preheating module 2, and the other portion directly enters the heat exchange module 5. In some embodiments, the coal gangue suspension decarbonization system 100 further includes a flue gas circulation branch 72, and the second flue gas outlet 43 of the cooling module 4 is connected to the preheating module 2 through the flue gas circulation loop 71, and is also connected to the hot side of the heat exchange module 5 through the flue gas circulation branch 72.

[0054] In some preferred embodiments, the cyclone cooler is a cyclone separator, and the cyclone separator includes at least four stages.

[0055] In some embodiments, the gangue suspension decarbonization system 100 further includes a waste heat boiler 9 , which is connected in parallel with the heat exchange module 5 so that high-temperature flue gas can selectively flow into the waste heat boiler 9 to drive the waste heat boiler 9 to operate.

[0056] The following is based on Figure 1-5 The coal gangue suspension decarbonization system 100 in several specific embodiments of the present invention is described.

[0057] Example 1:

[0058] like Figure 1 As shown, the gangue suspension decarbonization system 100 includes an elevator 1, a preheating module 2, a suspension calcining furnace 3, a cooling module 4, a heat exchange module 5, a fresh air fan 61, a flue gas circulation loop 71 and a circulating fan 63, an exhaust pipe 8 and a dust collector 81.

[0059] like Figure 1 As shown, the preheating module 2 includes three cyclone preheaters connected in series: a first-stage cyclone preheater 211, a second-stage cyclone preheater 212, and a third-stage cyclone preheater 213. The elevator 1 is connected to a first feed inlet 24 on a pipeline connected to the mixing inlet 21 of the first-stage cyclone preheater 211. The raw meal outlet 22 of the first-stage cyclone preheater 211 is connected to the mixing inlet 21 of the second-stage cyclone preheater 212 via a pipeline. The raw meal outlet 22 of the second-stage cyclone preheater 212 is connected to the mixing inlet 21 of the third-stage cyclone preheater 213 via a pipeline. The raw meal outlet 22 of the third-stage cyclone preheater 213 is connected to the raw meal inlet 31 of the suspension calciner 3.

[0060] The suspension calciner 3 is a hollow cylindrical structure, its internal chamber divided from bottom to top into a combustion zone, a reaction zone, and a stabilization zone. The raw material inlet 31, hot air inlet 33, and fuel inlet 34 of the suspension calciner 3 all correspond to the combustion zone, and the mixing outlet 32 ​​of the suspension calciner 3 is located at the top of the furnace. For gangue decarbonization, diesel fuel is used, and normal operation is primarily based on self-sustaining combustion of the gangue (calorific value of no less than 400 kcal / kg).

[0061] The cooling module 4 includes five stages of cyclone coolers connected in series: a first-stage cyclone cooler 411, a second-stage cyclone cooler 412, a third-stage cyclone cooler 413, a fourth-stage cyclone cooler 414, and a fifth-stage cyclone cooler 415. The cyclone coolers are cyclone separators. The mixing outlet 32 ​​of the suspension calciner 3 is connected to a second feed port 44 on a pipeline connected to the mixing inlet 41 of the first-stage cyclone cooler 411. The discharge port 42 of the first-stage cyclone cooler 411 is connected to the mixing inlet 41 of the second-stage cyclone cooler 412 via a pipeline. Similarly, the discharge port 42 of the fifth-stage cyclone cooler 415 is connected to the finished product bin, transporting the decarbonized material to the finished product bin.

[0062] The heat exchange module 5 includes two stages of heat exchangers connected in series: a first-stage heat exchanger 511 and a second-stage heat exchanger 512. The outlet of the fresh air blower 61 is connected to the cold-side inlet of the second-stage heat exchanger 512, which in turn is connected to the cold-side inlet of the first-stage heat exchanger 511. The cold-side outlet of the first-stage heat exchanger 511 is connected to the hot air inlet 33 of the suspension calciner 3.

[0063] The flue gas circulation loop 71 connects the preheating module 2, cooling module 4, and heat exchange module 5 in series. Specifically, the hot side outlet of the second-stage heat exchanger 512 is connected to the mixing inlet 41 of the fifth-stage cyclone cooler 415 via a pipe, and a circulating fan 63 for circulating the flue gas is provided on the flue gas pipe. The second flue gas outlet 43 of the fifth-stage cyclone cooler 415 is connected to the mixing inlet 41 of the fourth-stage cyclone cooler 414 via a pipe. The second flue gas outlet 43 of the fourth-stage cyclone cooler 414 is connected to the mixing inlet 41 of the third-stage cyclone cooler 413 via a pipe. Similarly, the second flue gas outlet 43 of the first-stage cyclone cooler 411 is connected to the mixing inlet 21 of the third-stage cyclone preheater 213 via a pipe. The first flue gas outlet 23 of the third-stage cyclone preheater 213 is connected to the mixing inlet 21 of the second-stage cyclone preheater 212. The first flue gas outlet 23 of the second-stage cyclone preheater 212 is connected to the mixing inlet 21 of the first-stage cyclone preheater 211. The first flue gas outlet 23 of the first-stage cyclone preheater 211 is connected to the hot-side inlet of the first-stage heat exchanger 511. The hot-side outlet of the first-stage heat exchanger 511 is connected to the hot-side inlet of the second-stage heat exchanger 512, forming a flue gas circulation loop.

[0064] The suspension decarbonization process of the gangue suspension decarbonization system 100 provided in this embodiment is as follows:

[0065] The hoist 1 delivers the homogenized raw meal in the homogenization bin into the first-stage cyclone preheater 211. The raw meal flows downward from the first-stage cyclone preheater 211 to complete preheating, and is input into the suspension calciner 3 from the third-stage cyclone preheater 213 for calcination. The semi-finished product and flue gas produced by the calcination are discharged from the mixing outlet 32 ​​at the top of the suspension calciner 3 and enter the first-stage cyclone cooler 411. Solid-gas separation is performed in the first-stage cyclone cooler 411, and the solid material enters the second-stage cyclone cooler 412 from the discharge port 42. The second-stage cyclone cooler 412 continues to perform solid-gas separation. The solid material flows downward in sequence, and the flue gas flows upward in sequence after separation. The discharge port 42 at the bottom of the fifth-stage cyclone cooler 415 is connected to the finished product bin.

[0066] The second flue gas outlet 43 of the first-stage cyclone cooler 411 is connected to the mixing inlet 21 of the third-stage cyclone preheater 213. The flue gas flows upward in sequence to preheat the raw meal, flows out of the first-stage cyclone preheater 211, enters the hot side inlet of the first-stage heat exchanger 511, and enters the second-stage heat exchanger 512 after heat exchange. The flue gas flows out of the hot side of the second-stage heat exchanger 512 and enters the fifth-stage cyclone cooler 415, flows upward in sequence, and flows out from the second flue gas outlet 43 of the first-stage cyclone cooler 411 to perform flue gas circulation.

[0067] The flue gas releases heat in the cyclone preheater, absorbs heat in the cyclone cooler, and releases heat in the heat exchanger.

[0068] The counter-current cooling technology in the cooling module 4 can cool the decarbonized fly ash product to less than 100 degrees Celsius within 1 minute.

[0069] In this embodiment, co-current calcination is carried out in the suspension calcining furnace 3. The co-current calcination technology can complete the decarbonization of the coal gangue within 15 seconds, and the activity remains intact. At the same time, decarbonization is completed without the pores of the particles being closed. The decarbonization effect is far superior to other current decarbonization methods, and the loss on ignition can be reduced to less than 3%.

[0070] Furthermore, the suspension calciner 3 may be equipped with a flue gas inlet (not shown). The outlet of the circulating fan 63 is also connected to the flue gas inlet of the suspension calciner 3, thereby supplying flue gas to the suspension calciner 3 to control the oxygen concentration and temperature, thereby stabilizing the pressure of the suspension decarburization system within the range of 0.7 atm-8.5 atm. Utilizing flue gas circulation technology, the oxygen, pressure, temperature, and concentration within the suspension calciner 3 are precisely controlled and operate stably, ensuring a reducing atmosphere during the calcination and cooling processes, preventing the iron oxide from turning red and effectively controlling the product color.

[0071] The ratio of the flue gas circulation volume in the flue gas circulation loop 71 to the fresh air volume of the fresh air blower 61 is the flue gas circulation coefficient. Preferably, the flue gas circulation coefficient of the coal gangue suspension decarbonization system 100 is 0.3 to 4.5.

[0072] Furthermore, the high-temperature gas can also power a waste heat boiler, producing high-pressure steam as a byproduct for electricity generation, enabling both self-use and external power export. During normal operation using the gangue suspension decarbonization system 100 provided by the present invention, when the gangue's dry basis calorific value exceeds 400 kcal / kg, it can achieve self-sustaining combustion and power a waste heat boiler.

[0073] Example 2:

[0074] The gangue suspension decarbonization system 100 provided in this embodiment includes an elevator 1, a preheating module 2, a suspension calcining furnace 3, a cooling module 4, a heat exchange module 5, a fresh air fan 61, a cold air fan 62, a flue gas circulation loop 71 and a circulating fan 63, an exhaust pipe 8 and a dust collector 81.

[0075] like Figure 2 As shown, the arrangement of the elevator 1, preheating module 2, suspension calciner 3, cooling module 4, heat exchange module 5, fresh air blower 61, exhaust pipe 8, and dust collector 81 can refer to the first embodiment. Only the differences between this embodiment and the first embodiment are described below.

[0076] like Figure 2 As shown, the pipeline in the flue gas circulation loop 71 directly connects the hot side outlet of the second-stage heat exchanger 512 and the fourth-stage cyclone cooler 414. The circulation fan 63 is connected to the pipeline between the hot side outlet of the second-stage heat exchanger 512 and the fourth-stage cyclone cooler 414. The flue gas pipelines in the first-stage cyclone cooler 411, the second-stage cyclone cooler 412, the third-stage cyclone cooler 413, and the fourth-stage cyclone cooler 414 are connected in series.

[0077] The fifth-stage cyclone cooler 415 is cooled using room-temperature air. The outlet of the air cooler 62 is connected to the mixing inlet 41 of the fifth-stage cyclone cooler 415, and the exhaust port of the fifth-stage cyclone cooler 415 is connected to the exhaust pipe 8. The air cooler 62 introduces room-temperature air into the fifth-stage cyclone cooler 415. After the air cools the solid material, it is discharged through the exhaust pipe 8.

[0078] Example 3:

[0079] The gangue suspension decarbonization system 100 provided in this embodiment includes an elevator 1, a preheating module 2, a suspension calcining furnace 3, a cooling module 4, a heat exchange module 5, a fresh air fan 61, a cold air fan 62, a circulating fan 63, a flue gas circulation loop 71, a flue gas circulation branch 72, an exhaust pipe 8, and a dust collector 81.

[0080] like Figure 3 As shown, the arrangement of the elevator 1, preheating module 2, suspension calcining furnace 3, cooling module 4, fresh air blower 61, cooling air blower 62, flue gas circulation loop 71, exhaust pipe 8, and dust collector 81 can refer to the second embodiment. Only the differences between this embodiment and the second embodiment are described below.

[0081] In this embodiment, the heat exchange module 5 includes three stages of heat exchangers connected in series: a first-stage heat exchanger 511, a second-stage heat exchanger 512, and a third-stage heat exchanger 513. The hot side outlet of the first-stage heat exchanger 511 is connected to the hot side inlet of the second-stage heat exchanger 512, the hot side outlet of the second-stage heat exchanger 512 is connected to the hot side inlet of the third-stage heat exchanger 513, and the hot side outlet of the third-stage heat exchanger 513 is connected to the fourth-stage cyclone cooler 414.

[0082] like Figure 3 As shown, the flue gas circulation loop 71 connects the preheating module 2 with the hot-side inlet of the second-stage heat exchanger 512. The inlet end of the flue gas circulation branch 72 connects to the second flue gas outlet 43 of the first-stage cyclone cooler 411, and the outlet end connects to the hot-side inlet of the first-stage heat exchanger 511. The flue gas at the hot-side outlet of the first-stage heat exchanger 511 merges with the flue gas from the flue gas circulation loop 71 and enters the hot-side of the second-stage heat exchanger 512. A portion of the flue gas exhausted from the first-stage cyclone cooler 411 enters the preheating module 2 through the flue gas circulation loop 71 to preheat the raw meal, while the remaining portion enters the heat exchange module 5 through the flue gas circulation branch 72 to exchange heat with the cold side.

[0083] Example 4:

[0084] The gangue suspension decarbonization system 100 provided in this embodiment includes an elevator 1, a preheating module 2, a suspension calcining furnace 3, a cooling module 4, a heat exchange module 5, a fresh air fan 61, a cold air fan 62, a flue gas circulation loop 71, a flue gas circulation branch 72, an exhaust pipe 8, and a dust collector 81.

[0085] like Figure 4 As shown, the arrangement of the elevator 1, preheating module 2, suspension calcining furnace 3, cooling module 4, heat exchange module 5, fresh air blower 61, cooling air blower 62, flue gas circulation loop 71, flue gas circulation branch 72, exhaust pipe 8, and dust collector 81 can refer to the third embodiment. Only the differences between this embodiment and the third embodiment are described below.

[0086] The exhaust port of the fifth-stage cyclone cooler 415 is connected to each of the exhaust pipe 8 and the fresh air blower 61 . Part of the air after cooling the solid material enters the fresh air blower 61 to provide air for the fresh air blower 61 , and the other part is discharged through the exhaust pipe 8 .

[0087] Embodiment 5:

[0088] The gangue suspension decarbonization system 100 provided in this embodiment includes an elevator 1, a preheating module 2, a suspension calcining furnace 3, a cooling module 4, a heat exchange module 5, a fresh air fan 61, a cold air fan 62, a flue gas circulation loop 71, a flue gas circulation branch 72, an exhaust pipe 8, a dust collector 81, and a waste heat boiler 9.

[0089] like Figure 5 As shown, the arrangement of the elevator 1, preheating module 2, suspension calcining furnace 3, cooling module 4, heat exchange module 5, fresh air blower 61, cooling air blower 62, flue gas circulation loop 71, flue gas circulation branch 72, exhaust pipe 8, and dust collector 81 can refer to the fourth embodiment. Only the differences between this embodiment and the fourth embodiment are described below.

[0090] like Figure 5As shown, waste heat boiler 9 is connected in parallel with heat exchange module 5 to selectively pass high-temperature flue gas into waste heat boiler 9, driving its operation. The waste heat boiler 9 generates high-pressure steam as a by-product, which can be used for both internal and external power supply. During normal operation using the gangue suspension decarbonization system 100 provided by the embodiment of the present invention, when the dry basis calorific value of the gangue exceeds 400 kcal / kg, it can achieve self-sustaining combustion and drive waste heat boiler 9 to generate electricity, further improving energy utilization.

[0091] Specifically, in this embodiment, the waste heat boiler 9 is connected in parallel with the second heat exchanger 512 and the third heat exchanger 513 in the heat exchange module 5. The high-temperature flue gas in the flue gas circulation loop 71 can enter the flue gas inlet of the waste heat boiler 9, and the flue gas outlet of the waste heat boiler 9 is connected to the inlet of the circulation fan 63. In this embodiment, the hot side outlet of the third heat exchanger 513 is connected to the exhaust pipe 8.

[0092] Furthermore, the hot-side outlet of the first heat exchanger 511 is connected to the flue gas inlet of the waste heat boiler 9. In other words, the high-temperature flue gas in the flue gas circulation loop 71 can be input into the waste heat boiler 9, and the high-temperature flue gas at the hot-side outlet of the first heat exchanger 511 can also be input into the waste heat boiler 9, driving the operation of the waste heat boiler 9.

[0093] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0094] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0095] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0096] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0097] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0098] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A coal gangue suspension decarbonization system, characterized in that: include: An elevator, the elevator being used to elevate raw materials; A preheating module, wherein the preheating module has a smoke inlet and a raw material input port, as well as a raw material outlet and a smoke outlet, and the hoist transports the raw material to the preheating module through the raw material input port; A suspension calciner is provided with a raw meal inlet, a fuel inlet, a hot air inlet, and a mixed outlet for outputting flue gas and materials. The raw meal inlet is connected to the raw meal outlet of the preheating module, and the fuel inlet is used to introduce fuel required for ignition or normal calcination; A cooling module, wherein the cooling module is provided with a mixing inlet connected to the mixing outlet of the suspension calcining furnace, and the cooled finished product is discharged from the discharge port of the cooling module and transported to the finished product bin; A heat exchange module and a fresh air fan, wherein the fresh air fan is connected to the cold side air inlet of the heat exchange module, and the cold side outlet of the heat exchange module is connected to the hot air inlet of the suspension calcining furnace; A flue gas circulation loop and a circulation fan, wherein the flue gas circulation loop is connected in series with the preheating module, the cooling module and the hot side of the heat exchange module to form a flue gas circulation. The circulation fan is connected in the flue gas circulation loop to provide a driving force for the flue gas circulation. After the flue gas on the hot side of the heat exchange module is heat-exchanged and cooled with the fresh air on the cold side, it is passed into the cooling module to first cool the solid material. The high-temperature flue gas enters the preheating module through the flue gas inlet to preheat the raw material and then returns to the hot side of the heat exchange module.

2. The gangue suspension decarbonization system according to claim 1, characterized in that: The preheating module includes a multi-stage cyclone preheater connected in series, which is used for preheating raw meal. The top of each stage of the cyclone preheater is provided with a flue gas outlet, the bottom is provided with a raw meal outlet, and the side is provided with a mixed inlet for inputting flue gas and raw meal, and a feed inlet is provided on the pipeline connected to the mixed inlet of the cyclone preheater. A wind lock valve is provided at the raw meal outlet of the cyclone preheater. The elevator feeds the first-stage cyclone preheater through the feed inlet, the raw meal outlet of the upper-stage cyclone preheater is connected to the feed inlet of the lower-stage cyclone preheater, the flue gas outlet of the lower-stage cyclone preheater is connected to the mixed inlet of the upper-stage cyclone preheater, the raw meal outlet of the last-stage cyclone preheater is connected to the raw meal inlet of the suspension calciner, the flue gas outlet of the cooling module is connected to the mixed inlet of the last-stage cyclone preheater, and the flue gas outlet of the first-stage cyclone preheater is connected to the hot side inlet of the heat exchange module.

3. The gangue suspension decarbonization system according to claim 1, characterized in that: The cooling module includes multiple stages of cyclone coolers connected in series, which are used in series to cool materials. The cyclone coolers at each stage are provided with a flue gas outlet at the top, a discharge port at the bottom, and a mixing inlet at the side, and a feed port is provided on the pipeline connected to the mixing inlet of the cyclone cooler. A wind lock valve is provided at the discharge port of the cyclone cooler, the mixing outlet of the suspension calcining furnace is connected to the mixing inlet of the first stage cyclone cooler, the discharge port of the cyclone cooler at the upper stage is connected to the feed port of the cyclone cooler at the lower stage, the flue gas outlet of the cyclone cooler at the lower stage is connected to the mixing inlet of the cyclone cooler at the upper stage, the discharge port of the cyclone cooler at the last stage is connected to the finished product bin, the hot side outlet of the heat exchange module is connected to the mixing inlet of the cyclone cooler at the last stage, and the flue gas outlet of the cyclone cooler at the first stage is connected to the flue gas inlet of the preheating module.

4. The coal gangue suspension decarbonization system according to any one of claims 1 to 3, characterized in that: The heat exchange module includes multiple stages of heat exchangers connected in series, the flue gas outlet of the preheating module is connected to the hot side inlet of the first-stage heat exchanger, the hot side outlet of the last-stage heat exchanger is connected to the air inlet of the circulation fan, the fresh air fan outlet is connected to the cold side inlet of the last-stage heat exchanger, and the cold side outlet of the first-stage heat exchanger is connected to the hot air inlet.

5. The gangue suspension decarbonization system according to claim 3, characterized in that: It includes an air cooler, the flue gas circulation loop connects the hot side outlet of the heat exchange module and the penultimate stage cyclone cooler, the air cooler outlet is connected to the mixing inlet of the last stage cyclone cooler for cooling solid materials, and the flue gas outlet of the last stage cyclone cooler is connected to the exhaust pipe and / or the fresh air fan inlet.

6. The gangue suspension decarbonization system according to claim 1 or 5, characterized in that: It also includes a flue gas circulation branch, and the flue gas outlet of the cooling module is connected to the flue gas inlet of the preheating module through the flue gas circulation loop, and is also connected to the hot side of the heat exchange module through the flue gas circulation branch.

7. The gangue suspension decarbonization system according to claim 6, characterized in that: The heat exchange module includes multiple stages of heat exchangers connected in series. The flue gas circulation branch connects the cooling module with the hot side inlet of the first-stage heat exchanger, the flue gas circulation loop connects the preheating module with the hot side inlet of the second-stage heat exchanger, the hot side outlet of the first-stage heat exchanger is connected with the hot side inlet of the second-stage heat exchanger, so that the hot side of the first-stage heat exchanger is connected in parallel with the flue gas circulation loop, the hot side outlet of the last-stage heat exchanger is connected with the air inlet of the circulating fan, the outlet of the fresh air fan is connected with the cold side inlet of the last-stage heat exchanger, the cold sides of the heat exchangers at each stage are connected in series, and the cold side outlet of the first-stage heat exchanger is connected with the hot air inlet of the suspension calcining furnace.

8. The gangue suspension decarbonization system according to claim 1, characterized in that: The ratio of the flue gas circulation volume in the flue gas circulation loop to the fresh air volume of the fresh air fan is a flue gas circulation coefficient, and the flue gas circulation coefficient is 0.3 to 4.

5.

9. The gangue suspension decarbonization system according to claim 1, characterized in that: The suspension calcining furnace is a hollow cylindrical structure, and its internal chamber is divided into a combustion zone, a reaction zone and a stabilization zone from bottom to top. The raw material inlet, the hot air inlet and the fuel inlet all correspond to the combustion zone; The suspension calciner is also provided with a flue gas inlet, and the circulating fan outlet is also connected to the flue gas inlet of the suspension calciner for conveying flue gas to the suspension calciner to control the oxygen concentration and temperature so that the pressure of the suspension decarbonization system is 0.7atm~8.5atm.

10. The gangue suspension decarbonization system according to claim 1, characterized in that: It also includes a waste heat boiler, which is connected in parallel with the heat exchange module so that high-temperature flue gas can selectively flow into the waste heat boiler to drive the waste heat boiler to operate.

Images