Low-carbon sintering system

Abstract

The utility model belongs to the technical field of low-carbon sintering, and discloses a low-carbon sintering system aiming at the problem of large sintering carbon emission caused by large fossil energy consumption in the existing sintering process, and according to the sintering system, a sintering machine is sequentially divided into a drying section, a preheating section and a roasting section according to the running direction of the sintering machine. And the ignition burner is arranged in the ignition furnace above the downstream side of the preheating section. And the material outlet of the batching device is communicated with the material inlet of the distributing device. A material outlet of the material distributing device is formed in the feeding end of the sintering machine. And the blowing device is arranged above the roasting section. And the discharging end of the sintering machine is communicated with the feeding end of the circular cooler. The system is simple in structure, biomass can be respectively utilized according to different particle sizes after being crushed, meanwhile, combustion-supporting gas and fuel are rapidly and evenly mixed through the structure of the ignition burner, efficient combustion is achieved, the gasification intensity and the yield of H2 in gasified gas are increased through the gasification device, and high practicability is achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to a sintering system, concretely relates to a low carbon sintering system based on biomass separate quality treatment belongs to sintering technical field. BACKGROUND

[0002] General sintering procedure is one of the main methods of iron ore lumping in steel flow. The current sintering mainstream process is to adopt the downdraught sintering, and the main equipment has the belt sintering machine, the ignition heat preservation furnace, the distributor, the ring cooling machine etc. The belt sintering machine has become the absolute mainstream of the world sintering production due to the high single machine output and the high mechanization and automation degree.

[0003] The domestic and foreign researchers have carried out a lot of low carbon research and attempt to sintering procedure, such as adopting the biomass sintering, the gas injection etc. Due to the innate defect of biomass fuel, the biomass sintering currently only stays in the laboratory research, and still cannot be popularized in industry on a large scale;The gas injection is a kind of method for reducing coke use by injecting gas to the sintering material surface in recent years, but the gas for injection still mainly is the coke oven gas and natural gas, and it still comes from fossil energy in essence, and the effect of reducing CO2 emission is still limited.

[0004] The existing sintering process production flow is as shown in Figure 5 The sintering raw material is mainly composed of iron ore, flux, fuel, the sintering fuel is mainly the fossil fuel coke powder, and the proportion in the sintering raw material is about 3-5%. After the various components of sintering raw material are fully mixed and granulated, the distributor is uniformly laid on the sintering trolley. The trolley advances uniformly from left to right, when the trolley advances to the ignition heat preservation furnace, the ignition heat preservation furnace is ignited by the ignition burner, the coke powder on the surface of sintering raw material is ignited, then under the action of the downdraught negative pressure under the trolley, the air above the trolley is continuously sucked into the material layer, the combustion zone in the material layer is transferred from top to bottom, and the whole sintering process is completed. The high-temperature flue gas is sucked by the main downdraught machine into the large flue under the trolley, the temperature reaches 900 DEG C or above, and after waste heat utilization and desulfurization and denitrification, it is discharged into the atmosphere.

[0005] The fuel of the traditional sintering process is still mainly fossil fuel, the coke powder is added in the sintering raw material, the coke oven gas and the blast furnace gas used for sintering ignition are essentially derived from coal, and a large amount of CO2 needs to be discharged to the outside in the production of the sintered ore. At present, some low-carbon sintering methods for replacing the sintering fossil fuel by mixing some biomass appear in the market, which generally directly mixes the biomass fuel with the iron ore, and the distribution of the biomass in the sintering raw material is easy to segregate in the uniform mixing of the raw material, so that the heat distribution in the material layer is uneven. And a large amount of volatile components in the biomass are not combusted in time and are taken away by the large flue, so that the heat in the material layer is insufficient, and the combustible gas in the flue gas is overproof. The direct mixing of the biomass in the raw material has limited effect on the carbon reduction of the sintering, and also affects the quality of the sintered ore. Practical new type content

[0006] In view of the problem that the biomass is easy to segregate in the mixing process in the low-carbon sintering method for replacing the fossil fuel, and further causes the uneven heat distribution in the sintering material layer, and a large amount of volatile components in the biomass are not combusted in time, so that the heat in the material layer is insufficient, the utility model provides a low-carbon sintering system, the biomass is crushed and sieved, then the biomass fuel particles of different particle sizes are sent to different sintering processes, so that the biomass is fully utilized and low-carbon sintering is realized. According to the different basic characteristics of the biomass of different particle sizes, the inventor studies the characteristics of different biomass properties and the requirements of the sintering process, and couples the biomass of different properties with different sintering processes, so as to improve the utilization efficiency of the biomass in the sintering process, and further achieve the purposes of reducing the use of fossil energy and reducing carbon emission, and realizing low-carbon sintering.

[0007] According to the first embodiment of the utility model, a low-carbon sintering method is provided.

[0008] A low-carbon sintering method, the method comprises the following steps:

[0009] 1) biomass pretreatment: the biomass is crushed and sieved to obtain large-particle biomass, medium-particle biomass and small-particle biomass; the medium-particle biomass is subjected to gasification treatment to obtain combustible gas and gasification residue;

[0010] 2) sintering burdening and distributing: the sintering raw material is burdened to obtain sintering material, the sintering material is distributed on the sintering machine trolley, then dry treatment is optionally performed or not, and finally the large-particle biomass is laid on the material surface of the sintering material to obtain sintering material containing biomass;

[0011] 3) sintering process: the sintering mixture containing biomass is forwarded on a sintering pallet and sequentially subjected to ignition, roasting and cooling processes to obtain the sintered product; in the ignition process, small-particle biomass is sent to the ignition burner as ignition fuel; in the roasting process, combustible gas is blown onto the surface of the sintering mixture to participate in the roasting.

[0012] Preferably, the particle size of the large-particle biomass in step 1) is [a, b], the particle size of the medium-particle biomass is [c, a), and the particle size of the small-particle biomass is (0, c).

[0013] Preferably, the particle size of the large-particle biomass in step 1) is [a, b], the particle size of the medium-particle biomass is [c, a), and the particle size of the small-particle biomass is (0, c).

[0014] Preferably, the particle size of the large-particle biomass in step 1) is [a, b], the particle size of the medium-particle biomass is [c, a), and the particle size of the small-particle biomass is (0, c).

[0015] Preferably, the particle size of the large-particle biomass in step 1) is [a, b], the particle size of the medium-particle biomass is [c, a), and the particle size of the small-particle biomass is (0, c).

[0016] Preferably, the particle size of the large-particle biomass in step 1) is [a, b], the particle size of the medium-particle biomass is [c, a), and the particle size of the small-particle biomass is (0, c).

[0017] Preferably, the particle size of the large-particle biomass in step 1) is [a, b], the particle size of the medium-particle biomass is [c, a), and the particle size of the small-particle biomass is (0, c).

[0018] Preferably, the particle size of the large-particle biomass in step 1) is [a, b], the particle size of the medium-particle biomass is [c, a), and the particle size of the small-particle biomass is (0, c).

[0019] Preferably, the particle size of the large-particle biomass in step 1) is [a, b], the particle size of the medium-particle biomass is [c, a), and the particle size of the small-particle biomass is (0, c).

[0020] Preferably, the particle size of the large-particle biomass in step 1) is [a, b], the particle size of the medium-particle biomass is [c, a), and the particle size of the small-particle biomass is (0, c).

[0021] Preferably, the particle size of the large-particle biomass in step 1) is [a, b], the particle size of the medium-particle biomass is [c, a), and the particle size of the small-particle biomass is (0, c).

[0022] Preferably, the particle size of the large-particle biomass in step 1) is [a, b], the particle size of the medium-particle biomass is [c, a), and the particle size of the small-particle biomass is (0, c).

[0023] Preferably, the drying treatment in step 2) is that high-temperature hot air with a temperature not lower than 300 DEG C is introduced into the sintering pallet to contact the sintering material to realize heat exchange drying; preferably, the high-temperature hot air with a temperature not lower than 300 DEG C is hot air generated in the cooling process and / or flue gas obtained in the gasification process.

[0024] Preferably, the method further comprises: 4) after the gasification residue obtained in step 1) is subjected to a forming treatment, forming residue is obtained, and the forming residue is used as one of the sintering raw materials to participate in batching.

[0025] Preferably, the forming treatment is specifically that the obtained gasification residue is subjected to extrusion exhaust and crushing.

[0026] Preferably, the extrusion pressure in the extrusion exhaust process is 15-30 MPa, preferably 20-28 MPa.

[0027] Preferably, the particle size of the forming residue obtained after the crushing is 2-7 mm, preferably 3-5 mm.

[0028] According to the second embodiment of the utility model, a biomass fractionation treatment process for a low-carbon sintering method is provided.

[0029] A biomass fractionation treatment process for a low-carbon sintering method, the biomass fractionation treatment process comprising: a) according to the properties of the biomass, controlling the gasification reaction parameters so that the volatile content in the gasification residue is not higher than a set value. Further preferably, the carbon content in the gasification residue is also not lower than a set value.

[0030] Preferably, the volatile content in the gasification residue is not higher than a set value is that the volatile content in the gasification residue is not higher than 8%, preferably not higher than 5%; and the carbon content in the gasification residue is higher than a set value is that the carbon content in the gasification residue is not lower than 20%, preferably not lower than 25%.

[0031] Preferably, the gasification process is carried out in a fixed bed reactor, and the control of the gasification reaction parameters is that:

[0032] At a given gasification temperature, the theoretical gasification time required for the carbon content in the gasification residue to equal the set value is calculated as:

[0033]

[0034] In the formula, C0 is the initial carbon content in the medium-granularity biomass, %; C1 is the set value of the carbon content in the gasification residue, %; L is the particle size of the medium-granularity biomass, mm; M is the moisture content in the biomass, %; T1 is the gasification temperature, DEG C; t ′1 is the time required for heating to the carbon reaction in the biomass; α and η are both adjustment factors, wherein the value range of α is 0.20-0.30, and the value range of η is 0.10-0.20.

[0035] At the same gasification temperature, the theoretical gasification time required for the volatile content in the gasification slag to equal the set value is calculated as:

[0036]

[0037] In the formula, V0 is the initial volatile content in the medium-granularity biomass, %; V1 is the set value of the volatile content in the gasification slag, %; L is the particle size of the medium-granularity biomass, mm; M is the moisture content in the biomass, %; T1 is the gasification temperature, ℃; t ′ 2 is the time required for heating to the volatile reaction in the biomass; γ and μ are both adjustment factors, wherein the value range of γ is 0.08-0.15, and the value range of μ is 0.10-0.20.

[0038] The controlled actual gasification time is:

[0039] When t2≤t1, the temperature meets the gasification condition, and according to (Formula 1) and (Formula 2), the controlled actual gasification time t at the temperature is: t2≤t≤t1; when t2>t1, the controlled actual gasification time t at the temperature is: t≥t2.

[0040] Preferably, the process further comprises: b) detecting the volatile content and the carbon content in the gasification slag, and returning the gasification slag with excessively high volatile content and carbon content to the gasification process of the medium-granularity biomass for re-gasification.

[0041] Preferably, the process further comprises: c) controlling the mass distribution ratio of the obtained large-granularity biomass, medium-granularity biomass and small-granularity biomass in the biomass crushing and screening classification process, so as to reduce the carbon emission while meeting the normal operation requirement of the sintering process; and the specific steps include:

[0042] ci) establishing a dynamic mathematical model of the mass distribution ratio of the large-granularity biomass, medium-granularity biomass and small-granularity biomass while meeting the normal operation requirement of the sintering process and reducing the carbon emission:

[0043]

[0044] In Equation 3, A is the proportion of small-particle biomass to the total biomass mass (%); B is the proportion of medium-particle biomass to the total biomass mass (%); C is the proportion of large-particle biomass to the total biomass mass (%); where A+B+C<1; δ is a dimensionless correction coefficient, ranging from 1 to 3; Q is the proportion of biomass mass that becomes gasification slag during gasification to the mass of medium-particle biomass (%); P is the proportion of biomass mass that becomes combustible gas during gasification to the mass of medium-particle biomass (%); T2 is the ignition temperature (°C); F is the iron ore grade (%); and Y is the carbon-saving ratio after adopting the biomass graded and graded treatment coupled with sintering process.

[0045] cii) Based on the relationship curve between the mass change of large-particle biomass laid on the sintering surface and the ignition temperature, establish the relationship between the amount of large-particle biomass laid and the ignition temperature:

[0046] T2 = 1050 - β*(0.5 + 5*D) 0.1 *In(1+5*D)……(Equation 4)

[0047] In Equation 4, β is a coefficient related to the type of ore raw material, with a value range of 50 to 600, preferably 200 to 600, and more preferably 300 to 600; D is the percentage of the mass of large-particle biomass laid on the sintering surface to the total mass of the sintering material, with a value range of 1% to 15%, preferably 2% to 10%, and more preferably 3% to 8%; the minimum ignition temperature under the target working condition is calculated based on Equation 4; combining Equations 3 and 4, the minimum percentage of the mass of large-particle biomass laid on the sintering surface to the total mass of the sintering material, and the mass of small-particle biomass required under the optimal energy consumption condition for sintering ignition are first calculated, then the minimum mass distribution ratio of large-particle biomass and the minimum mass distribution ratio of small-particle biomass are obtained, and finally, the mass distribution ratio of medium-particle biomass is calculated under the premise of satisfying the minimum mass distribution ratio of large-particle biomass and the minimum mass distribution ratio of small-particle biomass. Preferably, the percentage of the mass of large-particle biomass laid on the sintering surface to the total mass of the sintering material has an optimal range, that is, the optimal value range of D is 3% to 6%.

[0048] Preferably, the total mass of biomass is 1% to 2.6% of the mass of sinter, the value of A is 5% to 12%, the value of B is 55% to 75%, the value of C is 18% to 28%, and A+B+C≤1; the value of P is 60% to 75%, the value of Q is 25% to 40%, and P+Q=1.

[0049] According to a third embodiment of the present invention, a low-carbon sintering system is provided.

[0050] A low-carbon sintering system includes a sintering machine, a batching device, a feeding device, an ignition burner, a crushing device, a screening device, a gasification device, an annular cooler, and a jetting device. The sintering machine is divided into a drying section, a preheating section, and a calcining section according to its operating direction. The ignition burner is located in an ignition furnace situated above and downstream of the preheating section. The material outlet of the batching device is connected to the material inlet of the feeding device. The material outlet of the feeding device is located at the feed end of the sintering machine. The jetting device is positioned above the calcining section. The discharge end of the sintering machine is connected to the feed end of the annular cooler.

[0051] The material outlet of the crushing device is connected to the material inlet of the screening device. The large particle material outlet of the screening device is connected to the material inlet of the feeding device, the medium particle material outlet of the screening device is connected to the material inlet of the gasification device, and the small particle material outlet of the screening device is connected to the material inlet of the ignition burner. The gas outlet of the gasification device is connected to the fuel inlet of the injection device. The length of the sintering machine is 1–2000 m, preferably 2–1500 m, and more preferably 3–1000 m. The length of the annular cooler is 1–800 m.

[0052] Preferably, the screening device is further provided with an oversize material outlet, which is connected to the material inlet of the crushing device.

[0053] Preferably, the system also includes a forming device, wherein the solid outlet of the gasification device is connected to the material inlet of the forming device, and the material outlet of the forming device is connected to the material inlet of the batching device.

[0054] Preferably, the gas inlet of the drying section is connected to the high-temperature gas outlet of the annular cooler or the low-temperature medium outlet of the gasification device via a pipeline.

[0055] Preferably, the ignition burner includes a combustion air duct and a biomass duct. The inlet end of the combustion air duct is connected to an oxygen-containing gas source, and the outlet end of the combustion air duct is connected to the furnace of the ignition furnace. The feed end of the biomass duct is simultaneously connected to the fine particle material outlet of the screening device and the carrier gas source, and the discharge end of the biomass duct is connected to the furnace of the ignition furnace. The bottom of the furnace is connected to the upper downstream side of the preheating section.

[0056] Preferably, the discharge section of the biomass pipeline includes a gas discharge channel and a solid discharge channel sleeved outside the gas discharge channel.

[0057] Preferably, the combustion air duct includes a central air duct and a secondary air duct that are not interconnected. The inlet ends of both the central and secondary air ducts are connected to an oxygen-containing gas source. The central air duct is fitted inside the cavity of the gas discharge channel along its axis, while the secondary air duct is fitted outside the solid discharge channel. The outlet ends of both the central and secondary air ducts are connected to the furnace chamber of the ignition furnace.

[0058] Preferably, the ignition burner further includes a swirl mechanism, which is disposed at the outlet end of the secondary air duct and / or the gas discharge channel. Preferably, the swirl mechanism is a swirl blade.

[0059] Preferably, the carrier gas source is the gas outlet of the drying section.

[0060] Preferably, the gasification device includes a kiln body and a heat exchange device extending into the kiln body but not communicating with it. The kiln body comprises a kiln head, a kiln body, and a kiln tail connected in series. The kiln head and kiln tail are fixedly arranged, while the kiln body can rotate along its axis. A gas-solid inlet is provided at the upper part of the kiln head, which is connected via pipes to both the medium-particle material outlet of the screening device and a high-humidity oxygen-containing gas source. A gas outlet is provided at the upper part of the kiln tail, which is connected via pipes to the fuel inlet of the injection device. A solid outlet is provided at the lower part of the kiln tail, which is connected via a conveyor belt to the material inlet of the forming device or the material inlet of the batching device. Preferably, the high-humidity oxygen-containing gas source is the gas outlet of the drying section.

[0061] Preferably, the heat exchange device includes an outer cylinder and an inner cylinder. The outer cylinder passes through the kiln head, kiln body, and kiln tail sequentially along the axial direction. An inner cylinder is inserted into each end of the outer cylinder, and the inserted end of the inner cylinder extends along the axis of the outer cylinder to the middle of the inner cylinder cavity. High-temperature medium inlets are provided at both ends of the outer cylinder located outside the kiln body, and medium return ports are provided at the ends of the inner cylinder located inside the outer cylinder. The inner cylinder is connected to the outer cylinder through the medium return ports. Low-temperature medium outlets are provided on the inner cylinder located outside the outer cylinder. Preferably, the high-temperature medium inlets are connected to the sintering flue. Preferably, a blind plate is also provided in the middle of the outer cylinder cavity, which divides the outer cylinder cavity into two non-communicating sections. The two inner cylinders are located in the two non-communicating sections respectively.

[0062] Preferably, there are 1 to 8 heat exchange devices evenly distributed inside the kiln body.

[0063] Preferably, the gasification device further includes a water supply pipe, the inlet end of which is connected to a new water source, and the outlet end of which extends through the kiln head and into the kiln body. Multiple atomizing nozzles are provided on the outlet section of the water supply pipe.

[0064] Preferably, the kiln body is inclined with a higher kiln head and a lower kiln tail. Preferably, the inclination angle of the kiln body is 2 to 8°, and more preferably 3 to 6°.

[0065] In existing technologies, woody plants from urban landscaping solid waste, such as pine and camphor, are preferred for biomass addition to sintering, followed by agricultural straw. A common characteristic of these materials is their high volatile matter content, typically reaching around 70%. Furthermore, biomass raw materials are irregularly shaped, while sintering requires fuel with low volatile matter content (<5%) and strong exothermic properties. Therefore, biomass cannot be directly added to the sintering process. Directly mixing biomass into the sintering raw materials does not meet the low volatile matter requirement, easily leading to uneven heat distribution or insufficient heat in the sintering bed.

[0066] In this invention, biomass is crushed and screened into three grades. Large-particle biomass fuel is arranged on the surface of the sintering bed, replacing part of the coke powder. Medium-particle biomass fuel has a moderate particle size and high reactivity, used for gasification to produce combustible gas. Small-particle biomass fuel has a high specific surface area, low specific gravity, and fast combustion speed, and is fed into the ignition burner as ignition fuel. This invention classifies biomass into multiple grades according to particle size and adds biomass fuel of different particle sizes to the sintering process using different processes, which can effectively improve the utilization rate of biomass and achieve low-carbon sintering. In addition, biomass with excessively large particle size (i.e., ultra-large-particle biomass fuel) can be returned to the crushing step for re-crushing, further improving the utilization rate of biomass.

[0067] In this invention, based on extensive experiments, a general range for classifying biomass fuel particle size grades was obtained, as follows: Since the particle size of coke powder in the sintering raw material is approximately 2–5 mm, medium-particle biomass fuel is divided into [a, b] with similar particle sizes. Biomass fuel within this particle size range, when laid on the surface of the sintering material layer, exhibits better reactivity than coke powder and is easier to ignite. It can be rapidly ignited after entering the preheating section, improving ignition efficiency and reducing ignition energy consumption. Furthermore, biomass with a particle size range of [c, a) has moderate particle size and good reactivity, making it suitable for gasification to produce combustible gases. The remaining biomass fuel with a particle size of (0, c) is used as ignition fuel for the burner. Specifically, a ranges from 1 to 3 mm; b ranges from 4 to 8 mm; and c ranges from 0.3 to 0.7 mm.

[0068] Through experimental research, the inventors discovered that medium-sized particulate biomass (e.g., biomass with a particle size range of 0.5–2 mm) has a moderate particle size and good reactivity, making it most suitable for gasification to produce combustible gas (controlling the volatile matter and carbon content in the treated material). In this invention, the gasification temperature of the medium-sized particulate biomass fuel is above 700℃ (preferably 800℃). Theoretically, the higher the gasification temperature, the higher the gasification reaction rate and the higher the carbon conversion rate. The gasification reaction uses steam and oxygen as gasifying agents, and the main reactions are as follows:

[0069] C + H₂O = CO + H₂

[0070] C + O₂ = 2CO

[0071] The combustible gas obtained from gasification mainly consists of H2, CO, and other combustible gases. Injecting this gas into the sintering material layer provides supplemental heating to the sintering surface, effectively reducing the consumption of solid carbon in the sintering material layer and achieving low-carbon sintering. Preferably, the heat required for the gasification reaction comes from the high-temperature flue gas in the sintering flue, with a temperature >700℃, and indirect heat exchange (such as a partition wall heat exchange) is used. Alternatively, the water vapor and oxygen can be sourced from the high-humidity hot air dried in other processes (e.g., the high-humidity hot air generated in the drying section), which contains abundant water vapor and air and has a high temperature. Utilizing readily available high-humidity hot air reduces the consumption of new water and improves the waste heat utilization rate of the high-humidity hot air. If the moisture content in the high-humidity hot air is insufficient, additional new water needs to be added.

[0072] In this invention, to ensure sufficient H2 in the combustible gas and to place the medium-particle biomass fuel in an atmosphere of H2 and CO, the gas-solid mass ratio of the total mass of water vapor and oxygen to the residual biomass is limited to 0.4–0.8:1. Furthermore, by adjusting the water vapor content in the high-humidity hot air and the amount of fresh water replenishment, the volume ratio of water vapor to oxygen during the gasification reaction is maintained within the range of 1–2:1. Ensuring sufficient H2 content in the combustible gas improves the cleanliness of the combustion products, while also increasing the heat released by hydrogen combustion, thereby improving the energy utilization efficiency of the combustible gas.

[0073] In this invention, the reaction vessel for the gasification process can optionally be a suspended bed reactor or a fixed bed reactor.

[0074] In this invention, after gasification, medium-particle biomass fuel yields combustible gas and gasification slag. The main component of the gasification slag is unreacted carbon from the biomass, with a carbon content generally between 20% and 30% and volatile matter <5%. Compared to the biomass raw material, the volatile matter and carbon content of the gasification slag are significantly reduced, resulting in low reactivity. Preferably, since the gasification slag still has a well-developed porous structure, to further reduce its reactivity and improve the utilization rate of biomass, this invention employs an extrusion molding method and further limits the time, pressure, and other parameters during the extrusion molding process to eliminate the porosity of the gasification slag, forming dense gasification slag molded fuel carbon. After crushing, carbon fuel is obtained. The obtained carbon fuel has low volatile matter, slow exothermic reaction, and high density, meeting the requirements for sintering fuel. It can be directly mixed with sintering raw materials to replace part of the coke powder and reduce the amount of fossil fuel used.

[0075] In this invention, to achieve a carbon content of no less than 20% and a volatile matter content of no more than 5% in the gasification slag, the present invention calculates the gasification time t1 and the volatile matter content t2 at the critical points based on parameters such as particle size, moisture content, and carbon content of the medium-sized particulate biomass. If t2 ≤ t1, it indicates that there exists a gasification time at this temperature that simultaneously satisfies the requirements for carbon content and volatile matter content, and the actual gasification time t is set to satisfy t2 ≤ t ≤ t1; when t2 > t1, since a volatile matter content below the set value is a mandatory requirement and a carbon content above the set value is a preferred requirement, t must be greater than or equal to t2. Therefore, the actual gasification time t at this temperature should be: t ≥ t2.

[0076] This invention further proposes a dynamic mathematical model for the mass distribution ratio of large-particle biomass, medium-particle biomass, and small-particle biomass. Simultaneously, based on the relationship curve between the mass of large-particle biomass laid on the sintering surface and the ignition temperature, a formula for the relationship between the amount of large-particle biomass laid and the ignition temperature is established. According to formula (4), the minimum ignition temperature under the target operating condition can be calculated. Combining formulas (3) and (4), the minimum percentage of the mass of large-particle biomass laid on the sintering surface relative to the total mass of the sintering material, and the required mass of small-particle biomass under optimal energy consumption conditions for sintering ignition are first calculated. Then, the minimum mass distribution ratios of large-particle biomass and small-particle biomass are obtained. Finally, under the premise of satisfying the minimum mass distribution ratios of large-particle biomass and small-particle biomass, the mass distribution ratio of medium-particle biomass is calculated. Furthermore, regarding the values ​​of P and Q: According to Equation 3, the larger the value of P, the greater the carbon saving ratio. Increasing P can be achieved by raising the gasification temperature and residence time, but P cannot be increased indefinitely. When the temperature and residence time reach a certain level, P will no longer increase, at which point P reaches its maximum value. Preferably, the total mass of biomass is 1% to 2.6% of the sinter mass, A ranges from 5% to 12%, B ranges from 55% to 75%, C ranges from 18% to 28%, and A+B+C<1; P ranges from 60% to 75%, Q ranges from 25% to 40%, and P+Q=1.

[0077] In this invention, while meeting the requirements of the ignition process, the maximum carbon saving is achieved by controlling the mass distribution ratio of large, medium, and small biomass particles. Through iterative calculations, the mass distribution ratio of these three particles that achieves the maximum carbon saving is determined. Then, the crushing, screening, and grading processes are controlled to obtain the required specific mass distribution ratio of these three particles.

[0078] In this invention, a drying section is set up upstream of the preheating section according to the running direction of the sintering trolley, and ambient air (preferably hot air discharged from the annular cooler or low-temperature flue gas from the sintering flue used for hydrogen production after gasification) is introduced to dry the sintering raw materials, thereby removing the moisture added during the mixing and granulation process, reducing the energy consumed in the subsequent process, and avoiding the formation of an overly wet zone in the sintering material layer, which would affect the permeability of the sintering material layer.

[0079] This invention also proposes an ignition burner structure, which delivers gas to the sintering material surface and ignites it through a combustion air duct and a biomass duct. Preferably, since biomass undergoes pyrolysis at temperatures above 300°C, and the burner is located below the high temperature (850°C~1050°C) of the sintering furnace, the internal temperature of the burner is likely to exceed 300°C, causing the biomass to pyrolyze. This invention sets the biomass duct as an inner solid discharge channel and a gas discharge channel surrounding the solid discharge channel. After the biomass powder undergoes pyrolysis, it enters the burner tangentially, generating a swirling flow. Due to the density difference between the gas and the solid, the solid biomass powder moves towards the outer center and enters the solid discharge channel, while the gas moves closer to the center, thus generating a certain amount of swirling separation. The gas enters the gas discharge channel, enters the ignition furnace, mixes with the combustion gas, and burns. It is also connected to the bottom of the ignition furnace and the upper downstream side of the preheating section to complete the sintering ignition. Preferably, the combustion air duct is divided into a central air duct and a secondary air duct. The outlet of the central air duct is located inside the gas discharge channel, and the outlet of the secondary air duct is fitted outside the solid discharge channel. Under the combined action of the central and secondary air, the combustion air can be fully mixed with the biomass powder and pyrolysis gas. Furthermore, a swirling mechanism is installed in the gas discharge channel and / or the secondary air duct. The swirling combustion air entrains the biomass powder, pyrolysis gas, and internal combustion air, causing them to mix intensely, thereby achieving efficient combustion.

[0080] This invention also proposes a gasification device structure, which includes a kiln body and a heat exchanger. Indirect heat exchange provides heat for biomass gasification, increasing the gasification temperature. Biomass and high-humidity oxygen-containing gas enter through the gas-solid inlet. After the reaction is completed inside the kiln, the generated gasified gas exits through the gas outlet, while the gasified slag moves towards the kiln tail under the rotation of the kiln body and is finally discharged through the solid outlet. Alternatively, the kiln body can be designed with a higher kiln head and lower kiln tail, combined with a rotatable kiln body, which facilitates the discharge of gasified slag. Preferably, the heat exchanger is a sleeve-type structure, with hot flue gas entering through the outer cylinder, indirectly contacting the biomass, and exiting through the inner cylinder after heat exchange, reducing the contact between biomass and low-temperature flue gas. More preferably, in addition to the high-humidity oxygen-containing gas carrying a large amount of water vapor, a water supply pipe is also provided. Water enters the kiln and undergoes a secondary reaction with the biomass, increasing the gasification intensity and simultaneously increasing the H2 production in the gasified gas.

[0081] In this utility model, the formulas are obtained by the inventors based on experimental and engineering applications. All calculations are numerical values ​​converted according to the specified units. The converted values ​​are substituted into the formulas to obtain the results (after converting the units of each parameter, only the numerical values ​​are substituted into the formulas for calculation, not the units; the units are only used to adjust the magnitude of the numerical values).

[0082] Compared with the prior art, the present invention has the following beneficial effects: The low-carbon sintering system provided by the present invention has a simple structure and can realize the separate utilization of biomass after crushing according to different particle sizes. At the same time, the structure of the ignition burner enables the combustion gas and fuel to be mixed quickly and evenly, achieving efficient combustion. Furthermore, the gasification device increases the gasification intensity and the H2 production in the gasified gas, making it highly practical. Attached Figure Description

[0083] Figure 1 A schematic diagram of a low-carbon sintering system provided by this utility model.

[0084] Figure 2 This is another structural schematic diagram of a low-carbon sintering system provided by this utility model.

[0085] Figure 3 This is a schematic diagram of the structure of an ignition burner in a low-carbon sintering system provided by this utility model.

[0086] Figure 4 This is a schematic diagram of the gasification device in a low-carbon sintering system provided by this utility model.

[0087] Figure 5 This is a flowchart of the existing sintering process.

[0088] Figure reference numerals: 1: Sintering machine; 101: Drying section; 102: Preheating section; 103: Calcination section; 2: Batching device; 3: Material distribution device; 4: Ignition burner; 401: Combustion air duct; 4011: Central air duct; 4012: Secondary air duct; 402: Biomass duct; 4021: Gas discharge channel; 4022: Solid discharge channel; 403: Cyclone mechanism; 5: Crushing device; 6: Screening device; 7: Gasification device; 701: Kiln body; 70 11: Kiln head; 7012: Kiln body; 7013: Kiln tail; 7014: Gas-solid inlet; 7015: Gas outlet; 7016: Solid outlet; 702: Heat exchanger; 7021: High-temperature medium inlet; 7022: Low-temperature medium outlet; 7023: Outer cylinder; 7024: Inner cylinder; 7025: Medium return port; 7026: Blind flange; 7027: Water supply pipe; 7028: Atomizing nozzle; 8: Circular cooler; 9: Spraying device; 10: Molding device. Detailed Implementation

[0089] The technical solution of this utility model is illustrated below. The scope of protection of this utility model includes, but is not limited to, the following embodiments.

[0090] A low-carbon sintering system includes a sintering machine 1, a batching device 2, a feeding device 3, an ignition burner 4, a crushing device 5, a screening device 6, a gasification device 7, an annular cooler 8, and a jetting device 9. The sintering machine 1 is divided into a drying section 101, a preheating section 102, and a calcining section 103 according to its operating direction. The ignition burner 4 is located in an ignition furnace situated above and downstream of the preheating section 102. The material outlet of the batching device 2 is connected to the material inlet of the feeding device 3. The material outlet of the feeding device 3 is located at the feed end of the sintering machine 1. The jetting device 9 is located above the calcining section 103. The discharge end of the sintering machine 1 is connected to the feed end of the annular cooler 8.

[0091] The material outlet of the crushing device 5 is connected to the material inlet of the screening device 6. The large particle material outlet of the screening device 6 is connected to the material inlet of the feeding device 3, the medium particle material outlet of the screening device 6 is connected to the material inlet of the gasification device 7, and the small particle material outlet of the screening device 6 is connected to the material inlet of the ignition burner 4. The gas outlet of the gasification device 7 is connected to the fuel inlet of the injection device 9.

[0092] Preferably, the screening device 6 is further provided with an oversize material outlet, which is connected to the material inlet of the crushing device 5.

[0093] Preferably, the system further includes a forming device 10, the solid outlet of the gasification device 7 is connected to the material inlet of the forming device 10, and the material outlet of the forming device 10 is connected to the material inlet of the batching device 2.

[0094] Preferably, the gas inlet of the drying section 101 is connected to the high-temperature gas outlet of the annular cooler 8 or the low-temperature medium outlet of the gasification device 7 via a pipeline.

[0095] Preferably, the ignition burner 4 includes a combustion air duct 401 and a biomass duct 402. The inlet end of the combustion air duct 401 is connected to an oxygen-containing gas source, and the outlet end of the combustion air duct 401 is connected to the furnace of the ignition furnace. The feed end of the biomass duct 402 is simultaneously connected to the fine particle material outlet of the screening device 6 and a carrier gas source, and the discharge end of the biomass duct 402 is connected to the furnace of the ignition furnace.

[0096] Preferably, the discharge section of the biomass pipeline 402 includes a gas discharge channel 4021 and a solid discharge channel 4022 sleeved outside the gas discharge channel 4021.

[0097] Preferably, the combustion air duct 401 includes a central air duct 4011 and a secondary air duct 4012 that are not interconnected. The inlet ends of both the central air duct 4011 and the secondary air duct 4012 are connected to an oxygen-containing gas source. The central air duct 4011 is sleeved within the cavity of the gas discharge channel 4021 along its axis, and the secondary air duct 4012 is sleeved outside the solid discharge channel 4022. The outlet ends of both the central air duct 4011 and the secondary air duct 4012 are connected to the furnace chamber of the ignition furnace.

[0098] Preferably, the ignition burner 4 further includes a swirl mechanism 403, which is disposed at the outlet end of the secondary air duct 4012 and / or the gas outlet channel 4021. Preferably, the swirl mechanism 403 is a swirl blade.

[0099] Preferably, the carrier gas source is the gas outlet of the drying section 101.

[0100] Preferably, the gasification device 7 includes a kiln body 701 and a heat exchange device 702 extending into the kiln body 701 but not communicating with it. The kiln body 701 includes a kiln head 7011, a kiln body 7012, and a kiln tail 7013 connected in series. The kiln head 7011 and kiln tail 7013 are fixedly arranged, while the kiln body 7012 can rotate along its axis. A gas-solid inlet 7014 is provided at the upper part of the kiln head 7011, and the gas-solid inlet 7014 is simultaneously connected to the medium-particle material outlet of the screening device 6 and a high-humidity oxygen-containing gas source via a pipe. A gas outlet 7015 is provided at the upper part of the kiln tail 7013, and the gas outlet 7015 is connected to the fuel inlet of the injection device 9 via a pipe. A solid outlet 7016 is provided at the lower part of the kiln tail 7013, and the solid outlet 7016 is connected to the material inlet of the forming device 10 or the material inlet of the batching device 2 via a conveyor belt. Preferably, the high-humidity oxygen-containing gas source is the gas outlet of the drying section 101.

[0101] Preferably, the heat exchange device 702 includes an outer cylinder 7023 and an inner cylinder 7024. The outer cylinder 7023 sequentially passes through the kiln head 7011, the kiln body 7012, and the kiln tail 7013 along the axial direction. An inner cylinder 7024 is inserted into each end of the outer cylinder 7023, and the inserted end of the inner cylinder 7024 extends along the axis of the outer cylinder 7023 to the middle of the inner cylinder cavity. High-temperature medium inlets 7021 are provided at both ends of the outer cylinder 7023 located outside the kiln body 701, and medium return ports 7025 are provided at the ends of the inner cylinder 7024 located inside the outer cylinder 7023. The inner cylinder 7024 is connected to the outer cylinder 7023 through the medium return ports 7025. Low-temperature medium outlets 7022 are provided on the inner cylinder 7024 located outside the outer cylinder 7023. Preferably, the high-temperature medium inlet 7021 is connected to the sintering flue. Preferably, a blind plate 7026 is provided in the middle of the outer cylinder 7023 cavity, which divides the outer cylinder 7023 cavity into two non-communicating sections, and the two inner cylinders 7024 are located in the two non-communicating sections respectively.

[0102] Preferably, one to eight heat exchange devices 702 are evenly distributed inside the kiln body 701.

[0103] Preferably, the gasification device 7 further includes a water supply pipe 7027, the inlet end of which is connected to a new water source, the outlet end of which extends through the kiln head 7011 and into the kiln body 7012, and multiple atomizing nozzles 7028 are provided on the outlet section of the water supply pipe 7027.

[0104] Preferably, the kiln body 701 is inclined with the kiln head 7011 higher and the kiln tail 7013 lower. Preferably, the inclination angle of the kiln body 701 is 2 to 8°, and more preferably 3 to 6°.

[0105] Example 1

[0106] A low-carbon sintering system, such as Figures 1-4 As shown, the sintering system includes a sintering machine 1, a batching device 2, a feeding device 3, an ignition burner 4, a crushing device 5, a screening device 6, a gasification device 7, an annular cooler 8, and a jetting device 9. The sintering machine 1 is divided into a drying section 101, a preheating section 102, and a calcining section 103 according to its operating direction. The ignition burner 4 is located in an ignition furnace located above and downstream of the preheating section 102. The material outlet of the batching device 2 is connected to the material inlet of the feeding device 3. The material outlet of the feeding device 3 is located at the feed end of the sintering machine 1. The jetting device 9 is located above the calcining section 103. The discharge end of the sintering machine 1 is connected to the feed end of the annular cooler 8.

[0107] The material outlet of the crushing device 5 is connected to the material inlet of the screening device 6. The large particle material outlet of the screening device 6 is connected to the material inlet of the feeding device 3, the medium particle material outlet of the screening device 6 is connected to the material inlet of the gasification device 7, and the small particle material outlet of the screening device 6 is connected to the material inlet of the ignition burner 4. The gas outlet of the gasification device 7 is connected to the fuel inlet of the injection device 9.

[0108] Example 2

[0109] The embodiment 1 is repeated, except that the screening device 6 is also provided with an oversize material outlet, which is connected to the material inlet of the crushing device 5.

[0110] Example 3

[0111] The system repeats Example 2, except that it also includes a forming device 10, the solid outlet of the gasification device 7 is connected to the material inlet of the forming device 10, and the material outlet of the forming device 10 is connected to the material inlet of the batching device 2.

[0112] The gas inlet of the drying section 101 is connected to the high-temperature gas outlet of the annular cooler 8 via a pipeline.

[0113] Example 4

[0114] The embodiment 3 is repeated, except that the ignition burner 4 includes a combustion air duct 401 and a biomass duct 402. The inlet end of the combustion air duct 401 is connected to an oxygen-containing gas source, and the outlet end of the combustion air duct 401 is connected to the furnace of the ignition furnace. The feed end of the biomass duct 402 is simultaneously connected to the fine particle material outlet of the screening device 6 and the carrier gas source, and the discharge end of the biomass duct 402 is connected to the furnace of the ignition furnace.

[0115] The discharge section of the biomass pipeline 402 includes a gas discharge channel 4021 and a solid discharge channel 4022 sleeved outside the gas discharge channel 4021.

[0116] Example 5

[0117] The embodiment 4 is repeated, except that the combustion air duct 401 includes a central air duct 4011 and a secondary air duct 4012 that are not interconnected. The inlet ends of both the central air duct 4011 and the secondary air duct 4012 are connected to an oxygen-containing gas source. The central air duct 4011 is sleeved within the cavity of the gas discharge channel 4021 along its axis, while the secondary air duct 4012 is sleeved outside the solid discharge channel 4022. The outlet ends of both the central air duct 4011 and the secondary air duct 4012 are connected to the furnace chamber of the ignition furnace.

[0118] Example 6

[0119] The embodiment 5 is repeated, except that the ignition burner 4 further includes a swirl mechanism 403, which is disposed at the outlet end of the secondary air duct 4012 and the gas discharge channel 4021. The swirl mechanism 403 consists of swirl blades.

[0120] The carrier gas source is the gas outlet of the drying section 101.

[0121] Example 7

[0122] The embodiment 6 is repeated, except that the gasification device 7 includes a kiln body 701 and a heat exchange device 702 that extends into the kiln body 701 but is not connected to it. The kiln body 701 includes a kiln head 7011, a kiln body 7012, and a kiln tail 7013 connected in series. The kiln head 7011 and kiln tail 7013 are fixedly arranged, while the kiln body 7012 can rotate along its axis. A gas-solid inlet 7014 is provided at the upper part of the kiln head 7011, and the gas-solid inlet 7014 is simultaneously connected to the medium-particle material outlet of the screening device 6 and a high-humidity oxygen-containing gas source via a pipe. A gas outlet 7015 is provided at the upper part of the kiln tail 7013, and the gas outlet 7015 is connected to the fuel inlet of the injection device 9 via a pipe. A solid outlet 7016 is provided at the lower part of the kiln tail 7013, and the solid outlet 7016 is connected to the material inlet of the forming device 10 via a conveyor belt. The high-humidity oxygen-containing gas source is the gas outlet of the drying section 101.

[0123] Example 8

[0124] The embodiment 7 is repeated, except that the heat exchange device 702 includes an outer cylinder 7023 and an inner cylinder 7024. The outer cylinder 7023 passes through the kiln head 7011, kiln body 7012, and kiln tail 7013 sequentially along the axial direction. An inner cylinder 7024 is inserted into each end of the outer cylinder 7023, and the inserted end of the inner cylinder 7024 extends along the axis of the outer cylinder 7023 to the middle of the inner cylinder cavity. High-temperature medium inlets 7021 are provided at both ends of the outer cylinder 7023 located outside the kiln body 701, and medium return ports 7025 are provided at the ends of the inner cylinder 7024 located inside the outer cylinder 7023. The inner cylinder 7024 is connected to the outer cylinder 7023 through the medium return ports 7025. Low-temperature medium outlets 7022 are provided on the inner cylinder 7024 located outside the outer cylinder 7023. The high-temperature medium inlets 7021 are connected to the sintering flue. A blind plate 7026 is also provided in the middle of the outer cylinder 7023 cavity. The blind plate 7026 divides the outer cylinder 7023 cavity into two non-communicating sections. The two inner cylinders 7024 are located in the two non-communicating sections respectively.

[0125] Example 9

[0126] Example 8 is repeated, except that two heat exchange devices 702 are evenly distributed inside the kiln body 701.

[0127] The gasification device 7 also includes a water supply pipe 7027. The inlet end of the water supply pipe 7027 is connected to a new water source. The outlet end of the water supply pipe 7027 extends through the kiln head 7011 and into the kiln body 7012. Five atomizing nozzles 7028 are installed on the outlet section of the water supply pipe 7027.

[0128] Example 10

[0129] Example 9 is repeated, except that the kiln body 701 is inclined with the kiln head 7011 higher and the kiln tail 7013 lower. The inclination angle of the kiln body 701 is 5°.

[0130] The sintering process using the low-carbon sintering system described in Embodiment 10 of this utility model is as follows:

[0131] 1) Biomass pretreatment: The biomass is crushed and screened by crushing device 5 and screening device 6 to obtain large-particle biomass, medium-particle biomass and small-particle biomass; the medium-particle biomass is gasified in gasification device 7 to obtain combustible gas and gasification residue.

[0132] 2) Sintering batching and feeding: The sintering raw materials are batched by the batching device 2 to obtain sintering material. The sintering material is first fed onto the trolley of the sintering machine 1 by the feeding device 3, then dried, and finally large particles of biomass are laid on the surface of the sintering material to obtain sintering material containing biomass.

[0133] 3) Sintering treatment: The sintering material containing biomass moves forward with the sintering trolley and passes through the ignition burner 4 for ignition, roasting and cooling treatment of the ring cooler 8 in sequence to obtain the sintered finished material; In the ignition process: small particles of biomass are fed into the ignition burner 4 as ignition fuel for ignition; In the roasting process, combustible gas is sprayed onto the surface of the sintering mixture by the injection device 9 to participate in roasting.

Claims

1. A low carbon sintering system, characterized by: The sintering system comprises a sintering machine (1), a batching device (2), a distributing device (3), an ignition burner (4), a crushing device (5), a screening device (6), a gasification device (7), a ring cooler (8), and a blowing device (9). According to the running direction of the sintering machine (1), the sintering machine (1) is sequentially divided into a drying section (101), a preheating section (102), and a roasting section (103). The ignition burner (4) is arranged in an ignition furnace above the downstream side of the preheating section (102). The material outlet of the batching device (2) is in communication with the material inlet of the distributing device (3). The material outlet of the distributing device (3) is arranged at the feeding end of the sintering machine (1). The blowing device (9) is arranged above the roasting section (103). The discharging end of the sintering machine (1) is in communication with the feeding end of the ring cooler (8). The material outlet of the crushing device (5) is in communication with the material inlet of the screening device (6). The large-particle material outlet of the screening device (6) is in communication with the material inlet of the distributing device (3), the medium-particle material outlet of the screening device (6) is in communication with the material inlet of the gasification device (7), and the small-particle material outlet of the screening device (6) is in communication with the material inlet of the ignition burner (4). The gas outlet of the gasification device (7) is in communication with the fuel inlet of the blowing device (9).

2. The system of claim 1, wherein: The screening device (6) is further provided with a sieve material outlet, which is in communication with the material inlet of the crushing device (5).

3. The system of claim 2, wherein: The system further comprises a forming device (10), the solid outlet of the gasification device (7) is in communication with the material inlet of the forming device (10), and the material outlet of the forming device (10) is in communication with the material inlet of the batching device (2).

4. The system of claim 3, wherein: The gas inlet of the drying section (101) is in communication with the high-temperature gas outlet of the ring cooler (8) or the low-temperature medium outlet of the gasification device (7) through a pipeline.

5. The system of any one of claims 1-4, wherein: The ignition burner (4) comprises a combustion air pipeline (401) and a biomass pipeline (402). The air inlet end of the combustion air pipeline (401) is in communication with an oxygen-containing gas source, and the air outlet end of the combustion air pipeline (401) is in communication with the hearth of the ignition furnace. The feeding end of the biomass pipeline (402) is in communication with the fine-particle material outlet of the screening device (6) and a carrier gas source, and the discharging end of the biomass pipeline (402) is in communication with the hearth of the ignition furnace.

6. The system of claim 5, wherein: The discharging section of the biomass pipeline (402) comprises a gas discharging channel (4021) and a solid discharging channel (4022) arranged outside the gas discharging channel (4021).

7. The system of claim 6, wherein: The combustion air pipe (401) comprises a central air pipe (4011) and a secondary air pipe (4012) which are not communicated with each other; the air inlet ends of the central air pipe (4011) and the secondary air pipe (4012) are communicated with the oxygen-containing gas source; the central air pipe (4011) is sleeved in the lumen of the gas discharge channel (4021) along the axis of the gas discharge channel (4021), and the secondary air pipe (4012) is sleeved outside the solid discharge channel (4022); the air outlet ends of the central air pipe (4011) and the secondary air pipe (4012) are communicated with the hearth of the ignition furnace.

8. The system of claim 7, wherein: The ignition burner (4) further comprises a cyclone mechanism (403) arranged at the air outlet end of the secondary air pipe (4012) and / or the gas discharge channel (4021).

9. The system of claim 8, wherein: The cyclone mechanism (403) is a cyclone vane.

10. The system of claim 8, wherein: The carrier gas source is the gas outlet of the drying section (101).

11. The system of any one of claims 1-4, 6-10, wherein: The gasification device (7) comprises a kiln body (701) and a heat exchange device (702) which extends into the interior of the kiln body (701) and is not communicated with the kiln body (701); wherein the kiln body (701) comprises a kiln head (7011), a kiln body (7012) and a kiln tail (7013) which are connected in series; the kiln head (7011) and the kiln tail (7013) are fixedly arranged, and the kiln body (7012) is rotatable along its axis; an air-solid inlet (7014) is arranged at the upper part of the kiln head (7011), and the air-solid inlet (7014) is communicated with the medium particle material outlet of the screening device (6) and the high-humidity oxygen-containing gas source through a pipeline; a gas outlet (7015) is arranged at the upper part of the kiln tail (7013), and the gas outlet (7015) is communicated with the fuel inlet of the injection device (9) through a pipeline; a solid outlet (7016) is arranged at the lower part of the kiln tail (7013), and the solid outlet (7016) is communicated with the material inlet of the molding device (10) or the material inlet of the batching device (2) through a conveying belt.

12. The system of claim 11, wherein: The high-humidity oxygen-containing gas source is the gas outlet of the drying section (101).

13. The system of claim 11, wherein: The heat exchange device (702) comprises an outer cylinder (7023) and an inner cylinder (7024); the outer cylinder (7023) penetrates the kiln head (7011), the kiln body (7012) and the kiln tail (7013) in sequence along the axis, and one inner cylinder (7024) is inserted into each end of the outer cylinder (7023) and the inserted end of the inner cylinder (7024) extends to the middle part of the lumen of the inner cylinder (7024) along the axis of the outer cylinder (7023); a high-temperature medium inlet (7021) is arranged at each end of the outer cylinder (7023) which is located outside the kiln body (701), a medium backflow port (7025) is arranged at the end of the inner cylinder (7024) which is located inside the outer cylinder (7023), and the inner cylinder (7024) is communicated with the outer cylinder (7023) through the medium backflow port (7025); a low-temperature medium outlet (7022) is arranged on the inner cylinder (7024) which is located outside the outer cylinder (7023).

14. The system of claim 13, wherein: The high-temperature medium inlet (7021) is communicated with the sintering flue.

15. The system of claim 13, wherein: A blind plate (7026) is further arranged in the middle of the barrel cavity of the outer cylinder (7023), and the barrel cavity of the outer cylinder (7023) is divided into two sections of the tube cavity which are not communicated with each other, and the two inner cylinders (7024) are respectively arranged in the two sections of the tube cavity which are not communicated with each other.

16. The system of claim 15, wherein: The kiln body (701) is internally provided with 1-8 heat exchange devices (702) which are uniformly distributed.

17. The system of claim 16, wherein: The gasification device (7) further comprises a water supplement pipeline (7027), the water inlet end of the water supplement pipeline (7027) is communicated with a new water source, the water outlet end of the water supplement pipeline (7027) extends to the inside of the kiln body (7012) after penetrating through the kiln head (7011), and a plurality of atomizing nozzles (7028) are arranged on the water outlet section of the water supplement pipeline (7027).

18. The system of claim 11, wherein: The kiln body (701) is arranged in an inclined manner with the kiln head (7011) being high and the kiln tail (7013) being low.

19. The system of claim 18, wherein: The inclination angle of the kiln body (701) is 2-8°.

20. The system of claim 19, wherein: The inclination angle of the kiln body (701) is 3-6°.

Images