Process and device for preparing powdery upgraded fuel by means of thermal conversion of organic solid waste

Abstract

The present disclosure relates to a process and device for preparing a powdery upgraded fuel by means of thermal conversion of organic solid waste. The thermal conversion comprises two modes, i.e., roasting and pyrolysis. The process for preparing a powdery upgraded fuel by means of thermal conversion of organic solid waste comprises a thermal conversion crushing step, a vibrating thermal conversion screening step, a fluidifying thermal conversion sorting step, and a screw lifting ball-milling thermal conversion step. In the present disclosure, thermal conversion, crushing and separation treatment can be performed on an organic solid waste material at the same time, the thermal conversion process and the crushing and separation process are coupled, coordinated and mutually reinforced, and therefore the thermal conversion reaction rate and conversion efficiency of organic solid waste can be significantly improved, and a powdery thermally-converted upgraded fuel is obtained; when the organic solid waste contains a relatively large amount of metal or non-metal inorganic substances, a variety of sorted products including the metal or non-metal inorganic substances can be recovered at the same time; and particularly, the obtained upgraded fuel is in a powdery state, is suitable for being used as a gasification raw material for a powder boiler and / or an entrained-flow bed, and has good value in terms of resource utilization and high-value utilization.

Description

A process and device for preparing powdered upgraded fuel by thermal conversion of organic solid waste

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application No. 202311497232.8 filed with the Patent Office of China on November 10, 2023, entitled “A process and apparatus for thermal conversion of organic solid waste to prepare powdered upgraded fuel,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to the field of thermal conversion and resource utilization of organic solid waste, and specifically to a process and apparatus for preparing powdered upgraded fuel by thermal conversion of organic solid waste. Background Art

[0004] With the continuous advancement of urbanization and industrialization in my country, a large amount of organic solid waste has been generated in recent years. These mainly include: garbage materials, such as urban organic solid waste, rural organic solid waste, and stale garbage; biomass materials, such as straw, rice straw, fruit shells, peels, and sawdust; sludge materials, such as municipal sludge, printing and dyeing sludge, and oil sludge; and organic polymer materials, such as waste plastics and waste rubber. The clean disposal of organic solid waste has become a huge burden on the sustainable development of human society. Therefore, the development of efficient organic solid waste treatment technologies is of great significance.

[0005] In comparison, garbage materials are the most difficult to handle because their composition is complex and varies depending on the region and source. Their main components may include kitchen waste, paper, plastic products, glass products, metals and other components. Currently, organic solid waste is mainly treated by landfill, anaerobic fermentation, incineration and other methods (such as Chinese patents CN219036642U and CN102897972A). However, the land resources available for landfill are limited, the anaerobic fermentation cycle is long and the efficiency is low, and direct incineration will cause secondary pollution to the environment and produce a large amount of greenhouse gases. In recent years, due to the huge demand for energy, thermochemical conversion and high-value utilization technologies including gasification, baking, pyrolysis and hydrothermal carbonization have received widespread attention.

[0006] Domestic garbage-type organic solid waste is not suitable for direct incineration or direct gasification due to its high moisture content, poor uniformity and low energy density. Usually, the original garbage needs to be dried, crushed and other pre-treatments before it can be incinerated or gasified. Municipal sludge-type organic solid waste also has the problems of high water content and low calorific value. Organic polymer solid wastes such as waste plastics and waste rubber have a low moisture content and high calorific value, but are soft and difficult to crush. The moisture content, calorific value, ash content and crushability of biomass materials are basically in medium condition. The physical properties of different types of organic solid waste vary greatly. During the application process, there may be problems with low calorific value or strong viscosity, which may lead to low conversion efficiency and poor utilization effect. Therefore, it is necessary to bake and / or pyrolyze the organic solid waste to improve the fuel performance of the organic solid waste.

[0007] Baking and pyrolysis are fuel thermal conversion and upgrading technologies under an inert atmosphere. They can significantly improve the fuel properties of organic solid waste, such as increasing energy density, grindability and uniformity. In subsequent combustion or gasification reactions, they can effectively improve the combustion stability of the fuel, or enhance the refrigerant gas efficiency (CGE) and syngas quality of the gasification reaction.

[0008] However, existing baking and pyrolysis technologies still face the following major problems. First, compared with gasification and combustion, the operating temperature of baking or pyrolysis treatment is lower, resulting in slower surface temperature rise of the material, while the volume of unbroken materials is larger, and the internal temperature rises even slower, especially the surface products that have been converted are attached to the outside of the material. At the same time, the porous product layer structure leads to a low thermal conductivity of the surface products, which further limits the transfer of heat to the interior of the material, which is not conducive to the internal temperature rise of the material, resulting in poor thermal conversion effect, low production efficiency, and long operation time. Second, the composition and volume distribution of organic solid waste are uneven. At a certain temperature, it may be the case that small particles of easily reacting materials have been completely converted, while large volumes of difficult-to-react materials have not yet fully reacted, resulting in low baking or pyrolysis efficiency.

[0009] In view of this, the present disclosure proposes a technical solution that can achieve thermal conversion, crushing and separation at the same time, that is, the thermal conversion and crushing and separation processes are coupled and coordinated, and reinforced each other. The porous product shell formed on the surface of the material can be quickly peeled off during the thermal conversion and crushing process, and the inside of the material is exposed to the thermal conversion temperature, which significantly improves the thermal conversion reaction rate and conversion efficiency of organic solid waste, and can simultaneously recover a variety of sorting products in addition to the thermal conversion upgraded fuel. In particular, the obtained upgraded fuel has a powdery state and is suitable for use as a raw material for powder boilers and / or fluidized bed gasification, and has outstanding resource and high-value utilization value.

[0010] Summary of the Invention

[0011] To achieve the above objectives, the present disclosure adopts the following technical solutions:

[0012] Unless otherwise specified, the contents described in this disclosure refer to mass contents; the operating temperatures described in this disclosure refer to the temperatures at which solid materials are discharged from a device.

[0013] The present disclosure first provides an apparatus for producing powdered upgraded fuel by thermal conversion of organic solid waste. The apparatus comprises three main line units, namely, a thermal conversion and crushing unit, a vibration thermal conversion and screening unit, and a fluidized thermal conversion and sorting unit, which are connected in sequence. Each of the three main line units is equipped with a corresponding gas heat carrier. For ease of distinction, the gas heat carrier equipped with the thermal conversion and crushing unit is referred to as the first gas heat carrier, the gas heat carrier equipped with the vibration thermal conversion and screening unit is referred to as the second gas heat carrier, and the gas heat carrier equipped with the fluidized thermal conversion and sorting unit is referred to as the third gas heat carrier. The first, second, and third gas heat carriers are respectively used to thermally convert the organic solid waste passing through the three main line units and / or to entrain fuel particles stripped from the surface of the organic solid waste. The apparatus also includes a gas-solid separation unit for receiving the gas heat carriers entrained with fuel particles discharged from the three main line units and separating the fuel particles from the gas heat carriers. A ball mill thermal conversion unit is also included.

[0014] Preferably, the gas heat carrier carrying fuel particles discharged from each unit of the three main line units is respectively connected to an independent gas-solid separation unit; the particle outlets of each gas-solid separation unit are commonly connected to a spiral ball mill heat conversion unit; and the spiral ball mill heat conversion unit is equipped with a fourth gas heat carrier.

[0015] The thermal conversion and crushing unit is used to perform a simultaneous thermal conversion process on organic solid waste materials while crushing them, wherein the thermal conversion process at least includes flowing a first gaseous heat carrier downstream over the surface of the organic solid waste materials to be crushed. The crushing process is achieved by shearing and / or hammering the organic solid waste materials to be crushed through the thermal conversion and crushing unit using a crushing unit provided within the unit.

[0016] The vibrating thermal conversion screening unit is connected to the material outlet of the thermal conversion crushing unit. It is used to perform preliminary screening of the crushed material and continue the thermal conversion process during the screening process. Specifically, the thermal conversion screening unit includes two layers of inclined screen plates and an inclined bottom plate, and the lowest side of each of the three is provided with a material discharge channel. The material intercepted by the upper screen plate returns to the thermal conversion crushing unit to continue the thermal conversion and crushing process; the material intercepted by the lower screen plate is sent to the ball mill thermal conversion unit or the fluidized bed thermal conversion unit. The material received by the bottom plate is transported to the gas-solid separation device via a gas conveying mechanism.

[0017] The fluidized thermal conversion and sorting unit includes a fluidized bed, which is connected to the outlet of the lower sieve plate of the vibrating screening thermal conversion device and is used to perform fluidized thermal conversion and sorting treatment on the particulate matter; a third gas heat carrier is introduced from the air distribution plate of the fluidized bed as a fluidizing gas, and mechanical vibration is combined to promote the fluidization of the particles, thereby achieving fluidized thermal conversion and sorting treatment of the particulate matter; wherein, fine fuel particles enter the gas-solid separation unit with the fluidizing gas; inorganic particles are discharged from the overflow port of the fluidized bed as boiling bed material; metals and some large particles cannot be fluidized and are collected as bottom slag at the bottom of the fluidized bed, and then, under the action of mechanical vibration, they enter the screw airflow bidirectional conveying mechanism along the inclined plate at the bottom of the fluidized bed. Another third gas heat carrier is introduced into the screw airflow bidirectional conveying mechanism to purge the particulate matter, and the fuel particles with lower density are blown up and returned to the fluidized bed along the return path, while the metals with higher density are retained in the screw airflow bidirectional conveying mechanism and are conveyed and discharged by the screw, thereby achieving the separation of fuel particles, inorganic particles and metal particles while thermally converting.

[0018] The ball milling thermal conversion unit is connected to the particle outlet of each gas-solid separation unit and the lower sieve plate outlet of the vibration screening thermal conversion unit, and is used to perform ball milling thermal conversion treatment on the input particles and produce powdered upgraded fuel.

[0019] The present disclosure also provides a process for producing powdered upgraded fuel by thermal conversion of organic solid waste, which is performed using the apparatus described above. Specifically, the process includes sequential or intermittent thermal conversion crushing steps, vibration thermal conversion screening steps, and fluidized thermal conversion sorting steps; it also includes a ball milling thermal conversion step, wherein:

[0020] The operating temperature of the thermal conversion crushing step is 180-550°C. The material to be crushed is subjected to a thermal conversion treatment while being crushed by providing a first gas heat carrier to the material to be crushed. The first gas heat carrier comprises at least a purge gas flowing downstream from the surface of the material to be crushed. The purge gas provides the material to be crushed with heat required for thermal conversion and carries away moisture generated by volatilization and thermal decomposition as well as fine fuel particles peeled off from the surface of the organic solid waste. The large-particle solid phase material obtained by crushing is fed into the vibration thermal conversion screening unit through the material outlet.

[0021] The operating temperature of the vibration heat conversion screening step is 180-550°C, and the operating temperature here is maintained within the above operating temperature range by introducing a second gas heat carrier into the shell interlayer of the screening heat conversion reactor.

[0022] The solid material from the thermal conversion crushing unit first enters the upper large-hole sieve plate and moves downward under the action of mechanical vibration and gravity. Thermal conversion reaction continuously occurs during the downward movement. The surface products are continuously peeled off under the action of mechanical vibration and particle friction, producing powdered thermal conversion quality-enhancing fuel. Smaller particles fall into the lower small-hole vibrating sieve plate, and powdered materials with even smaller particle sizes fall to the bottom of the reactor and are received by the bottom plate.

[0023] Among them, the upper layer product returns to the thermal conversion crushing unit; the bottom plate material is sent to the gas-solid separation unit through the air flow conveying mechanism; the lower sieve plate material enters the downstream fluidized thermal conversion sorting unit (when garbage is used as raw material) or the ball mill thermal conversion unit (other organic solid waste).

[0024] The operating temperature of the fluidized thermal conversion and sorting step is 300-600° C., and is used to perform fluidized thermal conversion and sorting treatment on the materials obtained by vibration thermal conversion screening.

[0025] The operating temperature of the ball milling thermal conversion step is 300-600° C., and is used to perform a grinding thermal conversion treatment on the solid material obtained from the lower sieve plate of the gas-solid separation unit and / or the vibration thermal conversion screening unit.

[0026] The organic solid waste described in the present disclosure includes: garbage materials, such as urban organic solid waste, rural organic solid waste, and stale garbage; biomass materials, such as straw, rice straw, fruit shells, fruit peels, and wood chips; sludge materials, such as municipal sludge, printing and dyeing sludge, and oil sludge; and organic polymer materials, such as waste plastics and waste rubber.

[0027] Preferably, when the organic solid waste is biomass, sludge, or organic polymer, the materials are sequentially processed through a thermal conversion crushing unit, a vibration thermal conversion screening unit, and a ball mill thermal conversion unit; and when garbage is processed, the materials are sequentially processed through a thermal conversion crushing unit, a vibration thermal conversion screening unit, a fluidized thermal conversion sorting unit, and a ball mill thermal conversion unit, wherein the fluidized thermal conversion sorting unit is mainly used for the sorting and recovery of metal and non-metallic inorganic substances.

[0028] To save space, the specific structure, operation mode and specific details of each operation step of the above-mentioned units will be explained in the specific implementation method part and will not be described in detail here.

[0029] Compared with the prior art, the present disclosure can at least achieve the following beneficial effects: a thermal conversion crushing unit is used to realize the simultaneous crushing and thermal conversion treatment of organic solid waste, wherein the thermal conversion process can quickly form a brittle product shell at the new section formed by crushing, thereby reducing the viscosity of the material. At the same time, the crushing process can continuously crush the product shell on the surface of the material, so that the interior of the organic solid waste material is exposed to the thermal conversion atmosphere, thereby removing the product shell on the surface of the material from hindering the heat transfer to the interior of the material; that is, in the thermal conversion crushing step of the present disclosure, the thermal conversion process and the crushing process can promote each other, and objectively achieve better thermal conversion and crushing effects, and can make the dried and thermally converted materials directly crushed without cooling, thereby greatly reducing heat loss; the coaxial counter-rotating crushing part is used to realize efficient crushing of the material, which can effectively avoid the technical problem of large pieces of material entering the fluidized bed due to insufficient crushing, thereby blocking the fluidizing gas channel; by rationally regulating the fluidization conditions, fluidized screening of metal blocks and non-metallic inorganic substances contained in the material particles can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] FIG1 is a schematic flow diagram of the process disclosed herein;

[0031] Figure 2 is a schematic diagram of a thermal conversion crushing device;

[0032] FIG3 is a schematic diagram of a crushing part fixedly connected to a short shaft via a fixed disk;

[0033] Figure 4 is a schematic diagram of the crushing part being driven and connected to the short shaft via a planetary gear set;

[0034] Figure 5 is a schematic diagram of a screening thermal conversion reactor;

[0035] Figure 6 is a schematic diagram of a fluidized bed;

[0036] FIG7 is a schematic diagram of a ball mill heat conversion unit;

[0037] FIG8 is an AA view in FIG7;

[0038] FIG9 is a top view of FIG7;

[0039] Figure 10 is a schematic diagram of the screw.

[0040] In the figure, 1 is a heat conversion crushing unit, 2 is a crushing cylinder, 3 is an outer cylinder, 4 is an insulation layer, 5 is a material inlet, 6 is a material outlet, 7 is a purge gas inlet, 8 is a purge gas outlet, 9 is a motor, 10 is a drum gear, 11 is a support leg, 12 is a short shaft, 13 is a reversing bevel gear set, 14 is a shear knife set, 15 is a rotary hammer set, 16 is a chain ball set, 17 is a fixed plate, 18 is a central gear, 19 is a transmission gear, 20 is a ring gear, 21 is a screening heat conversion reactor, 22 is a heat conversion inner cavity, 23 is an interlayer, 24 is an upper sieve plate, 25 is a lower sieve plate, 26 is a bottom plate, 27 is an upper screening discharge port, 28 is a lower screening discharge port, 29 is a bottom plate screening discharge port, 30 is a vibration component, 31 is a screening feed port, 32 is a second air filter. The heat carrier inlet is 33, the second gas heat carrier outlet 33, 34 is the fluidized bed, 35 is the air distribution plate, 36 is the inclined plate, 37 is the fluidized bed feed port, 38 is the fluidizing gas outlet, 39 is the overflow port, 40 is the partition, 41 is the return path, 42 is the screw airflow bidirectional conveying mechanism, 43 is the grinding box, 44 is the hollow wall, 45 is the lifting screw, 46 is the heat storage grinding ball, 47 is the screw feeder, 48 is the overflow outlet, 49 is the fourth gas heat carrier inlet, 50 is the fourth gas heat carrier outlet, 51 is the worm, 52 is the gear, 53 is the inner and outer double-layer gas jacket, 54 is the product gas outlet, 55 is the rotary joint inlet, 56 is the rotary joint outlet, 57 is the dual-channel rotary joint, 58 is the conveying gas inlet, and 59 is the valve. DETAILED DESCRIPTION

[0041] Example 1

[0042] This embodiment provides an apparatus for preparing powdered upgraded fuel by thermal conversion of organic solid waste, as shown in FIG1 , comprising a thermal conversion crushing unit 1, a vibration thermal conversion screening unit, and a fluidized thermal conversion sorting unit connected in sequence; the thermal conversion crushing unit is equipped with a first gas heat carrier, the vibration thermal conversion screening unit is equipped with a second gas heat carrier, and the fluidized thermal conversion sorting unit is equipped with a third gas heat carrier; and further comprising a gas-solid separation unit for receiving the gas heat carrier containing fuel particles discharged from the three main line units and separating the fuel particles from the gas heat carrier.

[0043] The particle outlet of the gas-solid separation unit is connected to the ball mill heat conversion unit; the ball mill heat conversion unit is equipped with a fourth gas heat carrier.

[0044] As shown in Figures 2-4, the thermal conversion crushing unit 1 includes an outer cylinder 3 and a crushing cylinder 2. The bottom of the outer cylinder 3 is supported and fixed by legs 10. The crushing cylinder 2 is rotatably mounted in the outer cylinder 3, and the left and right ends of the crushing cylinder 2 extend beyond the outer cylinder 3 and are rotatably sealed with the outer cylinder 3. A heating jacket is formed between the inner and outer cylinders. The first gas heat carrier is divided into two streams. One stream is used as a simple heating gas to enter the heating jacket to heat the wall of the crushing cylinder 2; the other stream is used as a purge gas to enter the inner cavity of the crushing cylinder 2 and flow downstream from the surface of the material to be crushed. The outer side of the outer cylinder 3 is provided with an insulation layer 4.

[0045] A pair of supporting wheels are respectively provided at the bottom of both ends of the crushing drum 2 beyond the outer cylinder 3, and the supporting wheels are used to provide rolling support for the crushing drum 2; a roller gear 10 is also provided on the outer surface of one end of the crushing drum 2, and the roller gear 10 cooperates with the driving device to drive the crushing drum 2 to rotate.

[0046] The crushing drum 2 is provided with a feed cap and a discharge cap at each end, respectively. Both the feed cap and the discharge cap are sealed against the crushing drum 2 and do not rotate with the crushing drum 2. The feed cap is provided with a material inlet 5 for introducing organic solid waste into the crushing drum 2, and a purge gas inlet 7. The bottom of the discharge cap is provided with a material outlet 6 for discharging the material after thermal conversion and crushing. The top of the discharge cap is provided with a purge gas outlet 8; the purge gas outlet 8 is connected to the gas-solid separation device.

[0047] The crushing drum 2 is internally equipped with a crushing assembly comprising a bidirectional rotating shaft and a crushing unit mounted thereon. The crushing unit comprises a shearing blade assembly 14, a rotary hammer assembly 15, and / or a chain ball assembly 16. The bidirectional rotating shaft comprises multiple short shafts 12 and a reversing bevel gear assembly 13. The reversing bevel gear assembly 13, through three sequentially meshing bevel gears, causes two adjacent short shafts 12 to rotate in opposite directions. Each short shaft 12 is provided with a crushing unit, thereby causing the crushing units on adjacent short shafts 12 to rotate in opposite directions. One end of at least one short shaft 12 extends beyond the feed end cap or the discharge end cap of the crushing drum 2 and is connected to a driving component.

[0048] In order to further improve the crushing effect, each short shaft 12 of the present invention is provided with multiple crushing parts, and the multiple crushing parts on the same short shaft 12 have two opposite rotation directions. Specifically, a part of the multiple crushing parts on the same short shaft 12 is fixedly sleeved on the short shaft 12 by a fixed disk 17 or directly fixedly connected to the short shaft 12, thereby having the same first rotation direction as the rotating shaft; the remaining crushing parts are rotationally connected to the short shaft 12 through a planetary gear assembly, thereby having a second rotation direction opposite to that of the short shaft 12. The planetary gear assembly includes a central gear 18 fixedly sleeved on the short shaft 12, a transmission gear 19 meshing with the central gear 18, a ring gear 20 meshing with the transmission gear 19, and a frame (not shown in the figure) for fixing and / or supporting the central gear 18, the transmission gear 19 and the ring gear 20; the remaining crushing parts are fixed to the outer peripheral wall of the ring gear 20, thereby having a second rotation direction opposite to that of the short shaft 12.

[0049] Preferably, the crushing parts with opposite rotation directions on the same short shaft 12 are arranged at intervals from each other.

[0050] The crushing drum 2 is tilted to utilize its own gravity to convey the crushed material toward the material outlet 6. Alternatively, a conveying component is provided within the crushing drum 2. This conveying component can be a conveyor belt located below the crushing drum 2, with both ends secured within the inlet and outlet caps. Alternatively, the conveying component can be a spiral blade secured to the inner wall of the crushing drum 2. When the crushing drum 2 rotates, the spiral blade propels the material toward the material outlet 6.

[0051] As shown in Figure 5, the vibration heat conversion screening unit includes a screening heat conversion reactor 21 with several vibration components 30 at the bottom. The screening heat conversion reactor 21 includes a heat conversion cavity 22, an interlayer 23 wrapping the heat conversion cavity 22, and an upper sieve plate 24 and a lower sieve plate 25 inclined in the heat conversion cavity 22. The heat conversion cavity 22 has an inclined bottom plate 26; a second gas heat carrier inlet 32 ​​and a second gas heat carrier outlet 33 are respectively provided on opposite sides of the interlayer 23. The aperture of the upper sieve plate 24 is larger than that of the lower sieve plate 25, so that the material is gradient screened; a screening feed port 31 connected to the material outlet 6 is provided at the top of the heat conversion inner cavity 22 corresponding to the higher side of the upper sieve plate 24; the upper sieve plate 24, the lower sieve plate 25 and the bottom plate 26 are respectively connected to the upper screening discharge port 27, the lower screening discharge port 28 and the bottom plate screening discharge port 29 on their lower sides; each screening discharge port is placed side by side and is respectively connected to an inverted trapezoidal tank body, the inverted trapezoidal tank body Valves are installed at the constricted openings of the tank body, respectively used to discharge solid material from the surfaces of the upper sieve plate 24, lower sieve plate 25, and bottom plate 26. A conveying gas inlet 58 is provided outside the valve 59 on the inverted trapezoidal tank body of the bottom plate screening outlet 29. This conveying gas inlet 58 is connected to a second gas heat carrier, which is introduced as a conveying gas to blow the fine particles discharged from the bottom plate 26 into the gas-solid separation unit. Screw conveyors are installed outside the inverted trapezoidal tank body valves of the screening outlets of the upper and lower sieve plates. The upper screening outlet 27 is connected to the material inlet 5 of the thermal conversion crushing device; the lower screening outlet 28 is connected to the fluidized bed feed port 37 and the ball mill thermal conversion unit screw feeder 47 via two valved pipes.

[0052] Preferably, both the upper and lower sieve plates have square sieve holes. The square hole size of the upper sieve plate 24 is 5mm*5mm, the square hole size of the lower sieve plate 25 is 1mm*1mm, and the bottom plate 26 is a smooth metal plate with a complete surface and no holes.

[0053] Preferably, the upper and lower sieve plates and the bottom plate 26 are all at an angle of 5 to 10 degrees to the horizontal plane.

[0054] Preferably, the horizontal cross-section of the vibration heat conversion screening device is a rectangle, and its aspect ratio is 5:1 to 10:1; the vibration component 30 can adopt a conventional vibration form in the field, for example, it is composed of a plurality of spring legs arranged at the bottom of the screening device and a plurality of symmetrically arranged eccentric motors.

[0055] As shown in Figure 6, the fluidized heat conversion and separation unit includes a fluidized bed 34, which has a grid-shaped air distribution plate 35 formed by a grid of gas pipelines arranged horizontally and vertically, and the air distribution plate 35 is placed horizontally; a wind hood is provided at the intersection of the gas pipelines, and a third gas heat carrier is introduced into the fluidized bed 34 through the air distribution plate 35 to serve as fluidizing gas; the gap size formed by the crossed gas pipelines is 15 to 20 mm.

[0056] Preferably, the bottom surface of the space below the air distribution plate 35 is an inclined plate 36 fixedly connected to the main body of the fluidized bed 34, and the angle between the inclined plate 36 and the horizontal plane is 5 to 10 degrees. The vibration component 30 arranged at the four bottom corners of the fluidized bed 34 applies vibration to the fluidized bed 34.

[0057] A screw airflow bidirectional conveying mechanism 42 is provided on one side of the lowest position of the inclined plate 36 and is connected to the material on the upper surface of the inclined plate 36; a partition plate 40 is provided above the screw airflow bidirectional conveying mechanism 42, and the partition plate 40 constructs a return path 41 in the fluidized bed 34 that is connected to the upper part of its gas phase space; a gap is left between the bottom of the partition plate 40 and the inclined plate 36, and the gap forms a channel for the bottom material to enter the screw airflow bidirectional conveying mechanism 42.

[0058] The screw airflow bidirectional conveying mechanism 42 includes a horizontal conveying screw, the lower part of which is provided with a gas distributor arranged along the axial direction of the conveying screw. The gas distributor is connected to a third gas heat carrier as back-blowing gas, which blows the light and small materials in the screw away from the screw and returns them to the upper space of the fluidized bed 34 through the aforementioned return path 41. The larger and heavier materials in the screw airflow bidirectional conveying mechanism 42 are discharged from one end thereof under the pushing action of the screw.

[0059] The fluidized bed feed port 37 is connected to the lower screening discharge port 28 of the vibration heat conversion screening unit; an overflow port 39 is provided in the middle and upper part of the fluidized bed 34, and a fluidizing gas outlet 38 is provided at the top.

[0060] Preferably, the horizontal cross-section of the fluidized bed 34 is rectangular, with an aspect ratio of 8:1 to 12:1, wherein the overflow port 39 is provided in the middle portion along the length direction of the fluidized bed 34 .

[0061] As shown in Figures 7-10, the ball mill heat conversion unit includes a grinding box 43 with a hollow wall 44. The inner cavity of the grinding box 43 is a quality-improving and powder-making area, and is provided with at least one lifting screw 45 and filled with graded heat-storage grinding balls 46; a fourth gas heat carrier inlet 49 is provided at the bottom of the hollow wall 44, and a fourth gas heat carrier outlet 50 is provided at the top; a screw feeder 47 is connected to the bottom of one side of the grinding box 43; an overflow outlet 48 is provided at the upper part of the other side of the grinding box 43 opposite to the screw feeder 47; a power assembly for driving the lifting screw 45 to rotate is provided at the upper part of the grinding box 43; the power assembly includes a motor 9, a reducer, a worm 51 connected to the reducer, and a gear 52 provided at the top of the lifting screw 45 and cooperating with the worm 51.

[0062] The lifting screw 45 has a double-layer hollow structure, forming an inner and outer double-layer gas jacket 53. A double-channel rotary joint 57 is installed at the bottom of the lifting screw 45. The rotary joint air inlet 55 is connected to the lower end of the outer gas jacket; the rotary joint air outlet 56 is connected to the lower end of the inner gas jacket; the rotary joint air inlet 55 is connected to the fourth gas heat carrier, and the fourth gas heat carrier first ascends along the outer gas jacket in the screw, reaches the top, and then descends along the inner jacket and is discharged.

[0063] The outer wall of each lifting screw 45 includes a first spiral blade and a second spiral blade.

[0064] The outer wall of the grinding box 43 is provided with a heat-insulating material. The grinding box 43 is also provided with a product gas outlet 54 , which is also used as a ball loading port.

[0065] The heat storage grinding balls are metal balls with graded diameters of 10 mm, 30 mm, and 60 mm, and the number of metal balls of each size is the same;

[0066] The outer diameter of the screw is in the range of 300 to 500 mm; the pitch of the screw is 0.5 to 0.7 times the outer diameter of the screw.

[0067] Example 2

[0068] As shown in Figure 1, this embodiment provides a process for preparing powdered upgraded fuel by thermal conversion of organic solid waste, which is performed using the apparatus described in Example 1. Specifically, the process includes the following steps:

[0069] S1, thermal conversion crushing step, by supplying a first gas heat carrier to the heating jacket and the purge gas inlet 7, the operating temperature of the thermal conversion crushing step is maintained at 180-550°C; wherein the purge gas flows downstream from the surface of the material to be crushed and is discharged from the purge gas outlet 8; the purge gas provides the heat required for thermal conversion to the material to be crushed, and entrains the moisture generated by the volatilization and thermal decomposition of the material and the fine fuel particles peeled off from the surface of the material. The fuel particles enter the gas-solid separation unit with the purge gas, and the separated solid material is sent to the ball mill thermal conversion unit, and the resulting gas phase flow is passed to the gas-liquid separation and upgrading purification unit; under the purge gas atmosphere, the material to be crushed is crushed by several crushing units, and the large solid phase material obtained by crushing is sent to the vibration thermal conversion screening unit through the material outlet 6. The first gas heat carrier includes pyrolysis gas and / or gasification gas and / or flue gas with an oxygen volume content of no more than 1%.

[0070] S2, a vibration thermal conversion screening step, in which a second gas heat carrier is introduced into the interlayer 23 to maintain the operating temperature of the screening thermal conversion reactor 21 at 180-550°C; under vibration conditions, the two sieve plates in the screening thermal conversion reactor 21 perform thermal conversion screening on the solid material from the thermal conversion crushing unit. The solid material first contacts the upper sieve plate 24 and moves downward under the action of mechanical vibration and gravity. During the downward movement, thermal conversion reaction continuously occurs, and the surface products are continuously peeled off under the action of mechanical vibration and particle friction to produce powdered thermal conversion quality-enhanced fuel. At the same time, large particle materials continue to become smaller. During the movement, smaller particles continuously fall into the lower sieve plate 25. The powdered material with smaller particle size on the lower sieve plate 25 falls to the bottom of the reactor and is received by the bottom plate 26, forming three streams of upper, middle and lower materials moving downward along the inclined surface.

[0071] The product particles from the upper sieve plate 24 are the largest and are returned to the thermal conversion and crushing unit. The material intercepted by the bottom plate 26 has the smallest particle size and is sent to the gas-solid separation unit via the airflow conveying mechanism. The material intercepted by the lower sieve plate 25 enters the downstream fluidized thermal conversion and sorting unit (when using garbage as the raw material) or the ball mill thermal conversion unit (for other organic solid waste). The second gaseous heat carrier includes pyrolysis gas, gasification gas, and flue gas with an oxygen content of no more than 1%.

[0072] S3, fluidized thermal conversion and sorting step, the operating temperature of the fluidized bed 34 is maintained at 300-600°C by supplying a third gas heat carrier to the air distribution plate 35, and the third gas heat carrier also serves as a fluidizing gas; the inorganic particles in the material discharged from the lower sieve plate 25 form a grinding bed material in the fluidized bed 34, and the density of the grinding bed material is less than that of metal aluminum but greater than that of fine organic matter and fine fuel particles; by adjusting the supply amount and gas velocity of the third gas heat carrier, the grinding bed material is made to be in a boiling fluidized state in the fluidized bed 34, and the fluidization effect of uneven particles is improved by mechanical vibration; the powdered thermal conversion quality-enhancing fuel enters the gas phase with the fluidizing gas and goes to the gas-solid separation unit; the solid material obtained in the gas-solid separation unit is sent to the ball mill thermal conversion unit; the boiling bed material in the fluidized bed 34 is discharged through the overflow port 39 system, the content of non-metallic inorganic matter with glass slag and sand as the main components in this part of the material is not less than 95% (only for garbage materials); the heavy components and some large-particle organic matter in the fluidized bed 34 are in a non-fluidized state and deposited at the bottom of the bed to form a bottom material, and the bottom material enters the screw airflow bidirectional conveying mechanism 42 under the action of mechanical vibration; the light material in the bottom material is backblown back to the gas phase space of the fluidized bed 34 in the screw airflow bidirectional conveying mechanism 42, wherein the large-particle organic matter that has not fully reacted is settled again and fully contacts with the gas heat carrier and the grinding bed material, continues to be converted and continuously crushed to obtain a powdered thermal conversion quality-improving fuel; the heavy material in the bottom material that is not blown back to the fluidized bed 34 is discharged from the system through the screw airflow bidirectional conveying mechanism 42, and the metal content of this part of the bottom material is not less than 90% (only for garbage materials).

[0073] The third gas heat carrier includes pyrolysis gas and / or gasification gas and / or flue gas with an oxygen volume content not exceeding 0.5%.

[0074] S4, the ball milling thermal conversion step, maintains the operating temperature of the ball milling thermal conversion step at 300-600°C by supplying a fourth gas heat carrier to the hollow structure of the hollow wall 44 and the lifting screw 45, thereby grinding and thermally converting the upgraded fuel obtained from the gas-solid separation unit and / or the vibration thermal conversion screening unit. The material to be ground enters the ball milling thermal conversion unit through a screw feeder 47. Heat from the screw, spiral blades, and the outer wall of the heat storage spheres and the inner wall of the grinding chamber further heats the material to be ground. Simultaneously, the rotation of the screw drives the heat storage grinding balls and the upgraded fuel to circulate from bottom to top and from inside to outside. Under the extrusion, shearing, and friction of the heat storage balls and spiral blades, the material to be ground continuously peels off and pulverizes, exposing the internal material and rapidly converting it. The small particles of material obtained by grinding overflow from outlet 48 to form powdered upgraded fuel. Large particles gradually shrink through this repetitive upward and downward cycle, ultimately being completely converted into powdered upgraded fuel.

[0075] The feed particle size of the ball mill thermal conversion unit does not exceed 5 mm. The particle size of the obtained powdered upgraded fuel does not exceed 0.09 mm.

[0076] The organic solid waste described in the present disclosure includes: garbage materials, such as urban organic solid waste, rural organic solid waste, and stale garbage; biomass materials, such as straw, rice straw, fruit shells, fruit peels, and wood chips; sludge materials, such as municipal sludge, printing and dyeing sludge, and oil sludge; and organic polymer materials, such as waste plastics and waste rubber.

[0077] Preferably, when the organic solid waste is biomass, sludge, or organic polymer, the material is sequentially processed through a thermal conversion crushing unit, a vibration thermal conversion screening unit, and a ball mill thermal conversion unit, i.e., a three-step process; and when garbage is processed, the material is sequentially processed through a thermal conversion crushing unit, a vibration thermal conversion screening unit, a fluidized thermal conversion sorting unit, and a ball mill thermal conversion unit, i.e., a four-step process, wherein the fluidized thermal conversion sorting unit is mainly used for metal sorting and recovery. The three-step process and the four-step process can be switched by adjusting the valves of the two valved pipes connected to the lower screening outlet. When the lower screening outlet is connected to the ball mill thermal conversion unit, the three-step process is executed, and the fluidized thermal conversion sorting unit is idle; when the lower screening outlet is connected to the fluidized thermal conversion sorting unit, the four-step process is executed.

[0078] Application Example 1

[0079] Raw materials: virgin domestic waste, initial moisture content 53%, feed rate 2000kg / h, feed temperature 30℃.

[0080] Process type: Four-step process.

[0081] Processing flow: The raw material is fed into a thermal conversion and crushing device with a discharge temperature of 230°C. The first gas heat carrier used in this device is hot flue gas with an oxygen content of 1%. After treatment, the gaseous phase flows into a gas-solid separation device. The solid material obtained by gas-solid separation is passed to a ball mill thermal conversion unit, and the remaining gaseous phase flows to a gas-liquid separation and purification unit. The large solid phase material obtained by crushing is fed through the material outlet to a vibration thermal conversion and screening device. The solid material from the thermal conversion and crushing device enters a vibration thermal conversion and screening device with a discharge temperature of 230°C. After vibration thermal conversion and screening by two layers of sieve plates, the large-particle material intercepted by the upper sieve plate 24 returns to the thermal conversion and crushing unit. The smallest particle size material is received by the bottom plate 26 and is swept into the gas-solid separation device by a second gas heat carrier in the airflow conveying mechanism. The second gas heat carrier is flue gas with an oxygen content of no more than 1%. The gaseous phase flow obtained by gas-solid separation enters a gas-liquid separation and purification unit, and the remaining solid material passes to the ball mill thermal conversion unit. The material intercepted by the lower sieve plate 25 is sent to a fluidized bed thermal conversion and sorting unit. The solid material from the lower sieve plate 25 enters the fluidized thermal conversion and sorting device with a discharge temperature of 600°C. The third gas heat carrier (fluidizing gas) used in this device is hot flue gas with an oxygen content of 0.5%. After treatment, the fluidizing gas carries the fuel particles into the gas-solid separation device. The gas phase flow obtained by gas-solid separation is passed into the gas-liquid separation and quality improvement purification unit, and the obtained solid material is passed into the ball mill thermal conversion unit; the boiling fluidized bed material is discharged from the overflow port and collected for use; the non-fluidized bottom slag is discharged through the screw airflow bidirectional conveying mechanism at the bottom of the fluidized bed 34 and collected for use. The solid-phase material from the gas-solid separation device corresponding to the three units of thermal conversion crushing, vibration thermal conversion screening, and fluidized thermal conversion sorting is passed into a ball mill thermal conversion device with a discharge temperature of 600°C. A fourth gas heat carrier, hot flue gas with an oxygen content of 0.5%, is introduced into the interior of the lifting screw and the hollow wall of the grinding box. The material in the grinding box undergoes further thermal conversion reaction and crushing and pulverization under the heating and extrusion action of the screw, spiral blades, outer wall of the heat storage sphere, and inner wall of the grinding box. The resulting powdered upgraded fuel is discharged from the overflow outlet and collected for future use.

[0082] Process effect: Through the treatment, a total of powdered thermal conversion upgraded fuel was obtained, with an overall mass yield of 43% relative to the dry raw material, a particle size range of less than 0.09 mm, and a calorific value of 23.9 MJ / kg; the mass yield of the non-fluidized bottom slag recovered by the fluidized thermal conversion sorting device was 7%, with a particle size range of 1 mm to 5 mm, of which the metal content was 92%; the solid material yield obtained from the overflow port of the fluidized thermal conversion sorting device was 17%, with a particle size range of 0.5 mm to 2 mm, of which the non-metallic inorganic content was 98%.

[0083] Application Example 2

[0084] Raw materials: waste plastics, initial moisture content 5%, feed rate 1100 kg / h, feed temperature 30°C.

[0085] Process type: three-step process.

[0086] Processing process: The raw materials are sent to the thermal conversion crushing device with a discharge temperature of 550°C. The first gas heat carrier used in the device is the pyrolysis gas obtained by pyrolysis conversion of the upgraded fuel. The gaseous phase flow after treatment enters the gas-solid separation device, and the solid material obtained by gas-solid separation is passed into the ball mill thermal conversion unit. The obtained gaseous phase flow is passed into the gas-liquid separation and upgrading purification unit; the large-particle solid phase material is sent to the vibration thermal conversion screening device through the lower discharge port at the rear end. The solid material from the thermal conversion crushing device enters the vibration thermal conversion screening device with a discharge temperature of 550°C. After the vibration thermal conversion screening process of the two layers of sieve plates, the large-particle material intercepted by the upper sieve plate 24 returns to the thermal conversion crushing unit; the smallest-particle material is received by the bottom plate 26 and enters the air flow conveying mechanism. Under the purge action of the second gas heat carrier, it enters the gas-solid separation device. The second gas heat carrier is the pyrolysis gas obtained by pyrolysis conversion of the upgraded fuel. The gas phase flow obtained by gas-solid separation enters the gas-liquid separation and upgrading purification unit, and the obtained solid material is passed into the ball mill thermal conversion unit; the material intercepted by the lower sieve plate 25 is also passed into the ball mill thermal conversion device. The solid-phase material from the gas-solid separation device of the thermal conversion crushing and vibration thermal conversion screening unit, as well as the material intercepted by the lower sieve plate 25 of the vibration thermal conversion screening unit, are passed into a screw-elevating ball mill thermal conversion device with a discharge temperature of 550°C. A fourth gas heat carrier is introduced into the interior of the elevating screw 45 and the hollow wall 44 of the grinding box. The fourth gas heat carrier is pyrolysis gas obtained by pyrolysis conversion of the upgraded fuel. Under the heating and extrusion action of the elevating screw 44, spiral blades, outer wall of the heat storage sphere and inner wall of the grinding box, the material in the reactor further undergoes thermal conversion reaction and is crushed and pulverized. The obtained powdered upgraded fuel is discharged from the overflow outlet 48 and collected for future use.

[0087] Process effect: Through the treatment, a total of powdered thermal conversion quality-enhancing fuel was obtained, with an overall mass yield of 52% relative to the dry basis raw materials, a particle size range of less than 0.07mm, and a calorific value of 31.5MJ / kg.

[0088] Application Example 3

[0089] Raw materials: municipal sludge, initial moisture content 65%, feed rate 2200 kg / h, feed temperature 30℃.

[0090] Process type: three-step process.

[0091] The process flow is as follows: the raw materials are fed into a thermal conversion and crushing unit with a discharge temperature of 180°C. The first gas heat carrier used in this unit is hot flue gas with an oxygen content of 1%. After treatment, the gaseous phase flows into a gas-solid separation unit. The solid material obtained from the gas-solid separation is passed to a ball mill thermal conversion unit, and the gaseous phase flows into a gas-liquid separation and purification unit. Large solid particles are fed into a vibration thermal conversion and screening unit through the rear lower discharge port. The solid material from the thermal conversion and crushing unit enters a vibration thermal conversion and screening unit with a discharge temperature of 300°C. After vibration thermal conversion and screening on two sieve plates, the large-particle material on the upper layer returns to the thermal conversion and crushing unit. The smallest particle size material on the bottom plate enters the air conveying mechanism and enters the gas-solid separation unit under the purge of the second gas heat carrier, which is hot flue gas with an oxygen content of 0.5%. The gaseous phase flow obtained from the gas-solid separation enters a gas-liquid separation and purification unit, and the solid material is passed to the ball mill thermal conversion unit. The material on the lower sieve plate also passes into the screw-elevated ball mill thermal conversion unit. The solid phase material from the gas-solid separation device of the thermal conversion crushing and vibration thermal conversion screening unit, as well as the material on the lower sieve plate of the vibration thermal conversion screening unit, are passed into a screw-elevating ball mill thermal conversion device with a discharge temperature of 500°C. A fourth gas heat carrier is introduced into the interior of the screw and the hollow wall 44 of the grinding box. The fourth gas heat carrier is hot flue gas with an oxygen content of 0.5%. Under the heating and extrusion action of the screw, spiral blades, outer wall of the heat storage sphere and inner wall of the grinding box, the material in the reactor further undergoes thermal conversion reaction and is crushed and pulverized. The resulting powdered upgraded fuel is discharged from the overflow outlet 48 and collected for use.

[0092] Through the processing, a total of powdered thermal conversion upgraded fuel was obtained, with an overall mass yield of 68% relative to the dry basis raw materials, a particle size range of less than 0.06mm, and a calorific value of 17.2MJ / kg.

[0093] Application Example 4

[0094] Raw materials: bales of corn stalks, initial moisture content 10%, feed rate 1200 kg / h, feed temperature 30°C.

[0095] Process type: three-step process.

[0096] Processing process: The raw materials are fed into a thermal conversion and crushing device with a discharge temperature of 180°C. The first gas heat carrier used in this device is the gasified gas obtained by gasification of the upgraded fuel. After treatment, the gaseous phase flows into the gas-solid separation device. The solid material obtained by gas-solid separation is passed to the ball mill thermal conversion unit, and the gaseous phase flows into the gas-liquid separation and upgrading purification unit. Large solid particles are fed into the vibration thermal conversion screening device through the rear lower discharge port. The solid material from the thermal conversion and crushing device enters the vibration thermal conversion screening device with a discharge temperature of 300°C. After vibration thermal conversion and screening by two layers of sieve plates, the large particles intercepted by the upper sieve plate 24 are returned to the thermal conversion and crushing unit. The smallest particles on the bottom plate enter the air flow conveying mechanism and enter the gas-solid separation device under the purge of the second gas heat carrier. The second gas heat carrier is the gasified gas obtained by gasification of the upgraded fuel. The gaseous phase flow obtained by gas-solid separation enters the gas-liquid separation and upgrading purification unit, and the solid materials are passed to the ball mill thermal conversion unit. The material on the lower sieve plate is also passed into the ball mill thermal conversion unit. The solid-phase material from the gas-solid separation device of the thermal conversion crushing and vibration thermal conversion screening unit, as well as the solid-phase material from the lower sieve plate of the vibration thermal conversion screening unit, is introduced into a ball mill thermal conversion device with a discharge temperature of 300°C. A fourth gas heat carrier, which is the gasified gas obtained by gasifying the upgraded fuel, is introduced into the interior of the lifting screw 45 and the hollow wall 44 of the grinding box. Under the heating and extrusion action of the screw, spiral blades, the outer wall of the heat storage sphere, and the inner wall of the grinding box, the material in the reactor undergoes further thermal conversion reaction and is crushed and pulverized. The resulting powdered upgraded fuel is discharged from the overflow outlet 48 and collected for future use.

[0097] Process effect: Through the treatment, a total of powdered thermal conversion upgraded fuel was obtained, with an overall mass yield of 82% relative to the dry basis raw materials, a particle size range of less than 0.08 mm, and a calorific value of 22.5 MJ / kg.

[0098] Application Example 5

[0099] Raw materials: bales of wheat straw, initial moisture content 8%, feed rate 1300 kg / h, feed temperature 30°C.

[0100] Process type: three-step process.

[0101] Processing process: The raw materials are fed into a thermal conversion and crushing device with a discharge temperature of 180°C. The first gas heat carrier used in this device is hot flue gas with an oxygen content of 1%. After treatment, the gaseous phase flows into a gas-solid separation device. The solid material obtained from the gas-solid separation is passed into a ball mill thermal conversion unit, and the gaseous phase flows into a gas-liquid separation and purification unit. Large solid particles are fed into a vibration thermal conversion screening device through the rear lower discharge port. The solid material from the thermal conversion and crushing device enters a vibration thermal conversion screening device with a discharge temperature of 300°C. After vibration thermal conversion and screening by two layers of sieve plates, the large particles intercepted by the upper sieve plate 24 are returned to the thermal conversion and crushing unit. The smallest particles on the bottom plate enter the air conveying mechanism and enter the gas-solid separation device under the purge of the second gas heat carrier, which is hot flue gas with an oxygen content of 1%. The gaseous phase flow obtained from the gas-solid separation enters a gas-liquid separation and purification unit, and the solid materials are passed into the ball mill thermal conversion unit. The material on the lower sieve plate is also passed into the screw-elevated ball mill thermal conversion unit. The solid-phase material from the gas-solid separation device of the thermal conversion crushing and vibration thermal conversion screening unit, as well as the solid-phase material from the lower sieve plate of the vibration thermal conversion screening unit, is passed into a screw-elevating ball mill thermal conversion device with a discharge temperature of 450°C; a fourth gas heat carrier, hot flue gas with an oxygen content of 0.5%, is introduced into the interior of the elevating screw 45 and the hollow wall 44 of the grinding box. Under the heating and extrusion action of the screw, spiral blades, the outer wall of the heat storage sphere, and the inner wall of the grinding box, the material in the reactor further undergoes a thermal conversion reaction and is crushed and pulverized. The resulting powdered upgraded fuel is discharged from the overflow outlet 48 and collected for later use.

[0102] Process effect: Through the treatment, a total of powdered thermal conversion upgraded fuel was obtained, with an overall mass yield of 48% relative to the dry basis raw materials, a particle size range of less than 0.06mm, and a calorific value of 24.8MJ / kg.

[0103] It should be pointed out that the above embodiments are only specific implementation examples of the technical solutions of the present disclosure, rather than limitations of the technical solutions of the present disclosure. The scope of protection of the present disclosure shall be subject to the limitations of the claims. Industrial Applicability

[0104] The process and apparatus for preparing powdered quality-enhanced fuel by thermal conversion of organic solid waste provided by the present disclosure adopts a thermal conversion crushing unit to realize the crushing and thermal conversion treatment of organic solid waste, significantly improving the reaction rate and conversion efficiency of thermal conversion of organic solid waste, wherein the thermal conversion process and the crushing process can promote each other, and the dried and thermally converted materials are directly crushed without cooling, which greatly reduces heat loss and improves production efficiency; the crushing part with coaxial counter-rotation realizes efficient crushing of materials, effectively avoiding the technical problem of large pieces of materials entering the fluidized bed and blocking the fluidizing gas channel due to insufficient crushing. At the same time, the process and apparatus for preparing powdered quality-enhanced fuel by thermal conversion of organic solid waste provided by the present disclosure realizes fluidized screening of metal blocks and non-metallic inorganic substances contained in the material particles by rationally regulating the fluidization conditions during the treatment process, and recovers a variety of sorting products other than thermal conversion quality-enhanced fuel, especially the obtained quality-enhanced fuel has a powdery state, is suitable for use as a raw material for powder boiler and / or fluidized bed gasification, and has outstanding resource utilization and high value.

Claims

1. A device for preparing powdered fuel by thermal conversion of organic solid waste, comprising a thermal conversion crushing unit (1), a vibration thermal conversion screening unit and a fluidized thermal conversion sorting unit connected in sequence; characterized in that: It also includes a gas-solid separation unit and a ball mill heat conversion unit; the heat conversion crushing unit (1) includes a rotatably arranged crushing cylinder (2), a crushing assembly is arranged in the crushing cylinder (2), and the crushing cylinder (2) is connected to a first gas heat carrier as a purge gas; the vibration heat conversion screening unit includes an upper sieve plate (24), a lower sieve plate (25) and a bottom plate (26) arranged obliquely, wherein the material intercepted by the upper sieve plate (24) returns to the vibration heat conversion screening unit; the material intercepted by the lower sieve plate (25) is connected to the fluidized heat conversion sorting unit and the ball mill heat conversion unit respectively through two valved pipelines; the material received by the bottom plate (26) is transported by air flow The mechanism is connected to a gas-solid separation unit, and the gas flow conveying mechanism is connected to a second gas heat carrier as a conveying gas; the fluidized heat conversion separation unit includes a fluidized bed (34), which has a grid-shaped air distribution plate (35) composed of crossed gas pipelines, and a wind cap is provided at the intersection of the gas pipelines; the air distribution plate (35) is connected to a third gas heat carrier as a fluidizing gas; the gas-solid separation unit is used to receive purge gas, conveying gas and fluidizing gas, and separate the entrained fuel particles from the gas; the particle outlet of the gas-solid separation unit is connected to a ball mill heat conversion unit; the ball mill heat conversion unit is connected to a fourth gas heat carrier as a heating medium.

2. The device for preparing powdered upgraded fuel by thermal conversion of organic solid waste according to claim 1, characterized in that: The thermal conversion crushing unit further comprises a fixedly arranged outer cylinder (3), the crushing cylinder (2) is rotatably sleeved in the outer cylinder (3), and both ends extend beyond the outer cylinder (3) and are rotatably sealed with the outer cylinder (3), and a heating jacket is formed between the inner and outer cylinders; the first gas heat carrier is divided into two streams, one of which enters the heating jacket as a pure heating gas; and the other stream is passed into the inner cavity of the crushing cylinder (2) as a purge gas and flows downstream from the surface of the material to be crushed.

3. The device for preparing powdered upgraded fuel by thermal conversion of organic solid waste as claimed in claim 2, characterized in that: The two ends of the crushing barrel (2) are respectively provided with a feed end cap and a discharge end cap, and the feed end cap and the discharge end cap are both sealed with the crushing barrel (2) for rotation and do not rotate with the crushing barrel (2); the feed end cap is provided with a material inlet (5) and a purge gas inlet (7); the bottom of the discharge end cap is provided with a material outlet (6), and the top is provided with a purge gas outlet (8).

4. The device for preparing powdered upgraded fuel by thermal conversion of organic solid waste according to claim 1, characterized in that: The crushing assembly comprises a bidirectional rotating shaft and a crushing part arranged on the bidirectional rotating shaft, wherein the crushing part comprises a shearing knife group (14) and / or a rotating hammer group (15) and / or a chain ball group (16); the bidirectional rotating shaft is composed of a plurality of short shafts (12) and a reversing bevel gear group (13), and two adjacent short shafts (12) rotate in opposite directions.

5. The device for preparing powdered upgraded fuel by thermal conversion of organic solid waste as claimed in claim 4, characterized in that: Each short shaft (12) is provided with a plurality of crushing parts, and the plurality of crushing parts on the same short shaft (12) have two opposite rotation directions.

6. The device for preparing powdered upgraded fuel by thermal conversion of organic solid waste according to claim 1, characterized in that: The vibration heat conversion screening unit comprises a screening heat conversion reactor (21) with a plurality of vibration components (30) arranged at the bottom, the screening heat conversion reactor (21) comprising a heat conversion inner cavity (22) and an interlayer (23) wrapping the heat conversion inner cavity (22); the heat conversion inner cavity (22) comprises a bottom plate, and an upper sieve plate (24) and a lower sieve plate (25) are arranged inside; a second gas heat carrier inlet (32) and a second gas heat carrier outlet (33) are respectively arranged on opposite sides of the interlayer (23); the aperture of the upper sieve plate (24) is larger than that of the lower sieve plate (25); and a screening feed port (31) is arranged above the higher side of the upper sieve plate (24).

7. The device for preparing powdered upgraded fuel by thermal conversion of organic solid waste according to claim 6, characterized in that: The upper and lower sieve plates both have square sieve holes, and the bottom plate (26) is a smooth metal plate with a complete surface and no holes; the upper and lower sieve plates and the bottom plate (26) are at an angle of 5 to 10° with the horizontal plane; the horizontal cross-section of the vibration heat conversion screening device is a rectangle, and its length-to-width ratio is 5:1 to 10:

1.

8. The device for preparing powdered upgraded fuel by thermal conversion of organic solid waste according to claim 1, characterized in that: The bottom surface of the space below the air distribution plate (35) is an inclined plate (36) fixedly connected to the main body of the fluidized bed (34); a screw airflow bidirectional conveying mechanism (42) connected to the material on the upper surface of the inclined plate (36) is provided on one side at the lowest position of the inclined plate (36).

9. The device for preparing powdered upgraded fuel by thermal conversion of organic solid waste as claimed in claim 8, characterized in that: The screw airflow bidirectional conveying mechanism (42) comprises a conveying screw, a gas distributor arranged along the axial direction of the conveying screw is provided at the lower part thereof, the gas distributor is connected to a third gas heat carrier as back-blowing gas, and the organic particles entering the screw airflow bidirectional conveying mechanism (42) are back-blown back to the gas phase space of the fluidized bed (34) through the gas distributor, and the airflow is blown upward, and the larger and heavier materials are discharged under the action of the conveying screw; an overflow port (39) is provided in the middle and upper part of the fluidized bed (34), and a fluidizing gas outlet (38) is provided at the top.

10. The device for preparing powdered upgraded fuel by thermal conversion of organic solid waste according to claim 9, characterized in that: A partition (40) is provided above the screw airflow bidirectional conveying mechanism (42), and the partition (40) constructs a return path (41) in the fluidized bed (34) that is connected to the upper part of its gas phase space; a gap is left between the bottom of the partition (40) and the inclined plate (36), and the gap forms a channel for the bottom material to enter the screw airflow bidirectional conveying mechanism (42).

11. The device for preparing powdered upgraded fuel by thermal conversion of organic solid waste according to claim 9, characterized in that: The angle between the inclined plate (36) and the horizontal plane is 5 to 10 degrees. Vibration components (30) are provided at the four bottom corners of the fluidized bed (34). The horizontal cross-section of the fluidized bed (34) is rectangular, and the length-to-width ratio is 8:1 to 12:

1. The overflow port (39) is provided in the middle of the length direction of the fluidized bed (34).

12. The device for preparing powdered upgraded fuel by thermal conversion of organic solid waste according to claim 1, characterized in that: The ball mill heat conversion unit comprises a grinding box (43) with a hollow wall (44); the inner cavity of the grinding box (43) is provided with at least one lifting screw (45) and is filled with graded heat storage grinding balls (46); the hollow wall (44) is provided with a fourth gas heat carrier inlet (49) and a fourth gas heat carrier outlet (50); an overflow outlet (48) is provided at the upper part of the grinding box (43); and a power component for driving the lifting screw (45) to rotate is also included.

13. The device for preparing powdered upgraded fuel by thermal conversion of organic solid waste according to claim 12, characterized in that: The lifting screw (45) is a double-layer hollow structure, forming an inner and outer double-layer gas jacket (53). A double-channel rotary joint (57) is installed at the bottom of the lifting screw (45). The rotary joint air inlet (55) is connected to the lower end of the outer gas jacket; the rotary joint air outlet (56) is connected to the lower end of the inner gas jacket; the rotary joint air inlet (55) is connected to the fourth gas heat carrier, and the fourth gas heat carrier first ascends along the outer gas jacket in the lifting screw (45), and then descends along the inner gas jacket after reaching the top and is discharged; the outer wall of each lifting screw (45) includes a first spiral blade and a second spiral blade.

14. A process for preparing powdered upgraded fuel by thermal conversion of organic solid waste, characterized in that: The steps include: S1, thermal conversion crushing step, the material to be crushed enters the thermal conversion crushing unit, and is subjected to crushing and thermal conversion treatment at an operating temperature of 180-550°C; the crushing and thermal conversion treatment at least includes mechanical crushing of the material to be crushed and allowing the purge gas to flow downstream from the surface of the material to be crushed, and the purge gas provides the material to be crushed with heat required for thermal conversion; the purge gas discharged from the thermal conversion crushing unit enters the gas-solid separation unit; the solid material obtained by crushing is sent to the vibration thermal conversion screening unit; S2, vibration thermal conversion screening step, the solid material obtained by crushing enters the vibration thermal conversion screening unit, and is subjected to vibration thermal conversion and gradient screening treatment at an operating temperature of 180-550°C through two layers of inclined sieve plates; the vibration thermal conversion screening unit has an inclined bottom plate; wherein the material particle size intercepted by the upper sieve plate (24) is the largest, and is returned to the thermal conversion crushing unit; the material particle size received by the bottom plate (26) is the smallest, and is sent to the air-solid separation unit through the air flow conveying mechanism; the lower sieve plate (25) intercepts the material particle size of the solid material. The material is sent to the fluidized thermal conversion crushing unit, and step S3 is executed at this time; or sent to the ball mill thermal conversion unit, and step S3 is not executed at this time; S3, fluidized thermal conversion sorting step, the material intercepted by the lower sieve plate (25) enters the fluidized bed (34) of the fluidized thermal conversion sorting unit, and is subjected to fluidized thermal conversion sorting treatment at an operating temperature of 300-600°C; the fluidized bed (34) has an air distribution plate (35) composed of crossed gas pipelines, and a hood for gas outlet is provided at the intersection of the gas pipelines; the inorganic particles contained in the material form a grinding bed material in the fluidized bed (34); the supply amount and gas velocity of the fluidizing gas are adjusted so that the grinding bed material is in a boiling fluidized state in the fluidized bed (34), promoting the thermal conversion product layer to be peeled off from the surface of the material particles to form an upgraded fuel; the fluidization effect of the uneven particles is improved by mechanical vibration; the fluidized gas entrains the upgraded fuel particles to the gas-solid separation unit; the boiling bed material is discharged from the overflow port (39); the metal particles fall from the gap of the air distribution plate (35) to the inclined plate (36) at the bottom of the fluidized bed (34) and are then discharged; S4, ball milling thermal conversion step, the material enters the ball milling thermal conversion unit, and is subjected to ball milling and thermal conversion treatment at an operating temperature of 300-600°C to obtain a powdered upgraded fuel; The solid materials obtained through gas-solid separation in each step are sent to the ball mill thermal conversion unit.

15. The process for preparing powdered upgraded fuel by thermal conversion of organic solid waste according to claim 14, characterized in that: The organic solid waste includes: urban domestic waste, rural domestic waste, stale waste, straw, rice straw, fruit shells, fruit peels, wood chips, municipal sludge, printing and dyeing sludge, oil sludge, waste plastics, and waste rubber; wherein, when the organic solid waste is one or more of urban domestic waste, rural domestic waste, and stale waste, the material intercepted by the lower sieve plate (25) enters the fluidized bed (34), and step S3 is performed; when the organic solid waste does not include any one of urban domestic waste, rural domestic waste, and stale waste, the material intercepted by the lower sieve plate (25) enters the ball mill thermal conversion unit, and step S3 is not performed.

16. The process for preparing powdered upgraded fuel by thermal conversion of organic solid waste according to claim 15, characterized in that: In step S1, the operating temperature of the thermal conversion and crushing step is controlled by supplying a first gas heat carrier to the thermal conversion and crushing unit, wherein the first gas heat carrier is also used as a purge gas; the first gas heat carrier includes pyrolysis gas and / or gasification gas and / or flue gas with an oxygen volume content not exceeding 1%; In step S2, a second gas heat carrier is introduced into the vibration heat conversion screening unit to maintain the operating temperature of the vibration heat conversion screening step, and the second gas heat carrier is also used as a conveying gas of the air flow conveying mechanism; the second gas heat carrier includes pyrolysis gas, gasification gas, and flue gas with an oxygen content not exceeding 1%; In step S3, a third gas heat carrier is supplied to the air distribution plate (35) to maintain the operating temperature of the fluidized bed (34), and the third gas heat carrier serves as fluidizing gas; the third gas heat carrier comprises pyrolysis gas and / or gasification gas and / or flue gas with an oxygen volume content not exceeding 0.5%; a screw airflow bidirectional conveying mechanism (42) connected to the upper surface of the inclined plate (36) is provided at the bottom of the fluidized bed (34); the third gas heat carrier is also used as back-blowing gas of the screw airflow bidirectional conveying mechanism (42), and organic particles entering the screw airflow bidirectional conveying mechanism (42) are back-blown back to the gas phase space of the fluidized bed (34), and heavy materials that are not blown back are discharged through the screw airflow bidirectional conveying mechanism (42), and the metal content of this part of heavy materials is not less than 90%; In step S4, the operating temperature of the ball milling heat conversion is maintained by supplying a fourth gas heat carrier to the ball milling heat conversion unit; the feed particle size of the ball milling heat conversion unit does not exceed 5 mm; the particle size of the obtained powdered upgraded fuel does not exceed 0.09 mm; and the powdered upgraded fuel obtained by grinding is discharged from the overflow outlet (48).

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