Oil shale high-temperature heat carrier retort furnace

Abstract

The application discloses an oil shale high-temperature heat carrier dry distillation furnace, which comprises a furnace body and a heat exchanger. The furnace body comprises a feeding section, a pre-dry distillation section, a dry distillation section and a decoking section from top to bottom. A gas distributor is arranged in the pre-dry distillation section and the dry distillation section in the furnace chamber of the furnace body. An oil gas collector is arranged at the top of the furnace chamber of the furnace body. The outlet of the oil gas collector is connected with the inlet of the heat exchanger. The air outlet of the heat exchanger is connected with the inlet of the gas distributor arranged in the pre-dry distillation section. The decoking section is provided with a decoking device for decoking the inner surface of the bottom of the furnace body. The bottom of the furnace chamber of the furnace body is provided with a material outlet. The application utilizes the waste heat from the high-temperature oil gas and the shale semi-coke, thereby reducing the heating pressure of the dry distillation section of the furnace chamber, reducing the energy consumption, improving the dry distillation efficiency, increasing the daily processing capacity of a single furnace.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of oil shale development, and particularly relates to an oil shale high-temperature heat carrier dry distillation furnace. BACKGROUND

[0002] As a kind of unconventional energy, oil shale can be decomposed into shale oil, gas and other products by low-temperature dry distillation, and is recognized as the best alternative energy to oil in the world.

[0003] At present, the development and utilization of oil shale in the world is mainly through low-temperature dry distillation. Low-temperature dry distillation is to pass oil shale into a dry distillation furnace under the condition of no oxygen, heat it to pyrolysis temperature by heat carrier, and then produce shale oil, dry distillation gas, solid carbon-containing residue and a small amount of pyrolysis water through pyrolysis reaction.

[0004] The existing dry distillation process has complex structure and high operation cost; the heat utilization of shale semi-coke is low, causing waste of a lot of heat; and the gas distribution of the furnace chamber is uneven, so that the oil shale particles far from the air injection port can only be dry distilled by solid heat transfer, resulting in low dry distillation efficiency and small single furnace processing capacity. SUMMARY

[0005] In order to solve the problems in the prior art, the present application aims to provide an oil shale high-temperature heat carrier dry distillation furnace, which can improve the dry distillation efficiency of oil shale.

[0006] The technical scheme adopted by the present application is as follows:

[0007] The oil shale high-temperature heat carrier dry distillation furnace comprises a furnace body and a heat exchanger, and the furnace body comprises, from top to bottom, a feeding section, a pre-dry distillation section, a dry distillation section and a decoking section; gas distributors are arranged in the pre-dry distillation section and the dry distillation section in the furnace chamber of the furnace body; an oil gas collector is arranged at the top of the furnace chamber of the furnace body; the outlet of the oil gas collector is connected with the inlet of the heat exchanger; and the air outlet of the heat exchanger is connected with the inlet of the gas distributor arranged in the pre-dry distillation section.

[0008] The decoking section is provided with a decoking device for decoking the inner surface of the bottom of the furnace body.

[0009] The bottom of the furnace chamber of the furnace body is provided with a material outlet.

[0010] Preferably, the feeding section comprises a storage bin, a feeding port, an electric turntable and a feeding distributor; the upper end of the feeding port is connected with the storage bin; the lower end of the feeding port is connected with the feeding distributor through the electric turntable; the inlet of the feeding distributor is communicated with the feeding port; the outlet of the feeding distributor extends into the furnace chamber of the furnace body; and the outlet of the feeding distributor is located at the top of the furnace chamber.

[0011] Preferably, the shape of the oil gas collector is umbrella-shaped, the large end of the oil gas collector faces downward, and the oil gas collector is arranged at the central position of the top of the furnace chamber of the furnace body.

[0012] Preferably, the gas distributor comprises a horizontal air inlet pipe, a central air inlet pipe and a plurality of branch air distribution pipes, the central air inlet pipe is coaxially arranged at the center of the hearth of the furnace body, the plurality of branch air distribution pipes are uniformly distributed in the circumferential direction of the central air inlet pipe, each branch air distribution pipe is radially distributed along the central air inlet pipe, one end of the branch air distribution pipe is in communication with the central air inlet pipe, the other end of the branch air distribution pipe is closed, a plurality of air inlets are arranged at intervals in the length direction of the branch air distribution pipe, and the air inlets are arranged downward; one end of the horizontal air inlet pipe is in communication with the central air inlet pipe, and the other end of the horizontal air inlet pipe serves as the inlet of the entire gas distributor.

[0013] Preferably, on each branch air distribution pipe, the plurality of air inlets are distributed from sparse to dense from the inner end to the outer end of the branch air distribution pipe.

[0014] Preferably, the coking device comprises a wall scraper, a wall scraper driving device connected to the wall scraper, the wall scraper is arranged at the bottom of the hearth of the furnace body, the wall scraper driving device is arranged below the furnace body and connected to the wall scraper, and the wall scraper driving device can drive the wall scraper to rotate so as to scrape the inner wall of the bottom of the hearth.

[0015] Preferably, the wall scraper adopts a steel brush structure, comprising a cooling air box and a plurality of steel teeth arranged on the cooling air box, all the steel teeth serving as the bristles of the steel brush structure, the steel teeth adopt a hollow cylindrical structure, one end of the steel teeth is in communication with the cooling air box, and the other end of the steel teeth is used for cleaning the inner wall of the bottom of the hearth of the furnace body, the wall scraper driving device is connected to the cooling air box, and the cooling air box is further connected to a cleaning gas source.

[0016] Preferably, the wall scraper driving device comprises a connecting rod, a base, a wheel rotating bearing and a driver, the wheel rotating bearing is fixedly arranged below the furnace body and coaxially arranged with the hearth of the furnace body, the outer ring of the wheel rotating bearing is fixed on the base, the connecting rod has a gas flow channel inside, the connecting rod comprises a vertical section and a connecting section, the lower end of the vertical section is coaxial and fixedly connected with the inner ring of the wheel rotating bearing, one end of the connecting section is fixedly connected with the upper end of the vertical section, the inner cavities of the vertical section and the connecting section are in communication, the other end of the connecting section is fixedly connected with the cooling air box, and the inner cavity of the connecting section is in communication with the inner cavity of the cooling air box; the output shaft of the driver is connected with the lower end of the vertical section and can drive the vertical section to rotate; the lower end of the vertical section can be rotatably and sealingly connected with the outlet of the cleaning gas source.

[0017] Preferably, the material outlet of the hearth bottom of the furnace body is provided with a slag discharge hopper, the outlet of the slag discharge hopper is below a cooling water tank, the cooling water tank has a partition wall type heat exchanger penetrating through the cooling water tank, the partition wall type heat exchanger is located directly below the outlet of the slag discharge hopper, and the slag discharged from the outlet of the slag discharge hopper can exchange heat with the water in the cooling water tank through the partition wall type heat exchanger; the upper portion of the cooling water tank is provided with a hot air collector, and the outlet of the hot air collector is connected with the inlet of a gas distributor arranged in the pre-dry distillation section.

[0018] The shape of the hot air collector is umbrella-shaped, and the large end of the hot air collector faces downward.

[0019] Preferably, the lower portion of the cooling water tank is provided with a coke conveying belt, and the coke conveying belt is provided with a scraper, which can scrape off the slag adhered to the lower portion of the partition wall type heat exchanger, and the coke conveying belt can convey away the slag falling from the partition wall type heat exchanger and the slag scraped off by the scraper.

[0020] The present application has the following beneficial effects:

[0021] The present application improves the gas distribution mode in the hearth, that is, the gas distributor is arranged in the pre-dry distillation section and the dry distillation section in the hearth, and the oil gas collector is arranged at the top of the hearth of the furnace body, and the waste heat is utilized from the aspects of high-temperature oil gas and shale semi-coke, so that the heat supply pressure of the dry distillation section of the hearth is reduced, the energy consumption is reduced, the dry distillation efficiency is improved, and the daily processing capacity of a single furnace is increased. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a structural schematic view of the oil shale high-temperature heat carrier dry distillation furnace of the present application.

[0023] Figure 2 It is a structural schematic view of the wall scraper of the present application.

[0024] In the figure, 1 is a furnace body, 2 is a feeding section, 21 is a storage bin, 22 is a feeding port, 23 is an electric rotating disc, 24 is a feeding distributor, 25 is a rotating shaft, 3 is a heat exchanger, 31 is an oil gas inlet, 32 is an oil gas outlet, 33 is an air inlet, 34 is an air outlet, 35 is a serpentine heat exchange pipe, 36 is an oil gas collector, 4 is a pre-dry distillation section, 5 is a dry distillation section, 6 is a cooling section, 61 is a slag discharge hopper, 62 is a hot air collector, 63 is a hot air outlet, 64 is a cooling water tank, 65 is an electric rotating wheel, 66 is a coke conveying belt, 67 is a scraper, 7 is a coke removing section, 71 is a wall scraper, 72 is a cooling air tank, 73 is a steel tooth, 75 is a base, 76 is a bearing, 11 is a low-temperature heat carrier inlet, 12 is a branch gas distribution pipe, 13 is an air inlet hole, 14 is a high-temperature heat carrier inlet, 15-1 is a vertical section, and 15-2 is a connecting section. DETAILED DESCRIPTION

[0025] The application will be further described in conjunction with the accompanying drawings and examples.

[0026] As shown in the drawings, Figure 1 The oil shale high-temperature heat carrier dry distillation furnace of the application comprises a furnace body 1 and a heat exchanger 3. The furnace body 1 comprises, from top to bottom, a feeding section 2, a pre-dry distillation section 4, a dry distillation section 5 and a decoking section 7. Gas distributors are arranged in the pre-dry distillation section 4 and the dry distillation section 5 in the hearth of the furnace body 1. An oil gas collector 36 is arranged at the top of the hearth of the furnace body 1. The outlet of the oil gas collector is connected with the inlet of the heat exchanger 3. The air outlet of the heat exchanger 3 is connected with the inlet of the gas distributor arranged in the pre-dry distillation section 4. The gas distributors can make the gas relatively uniformly distributed in the hearth, so that the gas can fully contact with the oil shale particles, thereby facilitating the gas to pass through the oil shale particles and realizing the pyrolysis of the oil shale particles with relatively small diameter. The pre-dry distillation section 4 can preheat the oil shale particles entering the feeding section by using the heat of the oil gas collected by the oil gas collector 36 and the heat recovered from the discharged slag in the cooling section 6, thereby improving the dry distillation efficiency and the heat recovery rate. The decoking section 7 is provided with a decoking device for decoking the inner surface of the bottom of the furnace body 1. The decoking device can clean the coking on the inner surface of the bottom of the furnace body 1, thereby preventing the coking at the bottom of the hearth. The bottom of the hearth of the furnace body 1 is provided with a material outlet, which can discharge the materials after dry distillation and the coking scraped off by the decoking device from the furnace body 1.

[0027] As a feasible scheme of the application, the feeding section 2 comprises a storage bin 21, a feeding port 22, an electric rotating disc 23 and a feeding distributor 24. The upper end of the feeding port 22 is connected with the storage bin 21. The lower end of the feeding port 22 is connected with the feeding distributor 24 through the electric rotating disc 23. The inlet of the feeding distributor 24 is communicated with the feeding port 22. The outlet of the feeding distributor 24 extends into the hearth of the furnace body 1 and is located at the top of the hearth. The oil shale particles are temporarily stored in the storage bin 21 and are distributed to the feeding distributor 24 through the feeding port 22. The outlet branches of the feeding distributor 24 are uniformly rotated by the electric rotating disc 23, so that the oil shale particles are as uniformly as possible arranged in the hearth of the furnace body 1, thereby improving the heat exchange effect of the preheating gas.

[0028] Further improvement of the application is that the shape of the oil gas collector 36 can be umbrella-shaped. The large end of the oil gas collector 36 is downward. The oil gas collector 36 is arranged at the central position of the top of the hearth of the furnace body 1, which is helpful for the recovery of the oil gas and can prevent the accumulation of the oil shale particles.

[0029] As a feasible scheme of the present application, the gas distributor comprises a horizontal gas inlet pipe, a central gas inlet pipe and a plurality of branch gas distribution pipes 12, the central gas inlet pipe is coaxially arranged at the central position of the hearth of the furnace body 1, the plurality of branch gas distribution pipes 12 are uniformly distributed in the circumferential direction of the central gas inlet pipe, each branch gas distribution pipe 12 is radially distributed along the central gas inlet pipe, one end of the branch gas distribution pipe 12 is communicated with the central gas inlet pipe, and the other end of the branch gas distribution pipe 12 is closed, a plurality of gas inlets 13 are arranged at intervals in the length direction of the branch gas distribution pipe 12, and the gas inlets 13 are arranged downward, one end of the horizontal gas inlet pipe is communicated with the central gas inlet pipe, and the other end of the horizontal gas inlet pipe serves as the inlet of the entire gas distributor. The central gas inlet pipe can be supplied with hot gas through the horizontal gas inlet pipe, and each branch gas distribution pipe 12 can be uniformly supplied with gas through the central gas inlet pipe, and the hot gas can be as evenly distributed as possible in the hearth through the plurality of branch gas distribution pipes 12, so that the pyrolysis effect is improved.

[0030] Further improvement of the present application is that, on each branch gas distribution pipe 12, from the inner end (i.e. the end close to the central gas inlet pipe) to the outer end (i.e. the end close to the inner wall of the hearth of the furnace body 1), the plurality of gas inlets 13 are distributed from sparse to dense. This structure design can make the hot gas flow rate of each gas inlet 13 of the branch gas distribution pipe 12 more evenly distributed in the hearth, so as to ensure better contact between the hot carrier and the oil shale particles, and improve the pyrolysis efficiency.

[0031] As a feasible scheme of the present application, the above-mentioned decoking device comprises a wall scraper 71, the wall scraper 71 is connected with a wall scraper driving device, the wall scraper 71 is arranged at the bottom of the hearth of the furnace body 1, the wall scraper driving device is arranged below the furnace body 1 and connected with the wall scraper 71, and the wall scraper driving device can drive the wall scraper 71 to rotate, so as to scrape the inner wall of the bottom of the hearth, which is beneficial to further prevent coking at the bottom of the furnace body 1.

[0032] Further improvement of the present application is that the above-mentioned wall scraper 71 adopts a steel brush structure, which comprises a cooling air box 72 and a plurality of steel teeth 73 arranged on the cooling air box 72, all the steel teeth 73 serve as the bristles of the steel brush structure, the steel tooth 73 adopts a hollow cylindrical structure, one end of the steel tooth 73 is communicated with the cooling air box 72, and the other end of the steel tooth 73 is used for sweeping the inner wall of the bottom of the hearth of the furnace body 1, the wall scraper driving device is connected with the cooling air box 72, and the cooling air box 72 is further connected with a sweeping gas source. The steel tooth 73 adopts a hollow cylindrical structure, which serves as the bristles of the steel brush structure and can sweep the inner wall of the bottom of the hearth of the furnace body 1, the cooling air box 72 can uniformly distribute gas to each steel tooth 73, so that the steel tooth 73 can timely discharge the coking scraped off from the material outlet of the furnace body 1, and the sweeping gas source can supply gas to the cooling air box 72.

[0033] The further improvement of the present application is that the wall scraper driving device comprises a connecting rod, a base 75, a wheel rotating bearing 76 and a driver, the wheel rotating bearing 76 is fixedly arranged below the furnace body 1 and coaxially arranged with the hearth of the furnace body 1, the outer ring of the wheel rotating bearing 76 is fixed on the base 75, the connecting rod has a gas flow channel inside, the connecting rod comprises a vertical section 15-1 and a connecting section 15-2, the lower end of the vertical section 15-1 is coaxially and fixedly connected with the inner ring of the wheel rotating bearing 76, one end of the connecting section 15-2 is fixedly connected with the upper end of the vertical section 15-1, the inner cavities of the vertical section 15-1 and the connecting section 15-2 are communicated, the other end of the connecting section 15-2 is fixedly connected with the cooling air bellow 72, and the inner cavity of the connecting section 15-2 is communicated with the inner cavity of the cooling air bellow 72; the output shaft of the driver is connected with the lower end of the vertical section 15-1 and can drive the vertical section 15-1 to rotate; after the vertical section 15-1 is driven to rotate, the vertical section 15-1 drives the connecting section 15-2 to rotate in the horizontal direction, the connecting section 15-2 can drive the cooling air bellow 72 to rotate in the horizontal direction, so that the whole wall scraper 71 can clean the inner wall surface of the bottom of the hearth, so that the purpose of the wall scraper 71 to scrape the coke on the inner wall of the hearth is realized; the lower port of the vertical section 15-1 can be rotatably and sealingly connected with the outlet of the cleaning gas source, the connection mode can ensure the rotation of the vertical section 15-1 and the air tightness of the connecting part of the vertical section 15-1 and the cleaning gas source. In the above structure, the driver can be any driving device capable of driving the inner ring of the wheel rotating bearing 76 to rotate, such as a motor.

[0034] The further improvement of the present application is that the material outlet of the hearth bottom of the furnace body 1 is provided with a slag discharge hopper 61, the slag discharge hopper can be provided with one or a plurality of small slag discharge hoppers 61, the lower part of each slag discharge hopper 61 is provided with an outlet, the lower part of the outlet of the slag discharge hopper 61 is provided with a cooling water tank 64, the cooling water tank 64 has an inter-wall heat exchanger penetrating through the cooling water tank 64, the cooling water tank 64 and the inter-wall heat exchanger jointly constitute a cooling section, the cooling section can cool and heat the coke and slag discharged from the furnace body 1, the inter-wall heat exchanger is located directly below the outlet of the slag discharge hopper 61, the slag discharged from the outlet of the slag discharge hopper 61 can be heated through the inter-wall heat exchanger and the water in the cooling water tank 64, after the water in the cooling water tank 64 is heated, the air outside the cooling water tank 64 is heated; the upper part of the cooling water tank 64 is provided with a hot air collector 62, the outlet of the hot air collector 62 is connected with the inlet of the gas distributor arranged in the pre-dry distillation section 4, the hot air collector 62 can collect the air heated by the cooling water tank 64 and send the hot air into the pre-dry distillation section 4 to preliminarily heat the oil shale together with the air from the outlet of the heat exchanger 3; the shape of the hot air collector 62 is umbrella-shaped, the large end of the hot air collector 62 is downward, and the hot air is collected.

[0035] In addition, the hot air collected by the hot air collector 62 can be used as the cleaning air source of the cooling air box 72, the hot air collected by the hot air collector 62 can reach above 180℃, and the high-temperature ash can be preliminarily cooled to prevent the ash from being too high in temperature and easily adhering to the side wall and bottom of the furnace body 1, thereby causing difficulty in decoking. In addition, the steel teeth 73 can be heated to prevent the temperature difference between the inner wall and the outer wall of the steel teeth 73 from being too large, thereby damaging the service life of the steel teeth 73.

[0036] Further improvement of the present application is that the ash and coke conveying belt 66 is arranged below the cooling water tank 64, the scraper 67 is arranged on the ash and coke conveying belt 66, the scraper 67 can scrape the ash adhered to the lower part of the partition wall type heat exchanger, and the ash and coke conveying belt 66 can convey away the ash falling from the partition wall type heat exchanger and the ash scraped by the scraper 67.

[0037] Embodiment

[0038] In the oil shale high-temperature heat carrier dry distillation furnace of the embodiment, the furnace body 1 adopts a vertical cylindrical furnace body, and the furnace body 1 is divided into a feeding section 2, a preliminary dry distillation section 4, a dry distillation section 5 and a decoking section 7 from top to bottom. The preliminary dry distillation section 4 and the dry distillation section 5 are each arranged with a gas distributor, and an umbrella-shaped oil gas collector 36 at the top is connected with a heat exchanger 3. The feeding section includes a storage bin 21, a feeding port 22, an electric rotating disc 23 and a feeding distributor 24. The storage bin 21 and the feeding distributor 24 are arranged on the upper side of the hearth, and the feeding distributor adopts a feeding pipeline. In the embodiment, four feeding pipelines are arranged, which are uniformly distributed along the circumference of the furnace body 1. The four feeding pipelines are uniformly distributed at an angle of 90 degrees, and are driven by the electric rotating disc 23 to rotate slowly and uniformly, thereby promoting more uniform feeding distribution. The preliminary dry distillation section 4 is arranged at the top of the hearth, and the hot air conveyed from the heat exchanger and the hot air collector 62 enters the furnace body 1 through the gas distributor to preliminarily heat the oil shale particles. The umbrella-shaped oil gas collector 36 is fixed to the top of the hearth through a connecting rod, and is connected with the heat exchanger 3 through an oil gas inlet 31.

[0039] Specifically, the heat exchanger 3 is connected with the oil gas collector 36 through an oil gas inlet 32 (connected with the hot inlet of the heat exchanger 3) and an oil gas outlet 32 (connected with the hot outlet of the heat exchanger 3) on the outside, and is connected with an air inlet 33 (connected with the cold inlet of the heat exchanger 3) on the upper part and an air outlet 34 (connected with the cold outlet of the heat exchanger 3) on the lower part. The air outlet 34 is connected with an air guide pipe, the other end of the air guide pipe is connected with the air inlet of the gas distributor of the preliminary dry distillation section, and the heat exchanger 3 is internally provided with oil gas serpentine heat exchange pipes 35.

[0040] The dry distillation section 5 is arranged in the middle of the hearth, and the high-temperature heat carrier in the dry distillation section 5 is used to dry distill the oil shale particles preliminarily heated through the gas distributor in the dry distillation section 5. The gas distributor in the dry distillation section 5 is connected with a high-temperature heat carrier inlet 14.

[0041] The gas distributor in the embodiment comprises a horizontal gas inlet pipe, a central gas inlet pipe and six branch gas distribution pipes 12 horizontally distributed at 90 degrees, each of the branch gas distribution pipes 12 has five gas inlets 13 on the lower side, and the gas inlets 13 are arranged from sparse to dense along the radius from the center of the hearth to the outside;

[0042] A wall scraper 71 is arranged in the coking section 7 in the hearth, the wall scraper 71 is connected with a wall scraper driving device, the wall scraper driving device is arranged below the furnace body 1, the wall scraper 71 is arranged at the bottom of the hearth of the furnace body 1, and the bottom of the hearth of the furnace body 1 is provided with a plurality of small slag discharging hoppers 61. The wall scraper 71 adopts a steel brush structure, which specifically comprises a cooling air box 72 and a plurality of steel teeth 73 arranged on the cooling air box 72. All the steel teeth 73 serve as the bristles of the steel brush structure, the steel teeth 73 are in contact with the inner wall of the bottom of the hearth of the furnace body 1, and the steel teeth 73 adopt a hollow cylindrical structure and are in communication with the cooling air box 72. The wall scraper driving device comprises a connecting rod, a rotary bearing 76 and a driver. The connecting rod is a hollow rod, the rotary bearing 76 is fixedly arranged below the furnace body 1 and is coaxially arranged with the hearth of the furnace body 1, and the outer ring of the rotary bearing 76 is fixed. The connecting rod comprises a vertical section and a connecting section. The lower end of the vertical section is coaxial and fixedly connected with the inner ring of the rotary bearing 76, and the lower end of the vertical section serves as a gas inlet. The lower end of the vertical section 15-1 can be rotatably and sealingly connected with the outlet of the cleaning gas source. One end of the connecting section is fixedly connected with the upper end of the vertical section, and the other end of the connecting section is fixedly connected with the cooling air box 72 and in communication with the inner cavity of the cooling air box 72. The driver adopts a motor, the output shaft of which is connected with the inner ring of the rotary bearing 76 and can drive the inner ring of the rotary bearing 76 to rotate.

[0043] The material outlet at the bottom of the hearth of the furnace body 1 is provided with the slag discharging hoppers 61, the slag discharging hoppers adopt a plurality of small slag discharging hoppers 61, each of the slag discharging hoppers 61 is provided with an outlet at the lower part, a cooling water tank 64 is arranged below the outlet of the slag discharging hoppers 61, the cooling water tank 64 has an interval wall type heat exchanger penetrating through the cooling water tank 64, a coke conveying belt 66 is arranged below the cooling water tank 64, a scraper 67 is arranged on the coke conveying belt 66, the hot air collector 62 divides the hot air into two parts through the hot air outlet 63, one part is sent to the pre-dry distillation section 4 to be used together with the hot air output by the heat exchanger 3 to pre-dry the oil shale entering the furnace body 1, and the other part is sent to the cooling air box 72 through the connecting rod and then enters the bottom of the hearth through the hollow cylindrical steel brushes of the cooling air box 72.

[0044] The working principle and process of the oil shale high-temperature heat carrier dry distillation furnace in the embodiment are as follows:

[0045] Oil shale particles from the storage bin 21 through the feed inlet 22, by the feed distributor 24 evenly distributed in the hearth, after the pre-dry distillation section 4, dry distillation section 5, after the discharge of the furnace, by the discharge hopper 61 into the cooling section 6 cooling; high temperature heat carrier is through the high temperature heat carrier inlet 14, center inlet pipe, branch gas distribution pipe, by the air inlet into the dry distillation section 5 of the furnace, with the oil shale particles after the preliminary heating to carry out the heat transfer, so that the oil shale dry distillation decomposition into oil gas products and shale semi coke;

[0046] After the dry distillation of high temperature oil gas produced by the umbrella shaped oil gas collector 36 at the top of the furnace, through the oil gas drainage pipe, through the oil gas inlet 31 into the heat exchanger 3, the air is by the air inlet 33 into the heat exchanger 3, both in the inside and outside of the serpentine heat exchange tube 35 respectively for heat transfer, after the heat exchange of oil gas from the oil gas outlet 32 and collect, air from the air outlet 34, after the guide pipe into the low temperature heat carrier inlet 11 outside the pre dry distillation section, through the gas distributor into the pre dry distillation section 4 of the oil shale particles for preliminary heating; cooling section 6 is through the cooling water tank 64 of the high temperature ash in the discharge hopper 61 cooling, cooling water is evaporated in the heat exchange process into high temperature gas, by the hot air collector 62 of the cooling water tank 64 upper part after the collection, through the hot air outlet 63 discharge, respectively into the pre dry distillation section 4 and the coke removal section 7.

[0047] After the cooling section 6 cooling of ash by the ash coke conveyor belt 66 transmission; wall scraper 71 is located at the bottom of the furnace 1, steel brush close to the lower part of the hearth wall, cooling air tank 72 is connected together by the flange and connecting rod connection section, the vertical section of the connecting rod is fixed on the wheel bearing 76, rely on motor drive wheel bearing 76 and drive the whole steel brush rotation, cleaning the bottom of the hearth ash, promote the coke discharge; wheel bearing 76 is embedded in the center of the hearth base 75.

[0048] 1. Feeding and gas distribution method

[0049] 4 feeding pipe evenly distributed 90 degrees, by the electric turntable driven feeding pipe uniform speed rotation, promote the distribution of feed more uniform, conducive to the follow-up dry distillation;

[0050] Gas distributor in the hearth pre dry distillation section and dry distillation section are arranged one by one, by the horizontal inlet pipe, center inlet pipe and branch gas distribution pipe 12, the center inlet pipe in the circumferential six direction each arrangement one horizontal branch gas distribution pipe 12, each branch gas distribution pipe 12 has 5 gas inlet hole 13 in the lower side, the gas inlet hole 13 is from the center of the hearth to the outside by sparse to dense distribution, because the furnace 1 along the radius outward volume gradually increases, the need for heating of oil shale increases, so the gas inlet hole 13 by sparse to dense distribution is conducive to the uniform heating of particles.

[0051] 2. High temperature oil gas and shale semi coke waste heat utilization

[0052] A heat exchanger 3 is circumscribed outside the top of the furnace, and high-temperature oil gas is collected into the heat exchanger 3 to conduct convective heat exchange with the cold air passing through the heat exchange pipe 29, and the heated cold air is introduced into the pre-dry distillation section 4 to preliminarily heat the particles;

[0053] The cold air is introduced into the air inlet 33 of the heat exchanger 3 to conduct convective heat exchange with the shale semi-coke generated by dry distillation, and the heated cold air is introduced into the pre-dry distillation section 4 by the low-temperature heat carrier inlet 11 to preliminarily dry distill the particles together with the hot air collected by the hot air collector 62.

[0054] In the cooling section 6 below the furnace, the cooling water in the cooling water tank 64 conducts heat exchange with the high-temperature ash in the ash discharge hopper 61 to evaporate and heat the cooling water, and the heated water is used to heat the external air, part of the high-temperature air is used to preliminarily heat the oil shale in the pre-dry distillation section 4, and the other part enters the cooling air tank 72 in the decoking section 7 to enter the bottom of the furnace to preliminarily cool the high-temperature ash, prevent the ash from being sticky due to high temperature, and cause difficulty in decoking, and heat the inner wall of the cylindrical steel brush 73 to prevent the large temperature difference between the inner and outer walls of the steel brush from affecting the service life.

[0055] 3. Remove the ash on the furnace wall

[0056] The wall scraper 71 is arranged at the bottom of the furnace body, and is used to clean the ash on the furnace wall, prevent the ash from accumulating, and promote the ash discharge efficiency.

[0057] 4. Advantages of the present application

[0058] 1. The feeding structure and air distribution structure of the dry distillation furnace are changed, the feeding and heating are more uniform, the dry distillation efficiency of the furnace is improved, and the daily processing capacity of the dry distillation furnace is increased;

[0059] 2. The waste heat is utilized from the high-temperature oil gas and the shale semi-coke, the heat of the pyrolysis products, the high-temperature oil gas and the shale semi-coke, is used to preliminarily dry the oil shale particles, so as to reduce the heating pressure of the dry distillation section of the furnace, and achieve the purpose of reducing energy consumption;

[0060] 3. The wall scraper is arranged at the bottom of the furnace, and the wheel bearing is used to drive the wall scraper to work, remove the ash at the bottom of the furnace, prevent corrosion, and improve the decoking efficiency of the furnace;

[0061] 4. The low-heat of the recovered furnace ash is used to preliminarily cool the high-temperature ash, prevent the ash from sticking on the furnace wall, and heat the inner wall of the steel brush to prevent the large temperature difference between the inner and outer walls of the steel brush from reducing the service life.

Claims

1. A high-temperature heat carrier dry distillation furnace for oil shale, characterized in that, The furnace includes a furnace body (1) and a heat exchanger (3). The furnace body (1) includes a feeding section (2), a pre-drying section (4), a dry distillation section (5) and a decoking section (7) from top to bottom. Gas distributors are provided in both the pre-drying section (4) and the dry distillation section (5) of the furnace body (1). An oil and gas collector (36) is provided at the top of the furnace body (1). The outlet of the oil and gas collector is connected to the inlet of the heat exchanger (3). The air outlet of the heat exchanger (3) is connected to the inlet of the gas distributor provided in the pre-drying section (4). The decoking section (7) is equipped with a decoking device for removing coke from the inner surface of the bottom of the furnace body (1); The bottom of the furnace chamber of the furnace body (1) is provided with a material outlet; The decoking device includes a wall scraper (71), and a wall scraper drive device is connected to the wall scraper (71). The wall scraper (71) is located at the bottom of the furnace chamber of the furnace body (1). The wall scraper drive device is located below the furnace body (1) and connected to the wall scraper (71). The wall scraper drive device can drive the wall scraper (71) to rotate so that the wall scraper (71) can scrape the bottom inner wall of the furnace chamber. The scraper (71) adopts a steel brush structure, including a cooling air box (72) and several steel teeth (73) set on the cooling air box (72). All steel teeth (73) serve as the bristles of the steel brush structure. The steel teeth (73) adopt a hollow cylindrical structure. One end of the steel teeth (73) is connected to the cooling air box (72), and the other end of the steel teeth (73) is used to clean the inner wall of the furnace bottom of the furnace body (1). The scraper drive device is connected to the cooling air box (72).

2. The high-temperature heat carrier dry distillation furnace for oil shale according to claim 1, characterized in that, The feeding section (2) includes a storage bin (21), a feed inlet (22), an electric turntable (23), and a feed distributor (24). The upper end of the feed inlet (22) is connected to the storage bin (21), and the lower end of the feed inlet (22) is connected to the feed distributor (24) through the electric turntable (23). The inlet of the feed distributor (24) is connected to the feed inlet (22), and the outlet of the feed distributor (24) extends into the furnace chamber of the furnace body (1). The outlet of the feed distributor (24) is located at the top of the furnace chamber.

3. The high-temperature heat carrier dry distillation furnace for oil shale according to claim 1, characterized in that, The oil and gas collector (36) is umbrella-shaped with its large end facing downwards. The oil and gas collector (36) is located at the center of the top of the furnace chamber of the furnace body (1).

4. The high-temperature heat carrier dry distillation furnace for oil shale according to claim 1, characterized in that, The gas distributor includes a horizontal inlet pipe, a central inlet pipe, and several branch gas distribution pipes (12). The central inlet pipe is coaxially arranged at the center of the furnace chamber of the furnace body (1). Several branch gas distribution pipes (12) are evenly distributed around the central inlet pipe. Each branch gas distribution pipe (12) is radially distributed along the central inlet pipe. One end of the branch gas distribution pipe (12) is connected to the central inlet pipe, and the other end of the branch gas distribution pipe (12) is closed. Several air inlets (13) are spaced apart along the length of the branch gas distribution pipe (12), and the air inlets (13) face downwards. One end of the horizontal inlet pipe is connected to the central inlet pipe, and the other end of the horizontal inlet pipe serves as the inlet of the entire gas distributor.

5. The high-temperature heat carrier dry distillation furnace for oil shale according to claim 4, characterized in that, On each branched air distribution tube (12), from the inner end to the outer end of the branched air distribution tube (12), several air inlets (13) are distributed from sparse to dense.

6. The high-temperature heat carrier dry distillation furnace for oil shale according to claim 1, characterized in that, The cooling air box (72) is also connected to a purge air source.

7. The high-temperature heat carrier dry distillation furnace for oil shale according to claim 1, characterized in that, The scraper drive device includes a connecting rod, a base (75), a rotary bearing (76), and a driver. The rotary bearing (76) is fixedly installed below the furnace body (1) and coaxially arranged with the furnace chamber of the furnace body (1). The outer ring of the rotary bearing (76) is fixed on the base (75). The connecting rod has a gas flow channel inside. The connecting rod includes a vertical section (15-1) and a connecting section (15-2). The lower end of the vertical section (15-1) is coaxially and fixedly connected with the inner ring of the rotary bearing (76). The connecting section (15-2) One end of the drive is fixedly connected to the upper end of the vertical section (15-1), and the inner cavity of the vertical section (15-1) and the connecting section (15-2) are connected. The other end of the connecting section (15-2) is fixedly connected to the cooling air box (72), and the inner cavity of the connecting section (15-2) is connected to the inner cavity of the cooling air box (72). The output shaft of the drive is connected to the lower end of the vertical section (15-1) and can drive the vertical section (15-1) to rotate. The lower port of the vertical section (15-1) can rotate and be sealed to the outlet of the cleaning air source.

8. The high-temperature heat carrier dry distillation furnace for oil shale according to claim 1, characterized in that, The furnace body (1) has a slag discharge hopper (61) at the bottom of the furnace chamber. A cooling water tank (64) is located below the outlet of the slag discharge hopper (61). The cooling water tank (64) has a wall-type heat exchanger that runs through the cooling water tank (64) from top to bottom. The wall-type heat exchanger is located directly below the outlet of the slag discharge hopper (61). The slag discharged from the outlet of the slag discharge hopper (61) can exchange heat with the water in the cooling water tank (64) through the wall-type heat exchanger. A hot air collector (62) is located above the cooling water tank (64). The outlet of the hot air collector (62) is connected to the inlet of the gas distributor installed in the pre-drying section (4). The hot air collector (62) is umbrella-shaped with its large end facing downwards.

9. The high-temperature heat carrier dry distillation furnace for oil shale according to claim 8, characterized in that, The cooling water tank (64) is provided with a ash and coke conveyor belt (66) below it. The ash and coke conveyor belt (66) is provided with a scraper (67). The scraper (67) can scrape off the slag adhering to the bottom of the partition wall heat exchanger. The ash and coke conveyor belt (66) can transport away the slag falling from the partition wall heat exchanger and the slag scraped off by the scraper (67).

Images