A system and process for extracting and reusing gasification slag

Abstract

The present application provides a gasification slag extraction and recycling system and process to solve the problems of complex process, low recovery rate, high cost, and failure to achieve ideal utilization value, and inability to effectively improve the comprehensive utilization efficiency of gasification slag. The system includes a clean water pool, a gasification slag stirring pool, a first vibrating screen, a first sorting machine group, a second sorting machine group, and a second filter press; the discharge port of the gasification slag stirring pool is connected with the feed port of the first vibrating screen; the under-screen discharge port of the first vibrating screen is connected with the feed port of the first sorting machine group; the coarse concentrate discharge port of the first sorting machine group is connected with the feed port of the second sorting machine group; the concentrate discharge port of the second sorting machine group is connected with the second filter press. Glass crystals, tailing coarse particles, high-ash, fine tailings, fixed carbon, high-heat quality coal, and fine coal products are obtained by separating and extracting from the gasification slag using the system, which can be directly sold or recycled through a recycling production line.

Description

Technical Field

[0001] This invention relates to the comprehensive utilization technology of coal chemical gasification slag, specifically to a gasification slag extraction and reuse system and process. Background Technology

[0002] Currently, in the field of coal gasification slag treatment, vibrating screen dewatering and filter press dewatering technologies are often used in combination to treat coarse and fine slag in the residue. However, using high-frequency vibrating screens and centrifuges alone for dewatering results in low comprehensive utilization rate and high energy consumption. For example, in the field of coal slime treatment, most of the ash separation is achieved by using flotation columns, frothers, and kerosene. This process is complex, requires large investment, consumes a lot of energy, has high operating costs, and has a low recovery rate. It does not achieve the maximum utilization value of resources and cannot effectively improve the comprehensive utilization efficiency of gasification slag.

[0003] Therefore, it is essential to develop comprehensive utilization methods for coal chemical gasification slag that are simple in process and low in cost. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of existing coal gasification slag treatment processes being complex, having low recovery rates, high costs, failing to achieve ideal utilization value, and not effectively improving the comprehensive utilization efficiency of gasification slag. In response, this invention provides a gasification slag extraction and reuse system and process.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A gasification slag extraction and reuse system is characterized by comprising a clear water tank, a gasification slag mixing tank, a first vibrating screen, a first sorting unit, a second sorting unit, and a second filter press.

[0007] The clear water tank is used to supply water to the system;

[0008] The outlet of the gasification slag mixing tank is connected to the inlet of the first vibrating screen;

[0009] The undersize discharge port of the first vibrating screen is connected to the feed port of the first sorting unit;

[0010] The coarse concentrate outlet of the first sorting unit is connected to the feed inlet of the second sorting unit;

[0011] The concentrate outlet of the second sorting unit is connected to the second filter press.

[0012] Furthermore, it includes a third sorting unit, a third vibrating screen, and a fourth vibrating screen;

[0013] The concentrate outlet of the second sorting unit is connected to the feed inlet of the third sorting unit;

[0014] The fixed carbon outlet of the third sorting unit is connected to the feed inlet of the third vibrating screen;

[0015] The high-calorific-quality coal outlet of the third sorting unit is connected to the feed inlet of the fourth vibrating screen;

[0016] The undersize discharge ports of the third and fourth vibrating screens are both connected to the second filter press.

[0017] Furthermore, this includes desliming screens;

[0018] The discharge port of the first vibrating screen is connected to the feed port of the desliming screen, and the discharge port of the desliming screen is connected to the fine slag tank.

[0019] The water screened out by the desliming screen enters the thickening tank or fine tailings pond through a gravity pipe or a slurry pump.

[0020] Furthermore, it includes a feeding hopper, a fine slag pool, a glass crystal silo, a coarse concentrate pool, a second vibrating screen, a fine tailings pool, a first filter press, a concentrate pool, a high ash pool, a first slurry pump, a second slurry pump, a fixed carbon silo, a high calorific value coal silo, a clean coal pool, a clean coal silo, a tailings silo, a dryer, a recycling production line, and a coarse tailings silo.

[0021] The discharge port of the feeding hopper is connected to the inlet of the gasification slag mixing tank;

[0022] The undersize discharge port of the first vibrating screen is connected to the fine slag tank, and the oversize discharge port is connected to the glass crystal chamber.

[0023] The underflow outlet of the fine slag tank is connected to the feed inlet of the first sorting unit;

[0024] The coarse concentrate outlet of the first sorting unit is connected to the coarse concentrate pool, and the coarse tailings outlet of the first sorting unit is connected to the feed inlet of the second vibrating screen.

[0025] The upper discharge port of the second vibrating screen is connected to the feed port of the coarse tailings bin, and the lower discharge port of the second vibrating screen is connected to the fine tailings pool.

[0026] The bottom outlet of the rough concentrate pool is connected to the feed inlet of the second separator unit;

[0027] The concentrate outlet of the second sorting unit is connected to the feed inlet of the concentrate pool, and the high ash outlet of the second sorting unit is connected to the high ash pool or the fine tailings pool.

[0028] The bottom outlet of the fine tailings pond is connected to the feed inlet of the first filter press; the discharge outlet of the first filter press is connected to the feed inlet of the tailings bin; and the discharge outlet of the tailings bin is connected to the recycling production line.

[0029] The bottom outlet of the concentrate pool is connected to the feed inlet of the third separator unit;

[0030] The fixed carbon outlet of the third sorting unit is connected to the inlet of the first slurry pump, the outlet of the first slurry pump is connected to the inlet of the third vibrating screen, and the on-screen outlet of the third vibrating screen is connected to the fixed carbon bin.

[0031] The high-calorific-quality coal outlet of the third sorting unit is connected to the inlet of the second slurry pump, the outlet of the second slurry pump is connected to the inlet of the fourth vibrating screen, and the on-screen outlet of the fourth vibrating screen is connected to the high-calorific-quality coal bin.

[0032] The under-screen discharge ports of the third and fourth vibrating screens are both connected to the feed inlet of the clean coal pool.

[0033] The bottom outlet of the refined coal pool is connected to the second filter press. After being dewatered by the second filter press, the refined coal is transported to the refined coal silo.

[0034] Furthermore, both the fixed carbon bin and the high-calorific-quality coal bin are connected to a dryer for drying the fixed carbon and high-calorific-quality coal to obtain fixed carbon products and high-calorific-quality coal products.

[0035] The gasification slag mixing tank, fine slag tank, coarse concentrate tank, concentrate tank, and clean coal tank are all connected to the clean water tank via gravity pipes or clean water pumps.

[0036] The water filtered out by the first and second filter presses is connected to the thickening tank via a gravity pipe or a slurry pump.

[0037] The thickening tank is connected to the clear water tank.

[0038] Furthermore, conveyor belts are installed between the feeding hopper and the gasification slag mixing tank, between the first vibrating screen and the glass crystal bin, between the second vibrating screen and the coarse tailings bin, between the third vibrating screen and the fixed carbon bin, and between the fourth vibrating screen and the high-calorific-quality coal bin.

[0039] Furthermore, the first vibrating screen, the second vibrating screen, the third vibrating screen, and the fourth vibrating screen are all high-frequency vibrating screens;

[0040] The first sorting unit, the second sorting unit, and the third sorting unit are single or multiple sorting machines connected in series. The sorting machines can be ordinary sorting machines, TPS interference bed sorting machines, or spiral sorting tanks.

[0041] The first filter press and the second filter press are one or more filter presses connected in series. The filter press can be a conventional filter press, a plate and frame filter press or a reverse-jet filter press.

[0042] The reuse production line is a non-fired brick production line and a coal mine solidified filler production line.

[0043] The dryer is a biomass dryer or a natural gas dryer.

[0044] This invention also provides a process for extracting and reusing gasification slag, employing the aforementioned gasification slag extraction and reuse system, characterized by the following steps:

[0045] Step 1: The gasification slag solids and water are mixed to form a gasification slag slurry;

[0046] Step 2: Separate the gasification slag slurry into coarse and fine slag to obtain glass crystals and fine slag;

[0047] Step 3: Mix the fine residue and water to obtain fine residue slurry;

[0048] Step 4: Separate the fine slurry to obtain coarse concentrate and coarse tailings;

[0049] Step 5: Mix the rough concentrate and water to obtain a rough concentrate slurry and fine tailings;

[0050] Step 6: Separate the crude concentrate slurry into concentrate and high-ash concentrate;

[0051] Step 7: Mix the concentrate and water to obtain a concentrate slurry;

[0052] Step 8: Separate the concentrate slurry to separate fixed carbon and high-calorific-quality thermal coal;

[0053] Step 9: Vibrate and dewater the fixed carbon, and dry the product on the screen to obtain fixed carbon; vibrate and dewater the high-calorific-quality coal, and dry the product on the screen to obtain high-calorific-quality coal; mix the clean coal and water that are screened out during the dewatering process of fixed carbon and high-calorific-quality coal to obtain clean coal slurry, and dewater the clean coal slurry to obtain clean coal product.

[0054] Furthermore, the fine slurry in step 3 is deslimed by a desliming screen and then sorted in step 4.

[0055] Furthermore, the water distribution rate during the preparation of the gasification slag slurry, fine slag slurry, coarse concentrate slurry, concentrate slurry, and clean coal slurry is 150-900 cubic meters per hour.

[0056] The gasification slag slurry and coarse tailings are fed into the first and second vibrating screens by gravity or by one or more slurry pumps for vibration dewatering and extraction.

[0057] The fine slag slurry, coarse concentrate slurry, and concentrate slurry are respectively fed into a single or multiple series-connected separator unit by gravity flow or by one or more mixed slurry pumps for separation and extraction.

[0058] The fine tailings and refined coal slurry are respectively fed into a filter press by a single or multiple slurry pumps for dewatering and extraction.

[0059] The fixed carbon and high-calorific-quality coal are extracted by gravity flow or by one or more slurry pumps into one or more third and fourth vibrating screens connected in series for vibration dehydration.

[0060] The vibration frequencies of the first, second, third, and fourth vibrating screens are all 960-1440 revolutions per minute;

[0061] The operating flow rate of the slurry pumps is 150-900 cubic meters per hour.

[0062] Compared with the prior art, the present invention has the following beneficial technical effects:

[0063] 1. The gasification slag extraction and reuse system provided by this invention enables solid waste recycling, especially the dehydration of gasification slag fines to turn waste into treasure. The overall energy consumption of the equipment is effectively reduced, the production process is improved, and the precise recovery rate is high. It can effectively promote the maximum utilization of energy, save water, save energy, reduce emissions, and is conducive to better environmental pollution control.

[0064] 2. The gasification slag extraction and reuse system and process provided by this invention can achieve a comprehensive extraction and utilization rate of over 95% for existing gasification slag in the coal chemical industry, far exceeding the industry average of approximately 50%. Specifically, the comprehensive utilization rate comprises approximately 40% for fixed carbon, approximately 25% for high-calorific-quality thermal coal, approximately 15% for glass crystals, and approximately 20% for the remaining tailings, which can be entirely used as raw material for non-fired bricks and as filler material for coal mine solidification products. Attached Figure Description

[0065] Figure 1 This is a schematic diagram of the gasification and slag extraction and reuse system of the present invention;

[0066] Figure label:

[0067] 1-Feeding hopper, 2-Gasification slag mixing tank, 3-First vibrating screen, 4-Fine slag tank, 5-Glass crystal bin, 6-First sorting unit, 7-Coarse concentrate tank, 8-Second vibrating screen, 9-Second sorting unit, 10-Fine tailings tank, 11-First filter press, 12-Concentrate tank, 13-High ash tank, 14-Third sorting unit, 15-First slurry pump, 16-Second slurry pump, 17-Third vibrating screen, 18-Fourth vibrating screen, 19-Fixed carbon bin, 20-High calorific value coal bin, 21-Clean coal tank, 22-Second filter press, 23-Clean coal bin, 24-Tailings bin, 25-Reuse production line, 26-Dryer, 27-Thickening tank, 28-Clear water tank, 29-Coarse tailings bin, 30-Desliming screen. Detailed Implementation

[0068] To make the objectives, advantages, and features of the present invention clearer, a detailed description of a gasification slag extraction and reuse system and process is provided below with reference to the accompanying drawings and specific embodiments. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0069] In the description of this invention, it should be noted that, unless otherwise expressly specified and limited, the terms “installation,” “connection,” and “linking” should be interpreted broadly, and the terms “first” and “second” are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0070] See Figure 1 A coal chemical gasification slag extraction and reuse system includes a feeding hopper 1, a gasification slag mixing tank 2, a first vibrating screen 3, a fine slag tank 4, a glass crystal bin 5, a first sorting unit 6, a coarse concentrate tank 7, a second vibrating screen 8, a second sorting unit 9, a fine tailings tank 10, a first filter press 11, a concentrate tank 12, a high ash tank 13, a third sorting unit 14, a first slurry pump 15, a second slurry pump 16, a third vibrating screen 17, a fourth vibrating screen 18, a fixed carbon bin 19, a high calorific value coal bin 20, a clean coal bin 21, a second filter press 22, a clean coal bin 23, a tailings bin 24, a dryer 26, a reuse production line 25, a thickener 27, a clear water bin 28, a coarse tailings bin 29, and a desliming screen 30.

[0071] The first vibrating screen 3, the second vibrating screen 8, the third vibrating screen 17, and the fourth vibrating screen 18 are all high-frequency vibrating screens; the first sorting unit 6, the second sorting unit 9, and the third sorting unit 14 are single or multiple sorting machines connected in series, and the sorting machines can be ordinary sorting machines, TPS interference bed sorting machines, or spiral sorting troughs; the first filter press 11 and the second filter press 22 are single or multiple filter presses connected in series, and the filter presses can be ordinary filter presses, plate and frame filter presses, or reverse-air filter presses. The reuse production line 25 is a non-fired brick production line and a coal mine solidified filler production line. The dryer 26 is a biomass dryer or a natural gas dryer.

[0072] The discharge port of the feeding hopper 1 is connected to the inlet of the gasification slag mixing tank 2 via a conveyor belt. The gasification slag solid and the water in the clear water tank 28 enter the gasification slag mixing tank 2 through the raw material inlet and water source inlet of the gasification slag mixing tank 2, respectively. The agitator in the gasification slag mixing tank 2 is used to adjust the slurry, so that the gasification slag is fully dispersed.

[0073] The outlet of the gasification slag mixing tank 2 is connected to the inlet of the first vibrating screen 3. The undersize outlet of the first vibrating screen 3 is connected to the fine slag tank 4, and the oversize outlet is connected to the glass crystal silo 5. The gasification slag slurry in the gasification slag mixing tank 2 is transported to the first vibrating screen 3, where the material is separated into fine and coarse slag under vibration. The first separations are fine slag of 0.05mm-0.3mm and glass crystals of 0.3mm-1.00mm. Alternatively, a conveyor belt can be installed at the oversize outlet of the first vibrating screen 3 to directly transport the separated glass crystals to the glass crystal silo 5. The obtained glass crystals can be used as raw materials for cement or concrete building materials.

[0074] The discharge port of the first vibrating screen 3 can also be preferentially connected to the feed port of the desliming screen 30. The discharge port of the desliming screen 30 is then connected to the fine slag pool 4. The fine slag separated by the first vibrating screen 3 is deslimed under the vibration of the desliming screen 30 and flows into the fine slag pool 4 by gravity. The water under the screen of the desliming screen 30 can flow into the thickening pool 27 by gravity or flow into the fine tailings pool 10 by gravity.

[0075] Water is introduced into the fine slag tank 4 through a pipeline from the clear water tank 28. The bottom outlet of the fine slag tank 4 is connected to the feed inlet of the first sorting unit 6, which transports the fine slag to the first sorting unit 6 for sorting to obtain coarse concentrate and coarse tailings. The coarse concentrate outlet of the first sorting unit 6 is connected to the coarse concentrate tank 7, and the coarse tailings outlet of the first sorting unit 6 is connected to the feed inlet of the second vibrating screen 8.

[0076] The second vibrating screen 8 further separates and dewaters the coarse tailings through vibration, obtaining tailings particles and tailings of 0.05mm-0.3mm. The oversize discharge port of the second vibrating screen 8 is connected to the inlet of the coarse tailings bin 29, and the undersize discharge port of the second vibrating screen 8 is connected to the fine tailings pool 10. A conveyor belt can be installed on the oversize discharge port of the second vibrating screen 8 to transport the 0.05mm-0.3mm tailings particles, reducing the number of manual and mechanical transfers. The tailings particles can be reused as new building materials and fillers for coal mine solidification products.

[0077] Water is introduced into the coarse concentrate pool 7 through a pipeline from the clear water pool 28. The bottom outlet of the coarse concentrate pool 7 is connected to the feed inlet of the second separator 9. The coarse concentrate slurry can be directly or transported to the second separator 9 through a slurry pump for further separation of concentrate and high ash.

[0078] The concentrate outlet of the second sorting unit 9 is connected to the feed inlet of the concentrate pool 12, and the obtained concentrate is further sorted and reused. The high ash outlet of the second sorting unit 9 is connected to the high ash pool 13, and the obtained high ash can be sold and reused as a high ash product, or transported to the fine tailings pool 10.

[0079] The bottom outlet of the fine tailings pond 10 is connected to the feed inlet of the first filter press 11, and the tailings mixed with high ash are dewatered through filter pressing. The discharge outlet of the first filter press 11 is connected to the feed inlet of the tailings bin 24, and the tailings pressed out by the first filter press 11 can be reused as new building materials and fillers for coal mine solidification products.

[0080] At the same time, the tailings and high ash in the tailings bin 24 can be fully mixed in the tailings bin 24 and then further transported to the reuse production line 25, which can be used to produce non-fired bricks or coal mine solidified products fillers for reuse in the non-fired brick production line or coal mine solidified products production line, and can efficiently utilize the coarse slag in the gasification slag.

[0081] Secondly, the clear water pool 28 introduces water into the concentrate pool 12 by gravity or by a clear water pump. The bottom outlet of the concentrate pool 12 is connected to the feed inlet of the third separator unit 14. The concentrate slurry can be directly or transported to the third separator unit 14 for separation, further separating fixed carbon and high-calorific-quality coal.

[0082] The fixed carbon outlet of the third sorting unit 14 is connected to the inlet of the first slurry pump 15. The outlet of the first slurry pump 15 is connected to the inlet of the third vibrating screen 17. The over-screen outlet of the third vibrating screen 17 is connected to the fixed carbon bin 19. A conveyor belt can be installed between the over-screen outlet of the third vibrating screen 17 and the fixed carbon bin 19 to transport the fixed carbon, reducing manual operation and mechanical transfer. The sorted fixed carbon slurry is mixed by the first slurry pump 15 and pumped into the third vibrating screen 17, where the fixed carbon is screened out.

[0083] The high-calorific-quality coal discharge port of the third sorting unit 14 is connected to the inlet of the second slurry pump 16. The discharge port of the second slurry pump 16 is connected to the inlet of the fourth vibrating screen 18. The discharge port of the fourth vibrating screen 18 is connected to the high-calorific-quality coal storage 20. A conveyor belt can also be installed between the discharge port of the fourth vibrating screen 18 and the high-calorific-quality coal storage 20 to transport the high-calorific-quality coal, reducing the number of manual operations and mechanical transfers. The sorted high-calorific-quality coal slurry is mixed by the second slurry pump 16 and pumped into the fourth vibrating screen 18, where it is screened out.

[0084] The fixed carbon bin 19 and the high-calorific-quality coal bin 20 can be dried by the dryer 26 to obtain fixed carbon products and high-calorific-quality coal products.

[0085] The under-screen discharge ports of the third vibrating screen 17 and the fourth vibrating screen 18 are both connected to the feed inlet of the clean coal pool 21 to obtain a mixed clean coal slurry. The underflow port of the clean coal pool 21 is connected to the second filter press 22. After the clean coal is dewatered by the second filter press 22, it flows by gravity or is transported to the clean coal bin 23 to obtain the clean coal product.

[0086] In this system, all water collected from filter press dewatering, vibration dewatering, or sedimentation is connected to the thickening tank 27 via pipelines or slurry pumps. After sedimentation in the thickening tank, the water flows into the clear water tank 28 and is then circulated back to the system to provide water. A thickener is installed in the center of the thickening tank, and a scraper conveyor is installed at the bottom. The scraper conveyor scrapes the thickened tailings onto the low-flow pipe of the central column, which is connected to one or more slurry pumps at a rate of 150-900 cubic meters per hour to pump the tailings into one or more filter presses. The tailings are then pressed out and used as filler for new building materials and coal mine solidification products.

[0087] In summary, the coal chemical gasification slag extraction and reuse system provided by this invention separates glass crystals, high ash, tailings, fixed carbon, high calorific value coal and clean coal products, as well as non-fired bricks or coal mine solidified fillers obtained by reusing coarse slag, coarse tailings and high ash.

[0088] The specific process steps for reusing gasification slag using the above-mentioned gasification slag extraction and reuse system are as follows:

[0089] Step 1: The gasification slag solid is conveyed to the feeding hopper 1.

[0090] Step 2: The gasification slag solid and water enter the gasification slag mixing tank 2 through the raw material inlet and water source inlet, respectively. The agitator in the gasification slag mixing tank 2 is used to adjust the slurry so that the gasification slag is fully dispersed.

[0091] A conveyor belt is installed at the discharge port of the feed hopper 1 to transport the gasification slag to the gasification slag mixing tank 2; 150-900 cubic meters of clean water are added to the gasification slag mixing tank 2 according to the amount of solid gasification slag.

[0092] Step 3: The gasification slag slurry is conveyed to the high-frequency first vibrating screen 3. Under the action of vibration, the material is separated into coarse slag and fine slag to obtain glass crystals and fine slag.

[0093] The gasification slag slurry can be fed into the first vibrating screen 3 by gravity or by one or more slurry pumps. The frequency of the first vibrating screen 3 is 960-1440 rpm. Under the action of vibration, the material is separated into fine slag and coarse slag. The 0.3mm-1.00mm glass crystals separated by gravity or by a conveyor belt are directly transported to the glass crystal bin 5 from the discharge port on the screen. The under-screen discharge port flows into the fine slag pool 4 by gravity.

[0094] The discharge port of the first vibrating screen 3 can also be preferentially connected to the feed port of the desliming screen 30. The discharge port of the desliming screen 30 is then connected to the fine slag pool 4. The fine slag separated by the first vibrating screen 3 is deslimed under the vibration of the desliming screen 30 and flows into the fine slag pool 4 by gravity. The water under the screen of the desliming screen 30 can flow into the thickening pool 27 by gravity or flow into the fine tailings pool 10 by gravity.

[0095] Step 4: Transport the glass crystals to the glass crystal chamber (5); at the same time, the fine slag and water are introduced into the fine slag tank 4 through the raw material inlet and water source inlet, respectively, and the slurry is adjusted in the fine slag tank 4 so that the fine slag is fully dispersed.

[0096] Depending on the amount of fine slag, add 150-900 cubic meters of clean water per hour to the fine slag tank 4 and stir thoroughly.

[0097] Step 5: The fine slurry is fed into the first separator unit 6 by gravity or by one or more slurry pumps for separation to obtain coarse concentrate and coarse tailings.

[0098] Step 6: The obtained coarse tailings are allowed to flow by gravity or be conveyed to the high-frequency second vibrating screen 8 for dewatering. The frequency of the second vibrating screen 8 is 960-1440 rpm, resulting in tailings particles and tailings of 0.05mm-0.3mm.

[0099] Step 7: The tailings particles separated by the second vibrating screen 8 are transported by gravity or by conveyor belt to the coarse tailings bin 29, and the tailings under the screen are transported to the fine tailings pool 10.

[0100] Step 8: The crude concentrate obtained in step 5 and water are introduced into the crude concentrate pool 7 through the raw material inlet and water inlet, respectively, so that the crude concentrate is fully dispersed.

[0101] Depending on the amount of fine slag, 150-900 cubic meters of clean water are added to the rough concentrate pool 7 and stirred thoroughly every hour.

[0102] Step 9: The coarse concentrate slurry is fed into the second separator 9 by gravity or by one or more mixed slurry pumps for further separation of concentrate and high ash.

[0103] Step 10: The high-ash material separated is transported to the high-ash pond 13 for sale as a high-ash product, or flows by gravity to the fine tailings pond 10 and mixed with the tailings obtained in step 7. The mixture is then pumped into the first filter press 11 in series by one or more slurry pumps for dewatering and filtration. The mixture is then sent to the reuse production line 25, i.e., the non-fired brick production line or the coal mine solidified product production line, to reuse the non-fired bricks or coal mine solidified product fillers. The tailings are pressed out to be used as new building materials and coal mine solidified product fillers.

[0104] Step 11: The concentrate obtained in step 9 and water are introduced into the concentrate tank 12 through the raw material inlet and water inlet, respectively, so that the concentrate is fully dispersed.

[0105] Depending on the amount of fine slag, 150-900 cubic meters of clean water are added to concentrate pool 12 and stirred thoroughly every hour.

[0106] Step 12: The concentrate slurry is fed into the third separator unit 14 by gravity or by one or more mixed slurry pumps for further separation of fixed carbon and high-calorific-quality coal.

[0107] Step 13: After the fixed carbon is pumped into the tank by gravity or by the first slurry pump 15 and stirred, it is conveyed to the third vibrating screen 17 for vibration and dewatering. The fixed carbon on the screen is dried by the dryer 26 and then conveyed to the fixed carbon bin 19 by gravity or by the conveyor belt.

[0108] Meanwhile, high-calorific-quality coal is either drawn into the pool by gravity or pumped into the pool by the second slurry pump 16 and stirred before being conveyed to the fourth vibrating screen 18 for dewatering. The high-calorific-quality coal on the screen is dried by the dryer 26 and then drawn by gravity or conveyed to the high-calorific-quality coal silo 20 by conveyor belt.

[0109] Step 14: Connect the discharge ports of the third vibrating screen 17 and the fourth vibrating screen 18 to the clean coal pool 21, and connect a water source to fully disperse the clean coal. Add 150-900 cubic meters of clean water per hour to the clean coal pool 21 according to the amount of clean coal, and stir it thoroughly to form a clean coal slurry.

[0110] Step 15: The clean coal slurry is fed into the second filter press 22 by gravity or by one or more slurry pumps in series. After dewatering, it is transported to the clean coal bin 23 to obtain the clean coal product.

[0111] After secondary separation, the concentrate and high ash may not be further separated. The obtained concentrate and high ash can be fed into a vibrating screen for dewatering by gravity or by one or more slurry pumps. The undersized clean coal slurry is fed into one or more second filter presses 22 connected in series by one or more slurry pumps. After dewatering, it is fed into the clean coal bin 23 by gravity or by conveying to obtain the clean coal product.

[0112] In summary, the material enters the gasification slag mixing tank evenly from the feed hopper. After being washed and mixed, it enters the high-frequency vibrating screen for separation. The coarse slag on the upper part of the screen is sent to the non-fired brick production line, and the undersize slag enters the TPS washing and screening equipment. It uses interference sedimentation to separate the materials according to density. No medium is required. The water flow sprayed from hundreds of high-pressure nozzles at the bottom forms turbulence and interacts with the gasification slag particles to achieve interference sedimentation.

[0113] This method separates and extracts glass crystals, coarse tailings particles, high ash, fine tailings, fixed carbon, high calorific value coal, and refined coal products from tailings bins. The coarse slag, coarse tailings, and high ash are then dehydrated using a high-pressure reverse-flushing filter press before being fed into a non-fired brick production line (batching machine—feeding machine—mixer—belt conveyor—brick press—brick blank—curing—finished product—shipping) to obtain non-fired bricks.

[0114] The system of this invention has a simple operation, high recovery rate, low investment, low energy consumption, and low operating cost. It can achieve the goal of synergistic efficiency in reducing pollution and carbon emissions, and can also achieve the long-term goal of carbon peaking and carbon neutrality. At the same time, it turns gasification slag from harm to benefit and waste into treasure.

[0115] This invention extracts energy and carbon elements from solid waste, reducing resource and energy losses, as well as solid waste emissions and the land occupation required for traditional landfills, thus mitigating environmental pollution and risks. The extracted fixed carbon is high-quality fixed carbon for activated carbon production, and the extracted coal is high-quality coal for power plants and thermal power plants. The extracted glass crystals are high-quality glass crystals for ceramic and cement plants. Tailings are used to produce new building materials and coal mine solidification fillers. The produced new building material, non-fired bricks, replaces traditional sintered bricks, and the produced coal mine solidification fillers fill subsidence areas and mining areas in coal mines.

[0116] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present invention.

Claims

1. A system for extracting and reusing gasification slag, characterized in that: It includes a clear water tank (28), a gasification slag mixing tank (2), a first vibrating screen (3), a first sorting unit (6), a second sorting unit (9), and a second filter press (22); The clear water tank (28) is used to supply water to the system; The outlet of the gasification slag mixing tank (2) is connected to the inlet of the first vibrating screen (3); The undersize discharge port of the first vibrating screen (3) is connected to the feed port of the first sorting unit (6); The coarse concentrate outlet of the first sorting unit (6) is connected to the feed inlet of the second sorting unit (9); The concentrate outlet of the second sorting unit (9) is connected to the second filter press (22); It includes a feeding hopper (1), a fine slag pool (4), a glass crystal bin (5), a coarse concentrate pool (7), a second vibrating screen (8), a fine tailings pool (10), a first filter press (11), a concentrate pool (12), a high ash pool (13), a first slurry pump (15), a second slurry pump (16), a fixed carbon bin (19), a high calorific value coal bin (20), a clean coal pool (21), a clean coal bin (23), a tailings bin (24), a dryer (26), a recycling production line (25), and a coarse tailings bin (29). The discharge port of the feeding hopper (1) is connected to the inlet of the gasification slag mixing tank (2); The under-screen outlet of the first vibrating screen (3) is connected to the fine slag tank (4), and the over-screen outlet is connected to the glass crystal chamber (5). The underflow outlet of the fine slag tank (4) is connected to the feed inlet of the first sorting unit (6); The coarse concentrate outlet of the first sorting unit (6) is connected to the coarse concentrate pool (7), and the coarse tailings outlet of the first sorting unit (6) is connected to the feed inlet of the second vibrating screen (8). The upper discharge port of the second vibrating screen (8) is connected to the feed port of the coarse tailings bin (29), and the lower discharge port of the second vibrating screen (8) is connected to the fine tailings pool (10). The bottom outlet of the rough concentrate pool (7) is connected to the feed inlet of the second separator unit (9); The concentrate outlet of the second sorting unit (9) is connected to the feed inlet of the concentrate pool (12), and the high ash outlet of the second sorting unit (9) is connected to the high ash pool (13) or the fine tailings pool (10). The bottom outlet of the fine tailings pond (10) is connected to the feed inlet of the first filter press (11); the discharge outlet of the first filter press (11) is connected to the feed inlet of the tailings bin (24); and the discharge outlet of the tailings bin (24) is connected to the recycling production line (25). The bottom outlet of the concentrate pool (12) is connected to the feed inlet of the third separator unit (14); The fixed carbon outlet of the third sorting unit (14) is connected to the inlet of the first slurry pump (15), the outlet of the first slurry pump (15) is connected to the inlet of the third vibrating screen (17), and the on-screen outlet of the third vibrating screen (17) is connected to the fixed carbon bin (19). The high-calorific-quality coal outlet of the third sorting unit (14) is connected to the inlet of the second slurry pump (16), the outlet of the second slurry pump (16) is connected to the inlet of the fourth vibrating screen (18), and the on-screen outlet of the fourth vibrating screen (18) is connected to the high-calorific-quality coal bin (20). The under-screen discharge ports of the third vibrating screen (17) and the fourth vibrating screen (18) are both connected to the feed inlet of the clean coal pool (21). The bottom outlet of the refined coal pool (21) is connected to the second filter press (22). After the refined coal is dewatered by the second filter press (22), it is transported to the refined coal silo (23). Conveyor belts are installed between the feeding hopper (1) and the gasification slag mixing tank (2), between the first vibrating screen (3) and the glass crystal bin (5), between the second vibrating screen (8) and the coarse tailings bin (29), between the third vibrating screen (17) and the fixed carbon bin (19), and between the fourth vibrating screen (18) and the high calorific value coal bin (20).

2. The gasification slag extraction and reuse system according to claim 1, characterized in that: It includes the third sorting unit (14), the third vibrating screen (17) and the fourth vibrating screen (18); The concentrate outlet of the second sorting unit (9) is connected to the feed inlet of the third sorting unit (14); The fixed carbon outlet of the third sorting unit (14) is connected to the feed inlet of the third vibrating screen (17); The high-calorific-quality coal outlet of the third sorting unit (14) is connected to the feed inlet of the fourth vibrating screen (18); The under-screen discharge ports of the third vibrating screen (17) and the fourth vibrating screen (18) are both connected to the second filter press (22).

3. The gasification slag extraction and reuse system according to claim 2, characterized in that: Including a desliming screen (30); The discharge port of the first vibrating screen (3) is connected to the feed port of the desliming screen (30), and the discharge port of the desliming screen (30) is connected to the fine slag tank (4). The water screened by the desliming screen (30) enters the thickening tank (27) or the fine tailings tank (10) through a gravity flow pipe or a slurry pump.

4. The gasification slag extraction and reuse system according to claim 3, characterized in that: The fixed carbon bin (19) and the high calorific value coal bin (20) are both connected to the dryer (26) for drying the fixed carbon and high calorific value coal to obtain fixed carbon products and high calorific value coal products. The gasification slag mixing tank (2), fine slag tank (4), coarse concentrate tank (7), concentrate tank (12) and clean coal tank (21) are all connected to the clean water tank (28) via gravity pipes or clean water pumps; The water filtered out by the first filter press (11) and the second filter press (22) is connected to the thickening tank (27) through a gravity flow pipe or a slurry pump; The thickening tank (27) is connected to the clear water tank (28).

5. The gasification slag extraction and reuse system according to claim 4, characterized in that: The first vibrating screen (3), the second vibrating screen (8), the third vibrating screen (17) and the fourth vibrating screen (18) are all high-frequency vibrating screens; The first sorting unit (6), the second sorting unit (9) and the third sorting unit (14) are single or multiple sorting machines connected in series. The sorting machines can be ordinary sorting machines, TPS interference bed sorting machines or spiral sorting tanks. The first filter press (11) and the second filter press (22) are one or more filter presses connected in series. The filter presses can be ordinary filter presses, plate and frame filter presses or reverse-jet filter presses. The reuse production line (25) is a non-fired brick production line and a coal mine solidified filler production line; The dryer (26) is a biomass dryer or a natural gas dryer.

6. A process for extracting and reusing gasification slag, utilizing the gasification slag extraction and reuse system according to any one of claims 1-5, characterized in that, Includes the following steps: Step 1: The gasification slag solids and water are mixed to form a gasification slag slurry; Step 2: Separate the gasification slag slurry into coarse and fine slag to obtain glass crystals and fine slag; Step 3: Mix the fine residue and water to obtain fine residue slurry; Step 4: Separate the fine slurry to obtain coarse concentrate and coarse tailings; Step 5: Mix the rough concentrate and water to obtain a rough concentrate slurry and fine tailings; Step 6: Separate the crude concentrate slurry into concentrate and high-ash concentrate; Step 7: Mix the concentrate and water to obtain a concentrate slurry; Step 8: Separate the concentrate slurry to separate fixed carbon and high-calorific-quality thermal coal; Step 9: Vibrate and dewater the fixed carbon, and dry the product on the screen to obtain fixed carbon; vibrate and dewater the high-calorific-quality coal, and dry the product on the screen to obtain high-calorific-quality coal; mix the clean coal and water that are screened out during the dewatering process of fixed carbon and high-calorific-quality coal to obtain clean coal slurry, and dewater the clean coal slurry to obtain clean coal product.

7. The gasification slag extraction and reuse process according to claim 6, characterized in that: After the fine slurry in step 3 is deslimed by a desliming screen, it is then sorted in step 4.

8. The gasification slag extraction and reuse process according to claim 7, characterized in that: The water distribution rate during the preparation of the gasification slag slurry, fine slag slurry, coarse concentrate slurry, concentrate slurry, and clean coal slurry is 150-900 cubic meters per hour. The gasification slag slurry and coarse tailings are fed into the first vibrating screen (3) and the second vibrating screen (8) by gravity flow or by one or more slurry pumps for vibration dewatering and extraction. The fine slag slurry, coarse concentrate slurry, and concentrate slurry are respectively fed into a single or multiple series-connected separator unit by gravity flow or by one or more mixed slurry pumps for separation and extraction. The fine tailings and refined coal slurry are respectively fed into a filter press by a single or multiple slurry pumps for dewatering and extraction. The fixed carbon and high-calorific-quality coal are extracted by gravity flow or by one or more slurry pumps into one or more third vibrating screens (17) and fourth vibrating screens (18) connected in series for vibration dehydration. The vibration frequencies of the first vibrating screen (3), the second vibrating screen (8), the third vibrating screen (17) and the fourth vibrating screen (18) are all 960-1440 revolutions per minute; The operating flow rate of the slurry pumps is 150-900 cubic meters per hour.

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