Electric heating semi-coke oven for low rank coal dry distillation
By using green electricity as a heat source in an electrically heated semi-coke oven, combined with interlocking control and a dual-compartment dual-valve structure, the problems of inaccurate temperature control and poor environmental performance in the dry distillation of low-rank pulverized coal in traditional semi-coke ovens have been solved, realizing an energy-saving and environmentally friendly dry distillation process for low-rank pulverized coal.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SINOSTEEL ANSHAN RES INST OF THERMO ENERGY CO LTD
- Filing Date
- 2025-07-03
- Publication Date
- 2026-06-26
AI Technical Summary
Traditional internally heated semi-coke ovens have poor production stability, difficult temperature control, poor environmental performance, and serious heat source pollution during the dry distillation of low-rank pulverized coal.
An electrically heated semi-coke oven is adopted, using green electricity as a heat source. Through the interlocking control of the electric heating device and the temperature measuring device, the temperature of the dry distillation zone is precisely controlled. A coal feeding system with a double compartment and double valve structure is adopted to prevent coal gas from escaping and reduce equipment investment costs.
It achieves energy saving and pollution-free operation in the dry distillation process of low-rank pulverized coal, ensures uniform heating of materials, improves environmental friendliness, and reduces investment costs.
Smart Images
Figure CN224411684U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of low-rank coal dry distillation technology, and in particular to an electrically heated semi-coke oven for low-rank pulverized coal dry distillation. Background Technology
[0002] Low-rank coal dry distillation technology is a process that converts low-rank coal (such as lignite, long-flame coal, and non-caking coal) into semi-coke, coal tar, and coal gas through medium- and low-temperature pyrolysis (500–800℃). This technology can significantly improve the resource value of low-rank coal, enable graded utilization, and reduce pollution from direct combustion.
[0003] Low-rank pulverized coal (low-rank coal powder with a particle size of less than 3mm) has low direct utilization efficiency and high pollution due to its high moisture content, high volatile matter, and low calorific value. Through technologies such as dry distillation, gasification, and molding, it can be transformed into high-value-added products. For example, semi-coke can be used for calcium carbide, ferroalloys, and domestic fuel, tar can be further processed to produce fuel oil or chemical raw materials, and coal gas can be used as fuel or syngas, thereby achieving efficient utilization of resources.
[0004] Semi-coke ovens are classified into internally heated ovens, externally heated ovens, and moving bed / fluidized bed ovens. Internally heated semi-coke ovens are commonly used for the dry distillation of low-rank coal powder, and the heat source for these ovens is typically hot flue gas. For example, Chinese patent application CN116004263A discloses a "high-temperature pyrolysis circular semi-coke oven for low-rank coal," consisting of several independent gasifiers arranged in a rectangular array with two rows and multiple columns. Conveying mechanisms are located at the top and bottom of both sides of the rectangular array. Each gasifier has a vibrating screen in its feed bin; undersize material enters the gasifier, while oversize material is uniformly transported out via the upper conveying mechanism. The discharge port at the bottom of each gasifier discharges material to the lower conveying mechanism for unified external transport. Each gasifier is equipped with a gas collection pipe, all of which are connected to a main gas collection pipe to uniformly send the collected gas into a gas purification system. The gasifier requires heat from the direct combustion of oxygen-enriched pyrolysis agent and lump coal during ignition. When the pyrolysis temperature in the furnace reaches 1200℃, the hot flue gas rises. When the temperature exceeds 850℃, the upper lump coal undergoes dry distillation to form semi-coke and produces a portion of producer gas. Since the pyrolysis products of coal between 550 and 850℃ are mainly tar, softened water pipes are installed for heat exchange, and the temperature of the medium-temperature dry distillation chamber can be controlled between 350 and 550℃ for pyrolysis.
[0005] Traditional internally heated semi-coke ovens have poor production stability, the temperature in the dry distillation zone is difficult to control, and they are not environmentally friendly. Summary of the Invention
[0006] This utility model provides an electrically heated semi-coke oven for the dry distillation of low-rank pulverized coal. The semi-coke oven uses green electricity to provide heat, which is energy-saving and pollution-free. The temperature control of the dry distillation zone is precise and the material is heated evenly. Multiple carbonization chambers share a single coal feeding system and coke discharge system, which reduces investment costs. The coal feeding system adopts a double-compartment double-valve structure, which can effectively prevent coal gas from escaping and improve environmental protection.
[0007] To achieve the above objectives, the present invention adopts the following technical solution:
[0008] An electrically heated semi-coke oven for the dry distillation of low-rank pulverized coal includes a coal feeding system, a semi-coke oven, and a coke discharge system connected sequentially from top to bottom. Multiple carbonization chambers and electrically heated chambers are arranged alternately within the oven body of the semi-coke oven. Each carbonization chamber has electrically heated chambers on both sides, and each electrically heated chamber is equipped with an electrically heated device. Multiple temperature measuring ports are provided on the oven wall of the semi-coke oven for installing temperature measuring devices, and the electrically heated devices are interlocked with the temperature measuring devices. The coal feeding system adopts a double-compartment, double-valve structure.
[0009] A gas outlet is located at the center of the top of the carbonization chamber, and several feed inlets are located around the gas outlet. The feeding system consists of an upper coal bunker, a first coal discharge valve, a lower coal bunker, a second coal discharge valve, and a coal discharge chute. The discharge port at the bottom of the upper coal bunker is connected to the feed inlet at the top of the lower coal bunker through the first coal discharge valve, and the discharge port at the bottom of the lower coal bunker is connected to the feed inlet of the coal discharge chute through the second coal discharge valve. The discharge ports of the coal discharge chute and the feed inlets of the carbonization chamber are set up one-to-one.
[0010] The gas outlet is connected to the gas purification system via a gas pipeline. An ammonia spray device is installed in the gas pipeline near the gas outlet. The gas pipeline is equipped with a pressure detection device, a temperature detection device, a flow detection device, and a flow regulating valve. The flow regulating valve is interlocked with the pressure detection device and the flow detection device.
[0011] The electric heating device includes multiple vertically arranged electric heaters, which are evenly spaced within the electric heating chamber. The electric heaters in the same electric heating device are divided into several groups, and each group of electric heaters is connected to the same temperature control device. Each carbonization chamber is equipped with several temperature measuring devices, and the temperature control device is interlocked with the corresponding temperature measuring device.
[0012] Each electric heater consists of a ceramic rod and an electric heating wire wound around the ceramic rod.
[0013] A refractory material layer is provided between the electric heating chamber and the carbonization chamber.
[0014] The furnace wall of the semi-coke oven consists of a steel structure shell, a refractory brick wall, and an insulation layer arranged sequentially from the outside to the inside.
[0015] Each carbonization chamber is equipped with a conical hopper at the bottom; the coke discharge system consists of a screw conveyor, a coke discharge bin, and a coke discharge valve. The screw conveyor is located below the conical hopper along the arrangement direction of the conical hoppers. The drive end of the screw conveyor is equipped with a motor. The discharge end of the screw conveyor is connected to the feed inlet at the top of the coke discharge bin. A coke discharge valve is located at the discharge outlet at the bottom of the coke discharge bin.
[0016] Compared with the prior art, the beneficial effects of this utility model are:
[0017] 1) The semi-coke oven uses green electricity as a heat source, which is energy-saving and pollution-free compared with the conventional semi-coke oven that uses hot flue gas as a heat source, and is conducive to the sustainable development of the industry.
[0018] 2) Through the interlocking control of electric heating device and temperature measuring device, the temperature of the dry distillation zone is precisely controlled. Electric heating devices are evenly distributed on both sides of each carbonization chamber, so that the material is heated evenly.
[0019] 3) Multiple carbonization chambers share a single coal feeding device and coke discharge device, and the coal feeding device adopts a double-compartment double-valve structure, which effectively prevents coal gas from escaping, improves environmental protection, and reduces investment costs. Attached Figure Description
[0020] Figure 1 This is a schematic diagram of the structure of an electrically heated low-rank coal dry distillation semi-coke oven according to the present invention.
[0021] Figure 2 yes Figure 1 AA view in the middle.
[0022] In the diagram: 1-Upper coal bunker; 2-Coal discharge valve one; 3-Lower coal bunker; 4-Coal discharge valve two; 5-Coal discharge chute; 6-Ceramic rod; 7-Electric heater; 8-Furnace body; 8.1-Carbonization chamber; 8.2-Electric heating chamber; 8.3-Insulation layer; 8.4-Refractory brick wall; 8.5-Steel structure shell; 8.6-Refractory material layer; 9-Conical hopper; 10-Screw conveyor; 11-Motor; 12-Coke discharge bin; 13-Coke discharge valve; 14-Temperature measuring port; 15-Gas outlet. Detailed Implementation
[0023] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings:
[0024] like Figure 1 , Figure 2As shown, the electric heating semi-coke oven for low-rank pulverized coal dry distillation of this utility model includes a coal feeding system, a semi-coke oven, and a coke discharge system connected sequentially from top to bottom; the semi-coke oven has multiple carbonization chambers 8.1 and electric heating chambers 8.2 arranged alternately inside the oven body, and each carbonization chamber 8.1 has electric heating chambers 8.2 on both sides, and electric heating devices are installed in the electric heating chambers 8.2; multiple temperature measuring ports 14 are provided on the oven wall of the semi-coke oven for installing temperature measuring devices, and the electric heating devices are interlocked with the temperature measuring devices; the coal feeding system adopts a double-compartment double-valve structure.
[0025] A gas outlet 15 is provided at the top center of the carbonization chamber 8.1, and several feed inlets are provided around the gas outlet 15. The feeding system consists of an upper coal bunker 1, a first coal discharge valve 2, a lower coal bunker 3, a second coal discharge valve 4, and a coal discharge chute 5. The discharge port at the bottom of the upper coal bunker 1 is connected to the feed inlet at the top of the lower coal bunker 3 through the first coal discharge valve 2, and the discharge port at the bottom of the lower coal bunker 3 is connected to the feed inlet of the coal discharge chute 5 through the second coal discharge valve 4. The discharge port of the coal discharge chute 5 is set in a one-to-one correspondence with the feed inlet of the carbonization chamber 8.1.
[0026] The gas outlet 15 is connected to the gas purification system via a gas pipeline. An ammonia spray device is installed in the gas pipeline near the gas outlet 15. A pressure detection device, a temperature detection device, a flow detection device, and a flow regulating valve are installed on the gas pipeline. The flow regulating valve is interlocked with the pressure detection device and the flow detection device.
[0027] The electric heating device includes multiple vertically arranged electric heaters 7, which are evenly spaced within the electric heating chamber 8.2. The electric heaters 7 in the same electric heating device are divided into several groups, and each group of electric heaters is connected to the same temperature control device. Each carbonization chamber 8.1 is equipped with several temperature measuring devices, and the temperature control device is interlocked with the corresponding temperature measuring device.
[0028] Each electric heater 7 consists of a ceramic rod and an electric heating wire wound around the ceramic rod.
[0029] A refractory material layer is provided between the electric heating chamber 8.2 and the carbonization chamber 8.1.
[0030] The furnace wall of the semi-coke oven consists of a steel structure shell 8.5, a refractory brick wall 8.4, and a heat insulation layer 8.3 arranged sequentially from the outside to the inside.
[0031] Each carbonization chamber 8.1 is equipped with a conical hopper 9 at its bottom; the coking system consists of a screw conveyor 10, a coking bin 12, and a coking valve 13. The screw conveyor 10 is located below the conical hopper 9 along the arrangement direction of the conical hopper 9. The drive end of the screw conveyor 10 is equipped with a motor 11. The discharge end of the screw conveyor 10 is connected to the feed inlet at the top of the coking bin 12. The discharge valve 13 is located at the discharge outlet at the bottom of the coking bin 12.
[0032] The method for dry distillation of low-rank coal powder using an electrically heated semi-coke oven for dry distillation of low-rank coal, as described in this utility model, is as follows:
[0033] 1) The low-rank pulverized coal transported by the coal preparation unit enters the upper coal bunker 1, and enters the lower coal bunker 3 through the coal discharge valve 12. Then, the coal discharge valve 12 is closed and the coal discharge valve 24 is opened. The low-rank pulverized coal in the lower coal bunker 3 enters the corresponding carbonization chamber 8.1 through multiple discharge ports of the coal discharge chute 5, thus achieving uniform material distribution.
[0034] 2) The low-rank pulverized coal entering the carbonization chamber 8.1 moves from top to bottom. The low-rank pulverized coal is heated by the electric heating devices in the electric heating chambers 8.2 on both sides of the carbonization chamber 8.1. The low-rank pulverized coal is heated to 340-360°C in the preheating section at the top of the carbonization chamber 8.1. The low-rank pulverized coal moves downward to the dry distillation section in the middle of the carbonization chamber 8.1 and is heated to 650-780°C to form semi-coke. The heating temperature of the preheating section and the dry distillation section is precisely controlled by the group temperature control of the electric heater 7 and the interlocking control between the electric heating device and the temperature measuring device.
[0035] 3) The semi-coke continues to move downwards, and after passing through the cooling section at the bottom of the carbonization chamber 8.1, it is cooled to below 200°C and discharged from the cone hopper 9. The semi-coke is then continuously transported to the coke discharge bin 12 by the screw conveyor 10, and then discharged through the coke discharge valve 13 to the subsequent semi-coke cooling system.
[0036] 4) The coal gas generated during the dry distillation of low-rank pulverized coal enters the coal gas pipeline through coal gas outlet 15. The coal gas is cooled to 70-80°C by spraying circulating ammonia water. The cooled coal gas and the condensed ammonia water coal tar mixture enter the coal gas purification system together. The flow detection device, pressure detection device and flow regulating valve on the coal gas pipeline are interlocked to regulate the pressure and flow of the coal gas pipeline.
[0037] The electric heating semi-coke oven for low-rank pulverized coal dry distillation described in this utility model mainly includes a semi-coke oven, a coal feeding system, a coke discharge system, and a coal gas discharge system.
[0038] The semi-coke oven includes multiple carbonization chambers 8.1, each a vertically arranged low-rank pulverized coal feeding channel. Electric heating devices are installed in the electric heating chambers 8.2 on both sides of the carbonization chambers 8.1, and these devices are connected to an external power source. Temperature measuring ports 14 are provided on the furnace wall for installing temperature measuring devices. Through interlocking control between the temperature measuring devices and the electric heating devices, the temperature within the carbonization chambers 8.1 is precisely controlled, effectively improving the coking yield.
[0039] The carbonization chamber 8.1 is equipped with a feed inlet and a gas outlet 15 at the top. The coal feeding system is designed with a double-chamber, double-valve structure to prevent gas leakage. The coke discharge system consists of a screw conveyor 10 and a coke discharge bin 12. A conical hopper 9 is located at the bottom of the carbonization chamber 8.1, and the screw conveyor 10 is installed below the conical hopper 9 to transport the semi-coke after dry distillation to the coke discharge bin 12. Multiple carbonization chambers 8.1 share one coal feeding system and one coke discharge system, which can effectively reduce equipment investment costs.
[0040] In this invention, the core technology is the use of electric heating in the semi-coke oven. The interior of the semi-coke oven is divided into a carbonization chamber 8.1 and an electric heating chamber 8.2. An electric heating device is installed in the electric heating chamber 8.2, and the heat generated by the electric heating device is used as a heat source to ensure that the low-rank pulverized coal is heated more evenly.
[0041] The semi-coke oven can have a square or circular cross-section, and its inner wall is provided with a heat insulation layer 8.3 made of refractory insulation material. A refractory material layer 8.6 is filled between the electric heating chamber 8.2 and the carbonization chamber 8.1. The main body of the electric heater 7 is made of a ceramic rod that does not deform easily at high temperatures, and then electric heating wires are wound around it. The electric heaters 7 are grouped for temperature control to ensure precise temperature control in each part of the carbonization chamber 8.1.
[0042] The gas exhaust system located on the top of the semi-coke oven mainly consists of a gas pipeline, an ammonia spray device installed inside the gas pipeline, and pressure detection devices, temperature detection devices, flow detection devices, and flow control valves installed on the gas pipeline. It is used to smoothly exhaust the gas generated during the dry distillation of low-rank coal to the gas purification system.
[0043] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and inventive concept of the present utility model, should be included within the protection scope of the present utility model.
Claims
1. An electrically heated semi-coke oven for the dry distillation of low-rank pulverized coal, comprising a coal feeding system, a semi-coke oven, and a coke discharge system connected sequentially from top to bottom; characterized in that, The semi-coke oven has multiple carbonization chambers and electric heating chambers arranged alternately inside the oven body. Each carbonization chamber has an electric heating chamber on both sides, and an electric heating device is installed in the electric heating chamber. Multiple temperature measuring ports are provided on the oven wall of the semi-coke oven for installing temperature measuring devices. The electric heating devices are interlocked with the temperature measuring devices. The coal feeding system adopts a double-compartment double-valve structure. A gas outlet is located at the center of the top of the carbonization chamber, and several feed inlets are located around the gas outlet. The coal feeding system consists of a coal feeding bunker, a first coal discharge valve, a lower coal bunker, a second coal discharge valve, and a coal discharge chute. The discharge port at the bottom of the coal feeding bunker is connected to the feed inlet at the top of the lower coal bunker through the first coal discharge valve, and the discharge port at the bottom of the lower coal bunker is connected to the feed inlet of the coal discharge chute through the second coal discharge valve. The discharge ports of the coal discharge chute and the feed inlets of the carbonization chamber are set up one-to-one. The gas outlet is connected to the gas purification system via a gas pipeline. An ammonia spray device is installed in the gas pipeline near the gas outlet. The gas pipeline is equipped with a pressure detection device, a temperature detection device, a flow detection device, and a flow regulating valve. The flow regulating valve is interlocked with the pressure detection device and the flow detection device. The electric heating device includes multiple vertically arranged electric heaters, which are evenly spaced within the electric heating chamber. The electric heaters in the same electric heating device are divided into several groups, and each group of electric heaters is connected to the same temperature control device. Each carbonization chamber is equipped with several temperature measuring devices, and the temperature control device is interlocked with the corresponding temperature measuring device.
2. The electrically heated semi-coke oven for low-rank pulverized coal dry distillation according to claim 1, characterized in that, Each electric heater consists of a ceramic rod and an electric heating wire wound around the ceramic rod.
3. The electrically heated semi-coke oven for low-rank pulverized coal dry distillation according to claim 1, characterized in that, A refractory material layer is provided between the electric heating chamber and the carbonization chamber.
4. The electrically heated semi-coke oven for low-rank pulverized coal dry distillation according to claim 1, characterized in that, The furnace wall of the semi-coke oven consists of a steel structure shell, a refractory brick wall, and an insulation layer arranged sequentially from the outside to the inside.
5. An electrically heated semi-coke oven for the dry distillation of low-rank pulverized coal according to claim 1, characterized in that, Each carbonization chamber is equipped with a conical hopper at the bottom; the coke discharge system consists of a screw conveyor, a coke discharge bin, and a coke discharge valve. The screw conveyor is located below the conical hopper along the arrangement direction of the conical hoppers. The drive end of the screw conveyor is equipped with a motor. The discharge end of the screw conveyor is connected to the feed inlet at the top of the coke discharge bin. A coke discharge valve is located at the discharge outlet at the bottom of the coke discharge bin.