CN211734263U - Solid heat carrier furnace for solid waste pyrolysis treatment - Google Patents

Solid heat carrier furnace for solid waste pyrolysis treatment Download PDF

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CN211734263U
CN211734263U CN202020112773.XU CN202020112773U CN211734263U CN 211734263 U CN211734263 U CN 211734263U CN 202020112773 U CN202020112773 U CN 202020112773U CN 211734263 U CN211734263 U CN 211734263U
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hearth
heat carrier
solid
solid heat
phase region
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张彦军
宋小飞
许杰
丁建亮
赵恒�
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Beijing Aerospace Petrochemical Technology and Equipment Engineering Corp Ltd
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Beijing Aerospace Petrochemical Technology and Equipment Engineering Corp Ltd
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Abstract

The utility model belongs to the technical field of solid waste pyrolysis, concretely relates to use controllable solid heat carrier heating furnace of many fuel combustion circulation volume. The bottom of the hearth of the solid heat carrier furnace is externally connected with a bottom air chamber, and the end part of the bottom air chamber is connected with a bottom burner; water cooling walls are arranged on four walls of a hearth, the hearth is vertical, a dense phase region of the hearth is arranged at the lower part of the hearth, a dilute phase region is arranged at the upper part of the dense phase region, and side wall burners are arranged on the dense phase region of the hearth, the dilute phase region and the side walls of transition sections of the dense phase region and the dilute phase region of the hearth in a multi-point and layered mode; and after gas-solid mixture in the hearth of the solid heat carrier furnace enters the cyclone separator from the outlet of the hearth and is subjected to gas-solid separation, the high-temperature solid heat carrier enters the pyrolysis equipment from a dipleg at the lower part of the cyclone separator through the blanking controller to complete pyrolysis, and returns to the hearth of the solid heat carrier furnace again through the material returning mechanism along with pyrolysis residues to be heated again, so that circulation is formed. The utility model discloses a single loop type introduces unloading controller and returning charge mechanism in the system, realizes the adjustability of solid heat carrier circulation volume jointly.

Description

Solid heat carrier furnace for solid waste pyrolysis treatment
Technical Field
The utility model belongs to the technical field of solid waste pyrolysis, concretely relates to use controllable solid heat carrier heating furnace of many fuel combustion circulation volume.
Background
In recent years, the pyrolysis technology is utilized to treat solid wastes, and the environment-friendly advantage of no dioxin generation is taken as a new development direction of the solid waste treatment industry. The pyrolysis process is an endothermic process, and the heat source supply mode comprises a solid heat carrier and a gas heat carrier. Among them, the solid heat carrier heating method is widely adopted with the advantages of high heat transfer rate, high heating efficiency, and the like.
The technology of pyrolyzing solid materials by adopting a solid heat carrier method is mainly carried out by coupling an entrained flow bed, a fluidized bed and the like with pyrolysis equipment in China. The solid heat carrier is heated by a circulating fluidized bed boiler, and the heated circulating hot ash and the heated solid heat carrier are used as pyrolysis heat sources, so that the solid material is pyrolyzed, and the advantages of poly-generation of heat, electricity and gas are advocated.
The circulating fluidized bed boiler is a technology of utilizing solid fuel particles to perform combustion after being fluidized by gas in a hearth, and has the advantages of high combustion efficiency, low combustion pollution discharge amount, large load regulation range and the like; however, the traditional boiler also has fixed combustion fuel, mainly takes solid fuel as main fuel, the proportion of other fuel mixed combustion is limited, and the load of the current mixed combustion fuel is generally less than 30%; the circulation quantity is uncontrollable and cannot be adjusted.
Based on the uncontrollable current situation of traditional circulating fluidized bed boiler circulation volume, the solid waste pyrolysis treatment technology adopts two-way material returning mode of an external circulation system. The technology continues to use the principle of a conventional fluidized bed boiler, a bypass is added in an external circulation pipeline, and the circulation quantity is adjusted through a bypass flow dividing structure, so that the adjustment requirement of a heat supply source in the pyrolysis process is met. However, the two-way material return brings with it a complex control system and a greater risk of blockage for solid materials with poor flowability. Therefore, no industrial large-scale application case is developed in the conventional solid material pyrolysis device adopting the process.
In addition, aiming at the solid waste industry, the material components are complex, for example, domestic garbage and the like contain various organic matters and inorganic matters, so that the pyrolysis solid residue components are complex, the particle size, the volume and the shape deviation are large, and the blockage is easy to occur.
Therefore, a solid heat carrier furnace which takes pyrolysis products as fluidized bed boiler fuel, is controllable in circulation quantity, is suitable for a solid heat carrier furnace with complex return material components and large particle size deviation is developed by combining a solid material pyrolysis process, and has great significance for large-scale industrial application of the solid waste pyrolysis industry.
Disclosure of Invention
An object of the utility model is to provide a be applicable to three kinds of fuels of gas, oil, carbon, wherein solid fuel ash content is big, the flash point is high, the heat load is less (< 40%), and the circulation volume is controllable to be applicable to the material returning charge that the component is complicated, the particle diameter deviation is big, but the solid heat carrier heating furnace of industrialization application.
In order to achieve the above purpose, the utility model adopts the technical proposal that:
a solid heat carrier furnace for solid waste pyrolysis treatment is characterized in that the bottom of a hearth of the solid heat carrier furnace is externally connected with a bottom air chamber, and the end part of the bottom air chamber is connected with a bottom burner; water cooling walls are arranged on four walls of the hearth, the hearth is vertical, the lower part of the hearth is a dense-phase region of the hearth, the upper part of the dense-phase region is a dilute-phase region, and a transition section of the dense-phase region and the dilute-phase region is arranged between the dense-phase region and the dilute-phase region. Side wall burners are arranged on the side walls of the dense-phase area and the dilute-phase area of the hearth and the transition section of the dense-phase area and the dilute-phase area of the hearth in a multi-point and layered mode; gas-solid mixture in a hearth of the solid heat carrier furnace enters a cyclone separator from a hearth outlet, after gas-solid separation is carried out, a high-temperature solid heat carrier enters pyrolysis equipment from a dipleg at the lower part of the cyclone separator through a blanking controller to complete pyrolysis, and returns to the hearth of the solid heat carrier furnace again through a material returning mechanism along with pyrolysis residues to be heated again, so that circulation is formed; the separated high-temperature flue gas enters a tail flue from a central cylinder at the upper part of the cyclone separator, a channel 1 is additionally arranged before the flue gas enters the tail flue, and water-cooled walls are arranged on four walls of the channel 1, so that the flue gas firstly flows downwards along the channel 1 to exchange heat with the water-cooled walls, and the flue gas after being cooled flows upwards in a countercurrent manner to exchange heat with a heating surface in the tail flue.
After the gas-solid separation of the high-temperature solid heat carrier is carried out by the cyclone separator, the solid heat carrier adopts a single-loop type and returns to the hearth by a dipleg at the lower part of the cyclone separator through the blanking controller, the pyrolysis equipment and the material returning mechanism.
The bottom burner adopts a fuel oil, fuel gas or fuel oil and fuel gas dual-purpose burner, adopts a single air supply, injection and continuous combustion mode, and has a load regulation range of 20-200%.
The side wall burner adopts a gas, fuel oil or fuel oil and gas dual-purpose burner, adopts a single mode of air supply, fuel injection and continuous combustion respectively, and has a single load regulation range of 20-200%.
The bottom burner and the side wall burner adopt a scheme of continuous combustion above and below the bed.
The feeding controller, the primary air quantity in the hearth of the solid heat carrier furnace and the material returning mechanism jointly control the circulation quantity of the solid heat carrier and realize adjustability so as to adapt to the change of the heat absorption quantity caused by the change of the feeding quantity and the heat value of the solid pyrolysis material and enable pyrolysis products to always meet the heat transfer requirement in the hearth of the solid heat carrier furnace.
The material returning mechanism adopts a mechanical shaftless spiral material returning device, and is suitable for smooth material returning of materials with complex components, large particle size deviation and high strength.
The combination of the channel 1 and the tail flue enables the flue gas to be reversed at 180 degrees in the flowing direction, promotes the sedimentation of dust in the flue gas in a bottom ash bucket, and reduces the fly ash content at the tail of the flue gas.
The utility model discloses the beneficial effect who gains does:
1) the utility model discloses solid heat carrier furnace sets up independent air feed, injection formula oil gas dual-purpose combustor through bed on, under the bed, realizes oil, gas fuel big proportion burning (heat load > 60%) to through the adjustability of combustor, realize that the ash content is big, the burning point is high, the solid fuel's that the heat load is little (< 40%) abundant burning, finally realize oil, gas, solid many combustion stability, continuous combustion.
2) The utility model discloses solid heat carrier furnace external circulation system adopts the single loop type, introduces unloading controller and returning charge mechanism in the system, realizes the adjustability of solid heat carrier circulation volume jointly, makes simple, the easy operation of solid heat carrier circulation volume control system.
3) The utility model discloses solid heat carrier furnace adopts mechanical shaftless spiral returning charge mechanism, changes conventional fluidized bed boiler air feed return valve returning charge pattern, solves the smooth returning charge of the complicated, big, the high strength material of particle diameter deviation of component to realize online, real-time adjustment returning charge volume.
Drawings
Fig. 1 is a schematic view of the solid heat carrier furnace of the present invention.
In the figure: 1. a solid heat carrier furnace hearth; 2. a bottom plenum; 3. a dense-phase region of the hearth; 4. a dilute phase zone of the hearth; 5. a water cooled wall; 6. a bottom burner; 7. a sidewall burner; 8. a cyclone separator; 9. a blanking controller; 10. a pyrolysis device; 11. a material returning mechanism; 12.1 a channel; 13. and a tail flue.
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.
As shown in figure 1, a solid heat carrier furnace for solid waste pyrolysis treatment includes solid heat carrier furnace 1, bottom plenum 2, furnace dense phase zone 3, furnace dilute phase zone 4, water-cooled wall 5, bottom burner 6, side wall burner 7, cyclone 8, unloading controller 9, pyrolysis equipment 10, material returning mechanism 11, 1 passageway 12, afterbody flue 13.
The bottom of the solid heat carrier furnace hearth 1 is externally connected with a bottom air chamber 2, and the end part of the bottom air chamber 2 is connected with a bottom burner 6. The bottom combustor 6 adopts a fuel oil, gas or oil gas dual-purpose combustor, adopts a single air supply, injection and continuous combustion mode, and has a load regulation range of 20-200%. The scheme is different from a conventional fluidized bed boiler bottom burner which is a start-up combustion scheme, the solid fuel continuous operation is long-term, and the fuel quantity entering the burner can be timely adjusted according to the ignition point temperature of the solid fuel, so that the temperature of smoke and air entering an air chamber (the air temperature range is 200-700 ℃) is controlled, and the combustibility of the solid fuel is ensured. The adjustability of the bottom burner 6 and the continuous and independent air distribution combustion scheme can solve the problems of large ash content, high ignition point and non-flammability of the solid fuel, and the temperature of smoke and air generated after combustion is higher than the ignition point of the solid fuel in the dense-phase zone 3 by adjusting the fuel quantity, so that the solid fuel in the furnace can be ensured to be flammable; meanwhile, as the heat load of the solid fuel is small, the temperature of the dense-phase region can be increased after high-temperature flue gas in the air chamber enters the dense-phase region, and the defect that the bed temperature is low due to insufficient heat released by the solid fuel (the heat load is less than 40%) is overcome.
The inner edge of the solid heat carrier furnace hearth 1 is vertical, the lower part is a hearth dense-phase area 3, the upper part of the hearth dense-phase area 3 is a hearth dilute-phase area 4, and a dense-dilute-phase area transition section is arranged between the hearth dense-phase area and the dilute-phase area. The side wall burners 7 are arranged on the side walls of the dense-phase area 3 and the dilute-phase area 4 of the hearth and the transition section of the dense-phase area and the dilute-phase area of the hearth, dual-purpose burners of gas, fuel oil or oil gas are adopted, the burners adopt a multi-point and layered arrangement scheme, each burner adopts a fuel injection and independent air distribution mode, and the load adjustment range of a single burner is 20-200%. Through the multipoint and layered arrangement of the burners, the temperature field in the solid heat carrier hearth 1 is uniform, so that the full combustion of solid fuel and the heating uniformity of the solid heat carrier are ensured. The scheme adopted by the side wall burner is different from the scheme that the conventional fluidized bed boiler directly sprays the mixed fuel into the hearth to be mixed with the secondary air for combustion, so that the scheme adopted at present can ensure the full combustion of the fuel, and effectively solves the problems of deflagration or insufficient combustion and the like caused by uneven mixing after the fuel is sprayed into the hearth and mixed with the secondary air.
The bottom burner 6 and the side wall burner 7 adopt a continuous combustion scheme above and below the bed, so that the fuel of oil and gas can be combusted in a large proportion (the thermal load is more than 60%); and through the adjustability of the combustor, the solid fuel with large ash content, high ignition point and small heat load (< 40%) is fully combusted, and finally, stable and continuous combustion of oil, gas and solid is realized.
Water cooling walls 5 are arranged on four walls inside a hearth 1 of the solid heat carrier furnace, and the combustion scheme enables a stable temperature field to be kept in the hearth, so that the water cooling walls 5 effectively and uniformly transfer heat while uniform heating and circulating heat exchange of the solid heat carrier are realized, and the stable operation of the solid heat carrier furnace is ensured.
The solid heat carrier is heated to 850-950 ℃ in the hearth 1 and enters the cyclone separator 8 along with high-temperature flue gas from the outlet of the hearth. An inlet of the cyclone separator 8 is horizontally connected with an outlet of the solid heat carrier furnace hearth 1, the solid heat carrier is subjected to gas-solid separation through the cyclone separator 8 and then enters the blanking controller 9 through a dipleg at the lower part of the cyclone separator 8, and the separated flue gas enters the tail flue 13 through the central cylinder at the upper part.
The solid heat carrier passes through a lower dipleg of the cyclone separator 8, adopts a single-loop type, falls into the pyrolysis equipment 10 through the blanking controller 9, enters the lower material returning mechanism 11 along with pyrolysis residues after pyrolysis of the solid waste is completed in the pyrolysis equipment, and is sent into the solid heat carrier hearth 1 again through the material returning mechanism 11 to be heated again, and circulation is completed. The single-loop circulation design of the solid heat carrier ensures that the control scheme of the circulation system is simple and easy to operate, and ensures the feasibility of the industrial application of the circulation of the system.
And a dipleg at the lower part of the cyclone separator 8 is connected with an inlet of a blanking controller 9, an outlet of the blanking controller 9 is connected with a pyrolysis device 10, and a solid mixture outlet of the pyrolysis device 10 is connected with a material returning mechanism 11. The inlet of the material returning mechanism 11 is connected with the pyrolysis device 10, and the outlet is connected with the material returning inlet of the solid heat carrier furnace hearth 1.
The material returning mechanism 11 adopts a mechanical shaftless spiral material returning device, the material returning mechanism 11 is different from the conventional fluidized bed boiler in air supply material returning valve type material returning, the conventional material returning valve can avoid the problems of large particle size deviation and easy blockage of massive inorganic matters, and the material returning mechanism is more suitable for smooth material returning of high-strength materials with complex components and large particle size deviation.
The solid heat carrier flow entering the pyrolysis device 10 is adjusted by adjusting the valve opening of the blanking controller 9 so as to adapt to the change of the solid pyrolysis material feeding quantity and the heat value and the change of the caused heat absorption quantity, thereby ensuring that the pyrolysis is sufficient and the pyrolysis product meets the requirement. Meanwhile, the online and real-time adjustment of the return amount is realized by adjusting the primary air quantity in the hearth 1 of the solid heat carrier furnace and the mechanical control frequency of the return mechanism 11, and the adjustability of the circulation amount of the solid heat carrier circulation system is generally realized, so that the pyrolysis product always meets the heat transfer requirement in the hearth 1.
The high-temperature flue gas enters a tail flue 13 from a central cylinder at the upper part of a cyclone separator 8, a channel 1 is additionally arranged before the flue gas enters the tail flue 13, and water-cooled walls 5 are arranged on four walls of the channel 1 12, so that the flue gas firstly flows downwards along the channel 1 along the channel 12 to exchange heat with the water-cooled walls 5, and the flue gas after being cooled flows upwards in a countercurrent manner to exchange heat with a heating surface in the tail flue 13. The structure can adjust the temperature of the flue gas entering the tail flue 13, thereby adjusting the wall temperature of the heat exchange tube, avoiding the high-temperature corrosion of HCL in the flue gas to the tail heating surface and reducing the tube explosion probability of the high-temperature heat exchange tube; but also can prevent the deposition of dust in the flue gas on the wall surface of the pipe, and ensure the heat transfer efficiency and the corrosion of the dust on the heated surface. The combination of the channel 1 and the tail flue 13 makes the flue gas reverse 180 degrees in the flowing direction, promotes the sedimentation of dust in the flue gas in a bottom ash bucket, reduces the fly ash content at the tail of the flue gas, reduces the fly ash treatment cost of the device, and improves the environmental protection index.

Claims (5)

1. The utility model provides a solid heat carrier stove for giving up pyrolysis treatment which characterized in that: the bottom of the hearth of the solid heat carrier furnace is externally connected with a bottom air chamber, and the end part of the bottom air chamber is connected with a bottom burner; water cooling walls are arranged on four walls of the hearth, the hearth is vertical, the lower part of the hearth is a dense-phase region of the hearth, the upper part of the dense-phase region is a dilute-phase region, and a transition section of the dense-phase region and the dilute-phase region is arranged between the dense-phase region and the dilute-phase region; side wall burners are arranged on the side walls of the dense-phase area and the dilute-phase area of the hearth and the transition section of the dense-phase area and the dilute-phase area of the hearth in a multi-point and layered mode; gas-solid mixture in a hearth of the solid heat carrier furnace enters a cyclone separator from a hearth outlet, after gas-solid separation is carried out, a high-temperature solid heat carrier enters pyrolysis equipment from a dipleg at the lower part of the cyclone separator through a blanking controller to complete pyrolysis, and returns to the hearth of the solid heat carrier furnace again through a material returning mechanism along with pyrolysis residues to be heated again, so that circulation is formed; the separated high-temperature flue gas enters a tail flue from a central cylinder at the upper part of the cyclone separator, a channel 1 is additionally arranged before the flue gas enters the tail flue, and water-cooled walls are arranged on four walls of the channel 1, so that the flue gas firstly flows downwards along the channel 1 to exchange heat with the water-cooled walls, and the flue gas after being cooled flows upwards in a countercurrent manner to exchange heat with a heating surface in the tail flue.
2. The solid heat carrier furnace for solid waste pyrolysis treatment according to claim 1, characterized in that: the bottom burner adopts a fuel oil, fuel gas or fuel oil and fuel gas dual-purpose burner, adopts a single air supply, injection and continuous combustion mode, and has a load regulation range of 20-200%.
3. The solid heat carrier furnace for solid waste pyrolysis treatment according to claim 1, characterized in that: the side wall burner adopts a gas, fuel oil or fuel oil and gas dual-purpose burner, adopts a single mode of air supply, fuel injection and continuous combustion respectively, and has a single load regulation range of 20-200%.
4. The solid heat carrier furnace for solid waste pyrolysis treatment according to claim 1, characterized in that: the bottom burner and the side wall burner adopt a scheme of continuous combustion above and below the bed.
5. The solid heat carrier furnace for solid waste pyrolysis treatment according to claim 1, characterized in that: the material returning mechanism adopts a mechanical shaftless spiral material returning device.
CN202020112773.XU 2020-01-17 2020-01-17 Solid heat carrier furnace for solid waste pyrolysis treatment Active CN211734263U (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113136224A (en) * 2020-01-17 2021-07-20 北京航天石化技术装备工程有限公司 Solid heat carrier furnace for solid waste pyrolysis treatment
CN116515511A (en) * 2023-05-06 2023-08-01 西安交通大学 Biomass gasification comprehensive utilization system

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113136224A (en) * 2020-01-17 2021-07-20 北京航天石化技术装备工程有限公司 Solid heat carrier furnace for solid waste pyrolysis treatment
CN116515511A (en) * 2023-05-06 2023-08-01 西安交通大学 Biomass gasification comprehensive utilization system
CN116515511B (en) * 2023-05-06 2024-03-12 西安交通大学 Biomass gasification comprehensive utilization system

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