CN107022363A - A kind of continuous biomass pyrolysis gas is reversely flowd back towards with charcoal gas cogeneration facility - Google Patents

Abstract

The invention discloses a continuous charcoal gas cogeneration equipment for countercurrent recycling of biomass pyrolysis gas. It consists of a pyrolysis gas heat exchange device, a pyrolysis device, a pyrolysis gas recovery system and a start-up heat source. Inside the pyrolysis device, the countercurrent heat exchange between the high-temperature pyrolysis gas and the biomass raw material provides an internal heat source for biomass pyrolysis, and through the partial combustion of the biomass pyrolysis gas, it not only provides a heat source for the high-temperature cracking of the remaining pyrolysis gas, Moreover, an external heat source is provided for the continuous pyrolysis of the front-end biomass, and the combined internal and external heating enables efficient energy recovery and utilization. At the same time, after the pyrolysis gas is detarred by high-temperature cracking, the heat is transferred to the circulating water through the coil heat exchanger for heating, and the collection of pure pyrolysis gas and biochar is realized at the end.

Description

A continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment

technical field

The invention belongs to the technical field of renewable energy, and specifically relates to a continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment, which is suitable for pyrolysis of various biomass under different conditions. During work, it can not only realize pyrolysis The continuous pyrolysis of the biomass raw material of the furnace, and the partial combustion of the pyrolysis gas is completed to provide the pyrolysis heat source, the secondary catalytic cracking of the tar and the waste heat recovery of the cracking gas.

Background technique

Biochar is a solid product produced by thermal cracking of biomass organic materials in an anoxic or anaerobic environment. It is rich in resources and has a wide range of uses. It can be used not only as a high-quality energy source, but also as a reducing agent, as well as a soil improver, fertilizer slow-release carrier and carbon dioxide sequestration agent.

At present, due to the emphasis on the study of biomass pyrolysis mechanism, some remarkable results have been produced. Pyrolysis equipment can be divided into batch type and continuous type according to the production mode. Among them, heat pipe type and fixed bed type pyrolysis equipment belong to batch type, while rotary furnace type and spiral type belong to continuous type. Although the heat pipe fixed-bed biomass pyrolysis test bench can flexibly explore the laws of pyrolysis factors such as heating rate, final pyrolysis temperature, residence time, and reaction pressure, it can only operate intermittently, so it is limited to a certain extent. Its industrial promotion. The continuous pyrolysis test bench can make up for this deficiency and realize continuous biomass pyrolysis. However, the existing continuous pyrolysis test benches have certain problems in heat source supply and tar removal. Most heat sources are provided by burning biomass raw materials, which not only leads to unstable heat source temperature, but also causes environmental pollution. Electric heating Or the combustion of natural gas will waste secondary energy, resulting in an increase in the cost of carbon production; and the methods of tar removal include physical methods such as cyclones, condensation filtration, and electric tar collectors, and chemical methods such as high-temperature cracking and catalytic cracking, among which physical methods cannot be used. It is not widely used to get rid of tar from the source, and chemical methods such as pyrolysis and catalytic cracking have high temperature requirements and are difficult to achieve. The present invention uses part of the pyrolysis gas to recycle and burn, to provide heat sources for high-temperature cracking and continuous pyrolysis in sequence, and the other part of the pyrolysis gas reaches a higher tar removal rate after high-temperature cracking, and then conducts heat exchange, condensation, collection and separation, and realizes Cogeneration of carbon and gas from biomass pyrolysis.

Contents of the invention

The purpose of the present invention is to solve the problems of unstable heat source and difficulty in tar removal in the existing biomass pyrolysis technology described in the technical background, and disclose a continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment. It is characterized in that the equipment mainly includes a feeding device (1), a pyrolysis device (2), a biochar water cooling device (3), a flue gas post-processing device (4), a pyrolysis gas purification and separation device (5), a thermal Composed of pyrolysis gas heat exchange device (6), high temperature cracking device (7), pyrolysis gas recovery system (8) and starting heat source (9), the feeding device (1) is connected to the pyrolysis device through the air shutoff device (2) (2), the rear end of the pyrolysis device (2) is connected to the biochar water cooling device (3), and the front end is connected to the pyrolysis device (7) by a metal filter screen (111), and the pyrolysis gas outlet (702) of the pyrolysis device (7) ) is connected to the pyrolysis gas heat exchange device (6), the rear end of the pyrolysis gas heat exchange device (6) is connected to the pyrolysis gas purification and separation device (5), and the flue gas outlet (701) of the pyrolysis device (7) is connected to the thermal The pyrolysis gas recovery system (8), the pyrolysis gas recovery system (8) and the start-up heat source (9) are connected in parallel at the high-temperature flue gas inlet port (107). The whole operation process is to start the heat source (9) to provide heat for the pyrolysis device (2) by burning natural gas, and the biochar produced in the pyrolysis device (2) is cooled by the biochar water cooling device (3) and falls into the carbon collection box In (307), the pyrolysis gas produced by the pyrolysis device (2) is divided into two paths, one path of pyrolysis gas passes through the high temperature cracking device (7) to remove tar and then is collected into the gas cabinet (504) after heat exchange cooling and cooling separation ), the other pyrolysis gas is combusted by the pyrolysis device (7) to provide a heat source for pyrolysis and continuous pyrolysis, and then it is purified by the spray tower (4) and then emptied.

The continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment is characterized in that the pyrolysis gas outlet (112) is set at one end of the pyrolysis reaction chamber (3) feeding, and the material moving direction On the contrary, a metal filter screen (111) is installed between the pyrolysis gas outlet (112) and the gas pipeline (707). In this way, the high-temperature pyrolysis gas and the biomass raw material form a countercurrent heat exchange, which increases the utilization rate of the heat of the pyrolysis gas.

A kind of continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment is characterized in that the high temperature cracking device (7) is mainly composed of an insulating layer (703), a spiral pipe (704), a pyrolysis gas combustion chamber ( 708), pyrolysis gas burner (709) distribution pipe (711), pyrolysis gas cracking valve (705) and pyrolysis gas combustion valve (706). The pyrolysis device (7) adopts a simple combustion furnace design method, and uses the heat generated by the combustion of the pyrolysis gas itself to calcinate another part of the pyrolysis gas to achieve the purpose of removing tar.

The continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment is characterized in that the pyrolysis gas outlet (112) is divided into two paths connected to the high-temperature cracking device (7), and one path is connected to the pyrolysis gas cracking valve (705), the other road is connected to the pyrolysis gas combustion valve (706), and the opening degrees of the two valves are adjustable. The adjustment of the pyrolysis gas combustion valve (706) is required to ensure the minimum amount of pyrolysis gas combustion required for normal operation of pyrolysis and biomass pyrolysis.

The continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment is characterized in that the pyrolysis gas cracking valve (705) is connected to the spiral pipe (704) in the high temperature cracking device (7), and the pyrolysis gas The combustion valve (706) is installed at the bottom of the spiral pipe (704), and communicates with the pyrolysis gas burner (709) and the gas distribution pipe (711). The air compressor (713) at the lower end of the pyrolysis device (7) provides stable air for the combustion of the pyrolysis gas in the furnace, and the gas burner one (709) ensures a stable flame in the furnace through the gas bottle one (712), so as to Ensure that the pyrolysis gas is fully combusted.

The continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment is characterized in that the pyrolysis gas recovery system (8) is mainly composed of a pyrolysis gas recycling pipeline (801), a pyrolysis gas pipeline valve (802), a pyrolysis device sleeve (105), a baffle (106), a high-temperature flue gas inlet (107) and a high-temperature flue gas outlet (109), and the high-temperature flue gas inlet (107) is located at the carbon outlet end, The high-temperature flue gas outlet (109) is arranged at the feed end. The high-temperature flue gas generated by pyrolysis gas combustion passes through the pyrolysis device (7) and then enters the pyrolysis device sleeve (105). The direction of the flue gas is opposite to the direction of material movement, and the sleeve is equipped with a baffle (106). , increasing the gas residence time, which is conducive to the heat exchange and temperature rise of biomass raw materials.

The continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment is characterized in that the pyrolysis gas heat exchange device (6) mainly consists of a high-temperature cracking gas inlet (604), a spiral coil (601), The heat exchange tank (602), the circulating water inlet (605) and the circulating water outlet (603) are composed, the circulating water inlet (605) is connected to the bottom of the heat exchange tank (602), and the circulating water outlet (603) is connected to the heat exchange Water tank (602) top.

The continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment is characterized in that the start-up heat source (9) is mainly composed of gas pipeline valve two (901), gas burner two (902), gas valve ( 903) and a gas bottle (904) are formed, and natural gas is filled in the gas bottle two (904). Before the operation of the equipment, the starting heat source is turned on to supply heat for the equipment, and the gas pipeline valve (901) is closed after the operation of the equipment starts, and the equipment starts to operate normally.

Specifically, the invention patent has the following advantages compared with the prior art:

1) A kind of continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment in the present invention adopts the high temperature pyrolysis gas generated in the pyrolysis device and the high temperature flue gas produced by pyrolysis gas combustion at the same time countercurrent reheating, The internal and external combined heating makes the biomass raw material heated more evenly and improves the heat exchange coefficient.

2) The high-temperature cracking device in the present invention adopts the principle of flame calcination, and the high-temperature heat generated by directly burning the pyrolysis gas with an open flame performs high-temperature cracking on the remaining pyrolysis gas to achieve the purpose of cracking tar.

3) The pyrolysis gas reuse in the present invention provides heat source for the high-temperature cracking of the rest of the pyrolysis gas and the pyrolysis of the whole biomass through partial combustion of the pyrolysis gas, and realizes efficient recovery and utilization of energy.

4) The waste heat recovery system in the present invention, through the sufficient heat exchange between the spiral tube and the circulating water in the water tank, not only cools down the pyrolysis gas, but also raises the water temperature for heating.

Description of drawings

Fig. 1 is a kind of continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment structural schematic diagram;

Fig. 2 is a schematic diagram of a continuous pyrolysis device;

Fig. 3 is a schematic diagram of a pyrolysis device;

Fig. 4 is a schematic diagram of a pyrolysis gas combustion recycling system;

Fig. 5 is a schematic diagram of a high-temperature cracked gas waste heat recovery system;

Figure 6 is a schematic diagram of biochar circulating water cooling.

In the figure, 1--feeding device, 2--pyrolysis device, 3--biochar water cooling device, 4--flue gas post-processing device, 5-pyrolysis gas purification and separation device, 6--pyrolysis gas exchange Thermal device, 7--high-temperature cracking device, 8--pyrolysis gas recovery system, 9--starting heat source, 101--hopper, 102--air shutoff device, 103--pyrolysis chamber, 104--screwing Long, 105—pyrolysis device sleeve, 106—baffle plate, 107—high temperature flue gas inlet, 108—charcoal outlet, 109—high temperature flue gas outlet, 110—inverter motor, 111—metal filter Net, 112—pyrolysis gas outlet, 301—biochar inlet, 302—screw auger 2, 303—sleeve, 304—charcoal heat exchange outlet, 305—frequency conversion motor 2, 306—gate valve, 307—char collection Warehouse, 308--charcoal heat exchange water inlet, 501-three-phase separator, 502-water storage tank, 503-oil storage tank, 504-gas cabinet, 505-induced fan 2, 506-gas flow meter, 601-spiral Coil, 602—heat exchange tank, 603—circulating water outlet, 604—high temperature pyrolysis gas inlet, 605—circulating water inlet, 701—pyrolysis gas outlet, 702—pyrolysis gas outlet, 703—insulation layer, 704— Spiral pipe, 705—pyrolysis gas cracking valve, 706—pyrolysis gas combustion valve, 707—gas pipeline, 708—pyrolysis gas combustion chamber, 709—pyrolysis gas burner, 710—gas pipeline, 711—gas distribution pipe, 712—gas pipeline valve 1, 713—gas bottle, 714—air compressor, 715—gas distribution valve, 801—pyrolysis gas recycling pipeline, 802—pyrolysis gas pipeline valve, 901—gas pipeline valve 2, 902— Gas burner two, 903—gas valve, 904—gas bottle two.

detailed description

The specific structure and working process of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1, a continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment structure schematic diagram, the equipment mainly includes a feed device (1), a pyrolysis device (2), a biochar water cooling device (3 ), flue gas post-processing device (4), pyrolysis gas purification and separation device (5), pyrolysis gas heat exchange device (6), high temperature cracking device (7), pyrolysis gas recovery system (8) and starting heat source (9), characterized in that the feeding device (1) is connected to the pyrolysis device (2) through the air shutoff device (2), the rear end of the pyrolysis device (2) is connected to the biochar water cooling device (3), and the front end passes through the pyrolysis device. The gas outlet (112) is connected to the pyrolysis device (7), and the pyrolysis gas outlet (702) of the pyrolysis device (7) is connected to the pyrolysis gas heat exchange device (6), and the rear end of the pyrolysis gas heat exchange device (6) is connected The thermal cracking gas purification and separation device (5), the flue gas outlet (701) of the pyrolysis device (7) is connected to the thermal cracking gas recovery system (8), and the thermal cracking gas recovery system (8) and the start-up heat source (9) are connected in parallel At the high temperature flue gas inlet port (107). The whole operation process is to start the heat source (9) to provide heat for the pyrolysis device (2) by burning natural gas, and the biochar produced in the pyrolysis device (2) is cooled by the biochar water cooling device (3) and falls into the charcoal collection bin In (307), the pyrolysis gas produced by the pyrolysis device (2) is divided into two paths, one path of pyrolysis gas passes through the high temperature cracking device (7) to remove tar and then is collected into the gas cabinet (504) after heat exchange cooling and cooling separation ), the other pyrolysis gas is combusted by the pyrolysis device (7) to provide a heat source for pyrolysis and continuous pyrolysis, and then it is purified by the flue gas post-processing device (4) and then emptied.

As shown in the continuous pyrolysis device schematic diagram of Figure 2, the rotating speed of the air shutoff device (102) controls the processing capacity per hour, and the screw auger (104) is used to continuously transport materials, and the pyrolysis gas outlet (112) is located at the inlet Material end, in order to achieve the purpose of countercurrent reheating of pyrolysis gas.

As shown in the schematic diagram of the pyrolysis device in Figure 3, the pyrolysis gas is divided into two paths, one path enters the pyrolysis gas combustion chamber (708) for combustion to provide a heat source, and the other path enters the spiral tube (704) for pyrolysis of tar.

As shown in the schematic diagram of the pyrolysis gas combustion recycling system shown in Figure 4, the gas burner 2 (902) passes the high-temperature flue gas generated by natural gas combustion into the pyrolysis device sleeve (105) to provide a starting heat source for biomass pyrolysis After the device is in normal operation, the generated pyrolysis gas is burned to generate heat through the pyrolysis gas recycling pipeline (801) to provide heat for pyrolysis, and then it is emptied after being cleaned by the flue gas post-processing device (4).

As shown in the schematic diagram of high-temperature pyrolysis gas waste heat recovery system in Figure 5, the pyrolysis gas after high-temperature pyrolysis exchanges heat with circulating water during the passage of the spiral coil (601), and transfers excess heat to water for heating. In order to prevent the presence of tar, the cooled gas is re-passed into the three-phase separator for three-phase separation of oil, water and gas.

As shown in the schematic diagram of biochar circulating water cooling in Figure 6, the biochar after complete pyrolysis and carbonization has a relatively high temperature. Cooling, heat exchange and cooling of high-temperature biochar.

According to above classification, the present invention is described as follows in conjunction with illustration:

Example: Production of biochar and biogas using corn stalks

Using a continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment of the present invention to produce biochar and pyrolysis gas, the raw material is corn stalks, the length is about 3-4mm, the moisture content is 10-20%, and the density is about 100kg /m ³ , first open the natural gas valve, turn on the gas burner to heat the equipment, when the temperature of the equipment reaches the set temperature, generally around 500°C, open the air switch to start feeding, pyrolysis reaction occurs during the movement of the material, The generated biochar is cooled by circulating water and collected into the charcoal collection bin. The generated pyrolysis gas is led by the induced draft fan to feed one end and enters the pyrolysis gas pipeline through the filter. The pipeline is connected with two branches, one for direct combustion Provide heat for pyrolysis and biomass pyrolysis, and another path for high-temperature pyrolysis to remove tar, then heat exchange for heating, and finally condensed, separated and collected. When the equipment is in normal operation, close the natural gas supply valve to realize the co-production of pyrolysis gas self-combustion heating and charcoal gas.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention without limitation. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be Modifications or equivalent replacements without departing from the spirit and scope of the technical solutions of the present invention shall be covered by the claims of the present invention.

Claims (8)

1. A continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment, mainly including a feed device (1), a pyrolysis device (2), a biochar water cooling device (3), and a flue gas post-processing device ( 4), composed of pyrolysis gas purification and separation device (5), pyrolysis gas heat exchange device (6), high temperature cracking device (7), pyrolysis gas recovery system (8) and starting heat source (9), characterized in that The feeding device (1) is connected to the pyrolysis device (2) through the air shutoff device (2), the rear end of the pyrolysis device (2) is connected to the biochar water cooling device (3), and the front end is connected to the pyrolysis device through a metal filter screen (111). Device (7), the pyrolysis gas outlet (702) of the pyrolysis device (7) is connected to the pyrolysis gas heat exchange device (6), and the rear end of the pyrolysis gas heat exchange device (6) is connected to the pyrolysis gas purification and separation device (5 ), the flue gas outlet (701) of the pyrolysis device (7) is connected to the pyrolysis gas recovery system (8), and the pyrolysis gas recovery system (8) and the starting heat source (9) are connected in parallel at the high temperature flue gas inlet port (107 ). 2. A kind of continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment according to claim 1, characterized in that the pyrolysis gas outlet (112) is set at the feed point of the pyrolysis reaction chamber (3) At one end, opposite to the moving direction of the material, a metal filter (111) is installed between the pyrolysis gas outlet (112) and the gas pipeline (707). 3. A kind of continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment according to claim 1, characterized in that the high temperature cracking device (7) is mainly composed of insulation layer (703), spiral pipe (704), The pyrolysis gas combustion chamber (708), the pyrolysis gas burner (709) gas distribution pipe (711), the pyrolysis gas cracking valve (705) and the pyrolysis gas combustion valve (706) are composed. 4. A continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration device according to claim 1 or 3, characterized in that the pyrolysis gas outlet (112) is divided into two paths connected to the pyrolysis device (7) One path is connected to the pyrolysis gas cracking valve (705), and the other path is connected to the pyrolysis gas combustion valve (706). The openings of the two valves can be adjusted. 5. A continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration device according to claim 1, 3 or 4, characterized in that the pyrolysis gas cracking valve (705) is connected to the pyrolysis device (7) The spiral pipe (704), the pyrolysis gas combustion valve (706) is installed in the bottom of the spiral pipe (704), and communicates with the pyrolysis gas burner (709) and the gas distribution pipe (711). 6. A continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration device according to claim 1, characterized in that the pyrolysis gas recovery system (8) is mainly composed of pyrolysis gas recycling pipelines (801) , pyrolysis gas pipeline valve (802), pyrolysis device sleeve (105), baffle plate (106), high temperature flue gas inlet (107) and high temperature flue gas outlet (109), high temperature flue gas inlet (107) It is arranged at the carbon outlet end, and the high-temperature flue gas outlet (109) is arranged at the feed end. 7. A kind of continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment according to claim 1, characterized in that the pyrolysis gas heat exchange device (6) mainly consists of a high temperature cracking gas inlet (604), a spiral coil (601), heat exchange tank (602), circulating water inlet (605) and circulating water outlet (603), the circulating water inlet (605) is connected to the bottom of the heat exchange tank (602), and the circulating water outlet ( 603) is connected to the top of the heat exchange tank (602). 8. A kind of continuous biomass pyrolysis gas countercurrent recycling charcoal gas cogeneration equipment according to claim 1, characterized in that the starting heat source (9) is mainly composed of gas pipeline valve two (901), gas burner two ( 902), gas valve (903) and gas bottle two (904) form, filling natural gas in the gas bottle (904).