阅读说明：本技术 生物质热解系统及其工作方法 (Biomass pyrolysis system and working method thereof ) 是由 马正民 孔德柱 马政峰 于力 白秀军 李小明 赵鹏声 于 2020-05-26 设计创作，主要内容包括：本发明提供了一种生物质热解系统及其工作方法,该生物质热解系统包括：生物质干燥管、载体加热管、热解反应器、第一旋风分离器、第二旋风分离器、余热锅炉、生物油喷淋塔和油气热风炉；生物质干燥管的出气端与第一旋风分离器连接,生物质干燥管的进气端与余热锅炉中烟气的出气端连接,生物质干燥管内容纳有生物质,余热锅炉排出的烟气用于对生物质干燥管内的生物质进行干燥；余热锅炉中烟气的进气端和载体加热管的上端连接,余热锅炉用于吸收由载体加热管输送的热烟气的热量,以产生蒸汽,同时降温后的热烟气由余热锅炉输送至生物质干燥管的进气端。本发明的方案能够提高热解系统的热利用率。(The invention provides a biomass pyrolysis system and a working method thereof, wherein the biomass pyrolysis system comprises: the system comprises a biomass drying pipe, a carrier heating pipe, a pyrolysis reactor, a first cyclone separator, a second cyclone separator, a waste heat boiler, a biological oil spray tower and an oil gas hot blast stove; the gas outlet end of the biomass drying pipe is connected with the first cyclone separator, the gas inlet end of the biomass drying pipe is connected with the gas outlet end of flue gas in the waste heat boiler, biomass is contained in the biomass drying pipe, and the flue gas discharged by the waste heat boiler is used for drying the biomass in the biomass drying pipe; the gas inlet end of the flue gas in the waste heat boiler is connected with the upper end of the carrier heating pipe, the waste heat boiler is used for absorbing the heat of the hot flue gas conveyed by the carrier heating pipe so as to generate steam, and meanwhile, the cooled hot flue gas is conveyed to the gas inlet end of the biomass drying pipe by the waste heat boiler. The scheme of the invention can improve the heat utilization rate of the pyrolysis system.)

1. A biomass pyrolysis system, comprising: the system comprises a biomass drying pipe (101), a carrier heating pipe (102), a pyrolysis reactor (103), a first cyclone separator (104), a second cyclone separator (105), a waste heat boiler (106), a biological oil spray tower (107) and an oil gas hot blast stove (108);

the gas outlet end of the biomass drying pipe (101) is connected with the first cyclone separator (104), the gas inlet end of the biomass drying pipe (101) is connected with the gas outlet end of flue gas in the waste heat boiler (106), biomass is contained in the biomass drying pipe (101), and the flue gas discharged by the waste heat boiler (106) is used for drying the biomass in the biomass drying pipe (101);

the first cyclone separator (104) is connected with the pyrolysis reactor (103) through a biomass bin (109), the first cyclone separator (104) is used for separating biomass and flue gas conveyed by the biomass drying pipe (101), the separated flue gas is discharged through a dust remover (110), the separated biomass is conveyed to the biomass bin (109), and the biomass in the biomass bin (109) is conveyed to the pyrolysis reactor (103) for pyrolysis;

the upper end of the carrier heating pipe (102) is connected with the pyrolysis reactor (103) through a carrier buffer bin (111), a carrier is contained in the carrier heating pipe (102), the carrier is heated in the carrier heating pipe (102) and then conveyed to the carrier buffer bin (111), and the carrier in the carrier buffer bin (111) is conveyed to the pyrolysis reactor (103);

the lower end of the carrier heating pipe (102) is connected with the pyrolysis reactor (103) through a solid-solid separator (112), the solid-solid separator (112) is used for separating a carrier and biochar generated by pyrolysis of the pyrolysis reactor (103), and the separated carrier enters the carrier heating pipe (102);

the inlet end of the second cyclone separator (105) is connected with the upper end of the pyrolysis reactor (103), the first outlet end of the second cyclone separator (105) is connected with a charcoal bin (113), the second outlet end of the second cyclone separator (105) is connected with the bio-oil spray tower (107), and the bio-oil spray tower (107) is used for converting the first bio-gas conveyed by the second cyclone separator (105) into bio-oil and second bio-gas;

the oil-gas hot blast stove (108) is connected with the lower end of the carrier heating pipe (102), at least part of the bio-oil and at least part of the second biogas generated by the bio-oil spray tower (107) are introduced into the oil-gas hot blast stove (108) to be combusted, and the oil-gas hot blast stove (108) is used for heating the carrier in the carrier heating pipe (102) through the generated hot flue gas;

the gas inlet end of flue gas in the waste heat boiler (106) is connected with the upper end of the carrier heating pipe (102), the waste heat boiler (106) is used for absorbing heat of hot flue gas conveyed by the carrier heating pipe (102) to generate steam, and meanwhile, the cooled hot flue gas is conveyed to the gas inlet end of the biomass drying pipe (101) by the waste heat boiler (106).

2. The biomass pyrolysis system of claim 1, further comprising: a fluidized bed (114);

the fluidized bed (114) is connected with the waste heat boiler (106), one path of hot flue gas conveyed by the carrier heating pipe (102) is introduced into the fluidized bed (114), the other path of hot flue gas is introduced into a pipeline (115) connected between the fluidized bed (114) and the waste heat boiler (106), and an SNCR ammonia spraying position is arranged on the pipeline (115) connected between the fluidized bed (114) and the waste heat boiler (106);

the fluidized bed (114) is also respectively connected with the solid separator (112), the biochar bin (113) and the bio-oil spray tower (107), and biochar separated by the solid separator (112), biochar stored in the biochar bin (113) and at least part of second biogas discharged by the bio-oil spray tower (107) enter the fluidized bed (114) to be combusted.

3. The biomass pyrolysis system of claim 1, wherein the bio-oil spray tower (107) is connected with a bio-oil bin (116) for storing bio-oil, and a first heat exchanger (117) is connected between the bio-oil bin (116) and the bio-oil spray tower (107);

the biological oil in the biological oil bin (116) enters the biological oil spray tower (107) after being cooled by the first heat exchanger (117) so as to cool a part of condensable parts in the first biological gas and form the biological oil.

4. The biomass pyrolysis system of claim 3, further comprising: a pyroligneous liquor spray tower (118);

the wood vinegar spraying tower (118) is connected with a wood vinegar bin (119) for storing wood vinegar, and a second heat exchanger (120) is connected between the wood vinegar bin (119) and the wood vinegar spraying tower (118);

and the wood vinegar in the wood vinegar liquid bin (119) is cooled by the second heat exchanger (120) and then enters the wood vinegar liquid spray tower (118) so as to cool the condensable part in the second biogas and form wood vinegar liquid.

5. The biomass pyrolysis system of claim 4, further comprising: an electrical tar precipitator (121);

the electrical tar precipitator (121) is connected with the pyroligneous liquor spraying tower (118), and the electrical tar precipitator (121) is used for removing tar and moisture in the non-condensable part of the second biogas discharged from the pyroligneous liquor spraying tower (118).

6. The biomass pyrolysis system of claim 5, further comprising: a combustion engine power generation device (122);

the gas turbine power generation device (122) is respectively connected with the electrical tar precipitator (121) and the waste heat boiler (106), the non-condensable part of the second biogas after tar removal by the electrical tar precipitator (121) forms combustible gas, the combustible gas enters the gas turbine power generation device (122) to be combusted and generated, and tail gas generated by the gas turbine power generation device (122) enters the waste heat boiler (106).

7. The working method of the biomass pyrolysis system according to any one of claims 1 to 6, comprising:

drying the biomass in the biomass drying pipe (101) by using the flue gas discharged by the waste heat boiler (106);

separating the biomass and the flue gas conveyed by the biomass drying pipe (101) by using the first cyclone separator (104), discharging the separated flue gas through a dust remover (110), and conveying the separated biomass to the biomass bin (109);

heating the carrier in the carrier heating pipe (102) by using hot flue gas generated by the oil-gas hot blast stove (108);

pyrolyzing the biomass transported from the biomass silo (109) to the pyrolysis reactor (103) using the heated carriers;

separating the carrier and the biochar generated by pyrolysis in the pyrolysis reactor (103) by using the solid-solid separator (112), wherein the separated carrier enters the carrier heating pipe (102);

separating biochar and first biogas by using the second cyclone separator (105), and converting the first biogas conveyed by the second cyclone separator (105) into bio-oil and second biogas by using the bio-oil spray tower (107);

at least part of the bio-oil and at least part of the second biogas generated by the bio-oil spray tower (107) are introduced into the oil-gas hot blast stove (108) for combustion;

the waste heat boiler (106) is used for absorbing heat of hot flue gas conveyed by the carrier heating pipe (102) to generate steam, and meanwhile, the cooled hot flue gas is conveyed to the air inlet end of the biomass drying pipe (101) by the waste heat boiler (106).

8. The method of operating a biomass pyrolysis system of claim 7, further comprising:

one path of hot flue gas conveyed by the carrier heating pipe (102) is introduced into a fluidized bed (114), and the other path of hot flue gas is introduced into a pipeline (115) connected between the fluidized bed (114) and the waste heat boiler (106);

and (3) introducing the biochar separated by the solid-solid separator (112), the biochar stored in the biochar bin (113) and at least part of second biogas discharged from the bio-oil spray tower (107) into the fluidized bed (114) for combustion.

Technical Field

The invention relates to the technical field of biomass pyrolysis, in particular to a biomass pyrolysis system and a working method thereof.

Background

Biomass refers to various organisms formed by photosynthesis, including all animals and plants and microorganisms. At present, biomass utilization mainly refers to various agricultural and forestry wastes such as straws, sawdust, rice hulls and the like. The main approaches of biomass include straw composting and returning to fields, utilization of industrial straw raw materials, utilization of straw feed and utilization of straw energy, wherein the advantages of high utilization efficiency, good benefit and the like of straw energy are widely regarded and researched. The biomass pyrolysis treatment technology is a thermal cracking method for straw raw materials through a high-efficiency pyrolysis device under the reaction conditions of oxygen deficiency and high temperature to produce products such as bio-combustible gas, bio-oil, bio-charcoal and the like, and the products are wide in utilization, high in additional value and good in benefit compared with the traditional direct incineration treatment.

However, the existing biomass pyrolysis system has at least the following defects: the flue gas that produces after the flue gas that carries out the drying to the biomass usually adopts the heating carrier, but because the temperature of this flue gas is higher (there is about 500 ℃), in order to avoid the biomass by high temperature flue gas carbomorphism, need make this high temperature flue gas collocation cold wind cooling back, again dry the biomass, so reduced pyrolysis system's heat utilization ratio.

Disclosure of Invention

The embodiment of the invention provides a biomass pyrolysis system and a working method thereof, which can improve the heat utilization rate of the pyrolysis system.

In a first aspect, an embodiment of the present invention provides a biomass pyrolysis system, including: the system comprises a biomass drying pipe, a carrier heating pipe, a pyrolysis reactor, a first cyclone separator, a second cyclone separator, a waste heat boiler, a biological oil spray tower and an oil gas hot blast stove;

the gas outlet end of the biomass drying pipe is connected with the first cyclone separator, the gas inlet end of the biomass drying pipe is connected with the gas outlet end of the flue gas in the waste heat boiler, biomass is contained in the biomass drying pipe, and the flue gas discharged by the waste heat boiler is used for drying the biomass in the biomass drying pipe;

the first cyclone separator is connected with the pyrolysis reactor through a biomass bin, the first cyclone separator is used for separating biomass and flue gas conveyed by the biomass drying pipe, the separated flue gas is discharged through a dust remover, the separated biomass is conveyed to the biomass bin, and the biomass in the biomass bin is conveyed to the pyrolysis reactor for pyrolysis;

the upper end of the carrier heating pipe is connected with the pyrolysis reactor through a carrier cache bin, a carrier is contained in the carrier heating pipe, the carrier is heated in the carrier heating pipe and then conveyed to the carrier cache bin, and the carrier in the carrier cache bin is conveyed to the pyrolysis reactor;

the lower end of the carrier heating pipe is connected with the pyrolysis reactor through a solid-solid separator, the solid-solid separator is used for separating a carrier and biochar generated by pyrolysis of the pyrolysis reactor, and the separated carrier enters the carrier heating pipe;

the inlet end of the second cyclone separator is connected with the upper end of the pyrolysis reactor, the first outlet end of the second cyclone separator is connected with a charcoal bin, the second outlet end of the second cyclone separator is connected with the bio-oil spray tower, and the bio-oil spray tower is used for converting the first biogas conveyed by the second cyclone separator into bio-oil and second biogas;

the oil-gas hot-blast stove is connected with the lower end of the carrier heating pipe, at least part of biological oil and at least part of second biogas generated by the biological oil spray tower are introduced into the oil-gas hot-blast stove for combustion, and the oil-gas hot-blast stove is used for heating the carrier in the carrier heating pipe through the generated hot flue gas;

the gas inlet end of flue gas in the exhaust-heat boiler with the upper end of carrier heating pipe is connected, the exhaust-heat boiler is used for absorbing by the heat of the hot flue gas of carrier heating pipe transport to produce steam, the hot flue gas after the while cooling by exhaust-heat boiler carries extremely the gas inlet end of biomass drying tube.

In one possible design, further comprising: a fluidized bed;

the fluidized bed is connected with the waste heat boiler, one path of hot flue gas conveyed by the carrier heating pipe is introduced into the fluidized bed, the other path of hot flue gas is introduced into a pipeline connected between the fluidized bed and the waste heat boiler, and an SNCR ammonia spraying position is arranged on the pipeline connected between the fluidized bed and the waste heat boiler;

the fluidized bed is also respectively connected with the solid-solid separator, the biological carbon bin and the biological oil spray tower, and the biological carbon separated by the solid-solid separator, the biological carbon stored in the biological carbon bin and at least part of second biogas discharged by the biological oil spray tower enter the fluidized bed to be combusted.

In one possible design, the biological oil spray tower is connected with a biological oil bin for storing biological oil, and a first heat exchanger is connected between the biological oil bin and the biological oil spray tower;

and the biological oil in the biological oil bin enters the biological oil spray tower after being cooled by the first heat exchanger so as to cool a part of condensable parts in the first biological gas and form the biological oil.

In one possible design, further comprising: a pyroligneous liquor spray tower;

the wood vinegar spraying tower is connected with a wood vinegar bin for storing wood vinegar, and a second heat exchanger is connected between the wood vinegar bin and the wood vinegar spraying tower;

and cooling the pyroligneous liquor in the pyroligneous liquor bin through the second heat exchanger, and then feeding the cooled pyroligneous liquor into the pyroligneous liquor spraying tower so as to cool the condensable part in the second biogas and form pyroligneous liquor.

In one possible design, further comprising: an electrical tar precipitator;

the electrical tar precipitator is connected with the pyroligneous liquor spraying tower and is used for removing tar in the non-condensable part of the second biogas discharged from the pyroligneous liquor spraying tower.

In one possible design, further comprising: a gas turbine power generation device;

the gas turbine power generation device is respectively connected with the electric tar precipitator and the waste heat boiler, the non-condensable part in the second biogas after tar removal through the electric tar precipitator forms combustible gas, the combustible gas enters the gas turbine power generation device to be combusted and generated, and tail gas generated by the gas turbine power generation device enters the waste heat boiler.

In a second aspect, an embodiment of the present invention provides an operating method based on the biomass pyrolysis system described above, including:

drying the biomass in the biomass drying pipe by using the flue gas discharged by the waste heat boiler;

separating the biomass and the flue gas conveyed by the biomass drying pipe by using the first cyclone separator, discharging the separated flue gas through a dust remover, and conveying the separated biomass to the biomass bin;

heating the carrier in the carrier heating pipe by using hot flue gas generated by the oil-gas hot blast stove;

pyrolyzing the biomass conveyed to the pyrolysis reactor from the biomass bin by using the heated carrier;

separating a carrier and biochar generated by pyrolysis of the pyrolysis reactor by using the solid-solid separator, wherein the separated carrier enters the carrier heating pipe;

separating biochar and first biogas by using the second cyclone separator, and converting the first biogas conveyed by the second cyclone separator into bio-oil and second biogas by using the bio-oil spray tower;

introducing at least part of the bio-oil and at least part of the second biogas generated by the bio-oil spray tower into the oil-gas hot blast stove for combustion;

and absorbing the heat of the hot flue gas conveyed by the carrier heating pipe by using the waste heat boiler to generate steam, and conveying the cooled hot flue gas to the air inlet end of the biomass drying pipe by using the waste heat boiler.

In one possible design, further comprising:

introducing one path of hot flue gas conveyed by the carrier heating pipe into a fluidized bed, and introducing the other path of hot flue gas into a pipeline connected between the fluidized bed and the waste heat boiler;

and introducing the biochar separated by the solid-solid separator, the biochar stored in the biochar bin and at least part of second biogas discharged from the bio-oil spray tower into the fluidized bed for combustion.

According to the scheme, the biomass pyrolysis system and the working method thereof heat the carrier in the carrier heating pipe by utilizing the hot flue gas generated by the oil-gas hot blast stove, the heated hot flue gas is conveyed to the waste heat boiler and absorbed by the waste heat boiler, and the cooled hot flue gas is conveyed to the biomass drying pipe by the waste heat boiler so as to dry the biomass in the biomass drying pipe, so that the biomass is prevented from being carbonized by high-temperature gas, and the heat utilization rate of the pyrolysis system is also improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic diagram of a biomass pyrolysis system provided by one embodiment of the present invention;

FIG. 2 is a schematic diagram of a biomass pyrolysis system provided by another embodiment of the invention;

FIG. 3 is a schematic diagram of a biomass pyrolysis system provided by yet another embodiment of the invention;

fig. 4 is a flow chart of a method of operating a biomass pyrolysis system provided by an embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer and more complete, the technical solutions in the embodiments of the present invention will be described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention, and based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative efforts belong to the scope of the present invention.

As shown in fig. 1, an embodiment of the present invention provides a biomass pyrolysis system, including: biomass drying pipe 101, carrier heating pipe 102, pyrolysis reactor 103, first cyclone 104, second cyclone 105, exhaust-heat boiler 106, bio-oil spray tower 107 and oil gas hot-blast furnace 108, wherein:

the air outlet end of the biomass drying tube 101 is connected with the first cyclone separator 104, the air inlet end of the biomass drying tube 101 is connected with the air outlet end of flue gas in the waste heat boiler 106, biomass is contained in the biomass drying tube 101, the flue gas discharged by the waste heat boiler 106 is used for drying the biomass in the biomass drying tube 101, and the biomass can comprise straw, rice hulls, peanut shells, corncobs, oil tea shells, cottonseed shells and the like.

First cyclone 104 and pyrolysis reactor 103 pass through biomass storehouse 109 and connect, first cyclone 104 is used for separating the living beings and the flue gas that biomass drying tube 101 carried, the flue gas after the separation is discharged through dust remover 110, the living beings after the separation are carried to living beings storehouse 109, the living beings in living beings storehouse 109 are carried to pyrolysis reactor 103 and are carried out the pyrolysis, living beings produce biological charcoal and first biogas after the pyrolysis of pyrolysis reactor 103, wherein first biogas is used for changing into bio-oil and second biogas, the second biogas is used for changing into pyroligneous liquid and combustible gas.

The upper end of the carrier heating pipe 102 is connected with the pyrolysis reactor 103 through a carrier buffer bin 111, a carrier is contained in the carrier heating pipe 102, the carrier is heated in the carrier heating pipe 102 and then is conveyed to the carrier buffer bin 111, the carrier in the carrier buffer bin 111 is conveyed to the pyrolysis reactor 103, and the carrier can be ceramic balls.

The lower end of the carrier heating pipe 102 is connected with the pyrolysis reactor 103 through a solid-solid separator 112, the solid-solid separator 112 is used for separating the carrier and the biochar generated by pyrolysis of the pyrolysis reactor 103, and the separated carrier enters the carrier heating pipe 102, so that the carrier is continuously recycled.

The inlet end of the second cyclone separator 105 is connected with the upper end of the pyrolysis reactor 103, the first outlet end of the second cyclone separator 105 is connected with a charcoal bin 113, the second outlet end of the second cyclone separator 105 is connected with a bio-oil spray tower 107, the bio-oil spray tower 107 is used for converting the first bio-gas conveyed by the second cyclone separator 105 into bio-oil and a second bio-gas, wherein a part of condensable parts in the first bio-gas is condensed to form bio-oil, and the other part of condensable parts and non-condensable parts (such as methane, hydrogen and the like, namely, combustible gas) form the second bio-gas.

The oil gas hot blast stove 108 is connected with the lower end of the carrier heating pipe 102, at least part of the bio-oil and at least part of the second biogas generated by the bio-oil spray tower 107 are introduced into the oil gas hot blast stove 108 to be combusted, the oil gas hot blast stove 108 is used for heating the carrier in the carrier heating pipe 102 through the generated hot flue gas, and at least part of the bio-oil and at least part of the second biogas generated by the bio-oil spray tower 107 can be utilized by using the oil gas hot blast stove 108, namely no additional fuel is needed.

The inlet end of the flue gas in the exhaust-heat boiler 106 is connected with the upper end of the carrier heating pipe 102, the exhaust-heat boiler 106 is used for absorbing the heat of the hot flue gas conveyed by the carrier heating pipe 102 to generate steam, and meanwhile, the cooled hot flue gas is conveyed to the inlet end of the biomass drying pipe 101 by the exhaust-heat boiler 106.

In the embodiment of the present invention, the biomass pyrolysis system heats the carrier in the carrier heating pipe 102 by using the hot flue gas generated by the oil-gas hot-blast stove 108, the heated hot flue gas (about 500 ℃) is transmitted to the exhaust-heat boiler 106 and absorbed by the exhaust-heat boiler 106, and the cooled hot flue gas (about 240 ℃) is transmitted to the biomass drying pipe 101 by the exhaust-heat boiler 106 to dry the biomass in the biomass drying pipe 101, so that not only the biomass is prevented from being carbonized by the high-temperature gas, but also the heat utilization rate of the pyrolysis system is improved. Furthermore, by using waste heat boiler 106 to absorb heat from the hot flue gas output by carrier heating pipe 102, waste heat boiler 106 can also be caused to produce steam, which can be used for heating.

As shown in fig. 2, in an embodiment of the present invention, the biomass pyrolysis system further includes: a fluidized bed 114; the fluidized bed 114 is connected with the waste heat boiler 106, one path of hot flue gas conveyed by the carrier heating pipe 102 is introduced into the fluidized bed 114, the other path of hot flue gas is introduced into a pipeline 115 connected between the fluidized bed 114 and the waste heat boiler 106, and the pipeline 115 connected between the fluidized bed 114 and the waste heat boiler 106 is provided with an SNCR ammonia spraying position; the fluidized bed 114 is also connected with the solid-solid separator 112, the biochar bin 113 and the bio-oil spray tower 107 respectively, and at least part of the second biogas discharged by the biochar separated by the solid-solid separator 112, the biochar stored in the biochar bin 113 and the bio-oil spray tower 107 enters the fluidized bed 114 for combustion.

In the embodiment of the invention, currently, the biochar has no good utilization direction, and the scheme can realize reasonable utilization of high-temperature biochar (containing biochar latent heat) generated by a biomass pyrolysis system, namely, the biochar is combusted by adopting the fluidized bed 114 to generate high-temperature flue gas, and the heat of the high-temperature flue gas can be absorbed by the waste heat boiler 106, so that more steam can be generated. In order to ensure that the fluidizing effect (or the uniform distribution effect) of the fluidized bed 114 is better, one path of the hot flue gas conveyed by the carrier heating pipe 102 is introduced into the fluidized bed 114, and the oxygen content of the hot flue gas is more than 10%, so that the combustion supporting effect during the combustion of the biochar can be realized. Further, at least part of the second biogas discharged from the bio-oil spray tower 107 is also introduced into the fluidized bed 114 for combustion, so that the function of adjusting the combustion load of the fluidized bed 114 can be achieved, that is, the flow rate of the second biogas introduced into the fluidized bed 114 can be adaptively controlled according to the actual demand load.

In addition, the temperature of the flue gas generated by the combustion of the fluidized bed 114 can reach over 1000 ℃, the other path of the hot flue gas conveyed by the carrier heating pipe 102 is introduced into a pipeline 115 connected between the fluidized bed 114 and the waste heat boiler 106, so that the temperature of the flue gas in the pipeline 115 can be reduced, the position of the flue gas with the temperature of 850-900 ℃ is determined in the pipeline 115 and is used as an SNCR ammonia spraying position, and whether ammonia spraying needs to be carried out on the SNCR ammonia spraying position or not can be adaptively selected according to local environmental protection requirements. Compared with SCR denitration, because the SNCR ammonia spraying position does not contain a catalyst, the SNCR ammonia spraying position does not have the problems of catalyst poisoning and blockage, and the cost is low.

As shown in fig. 3, in an embodiment of the present invention, a bio-oil bin 116 for storing bio-oil is connected to the bio-oil spray tower 107, and a first heat exchanger 117 is connected between the bio-oil bin 116 and the bio-oil spray tower 107; the bio-oil in the bio-oil bin 116 enters the bio-oil spray tower 107 after being cooled by the first heat exchanger 117, so as to cool a part of condensable parts in the first biogas and form the bio-oil. That is, after a part of the bio-oil in the bio-oil bin 116 is cooled, a part of the condensable part of the first biogas can be cooled more efficiently. Of course, the bio-oil spray tower 107 may also take other forms of condensation.

With continuing reference to fig. 3, in one embodiment of the present invention, the biomass pyrolysis system further comprises: a pyroligneous liquor spray tower 118; the pyroligneous liquor spraying tower 118 is connected with a pyroligneous liquor bin 119 for storing pyroligneous liquor, and a second heat exchanger 120 is connected between the pyroligneous liquor bin 119 and the pyroligneous liquor spraying tower 118; the pyroligneous liquor in the pyroligneous liquor storage 119 is cooled by the second heat exchanger 120 and then enters the pyroligneous liquor spraying tower 118, so that the condensable part in the second biogas is cooled and pyroligneous liquor is formed. That is, after a part of the pyroligneous liquor in the pyroligneous liquor storage 119 is cooled, the condensable part of the second biogas (i.e., another condensable part of the first biogas) can be cooled more efficiently. Of course, the pyroligneous liquor spray tower 118 may also take other forms of condensation.

Referring to fig. 3, in an embodiment of the invention, the method further includes: an electrical tar precipitator 121; an electrical tar precipitator 121 is connected to the pyroligneous liquor spray tower 118, and the electrical tar precipitator 121 is used for removing tar in the non-condensable portion of the second biogas discharged from the pyroligneous liquor spray tower 118. The electrical tar precipitator 121 has the advantages of high tar precipitation efficiency, small resistance loss, large gas handling capacity and the like, and in addition, the electrical tar precipitator 121 can not only ensure the requirements of the subsequent processes on the gas quality and improve the product recovery rate, but also obviously improve the operating environment.

Referring to fig. 3, in an embodiment of the invention, the method further includes: a combustion engine power generation device 122; the gas turbine power generation device 122 is respectively connected with the electrical tar precipitator 121 and the waste heat boiler 106, the non-condensable part of the second biogas after tar removal by the electrical tar precipitator 121 forms combustible gas, the combustible gas enters the gas turbine power generation device 122 for combustion power generation, and tail gas generated by the gas turbine power generation device 122 enters the waste heat boiler 106. In the embodiment of the invention, the combustible gas purified by the pyroligneous liquor spray tower 118 enters the electrical tar precipitator 121 for secondary purification to produce biogas suitable for requirements of a combustion engine power generation device 122 (such as an internal combustion engine and a micro-combustion engine) so as to generate electric power; also, the exhaust gas generated by the combustion engine power generation device 122 enters the waste heat boiler 106 to be utilized by the waste heat boiler 106 and generate steam.

In summary, the biomass pyrolysis system provided by the embodiment of the invention can utilize various cheap biomass resources (such as straw, rice hull, peanut shell, corn cob, oil tea hull and cottonseed hull) to produce products such as bio-oil, bio-gas, bio-charcoal, steam, electric power and pyroligneous liquor in a combined manner according to local project requirements, the product combination is flexible, and the proportion of each product can be adjusted according to actual conditions. In addition, this biomass pyrolysis system has still solved the environmental protection emission problem of living beings utilization technique through setting up SNCR and spouting ammonia level.

As shown in fig. 4, an embodiment of the present invention further provides an operating method of a biomass pyrolysis system based on the foregoing, where the operating method includes:

s1, drying the biomass in the biomass drying pipe 101 by using the flue gas discharged by the waste heat boiler 106;

s2, separating the biomass and the flue gas conveyed by the biomass drying pipe 101 by using the first cyclone separator 104, discharging the separated flue gas through the dust remover 110, and conveying the separated biomass to the biomass bin 109;

s3, heating the carrier in the carrier heating pipe 102 by using hot flue gas generated by the oil-gas hot blast stove 108;

s4, pyrolyzing the biomass conveyed to the pyrolysis reactor 103 from the biomass bin 109 by using the heated carrier;

s5, separating the carrier and the biochar generated by pyrolysis in the pyrolysis reactor 103 by using a solid-solid separator 112, and enabling the separated carrier to enter a carrier heating pipe 102;

s6, separating the biochar and the first biogas by using the second cyclone separator 105, and converting the first biogas conveyed by the second cyclone separator 105 into bio-oil and second biogas by using the bio-oil spray tower 107;

s7, introducing at least part of the bio-oil and at least part of the second biogas generated by the bio-oil spray tower 107 into the oil-gas hot blast stove 108 for combustion;

s8, the exhaust-heat boiler 106 is used to absorb heat of the hot flue gas delivered by the carrier heating pipe 102 to generate steam, and the cooled hot flue gas is delivered to the air inlet end of the biomass drying pipe 101 by the exhaust-heat boiler 106.

In one embodiment of the present invention, further comprising:

one path of hot flue gas conveyed by the carrier heating pipe 102 is introduced into the fluidized bed 114, and the other path is introduced into a pipeline 115 connected between the fluidized bed 114 and the waste heat boiler 106;

and introducing the biochar separated by the solid-solid separator 112, the biochar stored in the biochar bin 113 and at least part of the second biogas discharged from the bio-oil spray tower 107 into a fluidized bed 114 for combustion.

The content of the process executed between the steps of the working method is based on the same concept as the embodiment of the biomass pyrolysis system of the present invention, and specific content can be referred to the description in the embodiment of the biomass pyrolysis system of the present invention, and is not repeated here.

In summary, the biomass pyrolysis system and the working method thereof provided by each of the embodiments of the present invention at least have the following beneficial effects:

1. in the embodiment of the present invention, the biomass pyrolysis system heats the carrier in the carrier heating pipe 102 by using the hot flue gas generated by the oil-gas hot-blast stove 108, the heated hot flue gas (about 500 ℃) is transmitted to the exhaust-heat boiler 106 and absorbed by the exhaust-heat boiler 106, and the cooled hot flue gas (about 240 ℃) is transmitted to the biomass drying pipe 101 by the exhaust-heat boiler 106 to dry the biomass in the biomass drying pipe 101, so that not only the biomass is prevented from being carbonized by the high-temperature gas, but also the heat utilization rate of the pyrolysis system is improved. Furthermore, by using waste heat boiler 106 to absorb heat from the hot flue gas output by carrier heating pipe 102, waste heat boiler 106 can also be caused to produce steam, which can be used for heating.

2. In the embodiment of the invention, currently, the biochar has no good utilization direction, and the scheme can realize reasonable utilization of high-temperature biochar (containing biochar latent heat) generated by a biomass pyrolysis system, namely, the biochar is combusted by adopting the fluidized bed 114 to generate high-temperature flue gas, and the heat of the high-temperature flue gas can be absorbed by the waste heat boiler 106, so that more steam can be generated. In order to ensure that the fluidizing effect (or the uniform distribution effect) of the fluidized bed 114 is better, one path of the hot flue gas conveyed by the carrier heating pipe 102 is introduced into the fluidized bed 114, and the oxygen content of the hot flue gas is more than 10%, so that the combustion supporting effect during the combustion of the biochar can be realized. Further, at least part of the second biogas discharged from the bio-oil spray tower 107 is also introduced into the fluidized bed 114 for combustion, so that the function of adjusting the combustion load of the fluidized bed 114 can be achieved, that is, the flow rate of the second biogas introduced into the fluidized bed 114 can be adaptively controlled according to the actual demand load.

3. In the embodiment of the invention, the temperature of the flue gas generated by the combustion of the fluidized bed 114 can reach more than 1000 ℃, the other path of the hot flue gas conveyed by the carrier heating pipe 102 is introduced into the pipeline 115 connected between the fluidized bed 114 and the waste heat boiler 106, so that the temperature of the flue gas in the pipeline 115 can be reduced, the position with the flue gas temperature of 850-900 ℃ is determined in the pipeline 115 and is used as an SNCR ammonia spraying position, and whether ammonia spraying is required to be carried out on the SNCR ammonia spraying position or not can be adaptively selected according to local environmental protection requirements. Compared with SCR denitration, because the SNCR ammonia spraying position does not contain a catalyst, the SNCR ammonia spraying position does not have the problems of catalyst poisoning and blockage, and the cost is low.

4. The combustible gas purified by the pyroligneous liquor spray tower 118 enters an electric tar precipitator 121 for secondary purification to produce biogas suitable for requirements of a combustion engine power generation device 122 (such as an internal combustion engine and a micro-combustion engine) so as to generate electric power; also, the exhaust gas generated by the combustion engine power generation device 122 enters the waste heat boiler 106 to be utilized by the waste heat boiler 106 and generate steam.

It should be noted that not all steps and modules in the above flows and system structure diagrams are necessary, and some steps or modules may be omitted according to actual needs. The execution order of the steps is not fixed and can be adjusted as required. The system structures described in the above embodiments may be physical structures or logical structures, that is, some modules may be implemented by the same physical entity, or some modules may be implemented by several physical entities, or some components may be implemented by several independent devices.

In the description of the embodiments of the present invention, unless explicitly specified or limited otherwise, the terms "first", "second", and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; the term "a plurality" means two or more unless specified or stated otherwise; the terms "connected," "fixed," and the like are to be construed broadly and may, for example, be fixedly connected, detachably connected, integrally connected, or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the description of the present invention, it should be understood that the terms "upper" and "lower" as used in the description of the embodiments of the present invention are used in the angle shown in the drawings, and should not be construed as limiting the embodiments of the present invention. In addition, in this context, it will also be understood that when an element is referred to as being "on" or "under" another element, it can be directly on "or" under "the other element or be indirectly on" or "under" the other element via an intermediate element.

While the invention has been shown and described in detail in the drawings and in the preferred embodiments, it is not intended to limit the invention to the embodiments disclosed, and it will be apparent to those skilled in the art that various combinations of the code auditing means in the various embodiments described above may be used to obtain further embodiments of the invention, which are also within the scope of the invention.