System and method for producing byproduct gas and fuel oil from rice husk pyrolysis to produce white carbon black

Abstract

The present invention discloses a system and method for producing byproduct gas and fuel oil from rice husk pyrolysis. Rice husk is sent to a pyrolysis reactor and fully mixed with a high-temperature heat carrier for pyrolysis reaction to produce high-temperature oil and gas. The high-temperature oil and gas are sent to an oil-water spray tower for cooling to obtain bio-oil and biomass gas products. The heat carrier discharged from the pyrolysis reactor and the rice husk pyrolysis char are sent to a low-temperature combustion reactor for low-temperature combustion. The generated heat carrier and rice husk white carbon black enter a carrier separator, and the heat carrier and rice husk white carbon black are separated to obtain a rice husk white carbon black product. The separated heat carrier is sent to an air flow conveying pipe, and the flue gas generated by the low-temperature burner is sent to the air flow conveying pipe through a high-temperature fan. The high-temperature flue gas conveys the heat carrier to a cyclone separator, and the separated heat carrier enters a carrier buffer hopper and is sent to a pyrolysis reactor. The flue gas separated from the cyclone enters a nitrogen heat exchange tank to heat the nitrogen. The overall system of the present invention is simple in equipment, easy to operate, high in thermal efficiency, and simple in process flow.

Description

Technical Field

[0001] The invention relates to a system and method for producing white carbon black byproduct gas and fuel oil by gas-solid dual-circulation pyrolysis and temperature-controlled combustion of rice husk, and belongs to the field of production and equipment of rice husk white carbon black and byproduct gas and fuel oil. Background Art

[0002] Rice husk has a high silicon content, which can account for more than 90% of its ash, and almost all of the SiO2 contained in rice husk exists in the form of amorphous hydrated SiO2, making it a very high-quality raw material for preparing white carbon black.

[0003] In the process of preparing white carbon black using rice husk as raw material by pyrolysis reaction and low-temperature combustion, a large amount of high-temperature fuel oil will be generated in the pyrolysis reaction, and a large amount of flue gas or fuel gas will be generated during the low-temperature combustion. The existing device for preparing white carbon black using rice husk as raw material cannot comprehensively utilize the high-temperature fuel oil and flue gas or fuel gas generated in the preparation process, and cannot simultaneously achieve the co-production of white carbon black, fuel oil and fuel gas, which urgently needs to be improved. Summary of the invention

[0004] The purpose of the present invention is to provide a system and method for producing by-product gas and fuel oil from white carbon black by pyrolysis of rice husks, so as to solve the above-mentioned problems existing in the prior art.

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

[0006] One aspect of the present invention is to provide a system for producing by-product gas and fuel oil from rice husk pyrolysis of white carbon black, comprising: an air flow conveying pipe, a cyclone separator, a high-temperature carrier buffer hopper, a rice husk raw material bin, a pyrolysis reactor, a low-temperature combustion reactor, a carrier separator, a high-temperature blower, an oil-water spray tower, a circulation pump, a cooling tower, a gas induced draft fan and a nitrogen heat exchange tank; the material outlet of the air flow conveying pipe is connected to the inlet of the cyclone separator; the gas outlet of the cyclone separator is connected to the flue gas inlet of the nitrogen heat exchange tank; the solid matter outlet of the cyclone separator is connected to the inlet of the high-temperature carrier buffer hopper; the outlet of the high-temperature carrier buffer hopper and the outlet of the rice husk raw material bin are both connected to the raw material inlet of the pyrolysis reactor; the pyrolysis The solid matter outlet of the reactor is connected to the solid material inlet of the low-temperature combustion reactor; the solid material outlet of the low-temperature combustion reactor is connected to the inlet of the carrier separator; the smoke outlet of the low-temperature combustion reactor is connected to the gas inlet of the airflow conveying pipe through a high-temperature blower; the carrier outlet of the carrier separator is connected to the solid inlet of the airflow conveying pipe; the oil and gas outlet of the pyrolysis reactor is connected to the gas inlet of the oil-water spray tower; the liquid outlet of the oil-water spray tower is connected to the inlet of the circulation pump; the outlet of the circulation pump is connected to the inlet of the cooling tower; the outlet of the cooling tower is connected to the spray liquid inlet of the oil-water spray tower; the gas outlet of the oil-water spray tower is connected to the gas inlet of the gas induced draft fan.

[0007] As a preferred specific embodiment of the present invention, the pyrolysis reactor includes a shell and a double-helix agitator, the double-helix agitator is installed at the lower part of the shell, a solid inlet and a solid outlet are respectively provided at the front end top and the rear end bottom of the shell; an oil and gas outlet is provided at the rear end top of the shell; and an insulation layer is provided on the outer side of the shell.

[0008] As a preferred specific embodiment of the present invention, a material-shifting piece is provided on one side of the outer edge of the spiral blades of each circle of the double-helix agitator facing the rear end.

[0009] As a preferred specific embodiment of the present invention, a high-temperature oil and gas filter is installed at the oil and gas outlet of the pyrolysis reactor, and the outlet of the high-temperature oil and gas filter is connected to the gas inlet of the oil-water spray tower; the backflush interface of the high-temperature oil and gas filter is connected to the nitrogen outlet of the nitrogen heat exchange tank.

[0010] As a preferred specific implementation scheme of the present invention, the high-temperature oil and gas filter adopts a ceramic filter, and an electric heater is arranged on the outside of the ceramic filter.

[0011] As a preferred specific embodiment of the present invention, the low-temperature combustion reactor includes a shell, a circular height limiting ring, a material shifting piece, a chain conveyor and a ceramic air inlet pipe, wherein a solid material inlet and a solid material outlet are respectively provided at the front end top and the rear end bottom of the shell; a flue gas outlet is provided at the rear end top of the shell; a chain conveyor is provided in the middle of the shell; a circular height limiting ring is provided at a position behind the solid material inlet of the shell, and a material shifting piece is provided inside the circular height limiting ring; a ceramic air inlet pipe and a temperature measuring point for blowing air are provided on the shell.

[0012] Another aspect of the present invention is to provide a method for producing white carbon black by-product gas and fuel oil system by pyrolysis of rice husk, comprising:

[0013] 1) The rice husks and high-temperature heat carrier in the rice husk raw material bin are sent to the pyrolysis reactor through a screw conveyor, the rice husks and the high-temperature heat carrier are fully mixed, and the rice husks are heated by the high-temperature heat carrier to undergo pyrolysis reaction to produce high-temperature oil and gas, and the reaction temperature is 450° C. to 550° C.;

[0014] 2) The high-temperature oil and gas produced by the pyrolysis reactor are filtered through a high-temperature oil and gas filter and sent to an oil-water spray tower for cooling to 50°C to 70°C to obtain bio-oil and biomass gas products;

[0015] 3) The heat carrier and rice husk pyrolysis char discharged from the pyrolysis reactor are sent to a low-temperature combustion reactor for low-temperature combustion at a combustion temperature of 550°C to 600°C;

[0016] 4) The heat carrier and rice husk white carbon black generated after low-temperature combustion enter the carrier separator, and the heat carrier and rice husk white carbon black are separated to obtain the rice husk white carbon black product;

[0017] 5) The separated heat carrier is sent to the air flow pipe, and the flue gas generated by the low-temperature combustion reactor is sent to the air flow pipe through the high-temperature blower. The high-temperature flue gas transports the heat carrier in the air flow pipe to the cyclone separator for separation. The separated heat carrier enters the carrier buffer hopper and is sent to the pyrolysis reactor through the screw conveyor as a heat source for pyrolysis reaction;

[0018] 6) The flue gas separated from the cyclone separator enters the nitrogen heat exchange tank and is heated to 400°C. The nitrogen after heat exchange is regularly back-blown through the high-temperature oil and gas filter of the pyrolysis reactor.

[0019] The present invention adopts a gas-solid dual-cycle pyrolysis heating decarbonization and low-temperature combustion method to prepare nano-white carbon black. The obtained nano-white carbon black meets the key indicators of gas-phase white carbon black. The process flow is simple, which can achieve high-value utilization of resources and significantly improve the economic benefits of the project. The overall system equipment is simple, easy to operate, and has high thermal efficiency. Rice husks are used to achieve the co-production of white carbon black, fuel oil, and gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the by-product gas and fuel oil system of producing white carbon black by pyrolysis of rice husks according to the present invention;

[0021] Figure 2 It is a schematic structural diagram of a pyrolysis reactor of the present invention;

[0022] Figure 3 It is a partial enlarged view of the double-screw agitator of the pyrolysis reactor of the present invention;

[0023] Figure 4 It is a schematic structural diagram of the low-temperature combustion reactor of the present invention.

[0024] Explanation of reference numerals: 1. air flow conveying pipe; 2. cyclone separator; 3. high-temperature carrier buffer hopper; 4. rice husk raw material warehouse; 5. pyrolysis reactor; 6. low-temperature combustion reactor; 7. carrier separator; 8. high-temperature blower; 9. oil-water spray tower; 10. circulation pump; 11. cooling tower; 12. gas induced draft fan; 13. nitrogen heat exchange tank; 101. air input interface; 102. nitrogen input interface; 103. flue gas outlet; 104. biomass gas product outlet; 105. bio-oil product outlet; 106. white carbon black outlet;

[0025] 51. Raw material inlet; 52. High-temperature oil and gas filter; 53. Double-screw agitator; 54. Solid matter outlet; 55. Casing; 56. Electric heater;

[0026] 61. Solid material inlet; 62. Circular height limit ring; 63. Material shifting plate; 64. Chain conveyor; 65. Smoke outlet; 66. Shell; 67. Solid material outlet; 68. Ceramic air inlet pipe; 69. Temperature measuring point. DETAILED DESCRIPTION

[0027] See also Figure 1-Figure 4 The present invention provides a rice husk pyrolysis production of white carbon black by-product gas and fuel oil system, comprising: an air flow conveying pipe 1, a cyclone separator 2, a high-temperature carrier buffer hopper 3, a rice husk raw material bin 4, a pyrolysis reactor 5, a low-temperature combustion reactor 6, a carrier separator 7, a high-temperature blower 8, an oil-water spray tower 9, a circulating pump 10, a cooling tower 11, a gas induced draft fan 12 and a nitrogen heat exchange tank 13, wherein the material outlet of the air flow conveying pipe 1 is connected to the inlet of the cyclone separator 2; the gas outlet of the cyclone separator 2 is connected to the flue gas inlet of the nitrogen heat exchange tank 13; the solid matter outlet of the cyclone separator 2 is connected to the inlet of the high-temperature carrier buffer hopper 3; the outlet of the high-temperature carrier buffer hopper 3 and the outlet of the rice husk raw material bin 4 are both connected to the raw material inlet 51 of the pyrolysis reactor 5; the pyrolysis reactor The solid matter outlet of the reactor 5 is connected to the solid material inlet of the low-temperature combustion reactor 6; the solid material outlet of the low-temperature combustion reactor 6 is connected to the inlet of the carrier separator 7; the smoke outlet of the low-temperature combustion reactor 6 is connected to the gas inlet of the airflow conveying pipe 1 through the high-temperature blower 8; the carrier outlet of the carrier separator 7 (screening device) is connected to the solid inlet of the airflow conveying pipe 1; the oil and gas outlet of the pyrolysis reactor 5 is connected to the gas inlet of the oil-water spray tower 9; the liquid outlet of the oil-water spray tower 9 is connected to the inlet of the circulation pump 10; the outlet of the circulation pump 10 is connected to the inlet of the cooling tower 11; the outlet of the cooling tower 11 is connected to the spray liquid inlet of the oil-water spray tower 9; the gas outlet of the oil-water spray tower 9 is connected to the gas inlet of the gas induced draft fan 12.

[0028] See also Figure 2 and Figure 3 The pyrolysis reactor 5 includes a shell 55 and a double-screw agitator 53. The double-screw agitator 53 is installed at the lower part of the shell 55. A solid inlet 51 and a solid outlet 54 are respectively provided at the front end top and the rear end bottom of the shell 55; an oil and gas outlet is provided at the rear end top of the shell 55; and an insulation layer is provided on the outer side of the shell 55.

[0029] A material-shifting piece 531 is provided on the outer edge of each spiral blade of the double-screw agitator 53 , facing the rear end.

[0030] A high-temperature oil and gas filter 52 is installed at the oil and gas outlet of the pyrolysis reactor 5, and the outlet of the high-temperature oil and gas filter 52 is connected to the gas inlet of the oil-water spray tower 9; the backflush interface of the high-temperature oil and gas filter 52 is connected to the nitrogen outlet of the nitrogen heat exchange tank 13.

[0031] The high-temperature oil and gas filter 52 is a ceramic filter, and an electric heater 56 (such as a heating wire) is provided on the outside of the ceramic filter.

[0032] The pyrolysis reactor 5 is characterized in that the heat carrier and the rice husk can be fully mixed, and the heat carrier transfers heat to the rice husk to cause a pyrolysis reaction during the mixing process, and the heat transfer efficiency is high. The high-temperature oil and gas filter 52 configured therein is used for filtering high-temperature oil and gas, and the oil and gas filter is heated by an electric heater 56 outside the filter to ensure that the oil and gas do not condense and cause the filter to be blocked.

[0033] See also Figure 4 The low-temperature combustion reactor 6 includes a shell 66, a circular height-limiting ring 62, a material-shifting piece 63, a chain conveyor 64 and a ceramic air inlet pipe 68. A solid material inlet 61 and a solid material outlet 67 are respectively provided at the top of the front end and the bottom of the rear end of the shell 66; a smoke outlet 65 is provided at the top of the rear end of the shell 66; a chain conveyor 64 is provided in the middle of the shell 66; a circular height-limiting ring 62 is provided behind the solid material inlet 61 of the shell 66, and a material-shifting piece 63 is provided in the circular height-limiting ring 62; a ceramic air inlet pipe 68 for blowing air and a temperature measuring point 69 for placing a thermometer are provided on the shell 66.

[0034] When the low-temperature combustion reactor 6 is working, the heat carrier and rice husk charcoal enter the circular height-limiting circle 62 from the solid material inlet 61. The material-shifting sheet 63 in the circular height-limiting circle makes the material evenly distributed. The circular height-limiting circle 62 limits the material layer height on the chain conveyor 64 to achieve the effect of a 10 mm thin layer. Air is evenly blown in from the air input interface 101 through the ceramic air inlet pipe 68 to cause the rice husk charcoal to undergo a combustion reaction. Due to the thin thickness of the material, the combustion heat will be quickly dissipated without heat accumulation, and the heat carrier is mixed with the rice husk charcoal, and the combustion heat of the rice husk charcoal will be absorbed by the heat carrier. This low-temperature combustion reactor 6 mainly adopts two means: heat absorption by the heat carrier and rapid heat dissipation of the thin layer to achieve the purpose of low-temperature combustion of the rice husk charcoal. It burns slowly below 600°C without destroying the amorphous SiO2 form of the rice husk itself, thereby achieving the purpose of producing rice husk white carbon black. According to the temperature value detected by the thermometer at the temperature measuring point 69, the amount of air entering is controlled to achieve the purpose of controlling combustion.

[0035] The present invention provides a method for producing white carbon black by-product gas and fuel oil by pyrolysis of rice husk (i.e., the working process of the above system), comprising the following steps:

[0036] 1) The rice husk and the high-temperature heat carrier in the rice husk raw material bin 4 are sent to the pyrolysis reactor 5 through a screw conveyor, the rice husk and the high-temperature heat carrier are fully mixed, and the rice husk is heated by the high-temperature heat carrier to undergo a pyrolysis reaction to produce high-temperature oil and gas, and the reaction temperature is 450° C. to 550° C.; in the initial operation, a heating device (not shown) is required to heat the heat carrier to 450° C. to 550° C., and after working for one cycle (i.e., the following step 5), the heat generated by itself can be used to maintain operation.

[0037] 2) The high-temperature oil and gas generated by the pyrolysis reactor 5 is filtered by the high-temperature oil and gas filter 52 and then sent to the oil-water spray tower 9 for cooling to 50° C. to 70° C. to obtain bio-oil and biomass gas products;

[0038] 3) The heat carrier and rice husk pyrolysis char discharged from the pyrolysis reactor 5 are sent to the low-temperature combustion reactor 6 for low-temperature combustion at a combustion temperature of 550°C to 600°C;

[0039] 4) The heat carrier and rice husk white carbon black generated after low-temperature combustion enter the carrier separator 7, and the heat carrier and rice husk white carbon black are separated to obtain a rice husk white carbon black product;

[0040] 5) The separated heat carrier is sent to the air flow pipe 1, and the flue gas generated by the low-temperature combustion reactor 6 is sent to the air flow pipe 1 through the high-temperature blower 8. The high-temperature flue gas transports the heat carrier in the air flow pipe 1 to the cyclone separator 2 for separation. The separated heat carrier enters the carrier buffer hopper 3 and is sent to the pyrolysis reactor 5 through the screw conveyor as a heat source for pyrolysis reaction;

[0041] 6) The flue gas separated from the cyclone separator 2 enters the nitrogen heat exchange tank 13 and is heated to 400° C. The nitrogen after heat exchange is periodically back-blown through the high-temperature oil and gas filter 52 of the pyrolysis reactor 5 .

Claims

1. A system for producing byproduct gas and fuel oil from white carbon black by pyrolysis of rice husks, characterized in that: include: An air flow conveying pipe (1), a cyclone separator (2), a high-temperature carrier buffer hopper (3), a rice husk raw material bin (4), a pyrolysis reactor (5), a low-temperature combustion reactor (6), a carrier separator (7), a high-temperature blower (8), an oil-water spray tower (9), a circulation pump (10), a cooling tower (11), a gas induced draft fan (12) and a nitrogen heat exchange tank (13); the material outlet of the air flow conveying pipe (1) is connected to the inlet of the cyclone separator (2); the gas outlet of the cyclone separator (2) is connected to the flue gas inlet of the nitrogen heat exchange tank (13); the solid matter outlet of the cyclone separator (2) is connected to the inlet of the high-temperature carrier buffer hopper (3); the outlet of the high-temperature carrier buffer hopper (3) and the outlet of the rice husk raw material bin (4) are both connected to the raw material inlet (51) of the pyrolysis reactor (5); the solid matter outlet of the pyrolysis reactor (5) is connected to the raw material inlet (52) of the pyrolysis reactor (5); The inlet of the low-temperature combustion reactor (6) is connected to the solid material inlet of the low-temperature combustion reactor (6); the solid material outlet of the low-temperature combustion reactor (6) is connected to the inlet of the carrier separator (7); the smoke outlet of the low-temperature combustion reactor (6) is connected to the gas inlet of the air flow conveying pipe (1) through the high-temperature blower (8); the carrier outlet of the carrier separator (7) is connected to the solid inlet of the air flow conveying pipe (1); the oil and gas outlet of the pyrolysis reactor (5) is connected to the gas inlet of the oil-water spray tower (9); the liquid outlet of the oil-water spray tower (9) is connected to the inlet of the circulation pump (10); the outlet of the circulation pump (10) is connected to the inlet of the cooling tower (11); the outlet of the cooling tower (11) is connected to the spray liquid inlet of the oil-water spray tower (9); the gas outlet of the oil-water spray tower (9) is connected to the gas inlet of the gas induced draft fan (12); The low-temperature combustion reactor (6) comprises a shell (66), a circular height-limiting ring (62), a material-shifting plate (63), a chain conveyor (64) and a ceramic air inlet pipe (68). A solid material inlet (61) and a solid material outlet (67) are respectively provided at the top of the front end and the bottom of the rear end of the shell (66); a smoke outlet (65) is provided at the top of the rear end of the shell (66); a chain conveyor (64) is provided in the middle of the shell (66); a circular height-limiting ring (62) is provided at a position behind the solid material inlet (61) of the shell (66), and a material-shifting plate (63) is provided in the circular height-limiting ring (62); and a ceramic air inlet pipe (68) for blowing in air and a temperature measuring point (69) are provided on the shell (66).

2. The system for producing byproduct gas and fuel oil from rice husk pyrolysis to produce white carbon black according to claim 1, characterized in that: The pyrolysis reactor (5) comprises a shell (55) and a double-screw agitator (53). The double-screw agitator (53) is installed at the lower part of the shell (55). A raw material inlet (51) and a solid matter outlet (54) are respectively provided at the front top and rear bottom of the shell (55); an oil and gas outlet is provided at the rear top of the shell (55); and a heat-insulating layer is provided on the outer side of the shell (55).

3. The system for producing byproduct gas and fuel oil from white carbon black by pyrolysis of rice husk according to claim 2, characterized in that: A material-shifting piece is provided on the outer edge of each spiral blade of the double-screw agitator (53) on one side facing the rear end.

4. The system for producing byproduct gas and fuel oil from white carbon black by pyrolysis of rice husk according to claim 2, characterized in that: A high-temperature oil and gas filter (52) is installed at the oil and gas outlet of the pyrolysis reactor (5), and the outlet of the high-temperature oil and gas filter (52) is connected to the gas inlet of the oil-water spray tower (9); and the backflush interface of the high-temperature oil and gas filter (52) is connected to the nitrogen outlet of the nitrogen heat exchange tank (13).

5. The system for producing byproduct gas and fuel oil from white carbon black by pyrolysis of rice husk according to claim 4, characterized in that: The high-temperature oil and gas filter (52) is a ceramic filter, and an electric heater (56) is provided on the outside of the ceramic filter.

6. A method for producing white carbon black by-product gas and fuel oil system by pyrolysis of rice husk according to claim 1, characterized in that: The following steps are involved: 1) The rice husks and the high-temperature heat carrier in the rice husk raw material bin (4) are sent to the pyrolysis reactor (5) through a screw conveyor, the rice husks and the high-temperature heat carrier are fully mixed, and the rice husks are heated by the high-temperature heat carrier to undergo a pyrolysis reaction to generate high-temperature oil and gas, and the reaction temperature is 450° C. to 550° C.; 2) The high-temperature oil and gas generated by the pyrolysis reactor (5) is filtered by a high-temperature oil and gas filter (52) and then sent to an oil-water spray tower (9) for cooling to 50° C. to 70° C. to obtain bio-oil and biomass gas products; 3) The heat carrier and rice husk pyrolysis char discharged from the pyrolysis reactor (5) are sent to a low-temperature combustion reactor (6) for low-temperature combustion at a combustion temperature of 550° C. to 600° C.; 4) The heat carrier and rice husk white carbon black generated after the low-temperature combustion enter the carrier separator (7), and the heat carrier and the rice husk white carbon black are separated to obtain a rice husk white carbon black product; 5) The separated heat carrier is sent to the air flow pipe (1), the flue gas generated by the low-temperature combustion reactor (6) is sent to the air flow pipe (1) via the high-temperature blower (8), the high-temperature flue gas transports the heat carrier in the air flow pipe (1) to the cyclone separator (2) for separation, the separated heat carrier enters the carrier buffer hopper (3), and is sent to the pyrolysis reactor (5) via the screw conveyor as a heat source for pyrolysis reaction; 6) The flue gas separated from the cyclone separator (2) enters the nitrogen heat exchange tank (13) and is heated to 400°C. The nitrogen after the heat exchange is periodically back-blown through the high-temperature oil and gas filter (52) of the pyrolysis reactor (5).

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