CN114736703A

CN114736703A - Rotary downdraft straw pyrolysis carbon gas co-production equipment

Info

Publication number: CN114736703A
Application number: CN202210407658.9A
Authority: CN
Inventors: 丛宏斌; 孟海波; 于炳驰; 邢浩翰; 秦超
Original assignee: Academy of Agricultural Planning and Engineering MARA
Current assignee: Academy of Agricultural Planning and Engineering MARA
Priority date: 2022-04-19
Filing date: 2022-04-19
Publication date: 2022-07-12

Abstract

The invention discloses rotary downdraft straw pyrolysis carbon gas co-production equipment which comprises a pyrolysis cylinder, a carbon discharging device and a bracket for supporting the pyrolysis cylinder and the carbon discharging device; the pyrolysis cylinder comprises an upper section cylinder body, a middle section cylinder body and a lower section cylinder body, wherein the middle section cylinder body can rotate by taking the axis of the cylinder as the center, a material pressing device is arranged at the top of the middle section cylinder body, and a stirring rod and an air inlet rod are arranged on the inner wall of the middle section cylinder body; the carbon output device comprises a conical rotary cylinder, a spiral carbon output plate and a spiral carbon output cylinder; the conical rotary cylinder is arranged at the bottom of the lower section cylinder body, the spiral carbon conveying plate is fixedly connected in the conical rotary cylinder, a water inlet cavity is arranged at the bottom of the conical rotary cylinder, the water inlet cavity is connected with a water tank through a water conveying pipe, and the bottom of the water inlet cavity is communicated with a feed inlet of the spiral carbon outlet cylinder; the rotary downdraft straw pyrolysis carbon gas co-production equipment can solve the problems of slag bonding, bridging and arch bonding in the pyrolysis and conveying processes of materials, and greatly improves the carbon discharging tightness and stability of the system.

Description

Rotary downdraft straw pyrolysis carbon gas co-production equipment

Technical Field

The invention relates to the technical field of pyrolysis equipment, in particular to rotary downdraft straw pyrolysis carbon gas co-production equipment.

Background

At present, the working principle of the existing downdraft pyrolysis equipment is as follows: the material enters the pyrolysis reactor through the feeder, the feeding is stopped when the material reaches a certain height, and pyrolysis is started after ignition. When the pyrolysis is carried out to a certain degree, the generated biochar is discharged through a carbon discharging device; the pyrolysis gas is discharged through the exhaust port of the apparatus. Patent No. CN105505469A mentions a downdraft fixed bed gasification steam power generation cogeneration device, which comprises a gasification system and a power generation system. The gasification system comprises a feeding device, a primary air port, a secondary air port, a kick-out device, a fire grate and the like; the power generation system comprises a gas combustion chamber, a pyrolysis gas fan, a cyclone separator, a desulfurization chamber and the like. The material gets into the gasifier through feeding device and carries out pyrolysis gasification, stirs the material with the setting gauge in the pyrolysis process, but the setting gauge is fixed on the axis of rotation, and intensity is lower. Patent No. CN 110819387A provides a closed downdraft gasification furnace, which comprises a furnace body, a furnace top bin, a gas locking and discharging valve, a material spreading speed reducer, a material spreading baffle plate, fuel, a furnace grate, an ash blocking cone, an air cavity, a furnace disc, a cone lower end cover, a gas pipe, a fan, an air inlet pipe, a carbon discharging conveyor, a carbon discharging and gas locking device and a pressure relief opening. After the material is fed into the furnace, the material is flattened by the material spreading scraper, the generated combustible gas is fed into the gas cavity by the grate with gas holes on the surface, and finally the combustible gas is fed into the purification equipment by the gas pipe, so that the dust and smoke are prevented from emitting outwards during feeding. However, the carbon discharge sealing device adopted by the invention has poor sealing performance and risks of material blockage.

The technical problems existing in the prior art are as follows:

1) when biomass raw materials, particularly corn straws, are pyrolyzed, the materials have poor fluidity and contain alkali metals, and when the pyrolysis temperature reaches more than 750 ℃, the alkali metals in the straws can be separated out, so that the raw materials are bonded together to form block mass substances. These agglomerates are very hard and can not only affect the pyrolysis process, but can also cause damage to the equipment. The existing equipment is generally that a stirring rod is additionally arranged in a furnace body, stirring is ceaselessly performed in the pyrolysis process, but the stirring rod and a motor are easy to damage due to high temperature and heavy materials in the furnace.

2) Because the pyrolysis zone temperature is higher, the material particle diameter is less, the phenomenon of slagging scorification often appears, and the lump that slagging scorification formed is very easily blockked up discharge device, both damaged discharge device and influenced equipment operation.

3) Since the pyrolysis process needs to be performed in an oxygen-free or oxygen-less environment, the sealing effect of the equipment is highly required. For the downdraft pyrolysis device, the raw materials can be divided into a sealing layer, a transition layer, a pyrolysis layer and a carbonization layer from top to bottom in the pyrolyzer, and the sealing layer and the transition layer are arranged above the pyrolysis layer, so that special consideration is not needed in the sealing during feeding. However, if special treatment is not carried out during carbon discharging, the pyrolysis reactor can be directly communicated with the external space, so that external air is flushed into the reactor, and the pyrolysis reaction process is seriously influenced. Meanwhile, the temperature of the biochar just generated is very high, and spontaneous combustion can occur when the biochar directly contacts air. The existing equipment generally realizes equipment sealing by additionally arranging devices such as an air seal device, a rotary valve and the like at a carbon outlet, but the general structure of the devices is more complex, the working effect is poorer, and the phenomenon of material blocking can be frequently caused. In the aspect of cooling, a condenser is sleeved outside the charcoal discharging device to cool the biochar generally, but the condensing effect of the method is poor, and the condenser is easy to have a fault after working for a long time.

Disclosure of Invention

The invention aims to provide rotary downdraft straw pyrolysis carbon gas co-production equipment to solve the problems in the prior art, the phenomena of slag bonding, bridging and arch bonding are not easy to occur in the pyrolysis and conveying processes of materials, and the carbon discharging tightness and stability of the system are greatly improved.

In order to achieve the purpose, the invention provides the following scheme:

the invention provides rotary downdraft straw pyrolysis carbon gas co-production equipment which comprises a pyrolysis cylinder, a carbon discharging device and a bracket for supporting the pyrolysis cylinder and the carbon discharging device; the pyrolysis cylinder comprises an upper section cylinder body, a middle section cylinder body and a lower section cylinder body which are sequentially arranged from top to bottom, wherein the middle section cylinder body can rotate by taking the axis of the cylinder as the center, a material pressing device is arranged at the top of the middle section cylinder body, a stirring rod and an air inlet rod are arranged on the inner wall of the middle section cylinder body, and external air is introduced into the middle section cylinder body through the air inlet rod; the carbon output device comprises a conical rotary cylinder, a spiral carbon conveying plate and a spiral carbon output cylinder; the spiral carbon conveying plate is fixedly connected in the conical rotary cylinder, a water inlet cavity is formed in the bottom of the conical rotary cylinder, a water inlet of the water inlet cavity is connected with a water tank through a water conveying pipe, and the bottom of the water inlet cavity is communicated with a feed inlet of the spiral carbon outlet cylinder; the spiral goes out the inside screw rod that is provided with of charcoal section of thick bamboo, the discharge end that the spiral goes out the charcoal section of thick bamboo is provided with toper play charcoal pipe, the pipe diameter that toper goes out the charcoal pipe diminishes along going out the charcoal direction gradually.

Preferably, a feed inlet is arranged at the top of the upper section of the cylinder body, an ignition port is arranged on one side of the top of the cylinder wall of the lower section of the cylinder body, and an exhaust pipe is arranged on the other side of the cylinder wall of the lower section of the cylinder body.

Preferably, a material loading level meter is arranged on the inner wall of the upper section cylinder, and a material unloading level meter is arranged on the inner wall of the middle section cylinder.

Preferably, the middle section barrel is driven to rotate by a first motor, the first motor is arranged on one side of the support, and a power output shaft of the first motor drives the middle section barrel to rotate by taking the axis of the barrel as a center through gear transmission.

Preferably, a double-roller carbon discharger is arranged in the lower-section cylinder and comprises a plurality of groups of meshed discharging rollers.

Preferably, the top cylinder body of the conical rotary cylinder is a flared cylinder body with the top diameter larger than the bottom diameter.

Preferably, the conical rotary drum is driven to rotate by a second motor, the second motor is arranged on one side of the support, and a power output shaft of the second motor drives the conical rotary drum to rotate around the axis of the drum body through gear transmission.

Preferably, the charcoal outlet of the conical charcoal outlet pipe is opposite to a charcoal collecting box, the bottom of the charcoal collecting box is provided with a water storage tank, and a bottom plate of the charcoal collecting box is provided with a water filtering hole.

Preferably, the barrel of the spiral charcoal tube is inclined upwards, the position of the feed inlet is lower than that of the discharge outlet, and the charcoal collecting box is arranged at the bottom of the conical charcoal tube.

Preferably, a lower water level meter is arranged on the inner wall of the water inlet cavity, and an upper water level meter is arranged on the inner wall of the conical rotary cylinder.

Compared with the prior art, the invention has the following beneficial technical effects:

1. the invention provides rotary downdraft straw pyrolysis carbon gas co-production equipment, which is a rotary internal heating pyrolysis reactor.A stirring rod and a material pressing device are arranged in a rotary cylinder, so that the heat transfer and mass transfer and fluidity of materials are enhanced through the rotation of a cylinder body, the problems of slag bonding and the like caused by poor fluidity and uneven heating of the materials are effectively solved, and the operation stability of a system and the quality of biochar are greatly improved.

2. According to the rotary downdraft straw pyrolysis carbon gas co-production equipment, the combined double-roller carbon discharger adopts multiple groups of meshed discharge rollers to form multiple gaps, the uniformity of downdraft airflow can be improved, the flow field of a pyrolysis area is improved, and the slagging risk is reduced; the spike-tooth type discharging roller can actively crush small blocks to form slag, and the risk of material blockage is effectively reduced.

3. The rotary downdraft straw pyrolysis carbon gas co-production equipment provided by the invention is provided with the conical rotary multistage sealing carbon discharging system, and the spiral carbon conveying plate is arranged in the conical carbon discharging device, so that the bridging and arching phenomena in the discharging process of straw biochar are overcome, and the carbon discharging stability of the system is improved; the spiral extrusion type charcoal outlet mechanism is matched with water seal charcoal outlet, so that charcoal outlet tightness in the whole process of starting and normal operation of the equipment is ensured. The conical rotation, the spiral extrusion and the initial water seal are combined, so that the carbon output sealing performance and stability of the system are greatly improved.

Drawings

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

FIG. 1 is a schematic structural view of a rotary downdraft straw pyrolysis carbon gas co-production apparatus according to the present invention;

in the figure: 1-a water tank; 2-a lower water level meter; 3-upper water level meter; 4-lower section of barrel; 5-an ignition port; 6-an air inlet rod; 7-stirring rod; 8-a level-lowering gauge; 9-upper section of cylinder; 10-a level gauge; 11-a feed inlet; 12-a swager; 13-middle section cylinder; 14-an exhaust pipe; 15-double-roller carbon remover; 16-spiral carbon conveying plate; 17-a conical rotary drum; 18-a conical carbon outlet pipe; 19-a carbon collecting box; 20-spirally discharging the carbon cylinder; 21-water conveying pipe; 22-bracket.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention aims to provide rotary downdraft straw pyrolysis carbon gas co-production equipment to solve the problems in the prior art.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

The rotary downdraft straw pyrolysis carbon gas co-production equipment in the embodiment comprises a pyrolysis cylinder, a carbon outlet device and a support for supporting the pyrolysis cylinder and the carbon outlet device, as shown in fig. 1; the pyrolysis cylinder comprises an upper section cylinder body 9, a middle section cylinder body 13 and a lower section cylinder body 4 which are sequentially arranged from top to bottom, the upper section cylinder body 9, the middle section cylinder body 13 and the lower section cylinder body 4 are all supported on a support through support rods, wherein a feed inlet 11 is formed in the top of the upper section cylinder body 9, the middle section cylinder body 13 can rotate around the axis of the cylinder, a material pressing device 12 is arranged at the top of the middle section cylinder body 13, a stirring rod 7 and an air inlet rod 6 are arranged on the inner wall of the middle section cylinder body 13, external air is introduced into the middle section cylinder body 13 through the air inlet rod 6, a carbon counter-roll discharger 15 is arranged in the lower section cylinder body 4 and consists of a plurality of groups of meshed discharge rolls, an ignition port 5 is formed in one side of the top of the cylinder wall of the lower section cylinder body 4, and an exhaust pipe 14 is arranged on the other side of the cylinder wall of the lower section cylinder body 4; the carbon discharging device comprises a conical rotary drum 17, a spiral carbon conveying plate 16 and a spiral carbon discharging drum 20; the conical rotary drum 17 is arranged at the bottom of the lower-section drum body 4, the spiral carbon conveying plate 16 is fixedly connected in the conical rotary drum 17, a water inlet cavity is arranged at the bottom of the conical rotary drum 17, a water inlet of the water inlet cavity is connected with the water tank 1 through a water conveying pipe 21, and the bottom of the water inlet cavity is communicated with the feed inlet 11 of the spiral carbon outlet drum 20; an extrusion screw is arranged in the spiral carbon outlet barrel 20, a conical carbon outlet pipe 18 is arranged at the discharge end of the spiral carbon outlet barrel 20, and the pipe diameter of the conical carbon outlet pipe 18 is gradually reduced along the carbon outlet direction.

In the embodiment, the inner wall of the upper section cylinder 9 is provided with a loading level indicator 10, and the inner wall of the middle section cylinder 13 is provided with a discharging level indicator 8; a lower water level meter 2 is arranged on the inner wall of the water inlet cavity, and an upper water level meter 3 is arranged on the inner wall of the conical rotary cylinder 17.

In this embodiment, the middle cylinder 13 is driven to rotate by a first motor, the first motor is disposed on one side of the bracket, and a power output shaft of the first motor drives the middle cylinder 13 to rotate around the axis of the cylinder through gear transmission.

In this embodiment, the top cylinder of the conical rotary cylinder 17 is a flared cylinder with a diameter of the top larger than that of the bottom.

In this embodiment, the conical rotary drum 17 is driven by the second motor, the second motor is disposed on one side of the bracket, and a power output shaft of the second motor drives the conical rotary drum 17 to rotate around the axis of the drum through gear transmission.

In this embodiment, the nozzle of the conical carbon outlet pipe 18 is opposite to a carbon collecting box 19, the bottom of the carbon collecting box 19 is provided with a water storage tank, and a bottom plate of the carbon collecting box 19 is provided with a water filtering hole; the barrel body of the spiral carbon outlet barrel 20 is obliquely and obliquely arranged, the position of the feed port 11 is lower than that of the discharge port, and the carbon collecting box 19 is arranged at the bottom of the conical carbon outlet pipe 18.

When the rotary downdraft straw pyrolysis carbon gas co-production equipment works, water in the water tank 1 is conveyed into the reactor through the water conveying pipe 21, water injection is stopped when the water level reaches the upper water level meter 3, the reactor is in a water sealing state at the moment, and water injection is continued when the water level is lower than the lower water level meter 2. The material enters the reactor from the feed inlet 11, is piled up in the barrel, stops feeding when the material level height reaches the material loading level indicator 10, and is flattened under the action of the material pressing device 12, and the material is compressed tightly. After the feeding is completed, ignition is performed through the ignition port 5, and the pyrolysis of the material is started. In the pyrolysis process, the stirring rod 7 plays a role in stirring materials, and the phenomenon of slagging of the materials is prevented. The air inlet rod 6 is responsible for providing oxygen in the pyrolysis process, so that the gas production rate of the equipment is improved. When the level is lower than the level meter 8, the feeding device starts to continue feeding. The biochar generated by pyrolysis is broken under the action of the roller carbon discharger 15 and falls into the conical rotary drum 17. The spiral carbon conveying plate 16 rotates together with the conical rotary drum 17 to convey the biochar in the drum downwards. When the biochar reaches the bottom, the biochar is conveyed outwards under the action of the spiral carbon outlet cylinder 20, the water-containing biochar is extruded and discharged under the action of the conical carbon outlet pipe 18, and part of water can be removed through extrusion, and the carbon outlet can be blocked, so that the sealing property is enhanced. The conical carbon outlet pipe 18 is connected with equipment through a flange, and the carbon outlet pipe with the corresponding conical degree can be replaced for biochar produced by different materials. The biochar falls through the conical carbon outlet pipe 18 into the carbon collection box 19. The bottom of the carbon collecting box 19 is provided with a bottom plate with a round hole and a water storage tank for separating and collecting water contained in the biochar.

The principle and the implementation mode of the invention are explained by applying specific examples, and the description of the above examples is only used for helping understanding the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In summary, this summary should not be construed to limit the present invention.

Claims

1. A rotary downdraft straw pyrolysis carbon gas co-production equipment is characterized in that: the device comprises a pyrolysis cylinder, a carbon discharging device and a bracket for supporting the pyrolysis cylinder and the carbon discharging device; the pyrolysis cylinder comprises an upper section cylinder body, a middle section cylinder body and a lower section cylinder body which are sequentially arranged from top to bottom, wherein the middle section cylinder body can rotate by taking the axis of the cylinder as a center, a material pressing device is arranged at the top of the middle section cylinder body, a stirring rod and an air inlet rod are arranged on the inner wall of the middle section cylinder body, and external air is introduced into the middle section cylinder body through the air inlet rod; the carbon discharging device comprises a conical rotary drum, a spiral carbon conveying plate and a spiral carbon discharging drum; the spiral carbon conveying plate is fixedly connected in the conical rotary cylinder, a water inlet cavity is formed in the bottom of the conical rotary cylinder, a water inlet of the water inlet cavity is connected with a water tank through a water conveying pipe, and the bottom of the water inlet cavity is communicated with a feed inlet of the spiral carbon outlet cylinder; the spiral goes out the inside screw rod that is provided with of charcoal section of thick bamboo, the discharge end that the spiral goes out the charcoal section of thick bamboo is provided with toper play charcoal pipe, the pipe diameter that toper goes out the charcoal pipe diminishes along going out the charcoal direction gradually.

2. The rotary downdraft straw pyrolysis carbon gas co-production apparatus as claimed in claim 1, wherein: the top of the upper section of the barrel body is provided with a feeding hole, one side of the top of the barrel wall of the lower section of the barrel body is provided with an ignition hole, and the other side of the barrel wall of the lower section of the barrel body is provided with an exhaust pipe.

3. The rotary downdraft straw pyrolysis carbon gas co-production apparatus as claimed in claim 1, wherein: and a material loading level meter is arranged on the inner wall of the upper section cylinder, and a material discharging level meter is arranged on the inner wall of the middle section cylinder.

4. The rotary downdraft straw pyrolysis carbon gas co-production apparatus as claimed in claim 1, wherein: the middle section barrel is driven to rotate through a motor I, the motor I is arranged on one side of the support, and a power output shaft of the motor I drives the middle section barrel to rotate by taking the axis of the barrel as the center through gear transmission.

5. The rotary downdraft straw pyrolysis carbon gas co-production apparatus as claimed in claim 1, wherein: the lower section cylinder is internally provided with a pair roller carbon discharger which comprises a plurality of groups of meshed discharging rollers.

6. The rotary downdraft straw pyrolysis carbon gas co-production apparatus as claimed in claim 1, wherein: the top barrel of the conical rotary drum is a flared barrel with the top diameter larger than the bottom diameter.

7. The rotary downdraft straw pyrolysis carbon gas co-production apparatus as claimed in claim 1, wherein: the conical rotary drum is driven to rotate by a second motor, the second motor is arranged on one side of the support, and a power output shaft of the second motor drives the conical rotary drum to rotate by taking the axis of the drum body as the center through gear transmission.

8. The rotary downdraft straw pyrolysis carbon gas co-production apparatus as claimed in claim 1, wherein: the charcoal outlet of the conical charcoal outlet pipe is opposite to a charcoal collecting box, the bottom of the charcoal collecting box is provided with a water storage tank, and a bottom plate of the charcoal collecting box is provided with a water filtering hole.

9. The rotary downdraft straw pyrolysis carbon gas co-production apparatus as claimed in claim 8, wherein: the barrel body of the spiral carbon outlet barrel is obliquely and obliquely inclined, the position of the feeding hole is lower than that of the discharging hole, and the carbon collecting box is arranged at the bottom of the conical carbon outlet pipe.

10. The rotary downdraft straw pyrolysis carbon gas co-production apparatus as claimed in claim 1, wherein: the inner wall of the water inlet cavity is provided with a lower water level gauge, and the inner wall of the conical rotary cylinder is provided with an upper water level gauge.