CN112473611B

CN112473611B - Reactor for researching biomass three-component pyrolysis interaction reaction

Info

Publication number: CN112473611B
Application number: CN202011247273.8A
Authority: CN
Inventors: 曾阔; 李硕; 陈汉平; 杨海平; 李俊; 杨心怡; 钟典; 左宏杨; 汪璐文; 张欣; 刘晴川
Original assignee: Wuhan Juyang New Energy Technology Co ltd; Huazhong University of Science and Technology
Current assignee: Wuhan Juyang New Energy Technology Co ltd; Huazhong University of Science and Technology
Priority date: 2020-11-10
Filing date: 2020-11-10
Publication date: 2022-03-18
Anticipated expiration: 2040-11-10
Also published as: CN112473611A

Abstract

The invention belongs to the field of biomass fast pyrolysis, and particularly discloses a reactor for researching biomass three-component pyrolysis interaction reaction, which comprises a carrier gas container, a test tube, a fixed bed hearth, a condensing device and an air bag, wherein: the carrier gas container, the test tube, the condensing device and the gas bag are sequentially connected, and the fixed bed hearth is arranged on the outer side of the test tube; the test tube is internally provided with a slide way and a plurality of gaskets meshed with the slide way; the gasket is in sliding contact with the slide way, and is provided with through holes and grooves, the through holes are used for carrier gas circulation, and the grooves are used for placing reactants; be provided with stop device on the test tube, this stop device is used for restricting the axial position of gasket in the test tube. The invention can quickly mix the volatile matters generated by different components and generate an interactive reaction under the condition of ensuring that the volatile matters are timely taken away from the reactor, effectively inhibits the secondary reaction of biomass pyrolysis, and has great significance for researching the formation mechanism of the heavy components of the biomass pyrolysis oil.

Description

Reactor for researching biomass three-component pyrolysis interaction reaction

Technical Field

The invention belongs to the field of biomass fast pyrolysis, and particularly relates to a reactor for researching biomass three-component pyrolysis interaction reaction.

Background

In recent years, crude oil and petroleum resources are increasingly in short supply, and the development of the rapid pyrolysis of biomass to prepare bio-oil is imperative. Unlike the first generation of biomass-to-fuel ethanol, which utilizes only sugars of biomass, the second generation of biomass focuses on the utilization of full components. However, the biomass three components, particularly lignin and hemicellulose, have large molecular weight and amorphous structure, and have interactive reaction in pyrolysis, which brings great difficulty in understanding various components of the pyrolysis bio-oil, particularly heavy components. At present, a great deal of research has been conducted on the mechanism of producing bio-oil by fast pyrolysis of biomass from a single component, but it is far from sufficient to explore the components of bio-oil from a single component only, and it is also necessary to explore their interaction.

For the fast pyrolysis of biomass, the main objective is to improve the liquid yield, and the existing ampoule bottle of the apparatus has the inherent defect that the retention time of volatile matters in the reactor is too long due to the closed environment, so that secondary reaction occurs to form coke, which is not favorable for the research of the whole components, especially heavy components of the biomass pyrolysis oil, so that the development of a novel reactor is urgently needed to effectively inhibit the secondary reaction of the biomass pyrolysis, thereby improving the yield of the biomass oil.

Disclosure of Invention

Aiming at the defects or the improvement requirements of the prior art, the invention provides a reactor for researching biomass three-component pyrolysis interaction reaction, and aims to quickly mix volatile matters generated by different components and carry out interaction reaction under the condition of ensuring that the volatile matters are timely taken away from the reactor through the design of a reaction test tube and an internal gasket thereof, so that the reactor is different from solid/liquid phase interaction reaction when two components are directly contacted, and the secondary reaction of biomass pyrolysis is effectively inhibited.

In order to achieve the above object, the present invention provides a reactor for researching biomass three-component pyrolysis interaction reaction, comprising a carrier gas container, a test tube, a fixed bed hearth, a condensing device and an air bag, wherein:

the carrier gas container, the test tube, the condensing device and the gas bag are sequentially connected, and the fixed bed hearth is arranged on the outer side of the test tube; the test tube is internally provided with a slide way and a plurality of gaskets meshed with the slide way; the gasket is in sliding contact with the slide way, and is provided with through holes and grooves, the through holes are used for carrier gas circulation, and the grooves are used for placing reactants; be provided with stop device on the test tube, this stop device is used for the restriction the axial position of gasket in the test tube.

Preferably, the plurality of spacers have the same shape, a through hole is formed in the middle of each spacer, and an annular groove is formed around each through hole.

Preferably, the number of the gaskets is two, the two gaskets are in the same shape, a through hole is formed in the middle of each gasket, a plurality of inclined through holes and grooves are alternately formed in the periphery of each through hole, and the two gaskets are arranged in a staggered mode, so that the inclined through hole of one gasket corresponds to the groove of the other gasket in the axial direction of the test tube.

More preferably, the center line of the inclined through hole is inclined, and the included angle between the center line of the inclined through hole and the surface of the gasket is 45-75 degrees.

Preferably, the limiting device is a cross-shaped needle-shaped limiting rod which penetrates through the wall surface of the test tube to limit the position of the gasket.

Preferably, the test tube is provided with four sets of limiting holes, and each set of limiting holes is used for a pair of needle-shaped limiting rods to pass through.

As further preferred, four groups spacing holes set gradually, wherein, the spacing hole of first group and the spacing hole of second group to and the spacing distance between the hole of second group and the spacing hole of third group are the radius of test tube, the spacing distance between the hole of third group and the spacing hole of fourth group is the diameter of test tube.

Preferably, both ends of the test tube penetrate through the fixed bed hearth, and sealing rings are arranged at the upper and lower contact positions of the test tube and the fixed bed hearth.

Preferably, a valve is provided between the carrier gas container and the test tube, and a three-way valve is provided between the condensing unit and the air bag.

More preferably, the test tube is a quartz glass test tube.

Generally, compared with the prior art, the above technical solution conceived by the present invention mainly has the following technical advantages:

1. according to the invention, through the design of the reaction test tube and the internal gasket thereof, under the condition that volatile components are timely taken away from the reactor, the volatile components generated by different components can be quickly mixed and subjected to an interaction reaction, so that the reaction is different from a solid/liquid phase interaction reaction when the two components are directly contacted, the secondary reaction of biomass pyrolysis can be effectively inhibited, and the reaction has great significance for researching the formation mechanism of the heavy components of biomass pyrolysis oil.

2. The invention satisfies the principle of small reactant dosage when researching the reaction mechanism, and the reactants are uniformly dispersed and arranged by the gasket, so that the reaction volatile components are fully and uniformly mixed, and the interactive reaction is favorably carried out; in addition, the invention not only can independently research the gas-phase interaction, but also can further research the comprehensive influence of gas-solid interaction, solid-liquid interaction and gas-gas interaction, and has the advantages of simple operation, high flexibility, wide adaptability and the like.

3. The invention is designed for the structure of the gasket, fully utilizes the principle that static pressure reduces entrainment effect on airflow and tangentially arranges a flow passage to enable reaction pyrolysis volatile components to generate spin, simultaneously eliminates the influence of gas-solid interaction, and has great effect on researching the gas-phase interaction mechanism of three components of biomass. Specifically, the invention designs two gaskets, wherein the first scheme skillfully utilizes the principle that total pressure is equal to dynamic pressure and static pressure, and the entrainment effect is generated by the characteristic that the flow velocity of a middle hole is large and the pressure intensity is smaller than the peripheral pressure intensity to complete the mixing of two volatile components; according to the second scheme, the tangential circle is used for arrangement, the volatile component spinning is formed, the influence of earth surface deflection force (Coriolis force) is considered, the direction of the inclined through hole of the gasket is that the northern hemisphere is inclined along the clockwise direction, the southern hemisphere is inclined along the anticlockwise direction, and the mixing degree of the volatile component is further increased on the basis of the arrangement of the original tangential circle.

4. According to the invention, the integrated slide way is additionally arranged on the inner wall of the test tube, the gasket groove is meshed with the slide way, so that the relative fixation of the gaskets in the circumferential direction is realized, the gaskets are not locked in the axial direction, the distance between the two gaskets and the relative position of the gaskets in the hearth can be flexibly adjusted in the axial direction, and the design of the slide way is favorable for accurately adjusting the staggered angle of the gaskets.

5. The limiting device for fixing the gasket is realized by drilling four crossed limiting holes in the wall of the test tube and inserting the needle-shaped limiting rod, is simple and convenient to operate and has small influence on airflow disturbance; simultaneously through installing stop device additional, the gasket interval can change between test tube radius, test tube diameter, 1.5 times test tube diameter and twice test tube diameter, what can be better is applicable to multiple operating mode.

Drawings

FIG. 1 is a schematic diagram of a reactor structure for studying biomass three-component pyrolysis interaction reaction according to an embodiment of the invention;

FIGS. 2 (a) and (b) are a plan view and a perspective view of a test tube of silica glass according to an embodiment of the present invention;

FIGS. 3 (a) and (b) are a top view and a perspective view of a first embodiment of a gasket according to the present invention;

FIGS. 4 (a) and (b) are a top view and a perspective view of a second embodiment of a gasket according to the present invention;

FIG. 5 is a simplified model of the gasket of FIG. 4 showing the direction of air flow through the corresponding angled through hole;

FIG. 6 is a schematic diagram of the position of the limiting hole on the wall of the high temperature-resistant quartz glass test tube according to the embodiment of the present invention.

The same reference numbers will be used throughout the drawings to refer to the same or like elements or structures, wherein: 1-carrier gas container, 2-valve, 3-conduit, 4-test tube, 5-fixed bed hearth, 6-slideway, 7-sealing ring, 8-condensing unit, 9-air bag, 10-gasket, 11-three-way valve, 12-position limiter.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

The reactor for researching biomass three-component pyrolysis interaction provided by the embodiment of the invention is shown in fig. 1, and comprises a carrier gas container 1, a test tube 4, a fixed bed hearth 5, a condensing device 8 and an air bag 9, wherein:

the carrier gas container 1, the test tube 4, the condensing device 8 and the air bag 9 are arranged in sequence and are communicated through the guide pipe 3; a valve 2 is arranged between the carrier gas container 1 and the test tube 4, and a three-way valve 11 is arranged between the condensing device 8 and the air bag 9; fixed bed furnace 5 sets up the 4 outsides of test tube, the both ends of test tube 4 are all passed fixed bed furnace 5 to in holding and removing the adding of test tube 4, and contact department all is provided with sealing washer 7 about test tube 4 and fixed bed furnace 5.

Specifically, the condensing device 8 is a fractional condensing device, and is used for condensing and collecting pyrolysis volatile components; pipe 3 is high temperature resistant glass pipe, and test tube 4 is high temperature resistant quartz glass test tube, and this quartz glass test tube can build a little environment in the fixed bed of high temperature, avoids its direct winding resistance wire on the test tube to produce danger and carrier gas that high temperature environment caused the experimenter to the excessive dilution of pyrolysis gas.

6 raised slideways 6 are uniformly distributed on the inner wall of the test tube 4 at intervals of 60 degrees in the circumferential direction, as shown in fig. 2, and a plurality of gaskets 10 meshed with the slideways 6 are arranged, wherein the gaskets 10 can slide on the slideways 6, and the slideways 6 enable the gaskets 10 to be fixed in the circumferential direction and only move along the axial direction; meanwhile, the gasket 10 is strictly attached to the inner wall of the test tube 4, the shape is adaptive, the outer wall of the test tube can be marked with dimensions, and the distance between gaskets is conveniently recorded and adjusted, so that the optimal mixing distance and the degree of interaction are calculated; the gaskets 10 are provided with through holes and grooves, the through holes are used for carrier gas circulation, and the grooves are used for placing reactants; the test tube 4 is provided with a limiting device which is used for limiting the axial position of the gasket 10 in the test tube 4.

Furthermore, the gasket is divided into two schemes, wherein the first scheme realizes the rapid mixing of the pyrolysis volatile components of the biomass through the driving of the carrier gas, and the second scheme forms small vortexes above the gasket through inclined through holes reasonably distributed in the gasket so as to realize the self-mixing of the volatile components; the pad has a plurality of pads for placing different reactants, and two pads are taken as an example to illustrate, specifically:

the first scheme is as follows: as shown in fig. 3, the two gaskets have the same shape, a through hole is formed in the middle of each gasket, and an annular groove is formed around each through hole; it can be seen from fig. 2 that when the carrier gas flows through the first gasket, due to the reduction of the flow area, a certain acceleration effect is inevitably generated at the central opening, so that the static pressure near the hole is reduced, the pyrolysis volatile components have a tendency of inward entrainment, and the mixing of the pyrolysis volatile components and the carrier gas is promoted.

Scheme II: as shown in fig. 4, the two gaskets have the same shape, a through hole is formed in the middle of each gasket, three inclined through holes and three grooves are uniformly and alternately formed in the periphery of the through hole, reactants are placed in the three grooves which are uniformly distributed at 120 degrees along the circumferential direction, the inclined through holes are inclined along the tangential direction, a simplified model of the inclined direction is shown in fig. 5, the inclined angle is alpha, airflow passing through the gaskets forms a vortex along the clockwise direction, the strength of the vortex is further enhanced by considering the action of the turning force, and carrier gas and volatile are better mixed; the second gasket and the first gasket are arranged in a staggered mode, the staggered angle is 60 degrees, even if the inclined through holes of the second gasket correspond to the grooves of the first gasket in the axial direction, after the air flow passes through the first gasket at the lower part, the air flow can pass through the inclined through holes in the vertical direction, namely, the inclined through holes can pass through the inclined through holes except the middle hole, the inclined through holes must rotate by at least 60 degrees, the initial speed of the air flow in the tangential direction is provided, conditions are provided for stronger mixing action of the air flow passing through the second gasket at the upper part, the necessary retention time required by gas-phase interaction can be shortened, the air flow after the reaction is condensed in the grading condensing device, and the non-condensable gas is collected by the air bag. Specifically, the upper gasket and the lower gasket are arranged in a staggered manner through six slideways which are uniformly distributed along the circumference of 60 degrees and are positioned on the inner wall of the test tube; the three inclined through holes and the three grooves distributed along the circumference can be obliquely arranged. Preferably, the included angle alpha between the central line of the inclined through hole and the surface of the gasket is 45-75 degrees; meanwhile, the design of the gasket takes the influence of the yaw force into consideration, and the direction of the inclined hole of the gasket needs to be combined with the position of the located north-south hemisphere.

Further, stop device is the criss-cross needle-like spacing stick, and this needle-like spacing stick passes the test tube wall to restrict the gasket position, and this needle-like spacing stick need avoid slide department to set up. Furthermore, four groups of limiting holes are formed in the test tube, and each group of limiting holes is used for a pair of needle-shaped limiting rods to penetrate through; as shown in fig. 6, four groups spacing holes set gradually, wherein, the spacing hole of first group spacing hole and second group, and the axial distance between spacing hole of second group and the spacing hole of third group is the radius R of test tube, the axial distance between the spacing hole of third group and the spacing hole of fourth group does the diameter D of test tube, then can adjust the interval of two gaskets as required, two gasket intervals if place on the spacing hole of first group spacing hole and second group are the test tube radius, two gasket intervals of placing on the spacing hole of first group spacing hole and third group are the test tube diameter, place two gasket intervals on the spacing hole of second group spacing hole and fourth group be 1.5 times's test tube diameter, place two gasket intervals on the spacing hole of first group spacing hole and fourth group spacing hole be twice test tube diameter.

When the pyrolysis reactor is adopted for biomass component interaction reaction mechanism research, firstly, lignin and cellulose (or hemicellulose) are respectively filled in an upper gasket and a lower gasket, and the gaskets are initially positioned at the lower positions of test tubes and are not positioned in a hearth, so that the phenomenon that reactants are subjected to pyrolysis reaction in advance in the process of heating the hearth to a specified temperature is avoided; then sequentially sending the upper and lower gaskets filled with lignin and cellulose (or hemicellulose) into a designated position along a slideway, inserting two needle-shaped limiting rods into the test tube along a limiting device hole for limiting, and fixing the positions of the gaskets; at the moment, the valve 2 and the three-way valve 11 are opened to enable airflow to flow out along the lower pipeline, carrier gas enters each reaction pipeline to discharge air, and then the two valves are closed; opening the fixed bed, raising the temperature of the hearth to 600 ℃, then opening the valve 2 and the three-way valve 11, leading the airflow into the air bag, rapidly inserting the high-temperature-resistant quartz glass test tube into the hearth, rapidly pyrolyzing lignin and cellulose (or hemicellulose) on the two gaskets, leading the pyrolysis volatile matter to rise while being mixed under the driving of the carrier gas, completing the reaction when reaching the outlet of the hearth, and entering the grading condensing device 8 along the high-temperature-resistant glass pipeline 3 for condensation, and collecting the generated non-condensable gas into the air bag.

The invention is not limited to two gaskets, and the number of the gaskets can be adjusted according to actual needs, so that a detailed reaction mechanism among three components is obtained. For the comprehensive influence of gas-solid interaction, solid-liquid interaction and gas-gas interaction, the three components can be placed together for pyrolysis reaction through the first gasket scheme, and the result is compared with the result of single gas-gas interaction.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A reactor for studying biomass three-component pyrolysis interaction reaction, which is characterized by comprising a carrier gas container (1), a test tube (4), a fixed bed hearth (5), a condensing device (8) and an air bag (9), wherein:

the carrier gas container (1), the test tube (4), the condensing device (8) and the air bag (9) are sequentially connected, and the fixed bed hearth (5) is arranged on the outer side of the test tube (4); a slide way (6) and a plurality of gaskets (10) meshed with the slide way (6) are arranged in the test tube (4); the gasket (10) is in sliding contact with the slide way (6), through holes and grooves are formed in the gasket (10), the through holes are used for carrier gas circulation, and the grooves are used for placing reactants; the test tube (4) is provided with a limiting device (12), and the limiting device (12) is used for limiting the axial position of the gasket (10) in the test tube (4);

the gasket (10) has two specific arrangement forms:

the first method comprises the following steps: the gaskets (10) are the same in shape, a through hole is formed in the middle of each gasket (10), and annular grooves are formed around the through holes;

and the second method comprises the following steps: the test tube is characterized in that the number of the gaskets (10) is two, the shape of each gasket is the same, a through hole is formed in the middle of each gasket (10), a plurality of inclined through holes and grooves are alternately formed in the periphery of each through hole, and the two gaskets are arranged in a staggered mode, so that the inclined through hole of one gasket corresponds to the groove of the other gasket in the axial direction of the test tube;

the limiting device (12) is a cross needle-shaped limiting rod which penetrates through the wall surface of the test tube to limit the position of the gasket; four groups of limiting holes are formed in the test tube (4), and each group of limiting holes is used for a pair of needle-shaped limiting rods to penetrate through; four sets of spacing hole sets gradually, wherein, the spacing hole of first group and second group to and the spacing distance between the hole of second group and the spacing hole of third group is the radius of test tube (4), the spacing distance between the hole of third group and the spacing hole of fourth group is the diameter of test tube (4).

2. The reactor for researching biomass three-component pyrolysis interaction reaction of claim 1, wherein the central line of the inclined through hole is inclined, and the included angle between the central line of the inclined through hole and the surface of the gasket is 45-75 degrees.

3. The reactor for researching biomass three-component pyrolysis interaction reaction as claimed in claim 1, wherein both ends of the test tube (4) pass through the fixed bed furnace (5), and sealing rings (7) are arranged at the upper and lower contact positions of the test tube (4) and the fixed bed furnace (5).

4. The reactor for studying biomass three-component pyrolysis interaction reaction as claimed in claim 1, wherein a valve (2) is arranged between the carrier gas container (1) and the test tube (4), and a three-way valve (11) is arranged between the condensing device (8) and the air bag (9).

5. Reactor for investigating a biomass three-component pyrolysis interaction reaction according to any one of claims 1 to 4, characterised in that the test tube (4) is a quartz glass test tube.