A small self-heating reaction device

Abstract

The application belongs to the technical field of synthetic gas reaction device, and particularly relates to a small self-heating reaction device. The device comprises a heat preservation tank, a heat carrier tank is arranged in the heat preservation tank, the top end of the heat carrier tank is sealingly welded with the top of the heat preservation tank through a first sealing sleeve pipe, the bottom end of the heat carrier tank is sealingly welded with the bottom of the heat preservation tank through a second sealing sleeve pipe, a vacuum interlayer is arranged between the heat carrier tank and the heat preservation tank, a vertical through hole is arranged in the center of the heat carrier tank, a reaction tube is arranged in the vertical through hole, a heating rod and a first temperature measuring tube are vertically arranged in the heat carrier tank, a first temperature measuring element is arranged in the first temperature measuring tube and close to the top of the heat carrier tank, a second temperature measuring element is arranged in the first temperature measuring tube and close to the bottom of the heat carrier tank, an upper heating ring is arranged on the inner top wall of the heat preservation tank, and a lower heating ring is arranged on the inner bottom wall of the heat preservation tank. The vacuum interlayer has good sealing performance, the reaction tube can be individually disassembled, and the reaction tube can be individually replaced after being damaged, so that the cost can be reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of synthetic gas reaction device, and particularly relates to a small self-heating reaction device. BACKGROUND

[0002] Gasification technology can convert low-grade solid fuels such as coal and biomass into high-grade synthesis gas, which is a key technology for developing bulk chemicals or liquid fuel synthesis. Biomass energy accounts for 14% of global primary energy consumption, not only in terms of total quantity, but also in terms of wide distribution, renewability, low pollution and net zero CO2 emissions. Its gasification technology has developed rapidly since the 1980s. However, the development of its gasification technology has been affected by the low calorific value of biomass, high tar yield and unstable supply. Coal gasification has a history of more than 100 years, and the technology is relatively mature. The main problem of its gasification technology is the incomplete conversion of coke caused by slow kinetics, which reduces the gasification efficiency and leads to the emission of fine particles. Coal and biomass co-gasification not only has important significance for alleviating energy crisis and reducing greenhouse effect, but also can make good use of each other's advantages to overcome their own shortcomings. On the one hand, the high temperature environment generated by coal gasification can increase the gasification temperature of biomass and promote the further decomposition of biomass tar; on the other hand, the alkali / alkaline earth metal substances released by biomass in the hot environment can catalyze the gasification reaction of coal coke and improve its conversion rate. However, the low energy density of biomass raw materials and the corresponding low combustion enthalpy value will lower the temperature of the gasification furnace and may reduce the energy efficiency of the system.

[0003] The study of heat distribution and variation in the physical and chemical changes of the system has an important influence on the successful and safe scale-up of chemical processes. The process heat effect can not only be used to calculate the adiabatic temperature rise to provide an evaluation of the most severe reaction conditions in the adiabatic / quasi- adiabatic reactor reaction process, but also can guide the chemical production process to find the appropriate process conditions to obtain the maximum energy utilization efficiency. For example, the gasification temperature is the most important factor affecting the gasification intensity, gasification efficiency and gas quality. The content of effective components in the product gas mainly depends on the reduction reaction of CO2 and the decomposition reaction of water vapor. The increase of the bed temperature is conducive to the progress of these two reactions, which can not only improve the gas production but also improve the gas quality. However, if the bed temperature is too high, it will increase the heat loss and the sensible heat loss carried away by the product gas. Moreover, the ash generated after gasification will soften and melt, resulting in serious slagging phenomenon, which will affect the stable operation of the gasifier. The energy absorption and energy release in the thermochemical conversion process of raw materials with different properties will be different due to the difference in their physical and chemical structure composition. The calculation simulation of the reactor size and heat transfer problem all need to be based on the process energy balance. Therefore, the study of the heat absorption and release characteristics of the reaction raw materials in the thermal conversion process has important practical significance for guiding the optimization of energy supply and controlling the reaction conditions. However, the current laboratory scale external heating reactor cannot accurately control and measure the heat input into the reaction system, which makes it have obvious limitations in the study of chemical reaction heat.

[0004] For the reaction carried out on the laboratory scale reaction device, the heat absorbed or released is very limited, and the influence of external factors on the temperature in the reactor is often greater than the temperature change of the system caused by the reaction itself, therefore, the relationship between the heat absorption or release of the reaction itself and the temperature needs to be studied under the adiabatic condition or the approximate adiabatic condition. The current design and development of the reactor are still the focus and difficulty of scientific workers at home and abroad, especially the adiabatic reactor. Chinese patent CN101961628A discloses a small and medium-sized adiabatic reactor, although the reactor uses vacuum technology to obtain good adiabatic effect, but since the vacuum adiabatic layer is composed of a jacket and a reactor, the sealing requirement at the contact part of the reactor and the jacket is higher during the vacuumizing process. Although the sealing at low temperature is relatively easy to realize, but the sealing effect at high temperature is not necessarily good. Chinese patent CN205109599U aims at the above-mentioned defects, and provides a small fixed bed adiabatic reactor with an integrated structure of the reactor and the jacket, which avoids the requirement of high-temperature sealing technology at the contact part of the reactor and the jacket. However, the integrated structure makes the reactor not be able to be disassembled, when a part (such as a sieve plate) in the reactor is damaged, the whole reactor can only be replaced, which greatly increases the investment of the equipment and cannot meet the requirement of long-term repeated use of the reactor. In addition, since the heat cannot be continuously provided for the reaction under the adiabatic condition, the above two adiabatic reactors can only be used to study the exothermic chemical reaction process, and cannot be used to study the system with endothermic reaction, which greatly limits the application range of them. SUMMARY

[0005] In view of the problems existing in the prior art, a small self-heating type reaction device is disclosed in the present application, and the following technical solutions are specifically disclosed:

[0006] The small self-heating type reaction device comprises a heat preservation tank, a heat carrier tank is arranged in the heat preservation tank, the top end of the heat carrier tank is sealingly welded with the top of the heat preservation tank through a first sealing sleeve pipe, the bottom end of the heat carrier tank is sealingly welded with the bottom of the heat preservation tank through a second sealing sleeve pipe, a vacuum interlayer is arranged between the heat carrier tank and the heat preservation tank, a vertical through hole is arranged in the center of the heat carrier tank, a reaction tube is arranged in the vertical through hole, a reaction bed is arranged in the reaction tube, the top end of the reaction tube is communicated with a first communication pipe and a second communication pipe, the first communication pipe and the second communication pipe respectively extend out of the heat preservation tank through the top wall of the heat preservation tank, the bottom end of the reaction tube downwardly penetrates the bottom wall of the heat preservation tank and is communicated with a third communication pipe, a heating rod and a first temperature measuring pipe are vertically arranged in the heat carrier tank, a first temperature measuring element is arranged in the first temperature measuring pipe at a position close to the top of the heat carrier tank, a second temperature measuring element is arranged in the first temperature measuring pipe at a position close to the bottom of the heat carrier tank, an upper heating ring is arranged on the inner top wall of the heat preservation tank, and a lower heating ring is arranged on the inner bottom wall of the heat preservation tank.

[0007] Further, the heat preservation tank is composed of the upper heat preservation plate, the lower heat preservation plate and the side heat preservation plate, the upper heating ring is fixedly connected to the lower surface of the upper heat preservation plate, and the lower heating ring is fixedly connected to the upper surface of the lower heat preservation plate.

[0008] Further, the bottom end of the heat preservation tank is provided with the air exhaust pipe communicated with the vacuum interlayer, and the end of the air exhaust pipe away from the heat preservation tank is sequentially communicated with the pressure gauge, the valve and the vacuum pump.

[0009] Further, the bottom end of the reaction tube located outside the heat preservation tank is sleeved with the heat preservation layer.

[0010] Further, the second temperature measuring tube is vertically arranged in the reaction tube, and a plurality of third temperature measuring elements are sequentially and spacedly arranged in the second temperature measuring tube from top to bottom.

[0011] Further, the heat carrier adopts one of quartz sand, silicon carbide and ceramic ball.

[0012] Compared with the prior art, the present application has the following beneficial effects:

[0013] In the present application, the heat carrier tank is sealed and welded with the heat preservation tank through the first sealing sleeve pipe and the second sealing sleeve pipe, so that a sealed space is formed between the heat preservation tank and the heat carrier tank, and therefore the sealing property can be reliably guaranteed. The heat carrier tank is centrally provided with a vertical through hole, and the reaction tube is installed in the vertical through hole and can be individually disassembled and replaced after damage, so that the cost can be reduced. In addition, the heat carrier tank and the heating rod can be arranged to continuously provide heat for the reaction under the adiabatic condition, so that the present application can be used not only for studying the exothermic chemical reaction process, but also for studying the system with endothermic reaction. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is a structural schematic view of Example 1.

[0015] Figure 2 It is a structural schematic view of Example 2.

[0016] Figure 3 It is a structural schematic view of Example 3.

[0017] 1-reaction tube, 2-second temperature measuring tube, 3-first temperature measuring tube, 4-heat carrier, 5-heating rod, 6-vacuum interlayer, 7-side heat preservation plate, 8-upper heat preservation plate, 9-lower heat preservation plate, 10-heat preservation layer, 11-upper heating ring, 12-lower heating ring, 13-first temperature measuring element, 14-second temperature measuring element, 15-third temperature measuring element, 16-vacuum pump. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0019] Embodiment 1

[0020] With reference to Figure 1 A small self-heating reaction device comprises a heat preservation tank, a heat carrier tank is arranged in the heat preservation tank, the top end of the heat carrier tank is sealingly welded with the top of the heat preservation tank through a first sealing sleeve, the bottom end of the heat carrier tank is sealingly welded with the bottom of the heat preservation tank through a second sealing sleeve, a vacuum interlayer 6 is arranged between the outer wall of the heat carrier tank and the inner wall of the heat preservation tank, a vertical through hole is arranged in the center of the heat carrier tank, a reaction tube 1 is arranged in the vertical through hole, a reaction bed is arranged in the reaction tube 1, the top end of the reaction tube 1 is communicated with a first communication pipe and a second communication pipe, the first communication pipe and the second communication pipe respectively extend out of the heat preservation tank through the top wall of the heat preservation tank, the bottom end of the reaction tube 1 downwardly penetrates the bottom wall of the heat preservation tank and is communicated with a third communication pipe, a heating rod 5 and a first temperature measuring pipe 3 are vertically arranged in the heat carrier tank, the bottom end of the heating rod 5 is inserted into the heat carrier tank, the top end of the heating rod 5 penetrates the top wall of the heat preservation tank and is connected with a power supply, a first temperature measuring element 13 is arranged in the first temperature measuring pipe 3 at a position close to the top of the heat carrier tank, a second temperature measuring element 14 is arranged in the first temperature measuring pipe 3 at a position close to the bottom of the heat carrier tank, an upper heating ring 11 is arranged on the inner top wall of the heat preservation tank, and a lower heating ring 12 is arranged on the inner bottom wall of the heat preservation tank.

[0021] In the embodiment, the reaction tube 1 is an updraft fixed bed reaction tube, the reaction bed in the reaction tube 1 is a fixed bed, the first communication pipe is used as a raw material inlet to input solid fuel into the reaction tube 1, the second communication pipe is used as a gas outlet to discharge the generated gas, and the third communication pipe is used as a gasification agent inlet to input the gasification agent into the reaction tube 1.

[0022] The raw material is combusted / gasified in the reaction tube 1, the high-temperature heat carrier 4 heated by the heating rod 5 in the heat carrier tank serves as an initial heat source of the reaction, and the vacuum interlayer 6 plays a role of heat insulation to provide an adiabatic environment for the chemical reaction in the heat carrier 4 and the reaction tube 1.

[0023] In the embodiment, the heat preservation tank is sealingly welded by an upper heat preservation plate 8, a lower heat preservation plate 9 and side heat preservation plates 7, the upper heating ring 11 is fixedly connected to the lower surface of the upper heat preservation plate 8, and the lower heating ring 12 is fixedly connected to the upper surface of the lower heat preservation plate 9.

[0024] In this embodiment, the bottom end of the heat preservation tank is provided with an exhaust pipe communicated with the vacuum interlayer 6, and the exhaust pipe far away from the heat preservation tank is sequentially communicated with a pressure gauge, a valve and a vacuum pump 16, so that the vacuum interlayer 6 can be vacuumized by the vacuum pump 16.

[0025] In this embodiment, the bottom end of the reaction tube 1 is sleeved with a heat preservation layer 10 at a position outside the heat preservation tank, so as to play a heat insulation role.

[0026] In this embodiment, a vertical second temperature measuring tube 2 is arranged in the reaction tube 1, and a plurality of third temperature measuring elements 15 are sequentially and spacedly arranged in the second temperature measuring tube 2 from top to bottom, for monitoring the temperature at different positions in the reaction tube 1.

[0027] In this embodiment, the heat carrier 4 is one of quartz sand, silicon carbide and ceramic ball.

[0028] The vacuum pump 16 is first opened to create a vacuum before the reaction starts. When the vacuum in the vacuum interlayer 6 reaches a constant limit, the valve on the vacuum pump is closed, and the vacuum in the vacuum interlayer 6 is greatly weakened, thus reducing the heat loss of the heat carrier 4 and the reaction tube 1 due to heat conduction and heat convection with the outside. The power supply to the heating rod 5 is turned on to start heating the heat carrier 4, while the first temperature measuring element 13 and the second temperature measuring element 14 in the first temperature measuring tube 3 detect the temperature near the first sealing sleeve and the second sealing sleeve of the heat carrier tank, respectively, to control the on-off of the upper heating ring 11 and the lower heating ring 12 in series, respectively. The heating temperature of the upper heating ring 11 and the lower heating ring 12 always tracks the temperature detected by the first temperature measuring element 13 and the second temperature measuring element 14, respectively. The first sealing sleeve and the second sealing sleeve at the connection between the heat carrier tank and the heat preservation tank are the only access for the reaction tube 1 and the heat carrier 4 to dissipate heat to the outside through heat conduction. The temperature tracking of these two places makes the inner and outer temperatures approximately equal, thus preventing the heat loss of the heat carrier 4 and the reaction tube 1 through heat conduction to the maximum extent. The outer surface of the heat carrier tank and the inner surface of the heat preservation tank can be made of mirror surface material or directly electroplated, thus increasing the reflection efficiency of the surface and making the radiation heat loss negligible. Through the above measures, the three ways of heat transfer between the reactor and the outside (conduction, convection, and radiation) are maximally blocked, and the heat insulation accuracy of the reactor is greatly improved. When the temperature of the heat carrier 4 reaches a certain target value, the raw material is added from the top of the reaction tube 1 to the sieve plate in the tube, which is rapidly heated in the high-temperature environment. At the same time, a gasification agent is introduced from the bottom of the reaction tube 1, which interacts with the raw material on the sieve plate to produce a combustion / gasification reaction. In this reaction, the heat released by the combustion reaction supplies the endothermic chemical reaction in the gasification reaction, thus realizing a laboratory-scale self-heating gasification process. The generated gasification product gas (CO, H2, CH4, etc.) is discharged through the gas outlet at the upper end of the reaction tube 1. During the reaction of the raw material, the heat carrier 4 can supply heat to the reaction system and also absorb the heat generated by the reaction system. By measuring the temperature of the heat carrier 4 before and after the reaction, the amount of heat exchanged with the reaction system can be calculated.

[0029] The gasification agent referred to in the above examples includes two types, the first type being any gas containing oxygen (pure oxygen, air, etc.), and the second type being specifically steam, CO2, or a mixture of the two in any proportion. The raw material to be treated generally refers to various solid fuels (such as coal, biomass, etc.) and combustible solid waste (such as RDF, organic sludge, etc.), but also includes other gaseous or liquid fuels or waste that can be co-gasified with these solid fuels (such as waste oil, organic waste gas, etc.).

[0030] Example 2

[0031] Reference Figure 2The embodiment is basically the same as the scheme of the embodiment 1, the only difference is that the reaction tube 1 in the embodiment is a down-draft fixed bed reaction tube, the reaction bed in the reaction tube 1 is a fixed bed, the first communication pipe is used as the raw material inlet to put the solid fuel into the reaction tube 1, the third communication pipe is used as the gas outlet to discharge the generated gas, and the second communication pipe is used as the gasification agent inlet to put the gasification agent into the reaction tube 1.

[0032] Embodiment 3

[0033] Reference Figure 3 The embodiment is basically the same as the scheme of the embodiment 1, the only difference is that the reaction tube 1 in the embodiment is a fluidized bed reaction tube, the reaction bed in the reaction tube 1 is a fluidized bed, the first communication pipe is used as the raw material inlet to put the solid fuel into the reaction tube 1, the second communication pipe is used as the gas outlet to discharge the generated gas, and the third communication pipe is used as the gasification agent inlet to put the gasification agent into the reaction tube 1.

[0034] The above is only the preferred embodiment of the present application, and does not limit the technical scope of the present application, so any slight modification, equivalent change and modification made according to the technical essence of the present application to the above embodiment are still within the scope of the technical scheme of the present application.

Claims

1. A small-scale self-heating reaction device, characterized in that, The device includes an insulated container, within which a heat carrier container is housed. The top of the heat carrier container is sealed and welded to the top of the insulated container via a first sealing sleeve, and the bottom of the heat carrier container is sealed and welded to the bottom of the insulated container via a second sealing sleeve. A vacuum jacket exists between the heat carrier container and the insulated container. A vertical through-hole is provided in the center of the heat carrier container, and a reaction tube passes through the vertical through-hole. A reaction bed is provided inside the reaction tube, and the top of the reaction tube is connected to a first connecting pipe and a second connecting pipe. The second connecting pipe extends through the top wall of the heat preservation tank and out of the heat preservation tank. The bottom end of the reaction tube extends downward through the bottom wall of the heat preservation tank and is connected to the third connecting pipe. A heating rod and a first temperature measuring tube are vertically arranged inside the heat carrier tank. A first temperature measuring element is arranged near the top of the heat carrier tank inside the first temperature measuring tube. A second temperature measuring element is arranged near the bottom of the heat carrier tank inside the first temperature measuring tube. An upper heating ring is arranged on the inner top wall of the heat preservation tank. A lower heating ring is arranged on the inner bottom wall of the heat preservation tank. The bottom of the reaction tube, located outside the insulated tank, is fitted with an insulation layer.

2. The small self-heating reaction device according to claim 1, characterized in that, The insulated tank is formed by sealing and welding an upper insulated plate, a lower insulated plate, and a side insulated plate. The upper heating ring is fixedly connected to the lower surface of the upper insulated plate, and the lower heating ring is fixedly connected to the upper surface of the lower insulated plate.

3. The small self-heating reaction device according to claim 1, characterized in that, The bottom of the heat preservation tank is provided with an air extraction pipe that communicates with the vacuum jacket. The end of the air extraction pipe away from the heat preservation tank is connected in sequence to a pressure gauge, a valve and a vacuum pump.

4. A small self-heating reaction device according to claim 1, characterized in that, The reaction tube is equipped with a vertical second temperature measuring tube, and several third temperature measuring elements are arranged sequentially from top to bottom inside the second temperature measuring tube.

5. A small self-heating reaction device according to claim 1, characterized in that, The heat transfer medium is one of quartz sand, silicon carbide, or ceramic balls.

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