CN114755136A - Thermogravimetric analysis device and system for gas-solid reaction kinetics research - Google Patents
Thermogravimetric analysis device and system for gas-solid reaction kinetics research Download PDFInfo
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Abstract
本发明涉及一种用于气固反应动力学研究的热重分析装置及系统，属于气固反应动力学研究设备技术领域，解决了现有设备无法为细粒度氢氧化钙/氧化钙材料体系气固反应试验提供接近恒温条件的问题，包括电阻炉，电阻炉与升降机构连接，电阻炉的内部设置有反应器，反应器顶端封闭，底端敞口设置，反应器内部固定有供气盘管，供气盘管一端从反应器顶部伸出至反应器外部，作为进气端，另一端作为出气端连接有吹扫管，反应器正下方设置有样品放置机构，样品放置机构安装于称重机构，采用本发明的热重分析装置，能够获取细粒度的氢氧化钙/氧化钙材料体系在流态化条件下的反应动力学信息。
The invention relates to a thermogravimetric analysis device and system for gas-solid reaction kinetics research, belongs to the technical field of gas-solid reaction kinetics research equipment, and solves the problem that the existing equipment cannot be used for fine-grained calcium hydroxide/calcium oxide material system gas The solid reaction test provides problems close to constant temperature conditions, including the resistance furnace, the resistance furnace is connected with the lifting mechanism, the reactor is set inside the resistance furnace, the top of the reactor is closed, the bottom end is open, and the gas supply coil is fixed inside the reactor , one end of the gas supply coil extends from the top of the reactor to the outside of the reactor, as the inlet end, and the other end as the outlet end is connected with a purging pipe. The mechanism, using the thermogravimetric analysis device of the present invention, can obtain the reaction kinetic information of the fine-grained calcium hydroxide/calcium oxide material system under fluidized conditions.
Description
Technical Field
The invention relates to the technical field of gas-solid reaction kinetics research equipment, in particular to a thermogravimetric analysis device and a system for gas-solid reaction kinetics research.
Background
The statements herein merely provide background information related to the present disclosure and may not necessarily constitute prior art.
The heat energy storage is a key technology for solving the problems of intermittency and fluctuation of solar heat energy and realizing the recovery and reutilization of industrial waste heat. The thermal energy storage mainly comprises sensible heat storage, latent heat storage and thermochemical heat storage. Thermochemical heat storage uses the heat of reaction of a reversible chemical reaction to achieve the storage and release of heat. Compared with sensible heat and latent heat storage, thermochemical heat storage has the advantages of high energy storage density and long energy storage period, so thermochemical heat storage is a technology with wide application prospect.
The thermochemical heat storage system based on calcium hydroxide decomposition and calcium oxide hydration has the advantages of low material cost, high energy storage density, good reaction reversibility and circulation stability, rapid reaction kinetics and no toxicity of materials, so the thermochemical heat storage system is widely considered as a thermochemical heat storage material system with industrial application prospect. With the development of large-scale high-efficiency heat storage technology, in order to provide an acceptable heat storage and release power, the heat storage material is required to have excellent heat transfer and mass transfer characteristics in the reactor, so that the thermochemical heat storage using the fluidized bed reactor becomes a hot topic at present. The fluidized thermochemical heat storage process based on a calcium hydroxide/calcium oxide material system is a dynamic process coupling material reaction kinetics and heat and mass transfer, so that the reaction kinetics of the heat storage material under the fluidizing condition are very important, and the selection of key design parameters of the circulating fluidized bed reactor is influenced.
The fluidized bed reactor has excellent heat transfer and mass transfer characteristics, and the reaction process of the granular materials in the fluidized bed reactor is basically constant temperature reaction. In order to obtain the reaction kinetics of the calcium hydroxide/calcium oxide material system under the fluidization condition, an apparatus capable of providing excellent heat transfer and mass transfer characteristics for the material system is required to carry out the reaction kinetics research. At present, the mainstream gas-solid reaction kinetic research equipment is a thermogravimetric analyzer and a micro fluidized bed analyzer. The thermogravimetric analyzer obtains the change of the sample mass by adopting a temperature programming method (the maximum temperature rise rate is generally less than 50 ℃/min), can accurately monitor the mass change of the sample in the reaction process and accurately control the temperature rise rate of a heater, and has already realized wide commercial application at present. However, the inventors found that the thermogravimetric analyzer cannot study the reaction characteristics of the unstable substance under isothermal conditions, for example, it cannot study the decomposition reaction of calcium hydroxide under any set temperature range close to the constant temperature, because the decomposition rate of calcium hydroxide at higher temperature is very fast, so the calcium hydroxide in the thermogravimetric analyzer basically completes the decomposition reaction before reaching the expected temperature, and thus the thermogravimetric analyzer cannot study the isothermal decomposition reaction of calcium hydroxide. Meanwhile, the thermogravimetric analyzer is also limited by the design principle and structure, and the adopted purge gas amount is low (the maximum purge gas amount is generally less than 100mL/min), so that the inhibition effect of gas diffusion in the reactor on the reaction is difficult to eliminate, the mass transfer inhibition phenomenon of the sample in the thermogravimetric analyzer is obvious, and the thermogravimetric analyzer cannot provide excellent mass transfer conditions for the sample. It is for the above reasons that the thermogravimetric analyzers generally use small amounts of sample (about 5mg), but when the composition of the material is complex (e.g. carbide slag, a multi-component mixed substance with calcium hydroxide as the main component), such small amounts of sample are difficult to represent the overall properties of the material. The analysis shows that the thermogravimetric analyzer cannot provide high-efficiency heat transfer and mass transfer conditions for the sample, so that the thermogravimetric analyzer cannot provide reliable reaction kinetic information for fluidized thermochemical heat storage research of a calcium hydroxide/calcium oxide material system.
The micro fluidized bed analyzer provides excellent heat and mass transfer conditions for a sample through the violent relative motion between inert bed material particles (generally quartz sand) and sample particles, and can provide a rapid temperature rise rate to realize isothermal reaction, so that the micro fluidized bed analyzer is widely applied to the fluidization field. The micro-fluidized bed analyzer relies on the gas concentration signal at the reactor outlet as a raw signal to reverse the reaction kinetics of the material. Since gas back-mixing and axial diffusion of components occur in the fluidized bed reactor, and a concentration gradient also occurs in the sampling line from the outlet of the fluidized bed reactor to the inlet of the gas analyzer, this will also lead to axial diffusion of gas components, and the turbulent structure will also lead to gas back-mixing. The above factors cause the gas flow to deviate from the plug flow, so that the gas concentration signal obtained by the gas analyzer has a certain degree of distortion, and accurate reaction kinetic information cannot be obtained. For the calcium hydroxide gas-solid reaction with extremely fast reaction rate, the distortion of the gas signal will be more serious. Gas signals in the heat storage process of calcium hydroxide and the heat release process of calcium oxide are water vapor, and both mass spectrometers and Fourier transform infrared absorption spectrometers have difficulty in real-time quantitative and accurate detection of water vapor (for example, calibration equipment needs water vapor standard gases with different concentrations, and no commercial water vapor standard gas exists at present), so that the micro fluidized bed analyzer cannot be used for dynamic research of fluidization thermochemical heat storage reaction of a calcium hydroxide/calcium oxide material system.
The prior art also proposes the concept of fluidized bed thermogravimetry, which places the entire fluidized bed reactor on a real-time on-line weighing device, feeds material from the upper end of the fluidized bed reactor, and then monitors the mass change of the material under the fluidization condition. Compared with a micro fluidized bed analyzer, the fluidized bed thermogravimetry uses a real-time mass signal as an original signal for reaction kinetic calculation, so that the material reaction kinetic characteristics can be directly researched according to the mass signal. However, the thermogravimetry of the fluidized bed has strict requirements on the particle size of the material, and the particle size of the material needs to be more than 150 μm. Fluidized bed thermogravimetry cannot study powder materials because powder materials are directly blown out by fluidizing air directed toward the powder materials from below the powder materials after being fed from the upper part of the fluidized bed, and mass information cannot be obtained. Neither calcium hydroxide (analytically pure calcium hydroxide with a particle size range of 0-100 μm and a median particle size of about 4 μm) nor calcium hydroxide-based carbide slag (particles of 100 μm or less accounting for about 80% and a median particle size of about 30 μm) can be reliably studied by fluidized bed thermogravimetry. The thermal mass of the fluidized bed also has a pseudo mass (i.e., the gas lines and temperature and pressure measurement point lines connected to the fluidized bed reactor may have a fluctuating effect on the overall mass of the fluidized bed), which also adversely affects the measured mass signal.
In summary, there is currently a lack of equipment that can study the reaction kinetics of calcium hydroxide/calcium oxide material systems under fluidization conditions.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, provides a thermogravimetric analysis device for gas-solid reaction kinetics research, and can obtain reaction kinetics information of a fine-grained calcium hydroxide/calcium oxide material system under a fluidization condition.
In order to achieve the purpose, the invention adopts the following technical scheme
In a first aspect, an embodiment of the present invention provides a thermogravimetric analysis device for gas-solid reaction kinetics research, which includes a resistance furnace, the resistance furnace is connected to a lifting mechanism, a reactor is disposed inside the resistance furnace, a top end of the reactor is closed, a bottom end of the reactor is open, a gas supply coil is fixed inside the reactor, one end of the gas supply coil extends out of the reactor from a top of the reactor to an outside of the reactor and serves as a gas inlet end, the other end of the gas supply coil serves as a gas outlet end and is connected to a purging tube, a sample placement mechanism is disposed under the reactor, and the sample placement mechanism is mounted on a weighing mechanism.
Optionally, a first thermocouple is inserted into the reactor, and the first thermocouple is connected with the resistance furnace temperature control instrument.
Optionally, the sample placing mechanism comprises a crucible, the crucible is placed on a tray, the tray is fixed to the top end of the connecting rod, and the bottom end of the connecting rod is connected with the weighing mechanism.
Optionally, the crucible comprises a sample placing part, the edge of the sample placing part is provided with a flange part, and correspondingly, the purging pipe is horizontally arranged so that the gas blown by the purging pipe does not blow the sample out of the crucible.
Optionally, the crucible is made of a platinum material, the tray and the connecting rod are made of a quartz material, and a heat insulation pad is arranged between the crucible and the tray.
Optionally, the connecting rod is a hollow rod, a second thermocouple is arranged inside the hollow rod and connected with the monitoring terminal through a temperature transmitter, a probe at one end of the second thermocouple extends into a groove formed in the bottom of the crucible, and the second thermocouple is arranged in a non-contact manner with the cavity surface of the cavity in the hollow rod.
Optionally, the periphery of the sample placing mechanism is also provided with a cooling water tray, and the cooling water tray is connected with a water cooler.
Optionally, the lifting mechanism adopts a screw lifting mechanism.
In a second aspect, an embodiment of the present invention provides a thermogravimetric analysis system for a gas-solid reaction kinetics study, including the thermogravimetric analysis device for a gas-solid reaction kinetics study described in the first aspect, and an end of the gas supply coil extending out of the reactor is connected to a gas supply system.
Optionally, the air supply system includes the air mixing chamber, and the end of giving vent to anger of air mixing chamber passes through the pipeline and is connected with the inlet end of air feed coil pipe, and the inlet end of air mixing chamber is connected with air supply branch road and water vapor supply branch road, and the air supply branch road includes the air supply, and the air supply is connected with the inlet end of heater, and the air mixing chamber is connected to the end of giving vent to anger of heater, and the water vapor supply branch road includes the syringe pump, and the export and the vaporizer of syringe pump are connected, and the play steam end and the air mixing chamber of vaporizer are connected.
The invention has the beneficial effects that:
1. the thermogravimetric analysis device of the invention is characterized in that the resistance furnace is connected with the lifting mechanism, and the sample placing mechanism is positioned under the reactor with an opening at the bottom, so that the resistance furnace drives the reactor to descend through the lifting mechanism after the interior of the reactor reaches a set temperature, the sample placing mechanism can enter the reactor, and the sample can quickly reach the expected temperature, compared with the current thermogravimetric analyzer, the thermogravimetric analysis device avoids the decomposition reaction of calcium hydroxide which is caused by slow temperature rise before the calcium hydroxide reaches the expected temperature, realizes the decomposition reaction of the calcium hydroxide under the condition of any temperature range close to the constant temperature, and simultaneously has the air supply coil pipe and the purging pipe, and combines the quick lifting motion of the resistance furnace, so that the sample can quickly reach the expected temperature and reduce the mass transfer resistance in the reaction process, and provides excellent heat transfer and mass transfer conditions for the sample, while using reliable mass signals to conduct reaction kinetics studies.
2. According to the thermogravimetric analysis device, the crucible is adopted as the sample holding mechanism, the crucible is provided with the flange, and the purging pipe is horizontally arranged, so that gas blown out by the purging pipe cannot directly act on a sample in the crucible, the sample cannot be blown away from the crucible, compared with the conventional fluidized bed thermogravimetric analysis, the thermogravimetric analysis device has no requirement on the particle size of the sample, is suitable for the thermogravimetric analysis of a calcium hydroxide/calcium oxide material system with fine particle size, and meanwhile compared with the conventional thermogravimetric analyzer, the thermogravimetric analysis device can provide larger purging gas amount, and can eliminate the inhibition effect of gas diffusion in a reactor on reaction.
3. According to the thermogravimetric analysis device, the weighing device is adopted to directly weigh the sample, and compared with a micro fluidized bed analyzer, the obtained reaction kinetic information is more accurate.
4. According to the thermogravimetric analysis device, the crucible is made of the platinum material, the heat insulation pad is arranged between the crucible and the tray, and the platinum is high-temperature resistant, low in specific heat capacity and good in heat conductivity, so that a sample can quickly reach an expected temperature.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application.
FIG. 1 is a schematic view of the overall structure of embodiment 1 of the present invention;
FIG. 2 is a graph showing the results of the decomposition reaction of the calcium hydroxide sample in example 2 of the present invention;
wherein, 1-gas source; 2-mass flow meter; 3-a heater; 4-a micro-injection pump; 5-a vaporizer; 6-air mixing chamber; 7-resistance furnace temperature control instrument; 8-a reactor; 9-a screw lifting mechanism; 10-resistance furnace; 11-an air supply coil; 12-a first thermocouple; 13-a crucible; 14-a quartz tray; 15-a hollow quartz rod; 16-a second thermocouple; 17-fixed damping; 18-a water chiller; 19-a cooling water pan; 20-electronic scale; 21-a clamping head; 22-a temperature transmitter; 23-computer.
Detailed Description
Example 1
The embodiment provides a thermogravimetric analysis device for gas-solid reaction kinetics research, as shown in fig. 1, the thermogravimetric analysis device comprises a resistance furnace 10, a reactor 8 is arranged in a cavity inside the resistance furnace 10, the resistance furnace 10 can heat the reactor 8, the internal temperature of the reactor 8 reaches a set temperature, and the reactor 8 provides a set environmental temperature for sample reaction.
In this embodiment, the length of the constant temperature zone of the furnace body of the resistance furnace 10 is 400mm, the maximum heating temperature of the resistance furnace 10 is 1100 ℃, and the resistance furnace 10 may be the conventional one, and will not be described in detail herein.
Be provided with sample placement mechanism under reactor 8 for place the sample, resistance furnace 10 is connected with elevating system 9 for resistance furnace 10 and reactor 8 can be elevating movement, and when reactor 8 downstream, because the uncovered setting in its bottom, therefore sample placement mechanism can get into inside the reactor.
The lifting mechanism 9 adopts a screw lifting mechanism, and the screw lifting mechanism in the embodiment can drive the resistance furnace to do lifting motion at the speed of 50 mm/s.
Specifically, lead screw elevating system 9 includes the lead screw of the vertical setting of axis, and the both ends and the support body of lead screw rotate to be connected, and one of them tip and the driving motor of lead screw are connected, and driving motor can drive the lead screw and rotate, and lead screw threaded connection has the lead screw slider, the shell fixed connection of lead screw slider and resistance furnace, the shell of resistance furnace still with the vertical guide rail sliding connection who sets up of axis, the guide rail is used for leading to the elevating movement of resistance furnace.
Adopt lead screw elevating system 9, conveniently control resistance furnace's lifting speed and lift position, satisfy experimental requirement, in some other embodiments, elevating system also can adopt rack and pinion formula elevating system or cut fork elevating system etc..
The top cap of reactor 8 is provided with a thermocouple socket and an air feed coil pipe access mouth, the top cap is fixed with first thermocouple 12 through the thermocouple socket, inside first thermocouple 12 set up the tip of probe and stretched into reactor 8, a temperature for detecting in the reactor, first thermocouple 12 is connected with resistance furnace temperature controller 7, first thermocouple 12 can send the temperature that obtains with detecting for resistance furnace temperature controller 7, resistance furnace temperature controller 7 works according to received temperature control resistance furnace 10, so that reach required temperature and remain stable in the reactor 8.
Be provided with air supply coil 11 in the reactor 8, air supply coil 11 in this embodiment adopts the spiral pipe, sets up in the periphery of first thermocouple 12, and air supply coil 11's one end stretches out to the reactor 8 outside through air supply coil access mouth to with the top cap fixed connection of reactor 8. The end part of the air supply coil pipe 11 extending out of the reactor 8 serves as an air inlet end, the other end of the air supply coil pipe serves as an air outlet end, a purging pipe is arranged, the air inlet end of the air supply coil pipe 11 can be externally connected with an air source, and the purging pipe can blow air out, so that high-speed purging is carried out on a set range space above a sample. The gas supply coil pipe in the embodiment is made of stainless steel, and is high-temperature resistant and long in service life.
A sample placing mechanism is arranged right below the reactor 8, the sample placing mechanism comprises a crucible 13, the crucible 13 is used for placing a sample, the crucible 13 in the embodiment is made of a platinum material, the sample placing mechanism comprises a placing part, the placing part is horizontally arranged and used for placing the sample, and a flange part is arranged at the edge of the placing part to prevent the sample from being separated from the placing part.
Correspondingly, the axis of the purging pipe is horizontally arranged, the gas blown out from the purging pipe can flow along the top surface of the flange part, the gas cannot directly act on a sample in the crucible, the sample is prevented from being blown away from the crucible by the blown gas, the arrangement mode is adopted, compared with the existing fluidized bed thermogravimetry, the requirement on the particle size of the sample is avoided, and the device is suitable for the thermogravimetric analysis of a calcium hydroxide/calcium oxide material system with fine particle size.
The crucible 13 is made of platinum materials, and the platinum materials are high temperature resistant, low in specific heat capacity and good in heat conductivity, so that the sample can reach the expected temperature quickly.
The crucible 13 is placed on a tray, the tray in this embodiment is a quartz tray 14, and in order to prevent heat of the crucible 13 from being transferred to the quartz tray 14, a heat insulation pad is arranged between the crucible 13 and the quartz tray 14, and the heat insulation pad is made of existing heat insulation materials, such as glass fiber and rock wool.
The quartz tray 14 is fixedly connected with the top end of the connecting rod, and the bottom end of the connecting rod is fixed on the weighing mechanism.
The connecting rod in this embodiment adopts hollow quartz rod 15, and inside has the cavity, and hollow quartz rod 15 is cylindrical pole or square pole, and the top of hollow quartz rod 15 and the bottom surface fixed connection of quartz tray, the bottom of hollow quartz rod 15 is fixed in the weighing mechanism through holding head 21.
The weighing mechanism adopts the existing electronic scale 20, a scale pan of the electronic scale 20 is provided with a clamping head matched with the hollow quartz rod 15, in one embodiment, the clamping head 21 can adopt a clamping block, the clamping block is provided with a slot matched with the hollow quartz rod, and the bottom end of the hollow quartz rod is inserted into the slot.
The electronic scale is connected with the monitoring terminal, the monitoring terminal adopts a computer, mass data of a sample in the crucible can be acquired in real time on line, the measuring range of the electronic scale in the embodiment is 220g, the readability is 0.1mg, and the mass data acquisition frequency is 1/s.
In order to avoid the influence of the high-temperature environment of the reactor on the electronic scale, a cooling water tray 19 is arranged on the periphery of the bottom end of the hollow quartz rod, specifically, a through hole with the diameter larger than the outer diameter of the hollow quartz rod is formed in the center of the cooling water tray, the hollow quartz rod penetrates through the cooling water tray through the through hole, the cooling water tray 19 is connected with a water cooler 18, the water cooler 18 can provide cooling circulating water (10L/min, 15 ℃), the hollow quartz rod 15 close to the electronic scale 20 and the environment around the hollow quartz rod are cooled, and the electronic scale is guaranteed not to be influenced by the high-temperature environment in the reactor.
In this embodiment, the mass of the sample is directly obtained by using the electronic scale 20, and the obtained reaction kinetic information is more accurate than that of a micro fluidized bed analyzer.
The second thermocouple 16 is arranged in the cavity inside the hollow quartz rod 15, the end part of the probe of the second thermocouple 16 penetrates through the quartz tray 14 and the heat insulation pad through the hole arranged on the quartz tray 14 and then extends into the groove arranged on the bottom surface of the crucible 13, the second thermocouple 16 is not contacted with the groove surface of the groove, the thickness of the part of the groove arranged at the bottom of the crucible 13 is only 1mm, and by adopting the arrangement mode, compared with a traditional thermogravimetric analyzer, the temperature of a sample can be measured more accurately, and the change of the temperature of the sample can be measured through the second thermocouple 16.
The other end of the second thermocouple 16 extends out of the hollow quartz rod 15 through a hole formed in the rod wall of the hollow quartz rod 15 and is fixedly connected with a fixed damper 17, and the fixed damper 17 is fixed on a cooling water disk 19.
Through the setting of the fixed damping 17, the second thermocouple 16 can be kept fixed, so that the second thermocouple 16 is not in contact with the cavity surface of the hollow quartz rod 15 cavity, and the problem of inaccurate quality signal caused by contact friction is avoided.
Specifically, the fixed damper 17 is provided with a fixed hole, the second thermocouple 16 is inserted into the fixed hole and is fixed with the fixed damper 17, the end of the second thermocouple 16 inserted into the fixed hole extends out of the fixed damper 17 and is connected with the temperature transmitter 22 through a signal line, the temperature transmitter 22 is connected with the monitoring terminal through a signal line, and the monitoring terminal adopts the computer 23.
Through the setting of fixed damping 17, avoided second thermocouple 16 and hollow quartz rod 15 contact on the one hand, on the other hand, when receiving external influence signal line to produce and rock, through fixed damping 17, second thermocouple 16 can not rock, has avoided influencing second thermocouple 16's normal work.
The second thermocouple 16 is connected with a computer 23 through a temperature transmitter 22, and records the temperature data of the sample in the crucible 13 in real time, wherein the acquisition frequency of the temperature data is 1/s.
When the thermogravimetric analysis device works, firstly, the resistance furnace 10 is lifted to the topmost end, the heat insulation pad is placed on the quartz tray 14, the crucible 13 is placed on the heat insulation pad, the electronic scale 20 carries out peeling and weighing operations, the resistance furnace 10 is started, the temperature in the reactor 8 is heated to the reaction temperature required by the experiment, and whether compressed air or mixed gas of compressed air and water vapor is introduced into the reactor through the air supply coil is determined according to the experimental study on heat storage reaction kinetics experiment or heat release reaction kinetics experiment. After the readings of the first thermocouple 12 reach the temperature required by the experiment and are stable, the water chiller 18 is started, a set amount of sample is weighed by using an analytical balance (readability 0.1mg) in the laboratory and is tiled in the crucible 13, the sample in the embodiment is a sample of a calcium hydroxide or calcium oxide material system, the computer 23 starts to acquire mass data of the electronic scale 20 and data of the second thermocouple 16, the lead screw lifting mechanism 9 is controlled to work, the resistance furnace 10 is lowered to a set position at a speed of 50mm/s, the set position is that the distance between the bottom end of the first thermocouple 12 and the upper surface of the crucible 13 is 5mm, the axis of the purging tube is flush with the bottom end of the first thermocouple, namely the distance between the axis of the purging tube and the upper surface of the crucible is 5mm, and the temperature of the position of the crucible 13 can be ensured to meet the research requirements at this time. After the resistance furnace 10 is lowered to the set position, the sample starts to react, when the mass weighed by the electronic scale 20 is not changed any more, the reaction is considered to be completed, and after the sample experiment is completed, a group of blank experiments without the sample need to be performed under the same experiment conditions. And subtracting the mass data of the blank experiment from the mass data of the sample experiment to obtain the thermogravimetric curve of the sample. The accuracy of the mass signal obtained by the rapid response thermogravimetric analysis system was confirmed by comparing the mass of the sample obtained from the laboratory analytical balance prior to the experiment with the mass of the sample prior to the reaction in the system.
After the resistance furnace 10 enables the interior of the reactor 8 to reach the set temperature, the reactor 8 is driven to descend through the lifting mechanism, the sample placing mechanism can enter the reactor 8, the sample can quickly reach the expected temperature, compared with the existing thermogravimetric analyzer, the decomposition reaction of calcium hydroxide which is caused by slow temperature rise is avoided before the calcium hydroxide does not reach the expected temperature, the decomposition reaction of the calcium hydroxide under the condition that the calcium hydroxide is close to the set temperature range with constant temperature at any fixed point is realized, meanwhile, the thermogravimetric analysis device of the embodiment is provided with the air supply coil pipe 11 and the purging pipe, the mass transfer resistance in the reaction process can be quickly reached by combining with the quick lifting movement of the resistance furnace 10, the excellent heat transfer and mass transfer conditions are provided for the sample, and meanwhile, the reaction dynamics research is carried out by utilizing reliable mass signals.
Example 2
The embodiment provides a thermogravimetric analysis system for gas-solid reaction kinetics research, which, as shown in fig. 1, includes the thermogravimetric analysis device for gas-solid reaction kinetics research described in embodiment 1.
The air inlet end of the air supply coil 11 is connected to an air supply system, and the air supply system is used for supplying air with a set pressure or mixed gas of the air and water vapor to the air supply coil 11.
Air supply system includes air mixing chamber 6, the end of giving vent to anger of air mixing chamber 6 is connected with the inlet end of air feed coil pipe 11 through the pipeline, air mixing chamber 6 has two inlet ends, air feed branch road is connected to one of them inlet end, another inlet end is connected steam and is supplied with the branch road, air feed branch road is including the air supply 1 that loops through the tube coupling, mass flow meter 2 and heater 3, the end of giving vent to anger of heater 3 is through the inlet end of tube coupling air mixing chamber 6, air supply 1 adopts the gas cylinder, can be to the air of injecting set pressure in the air mixing chamber 6, heater 3 is used for heating the air.
In this embodiment, the gas source 1 can provide 0.15MPa of gas, the gas flow is adjusted to 500mL/min by the mass flow meter 2, and the heater is set to 180 ℃ for preheating the gas.
In order to meet the research requirements of the calcium oxide hydration reaction, a water vapor supply branch is arranged, the water vapor supply branch comprises an injection pump and a vaporizer 5 which are sequentially connected through a pipeline, and the vapor outlet end of the vaporizer 5 is connected with the other gas inlet end of the gas mixing chamber 6 through a pipeline.
The injection pump is a micro-injection pump 4, the micro-injection pump 4 injects liquid water (0.184nL/min-83.318mL/min) into the vaporizer 5, and the vaporizer 5 generates continuous and stable water vapor with the temperature of 280 ℃. The gas from the heater 3 is fully mixed with a certain amount of water vapor in the gas mixing chamber 6, and mixed gas with a certain water vapor partial pressure can be formed.
The gas from the gas mixing chamber 6 enters the gas supply coil 11 in the reactor 8, the gas sweeps the surface of a sample in the crucible 13 after sufficient heat exchange in the gas supply coil 11, the gas supply coil 11 adopts a spiral pipe, the heat exchange area is increased, and the temperature when the gas reaches the surface of the crucible 13 is ensured to be consistent with the set temperature in the reactor 8. The connecting pipeline between the vaporizer 5 and the gas mixing chamber 6, the connecting pipeline between the heater 3 and the gas mixing chamber 6, the connecting pipeline outside the gas mixing chamber 6 and between the gas mixing chamber 6 and the gas supply coil 11 in the reactor 8 are all sleeved with heat tracing bands (the heat tracing temperature is 180 ℃).
The operation of the system of the present invention will be described by taking the decomposition heat storage reaction of pure calcium hydroxide as an example.
The screw lifting mechanism 9 drives the initial position of the reactor 8 to the top of the guide rail. An insulation pad is placed on the quartz tray 14, the crucible 13 is placed on the insulation pad, and the electronic scale 20 performs a peeling and weighing operation. The resistance furnace 10 was started to heat the temperature inside the reactor 8 to the reaction temperature required for the experiment. Gas (air, 500mL/min) was introduced into the air supply branch. And judging whether the temperature in the reactor 8 is stable or not through the first thermocouple 12, and starting the water cooler 18 after the reading of the first thermocouple 12 meets the requirement and is stable. An appropriate amount of an analytically pure calcium hydroxide sample was weighed using an analytical balance (readability 0.1mg) in the laboratory and laid flat in crucible 13. In this example, the sample mass of calcium hydroxide was 70.5mg, and the computer started to collect the mass data of the electronic scale 20 and the temperature data of the second thermocouple 16. The screw elevating mechanism 9 is controlled to work, the resistance furnace 10 is descended to the designated position at the speed of 50mm/s, and the reaction of the sample is started. The reaction is considered complete when the mass signal no longer changes. After completion of the sample experiment, a set of blank experiments without sample was performed under the same experimental conditions. As shown in fig. 2, the thermogravimetric curve of the sample can be obtained by subtracting the mass data of the blank experiment from the mass data of the sample experiment, and the reaction kinetic parameters for analyzing the decomposition of pure calcium hydroxide can be calculated by using the collected mass data. This will provide more reliable reaction kinetics information for fluidized thermochemical heat storage studies of calcium hydroxide.
By adopting the analysis system of the embodiment, a reliable research means can be provided for the research on the reaction kinetics of the fluidized thermochemical heat storage of calcium hydroxide/calcium oxide, and it can be understood that the analysis system of the embodiment can also be applied to the research on the reaction kinetics of the fluidized thermochemical heat storage of carbide slag taking calcium hydroxide as a main component and the research on the reaction kinetics of the fluidized thermochemical heat storage of magnesium hydroxide/magnesium oxide.
Although the embodiments of the present invention have been described with reference to the accompanying drawings, it is not intended to limit the scope of the present invention, and it should be understood by those skilled in the art that various modifications and variations can be made without inventive efforts by those skilled in the art based on the technical solution of the present invention.
Claims (10)
1. A thermogravimetric analysis device for gas-solid reaction kinetics research, a serial communication port, including the resistance furnace, the resistance furnace is connected with elevating system, the inside of resistance furnace is provided with the reactor, the reactor top is sealed, the uncovered setting in bottom, reactor inside is fixed with the air feed coil pipe, air feed coil pipe one end stretches out to the reactor outside from the reactor top, as the inlet end, the other end is connected with as the end of giving vent to anger and sweeps the pipe, be provided with sample placement mechanism under the reactor, sample placement mechanism installs in weighing machine and construct.
2. The thermogravimetric analysis device for the study on the kinetics of gas-solid reaction according to claim 1, wherein a first thermocouple is inserted into the reactor and connected with a resistance furnace temperature control instrument.
3. The thermogravimetric analysis device for a study of the kinetics of a gas-solid reaction as claimed in claim 1, wherein said sample placement mechanism comprises a crucible, said crucible is placed on a tray, said tray is fixed to the top end of a connecting rod, and the bottom end of said connecting rod is connected to the weighing mechanism.
4. The thermogravimetric analysis device for the study of the kinetics of gas-solid reactions as claimed in claim 3, wherein the crucible comprises a sample placement portion, the edge of which is provided with a flange portion, and correspondingly, the purge tube is horizontally disposed so that the sample is not blown out of the crucible by the gas blown out of the purge tube.
5. The thermogravimetric analysis device for the study of the kinetics of a gas-solid reaction as claimed in claim 3, wherein the crucible is made of platinum, the tray and the connecting rod are made of quartz, and a thermal insulation pad is arranged between the crucible and the tray.
6. The thermogravimetric analysis device for the study on the kinetics of gas-solid reaction as claimed in claim 3, wherein the connecting rod is a hollow rod, a second thermocouple is arranged inside the hollow rod, the second thermocouple is connected with the monitoring terminal through a temperature transmitter, a probe at one end of the second thermocouple extends into a groove formed in the bottom of the crucible, and the second thermocouple is arranged in a non-contact manner with the cavity surface of the cavity inside the hollow rod.
7. The thermogravimetric analysis device for the study on the kinetics of gas-solid reaction according to claim 1, wherein a cooling water tray is further arranged on the periphery of the sample placement mechanism, and the cooling water tray is connected with a water cooler.
8. The thermogravimetric analysis device for the study of the kinetics of gas-solid reaction according to claim 1, wherein the lifting mechanism is a screw lifting mechanism.
9. The thermogravimetric analysis system for gas-solid reaction kinetics research is characterized by comprising the thermogravimetric analysis device for gas-solid reaction kinetics research as claimed in any one of claims 1 to 8, wherein the end part of the gas supply coil extending out of the reactor is connected with the gas supply system.
10. The thermogravimetric analysis system for the study on the kinetics of gas-solid reaction of claim 9, wherein the gas supply system comprises a gas mixing chamber, the gas outlet end of the gas mixing chamber is connected with the gas inlet end of the gas supply coil pipe through a pipeline, the gas inlet end of the gas mixing chamber is connected with a gas supply branch and a water vapor supply branch, the gas supply branch comprises a gas source, the gas source is connected with the gas inlet end of the heater, the gas outlet end of the heater is connected with the gas mixing chamber, the water vapor supply branch comprises an injection pump, the outlet of the injection pump is connected with the vaporizer, and the gas outlet end of the vaporizer is connected with the gas mixing chamber.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116106163A (en) * | 2023-03-08 | 2023-05-12 | 清华大学 | Thermogravimetric and gas analysis systems and test methods |
| CN119936081A (en) * | 2025-04-08 | 2025-05-06 | 西湖大学 | Experimental system for in-situ CT-thermogravimetric analysis simultaneous experiments |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20110018511A (en) * | 2009-08-18 | 2011-02-24 | 한국전력공사 | Thermogravimetric Analyzer and its Analysis Method |
| CN103760054A (en) * | 2014-01-16 | 2014-04-30 | 华中科技大学 | Thermal gravimetrical reactor applied to bulk specimen testing |
| CN104502535A (en) * | 2014-12-18 | 2015-04-08 | 东南大学 | Micro device and modeling method for studying gas-solid intrinsic chemical reaction kinetics |
| CN106053280A (en) * | 2016-06-12 | 2016-10-26 | 东南大学 | Micro fixed-bed reactor capable of realizing online thermal-state weighing and method |
| CN109030272A (en) * | 2018-07-26 | 2018-12-18 | 清华大学 | A kind of fluid bed heat weight analysis system for gas-solid reaction kinetic real―time precision measurment |
| CN113945606A (en) * | 2020-07-17 | 2022-01-18 | 中国科学院过程工程研究所 | A thermogravimetric analysis device and use thereof |
-
2022
- 2022-04-18 CN CN202210403748.0A patent/CN114755136B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20110018511A (en) * | 2009-08-18 | 2011-02-24 | 한국전력공사 | Thermogravimetric Analyzer and its Analysis Method |
| CN103760054A (en) * | 2014-01-16 | 2014-04-30 | 华中科技大学 | Thermal gravimetrical reactor applied to bulk specimen testing |
| CN104502535A (en) * | 2014-12-18 | 2015-04-08 | 东南大学 | Micro device and modeling method for studying gas-solid intrinsic chemical reaction kinetics |
| CN106053280A (en) * | 2016-06-12 | 2016-10-26 | 东南大学 | Micro fixed-bed reactor capable of realizing online thermal-state weighing and method |
| CN109030272A (en) * | 2018-07-26 | 2018-12-18 | 清华大学 | A kind of fluid bed heat weight analysis system for gas-solid reaction kinetic real―time precision measurment |
| CN113945606A (en) * | 2020-07-17 | 2022-01-18 | 中国科学院过程工程研究所 | A thermogravimetric analysis device and use thereof |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116106163A (en) * | 2023-03-08 | 2023-05-12 | 清华大学 | Thermogravimetric and gas analysis systems and test methods |
| CN119936081A (en) * | 2025-04-08 | 2025-05-06 | 西湖大学 | Experimental system for in-situ CT-thermogravimetric analysis simultaneous experiments |
| CN119936081B (en) * | 2025-04-08 | 2025-06-20 | 西湖大学 | Experimental system for in-situ CT-thermogravimetric analysis synchronous experiment |
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