Fused salt heat transfer, heat storage and heat exchange integrated green alcohol synthesis device

Abstract

The invention relates to a fused salt heat transfer, heat storage and heat exchange integrated green alcohol synthesis device. Fused salt with a wide temperature range, high specific heat capacity and normal pressure is adopted as a heat transfer medium, reaction heat generated by an inner cavity is continuously moved to an outer cavity to heat raw material gas by arranging a heat storage medium circulating system, and heat generated by the inner cavity is stored in the fused salt medium in a sensible heat form; the green alcohol synthesis device integrates the functions of heat transfer, heat storage and heat exchange, and can effectively solve the problems that the temperature of feed gas entering the synthesis device is low, the number of matched equipment is large, and the occupied space is large in the existing methanol synthesis technology; fused salt with high specific heat capacity is adopted to fully absorb high heat generated in the synthesis device, stable operation of main reaction in the synthesis device is maintained, the phenomena of maintaining the temperature in the synthesis device, converting carbon monoxide into carbon dioxide and removing the carbon dioxide in the prior art are avoided, the problem of carbon dioxide emission is avoided, the loss of feed gas is reduced, and the synthesis efficiency is improved. Therefore, the methanol yield is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of green methanol synthesis, and specifically relates to a molten salt heat transfer, heat storage and heat exchange integrated green alcohol synthesis device. Background Art

[0002] Methanol is the simplest saturated monohydric alcohol, an important chemical raw material and clean fuel, which can be used in organic chemical raw materials, new energy, medicine and other industries. Methanol can be obtained in three ways: chloroform hydrolysis, methane oxidation and raw gas method. The first two methods have limitations in the production of methanol and are not widely implemented in industry. At present, the raw gas method is often used in industry to produce methanol. The main components of raw gas are carbon monoxide, hydrogen and carbon dioxide. Due to the development and application of methanol fuel, the demand for methanol at home and abroad is increasing. The production of methanol through raw gas provides a new way to capture and consume carbon dioxide. The technology of producing methanol by raw gas method has gradually begun to receive attention.

[0003] The technology of synthesizing methanol from raw gas mainly has the following shortcomings: (1) The existing raw gas needs to be heated by a separate heater or preheated by a heat exchanger before entering the synthesis unit. The temperature of the preheated raw gas entering the synthesis unit is lower than the temperature of the catalyst bed inside the synthesis unit. The lower raw gas temperature leads to an increase in side reactions inside the synthesis unit. In addition, this method of heating the raw gas has certain requirements for land occupation and high investment costs. (2) Under the specific production conditions of green alcohol, the fixed tube sheet heat exchanger bundle built into the synthesis unit has a high-temperature heat alternating load of reaction exothermic heat, which can cause the synthesis unit to produce a large amount of methanol. It is easy to cause the heat exchange tube to detach from the fixed tube sheet and damage the heat exchange tube bundle. If the heat exchange tube bundle is damaged, the soft water in the heat exchange tube will leak into the synthesis device, causing catalyst failure and water instantaneous vaporization overpressure. (3) Under the specific reaction temperature conditions of green alcohol, the steam pressure corresponding to the saturated steam temperature in the drum is low, resulting in low steam quality, limited secondary use of recovered heat, and inability to generate superheated steam. The high energy and low use situation seriously does not comply with the energy utilization rules. (4) Since the process of synthesizing methanol from raw gas is an exothermic process, The existing methanol synthesis device uses high-pressure water cooling to control the reaction temperature inside the synthesis device by controlling the pressure of the external steam drum. This temperature control method requires the installation of a steam drum and a matching dosing device, which has certain limitations for users with small sites and high equipment investment costs; (5) The existing synthesis device uses water cooling to transfer heat, which requires a large amount of water resources for heat exchange. Since tap water will corrode the components inside the synthesis device, softened water or purified water needs to be used, and a separate water production device needs to be installed, resulting in increased water production costs and increased operating costs; (6) For the same molar oxygen The heat released by synthesizing methanol from carbon monoxide and carbon dioxide differs by nearly one-fold, with the former releasing much more heat than the latter. When the raw gas contains a high amount of carbon monoxide, the strong reaction heat generated rapidly inside the synthesis unit cannot be removed, resulting in overheating inside the synthesis unit and deactivation of the catalyst, which is not conducive to reaction operation control. To avoid this phenomenon, the existing treatment method converts carbon monoxide into carbon dioxide and hydrogen by adding water vapor, and then removes excess carbon dioxide. This treatment method reduces the amount of carbon elements participating in the reaction, resulting in a lower content of synthesized methanol and produces carbon dioxide emissions, and a separate conversion equipment needs to be set up.

[0004] In view of this, the present invention proposes a molten salt heat transfer, heat storage and heat exchange integrated green alcohol synthesis device. Summary of the invention

[0005] In view of the deficiencies of the prior art, the problem that the present invention intends to solve is to provide a molten salt heat transfer, heat storage, and heat exchange integrated green alcohol synthesis device. The synthesis device adopts molten salt with a wide temperature range, high specific heat capacity, and normal pressure as a heat transfer medium. By setting up a heat storage medium circulation system, the reaction heat generated in the inner cavity can be continuously moved to the outer cavity to heat the raw gas. The heat generated in the inner cavity is stored in the molten salt medium in the form of sensible heat, so that the green alcohol synthesis device can realize the integration of heat transfer, heat storage, and heat exchange functions. It can effectively solve the problems of low temperature of raw gas entering the synthesis device in the existing synthetic methanol technology, a large number of coordinating equipment, and a large space occupied; by using molten salt with high specific heat capacity to fully absorb the high heat generated inside the synthesis device, the stable operation of the main reaction inside the synthesis device is maintained, and the phenomenon of converting carbon monoxide into carbon dioxide and removing carbon dioxide in order to maintain the internal temperature of the synthesis device in the prior art is avoided, and the problem of carbon dioxide emission is avoided, and the loss of raw gas is reduced, thereby improving the methanol yield.

[0006] To achieve the above object, the present invention adopts the following technical solution:

[0007] A molten salt heat transfer, heat storage, and heat exchange integrated green alcohol synthesis device, comprising a reaction shell, and a heat exchange component, a cavity, and a raw gas distribution component arranged inside the reaction shell, characterized in that the reaction shell comprises a floating head, a reaction cylinder, and a lower head from top to bottom; the floating head is provided with a raw gas reaction outlet and a catalyst inlet; the lower head is provided with a catalyst discharge port and a heat storage medium outlet; the reaction cylinder is formed as a whole by an inner cylinder and an outer cylinder;

[0008] The cavity includes an inner cavity formed by the inner wall of the inner cylinder and the inner wall of the floating head, and an outer cavity formed by the outer wall of the inner cylinder, the inner wall of the outer cylinder and the inner wall of the lower head;

[0009] The heat exchange assembly includes a heat storage medium tube bundle in the inner cavity and a raw gas tube bundle in the outer cavity;

[0010] The raw gas distribution assembly is located at the bottom of the inner cavity surrounded by the inner cylinder;

[0011] A heat storage medium inlet is arranged on the inner cylinder, and the heat storage medium is located at the lower part of the connection position between the inner cylinder and the floating head, and at the upper part of the outer cylinder;

[0012] A raw gas inlet is arranged at the upper part of the outer cylinder;

[0013] The raw gas pipe bundle is located inside the outer cavity and is arranged from top to bottom in a spirally coiled form, the upper end of the coil is the start end, connected to the raw gas inlet, and the lower end is the end of the coil, connected to the raw gas distribution assembly in the inner cylinder; each ring of the raw gas pipe bundle is fixed to the inner wall of the outer cylinder and / or the outer wall of the inner cylinder through a support;

[0014] The heat storage medium tube bundle is located in the inner cavity of the inner cylinder, and is arranged in a spiral shape along the middle axis of the reaction shell from top to bottom. The upper end is the start end of the coil, which is connected to the heat storage medium inlet, and the lower end is the end of the coil, which passes through the inner cylinder and communicates with the outer cavity; each ring of the heat storage medium tube bundle is fixed to the inner wall of the inner cylinder through a support;

[0015] The heat storage medium outlet is connected to the circulation pump inlet through an external pipeline, and the circulation pump outlet is connected to the heat storage medium inlet through an external pipeline; the outer cavity and the heat storage medium tube bundle are filled with molten salt heat storage medium.

[0016] Furthermore, a flange is welded at the lower end of the floating head, and a counter-flange matching the flange at the lower end of the floating head is welded at the upper end of the inner cylinder. The floating head flange and the inner cylinder counter-flange are connected and fixed to the floating head and the inner cylinder by bolts, nuts and gaskets, which is a detachable connection; the outer cylinder is welded and fixed and covered on the outer layer of the inner cylinder, and the upper edge of the outer cylinder is 30-50cm away from the flange end face of the inner cylinder; the lower end of the outer cylinder is rigidly connected to the lower head by welding; the inner cylinder is in the form of a cylinder with a closed lower end and an open upper end.

[0017] Furthermore, the raw gas distribution assembly is composed of a raw gas elbow, a raw gas straight pipe and a raw gas distribution head welded together, and the raw gas elbow is connected to the lower coil end of the raw gas pipe bundle; preferably, the raw gas distribution head adopts a spherical mesh structure.

[0018] Furthermore, at the same height, the support members are evenly distributed along the circumferential direction, and the support members have a horizontal support surface, and the winding coil is fixed on the horizontal support surface by a semicircular clamp; the length of the support member in the outer cavity is the same as the width of the outer cavity or extends from the outer wall of the inner cylinder to the outer side of the pipe of the winding coil of the raw gas pipe bundle, and the length of the support member in the inner cavity is from the inner wall of the inner cylinder to the inner side of the pipe of the winding coil of the heat storage medium pipe bundle, and the support member can meet the function of supporting the raw gas pipe bundle / heat storage medium pipe bundle.

[0019] Furthermore, the straight pipe section of the catalyst unloading port passes through the lower head and the bottom end of the inner cylinder in sequence and is connected to the inner cavity, and the straight pipe section of the catalyst unloading port is connected to the contact point between the lower head and the bottom end of the inner cylinder by welding; the catalyst unloading port is sealed by a blind plate during the use of the synthesis device.

[0020] The catalyst is filled in the inner cavity formed by the inner wall of the inner cylinder and the inner wall of the floating head, and the filling coefficient reaches 80%.

[0021] Furthermore, the outer cavity is provided with oblique supports to provide support force for the inner cylinder, and the oblique supports are evenly arranged around the outer surface of the inner cylinder, and the specific number of oblique supports is set according to the total weight of the inner cylinder and the object carried inside the inner cylinder;

[0022] The oblique support includes a lower pad, an upper pad, and an oblique support rod. The lower pad is made into a pad with the same curvature as the inner surface of the lower head, and the lower pad is fully welded to the lower head. The upper pad is made into a pad with the same curvature as the outer surface of the inner cylinder, and the upper pad is fully welded to the inner cylinder. The two ends of the oblique support rod are respectively welded to the upper pad and the lower pad; preferably, the angle between the oblique support and the outer surface of the inner cylinder is between 30-45°.

[0023] Furthermore, the bottom of the inner cylinder is configured as a dome structure to facilitate catalyst unloading.

[0024] The heat storage medium is a binary salt or a ternary salt molten salt, and the selected molten salt should meet the properties of a wide temperature range, high specific heat capacity, good fluidity, low melting point and high boiling point.

[0025] Furthermore, the spacing between upper and lower adjacent pipes in the same type of raw gas pipe bundle and heat storage medium pipe bundle is 3-6 cm.

[0026] Furthermore, multiple thermocouples are arranged from top to bottom along the inner surface of the inner cylinder 6 for real-time monitoring of the internal temperature of the inner cylinder; the circulation pump 19 is a high-temperature resistant variable-frequency molten salt pump, which controls the frequency of the circulation pump 19 by receiving the temperature signal emitted by the multiple thermocouples, thereby controlling the flow velocity of the molten salt in the heat storage medium tube bundle 11 and adjusting the heat transfer rate.

[0027] Furthermore, the heat storage medium inlet is arranged on the side wall of the outer surface of the inner cylinder, between the upper end edge of the outer cylinder and the flange end surface of the inner cylinder, located at the upper right end of the reaction shell, and the heat storage medium inlet is welded to the wall surface of the inner cylinder.

[0028] Furthermore, the raw gas inlet is arranged on the side wall of the outer surface of the outer cylinder, located at the upper right end of the outer cylinder, directly below the heat storage medium inlet, and the raw gas inlet is welded to the wall of the outer cylinder.

[0029] Further, the heat storage medium outlet is located at the lower right side of the outer surface of the lower head, penetrates the lower head and is fixed to the contact part of the lower head by welding, and the heat storage medium outlet is located directly below the raw gas inlet and the heat storage medium inlet;

[0030] Furthermore, the catalyst feed inlet is located on the right side of the floating head at an angle of 45°, the catalyst feed inlet is connected to the contact position of the floating head by welding, and the catalyst feed inlet is blocked by a blind plate during use of the synthesis device.

[0031] Furthermore, the catalyst discharge port and the raw gas reaction outlet are installed on the middle shaft of the reaction shell.

[0032] Raw gas flows in the raw gas pipe bundle.

[0033] Furthermore, the heat storage medium tube bundle, the external cavity, the circulation pump, and the external pipeline together constitute a heat storage medium circulation system.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. The green alcohol synthesis device of the present invention is a device that couples heat transfer, heat storage, and heat exchange. Compared with the existing methanol synthesis device, the existing synthesis device needs to preheat or heat the raw gas through an external preheater or heater. Because the synthesis device of the present invention is provided with a preheating space composed of an outer cavity and a heat storage medium circulation system, the heat storage medium absorbs the reaction heat of the inner cavity to heat the raw gas in the outer cavity. The entire heating process occurs in an independent synthesis device, and there is no need to set up an external preheater and heater. The green alcohol synthesis device of the present invention has a simple structure, reduces the occupied space, and the cost of the entire methanol synthesis system is more economical, with a significant cost reduction of about 10%-20%.

[0036] 2. The heat transfer structure of the green alcohol synthesis device of the present invention is compared with the existing synthesis device. The existing synthesis device transfers heat through a built-in fixed tube sheet heat exchange tube bundle. The tube bundle adopts a fixed straight tube form, and high-pressure water is filled inside the straight tube for heat transfer. In this heat transfer method, the pipeline has a high pressure. The fixed straight tube form not only makes the pipeline poor in the ability to eliminate thermal stress, but also easily causes the pipeline to crack, causing the high-pressure water inside the tube bundle to leak, resulting in the deactivation of the catalyst of the synthesis device. The leaked high-pressure water instantly vaporizes and causes the synthesis device to overpressure, thereby causing a major safety accident. The heat transfer and heat storage pipe fittings of the present invention adopt a heat storage medium tube bundle, which uses a spiral winding form. The heat storage medium in the tube bundle is at normal pressure. The pressure on each pipeline in the tube bundle is small and the thermal stress can be effectively eliminated by rotating the curvature, avoiding the problem of easy cracking of the fixed tube sheet heat exchange tube bundle in the prior art, and enhancing the stability of the methanol synthesis device.

[0037] 3. The green alcohol synthesis device of the present invention adopts circulating molten salt filled inside the heat storage medium tube bundle to transfer heat from the inside of the synthesis device. No replenishment is required under special circumstances. Compared with the existing synthesis device that transfers heat by high-pressure water, a large amount of water resources need to be replenished to remove the reaction heat inside the synthesis device, which is restrictive for water-scarce areas. In order to avoid corrosion, the cooling water used by the equipment needs to use softened water or pure water, resulting in an increase in the operating cost of the existing technology for synthesizing methanol and an increase in equipment investment; the present invention is provided with a heat storage medium circulation system, and the heat storage medium is recycled in the synthesis device without replenishment. The present invention changes the traditional water phase change high-pressure heat transfer medium into a molten salt sensible heat and normal pressure heat transfer medium, and the vaporization temperature of the molten salt heat transfer medium is much higher than the maximum reaction temperature of the synthesis device, and there is no gasification phenomenon, which can effectively solve the internal leakage of the prior art and the water vaporization overpressure problem after the internal leakage; because the present invention adopts molten salt with high specific heat capacity as the heat storage medium, the dependence of the synthesis device on water resources can be eliminated, the water production equipment can be eliminated, and the investment cost, operating cost and construction period can be reduced.

[0038] 4. The green alcohol synthesis device of the present invention adopts a heat storage medium circulation system to achieve temperature control of the entire synthesis device, which is compared with the temperature control method of the existing methanol synthesis device. The existing technology mainly controls the final heat exchange temperature of the cooling water by controlling the pressure of the external steam drum, thereby controlling the reaction temperature inside the synthesis device; the present invention sets a normal pressure heat storage medium circulation system, and uses the heat storage medium to continuously transfer the heat of the inner cavity to the outer cavity. The heat of the heat storage medium in the outer cavity is used for heating the raw gas. The setting of the heat storage medium circulation system not only preheats the raw gas, but also meets the temperature control effect of the inner cavity. Compared with the existing technology, the temperature control method of the present invention adopts a normal pressure circulation form, which increases the safety of the system. The heat generated by the device itself is used to heat the raw gas. On the one hand, it reduces the input of external energy and can achieve self-production and self-consumption of heat; on the other hand, it eliminates equipment such as external steam drums and supporting dosing devices, reduces the space occupied by equipment, simplifies the synthetic methanol system, reduces investment costs, and shortens the construction period.

[0039] 5. Compared with the existing synthesis device, the green alcohol synthesis device of the present invention uses constant-pressure cooling water to transfer heat. When strong reaction heat is rapidly generated in the synthesis device, the heat absorbed by the cooling water under a given pressure is certain, and the existing synthesis device cannot quickly remove the heat generated inside. If the drum pressure is changed, the temperature of the saturated water will rise accordingly, resulting in the inability to control the temperature inside the synthesis device. The pressure bearing capacity of the pipeline is limited, and the ability of the existing synthesis device to cope with the temperature increase is weak; while the present invention adopts molten salt with high thermal conductivity, high specific heat capacity and high vaporization point, and utilizes the sensible heat of molten salt to transfer heat at normal pressure and store heat. The upper limit of the molten salt temperature exceeds 565°C, and the heat rapidly generated inside the synthesis device can be stored in the molten salt medium in the form of sensible heat, and the heat can be quickly transferred to the outside cavity through circulation, so as to avoid loss of temperature inside the synthesis device and ensure the stable operation of the reaction inside the synthesis device.

[0040] 6. Compared with the existing synthesis device, when the carbon monoxide content in the raw gas is high, in order to avoid the internal reaction of the synthesis device from being difficult to control, in the existing methanol synthesis technology, part of the carbon monoxide needs to be treated by steam reforming to convert the carbon monoxide into carbon dioxide and hydrogen, and then the carbon dioxide is removed, and the treated raw gas is synthesized into methanol; while the present invention adopts molten salt with high specific heat capacity and wide temperature range as the heat storage medium, which can effectively solve the problem that the raw gas cannot be directly introduced into the methanol synthesis device for reaction due to the high carbon monoxide content, and the generated reaction heat can be stored in the molten salt medium. The molten salt inside the heat storage medium tube bundle of the present invention is in a normal pressure state, and has the characteristics of low melting point, high boiling point, and large temperature range span, which is sufficient to absorb the reaction heat generated rapidly inside the synthesis device. Unlike the cooling water in the prior art, which is restricted by the drum pressure and the pressure bearing capacity of the internal pipeline, it cannot bear too much heat. The present invention can eliminate the carbon monoxide conversion process in the existing methanol synthesis process, thereby reducing the equipment investment in the conversion process, shortening the investment recovery period, and avoiding the emission of carbon dioxide in the existing methanol synthesis process, thereby improving the utilization rate of raw gas and increasing the methanol yield rate. The device has a high single-pass conversion rate.

[0041] 7. The molten salt in the heat storage medium tube bundle of the green alcohol synthesis device of the present invention flows from top to bottom, and the raw gas enters the inner cavity of the synthesis device from the raw gas distribution component and flows from bottom to top. This flow mode makes the heat exchange more sufficient and the heat absorption more complete; the reaction path of the raw gas along the flow direction of the intermediate axis is long, and the raw gas is in full contact with the catalyst, so that the raw gas reaction is more sufficient and the single-pass conversion rate of the raw gas is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a structural schematic diagram of a green alcohol synthesis device integrating molten salt heat transfer, heat storage and heat exchange according to the present invention;

[0043] Figure 2It is an overall schematic diagram of a green alcohol synthesis device integrating molten salt heat transfer, heat storage and heat exchange according to the present invention;

[0044] Figure 3 It is a schematic diagram of the structure of the support member and the fixing member of the present invention;

[0045] Figure 4 It is a schematic diagram of the oblique support structure of the present invention;

[0046] In the figure, 1, reaction shell; 2, heat exchange component; 3, cavity; 4, raw gas distribution component; 5, floating head; 6, inner cylinder; 7, outer cylinder; 8, oblique support; 9, inner cavity; 10, outer cavity; 11, heat storage medium tube bundle; 12, raw gas tube bundle; 13, lower head; 14, catalyst inlet; 15, catalyst unloading port; 16, heat storage medium outlet; 17, heat storage medium inlet; 18, raw gas inlet; 19, circulating pump; 20, support; 21, clamp; 22, intermediate shaft; 23, reaction cylinder; 24, raw gas reaction outlet; 801, upper pad; 802, oblique support rod; 803, lower pad; 401, raw gas elbow; 402, raw gas straight pipe; 403, raw gas distribution head. DETAILED DESCRIPTION

[0047] The present invention is further described below in conjunction with specific drawings, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of this patent.

[0048] The present invention provides a molten salt heat transfer, heat storage, heat exchange integrated green alcohol synthesis device (see Figure 1-4 ), the green alcohol synthesis device comprises a reaction shell 1, and a heat exchange component 2, a cavity 3, and a raw gas distribution component 4 arranged inside the reaction shell; the reaction shell 1 comprises a floating head 5, a reaction cylinder 23, and a lower head 13 from top to bottom; the floating head 5 is provided with a raw gas reaction outlet 24 and a catalyst feed inlet 14; the lower head 13 is provided with a catalyst discharge port 15 and a heat storage medium outlet 16; the reaction cylinder 23 is formed into a whole by an inner cylinder 6 and an outer cylinder 7; a raw gas inlet 18 is provided at the upper end of the outer cylinder 7;

[0049] The cavity 3 includes an inner cavity 9 formed by the inner wall of the inner cylinder 6 and the inner wall of the floating head 5, and an outer cavity 10 formed by the outer wall of the inner cylinder 6, the inner wall of the outer cylinder 7 and the inner wall of the lower head 13;

[0050] The outer cavity is provided with an inclined support 8 to provide support force for the inner cylinder. Four inclined supports are evenly arranged around the outer surface of the inner cylinder. The specific number of inclined supports can be set according to the total weight of the inner cylinder and the object carried inside the inner cylinder.

[0051] The heat exchange assembly 2 includes a heat storage medium tube bundle 11 located in the inner cavity 9 and a raw gas tube bundle 12 located in the outer cavity 10;

[0052] The raw gas distribution assembly 4 is composed of a raw gas elbow 401, a raw gas straight pipe 402, and a raw gas distribution head 403 connected by welding, and is located at the bottom of the inner cavity 9 surrounded by the inner cylinder 6;

[0053] A flange is welded at the lower end of the floating head 5, and a counter-flange matching the flange at the lower end of the floating head 5 is welded at the upper end of the inner cylinder 6. The flange of the floating head 5 and the counter-flange of the inner cylinder 6 are connected and fixed to the floating head 5 and the inner cylinder 6 by bolts, nuts and gaskets, which is a detachable connection; the outer cylinder 7 is welded and fixed and covered on the outer layer of the inner cylinder 6, and the upper edge of the outer cylinder 7 is 40 cm away from the flange end face of the inner cylinder 6; the lower end of the outer cylinder 6 is rigidly connected to the lower head 13 by welding; the inner cylinder 6 is in the form of a cylinder with a closed lower end and an open upper end;

[0054] The direction from the middle axis 22 to the outside is from inside to outside, and the direction pointing to the middle axis 22 is from outside to inside;

[0055] The raw gas pipe bundle 12 is located inside the outer cavity 10 and is arranged from top to bottom in a spirally coiled form, with the upper end being the start end of the coil and the lower end being the end end of the coil; each annularly wound coil is provided with a support member 20, and the support member 20 is based on the outer surface of the inner cylinder 6 as a base, and four support members 20 are evenly arranged at the same height with the middle axis 22 of the reaction shell 1 as the axis, and the angle between two adjacent support members 20 is 90°, and the length of the support member 20 in the radial direction (close to the side of the outer cylinder 7) pointing from the middle axis 22 to the outside can be the same as the width of the outer cavity 10 or extend to the raw gas pipe bundle 12 The support member 20 can support the raw gas pipe bundle 12 until it reaches the outside of the pipeline; a semicircular clamp 21 is provided outside the pipeline of the raw gas pipe bundle 12, and both ends of the clamp 21 are threaded, and one end with threads passes through the support member 20 and is fixedly connected to the support member 20 through a gasket and a nut; the raw gas pipe bundle 12 passes through the upper right end of the outer cylinder 7 and is connected to the raw gas inlet 18; the coil end of the raw gas pipe bundle 12 passes through the inner cavity 9 of the inner cylinder 6 from the bottom of the inner cylinder 6 and is connected to the raw gas distribution component 4 by welding;

[0056] The heat storage medium tube bundle 11 is located in the inner cavity 9 of the inner cylinder 6, and is arranged in a spiral coil from top to bottom along the middle axis 22 of the reaction shell 1, with the upper end being the start end of the coil and the lower end being the end end of the coil; the heat storage medium tube bundle 11 is fixed in a manner similar to that of the raw gas tube bundle 12, and each ring of the heat storage medium pipeline is provided with a fixing member (not shown), and the fixing member (not shown) is based on the inner surface of the inner cylinder 6 as a base, and 4 fixing members are evenly arranged at the same height with the middle axis 22 of the reaction shell 1 as the axis, and the angle between two adjacent fixing members is 90°, and the fixing member points to the radial direction of the middle axis 22 along the wall of the inner cylinder 6 (a direction away from the wall of the inner cylinder 6) The length of the fixing piece can be extended to the inner side of the pipe of the heat storage medium tube bundle 11, and the fixing piece can meet the function of supporting the heat storage medium tube bundle 11; a semicircular clamp 21 is arranged outside the pipe of the heat storage medium tube bundle 11, and threads are arranged at both ends of the clamp 21, and one end with threads passes through the fixing piece and is fixedly connected with the fixing piece through a gasket and a nut; the starting end of the coil of the heat storage medium tube bundle 11 is close to the flange surface at the upper end of the inner cylinder 6, passes through the wall surface of the inner cylinder 6 and is connected with the heat storage medium inlet 17; the end of the coil of the heat storage medium tube bundle 11 is connected to the outer cavity 10 from the wall surface of the inner cylinder 6 on one side close to the bottom of the inner cylinder 6;

[0057] The heat storage medium outlet 16 is connected to the inlet of a circulation pump 19 through an external pipeline, and the outlet of the circulation pump 19 is connected to the heat storage medium inlet 17 through an external pipeline.

[0058] Specifically, the outer cavity 10 and the heat storage medium tube bundle 11 are both filled with heat storage medium;

[0059] In this embodiment, the outer cavity 10 provides a carrying space for the heat storage medium. The heat storage medium inside the outer cavity 10 has two main functions: on the one hand, it absorbs the heat transmitted from the wall of the inner cylinder 6; on the other hand, it transmits the heat absorbed from the inner cavity 9 to the raw gas and exchanges heat with the raw gas. The heat storage medium in the heat storage medium tube bundle 11 has two main functions: on the one hand, it absorbs and moves the reaction heat of the inner cavity 9 to the outer cavity 10 to ensure the reaction temperature of the inner cavity 9; on the other hand, it stores the strong reaction heat generated quickly by the inner cavity 9.

[0060] In this embodiment, the raw gas distribution component 4 is provided with a raw gas elbow 401, which can effectively prevent the raw gas from passing directly into the inner cavity 9, causing the catalyst to block the raw gas pipeline; the raw gas distribution head 403 is installed at the end of the raw gas straight pipe 402, and the structural form is a spherical mesh structure, which makes its surface evenly stressed and not easy to be damaged;

[0061] In this embodiment, the raw gas tube bundle 12 and the heat storage medium tube bundle 11 are both made of seamless stainless steel pipes, and the materials of the seamless stainless steel pipes include but are not limited to 316, 347, and 348; the inner cylinder 6, the outer cylinder 7, the lower head 13, and the floating head 5 can be made of Q345R or Q370R, but are not limited to the above materials. The reaction shell material is required to have high strength, high heat resistance, oxidation resistance, and easy welding.

[0062] In this embodiment, multiple thermocouples (not shown in the figure) are arranged from top to bottom along the inner surface of the inner cylinder 6 to monitor the internal temperature of the inner cylinder in real time;

[0063] Specifically, the circulation pump 19 is a high temperature resistant variable frequency molten salt pump, which controls the frequency of the circulation pump 19 by receiving the temperature signal sent by the multi-point thermocouple, thereby controlling the flow speed of the molten salt in the heat storage medium tube bundle 11 and adjusting the heat transfer rate;

[0064] In this embodiment, when the raw gas contacts and reacts with the catalyst in the inner cavity 9, the multi-point thermocouples in the inner cavity 9 monitor the temperature changes in real time. When a sharp change in the temperature inside the synthesis device is detected, the multi-point thermocouples transmit the temperature signal to the circulation pump 19. After receiving the temperature signal, the circulation pump 19 increases the speed of the circulation pump, thereby increasing the circulation speed of the heat storage medium, further accelerating the removal of heat from the synthesis device, and providing protection for the safe operation of the synthesis device.

[0065] Furthermore, the inclined support 8 includes a lower pad 803, an upper pad 801, and an inclined support rod 802. The lower pad is made into a pad having the same curvature as the inner surface of the lower head, and the lower pad is fully welded to the lower head. The upper pad is made into a pad having the same curvature as the outer surface of the inner cylinder, and the upper pad is fully welded to the inner cylinder. Both ends of the inclined support rod are respectively welded to the upper pad and the lower pad, and the angle between the inclined support and the outer surface of the inner cylinder is between 30-45°.

[0066] Furthermore, the heat storage medium inlet is arranged on the side wall of the outer surface of the inner cylinder, between the upper end edge of the outer cylinder and the flange end surface of the inner cylinder, located at the upper right end of the reaction shell, and the heat storage medium inlet is welded to the wall surface of the inner cylinder.

[0067] Furthermore, the raw gas inlet is arranged on the side wall of the outer surface of the outer cylinder, located at the upper right end of the outer cylinder, directly below the heat storage medium inlet, and the raw gas inlet is welded to the wall of the outer cylinder.

[0068] Furthermore, the heat storage medium outlet is located on the lower right side of the outer surface of the lower head, penetrates the lower head and is fixed to the contact part with the lower head by welding. The heat storage medium outlet is located directly below the raw gas inlet and the heat storage medium inlet.

[0069] Furthermore, the catalyst feed inlet is located on the right side of the floating head at an angle of 45°, the catalyst feed inlet is connected to the contact position of the floating head by welding, and the catalyst feed inlet is blocked by a blind plate during use of the synthesis device.

[0070] Furthermore, the catalyst discharge port and the raw gas reaction outlet are installed on the middle shaft of the reaction shell.

[0071] Furthermore, the starting end of the coil of the heat storage medium tube bundle is close to the flange surface at the upper end of the inner cylinder, penetrates the wall of the inner cylinder and is connected to the heat storage medium inlet; the end of the coil of the heat storage medium tube bundle is connected to the outer cavity from the wall of the inner cylinder on one side close to the bottom of the inner cylinder.

[0072] The working principle of the green alcohol synthesis device of the present invention which integrates molten salt heat transfer, heat storage and heat exchange is as follows:

[0073] The raw gas is introduced into the raw gas tube bundle 12 from the raw gas inlet 18, and the raw gas rotates and flows from top to bottom in the raw gas tube bundle 12. The high-temperature molten salt inside the outer cavity 10 transfers heat to the outer wall of the raw gas tube bundle 12 by convection heat exchange. The outer wall of the raw gas tube bundle 12 transfers heat to the inner wall by heat conduction. The temperature of the inner wall increases, and the raw gas takes away the heat of the inner wall of the raw gas tube bundle 12 by convection heat exchange to increase the internal energy of the raw gas, thereby increasing the temperature of the raw gas; the heated raw gas is introduced into the inner cavity 9 of the reaction shell by the raw gas distribution component 4, and the raw gas generates methanol gas under the action of the catalyst in the inner cavity 9. The generated methanol gas is discharged from the raw gas reaction outlet 24 on the upper part of the floating head 5 and is subsequently purified. When the raw gas generates methanol gas, a large amount of reaction heat is released, and the generated reaction heat is stored and absorbed by the molten salt in the heat storage medium tube bundle 11 in the form of sensible heat;

[0074] The molten salt stored in the outer cylinder 7 is pumped out by the circulation pump 19 after heat exchange, and is passed into the heat storage medium bundle 11 of the inner cavity 9 through the heat storage medium inlet 17. The reaction heat generated by the reaction of the raw gas in the inner cavity 9 of the reaction shell 1 is transferred to the outer surface of the heat storage medium bundle 11 through convection heat exchange, and the heat on the outer surface of the heat storage medium bundle 11 is transferred to the inner surface in the form of heat conduction. The molten salt rotates from top to bottom in the heat storage medium bundle 11, and takes away the heat from the inner surface in the form of convection heat exchange, so that the internal energy of the molten salt increases, and the temperature of the molten salt rises. The high-temperature molten salt is then passed into the outer cavity 10 from the end of the coil of the heat storage medium bundle to heat the raw gas.

[0075] When the raw gas contacts and reacts with the catalyst in the inner cavity 9, the multi-point thermocouples in the inner cavity 9 monitor the temperature change in real time. When a sharp change in the temperature inside the synthesis device is detected, the multi-point thermocouples transmit the temperature signal to the circulation pump 19. After receiving the temperature signal, the circulation pump 19 increases the speed of the circulation pump, thereby increasing the circulation speed of the heat storage medium, further accelerating the removal of heat from the synthesis device, and providing protection for the safe operation of the synthesis device.

[0076] Any matters not described in the present invention are applicable to the prior art.

Claims

1. A molten salt heat transfer, heat storage, and heat exchange integrated green alcohol synthesis device, comprising a reaction shell, and a heat exchange component, a cavity, and a raw gas distribution component arranged inside the reaction shell, characterized in that: The reaction shell comprises a floating head, a reaction cylinder and a lower end cap from top to bottom; the floating head is provided with a raw gas reaction outlet and a catalyst inlet; the lower end cap is provided with a catalyst discharge port and a heat storage medium outlet; the reaction cylinder is formed as a whole by an inner cylinder and an outer cylinder; The cavity includes an inner cavity formed by the inner wall of the inner cylinder and the inner wall of the floating head, and an outer cavity formed by the outer wall of the inner cylinder, the inner wall of the outer cylinder and the inner wall of the lower head; The heat exchange assembly includes a heat storage medium tube bundle in the inner cavity and a raw gas tube bundle in the outer cavity; The raw gas distribution assembly is located at the bottom of the inner cavity surrounded by the inner cylinder; A heat storage medium inlet is arranged on the inner cylinder, and the heat storage medium is located at the lower part of the connection position between the inner cylinder and the floating head, and at the upper part of the outer cylinder; A raw gas inlet is arranged at the upper part of the outer cylinder; The raw gas pipe bundle is located inside the outer cavity and is arranged from top to bottom in a spirally coiled form, the upper end of the coil is the start end, connected to the raw gas inlet, and the lower end is the end of the coil, connected to the raw gas distribution assembly in the inner cylinder; each ring of the raw gas pipe bundle is fixed to the inner wall of the outer cylinder and / or the outer wall of the inner cylinder through a support; The heat storage medium tube bundle is located in the inner cavity of the inner cylinder, and is arranged in a spiral shape along the middle axis of the reaction shell from top to bottom. The upper end is the start end of the coil, which is connected to the heat storage medium inlet, and the lower end is the end of the coil, which passes through the inner cylinder and communicates with the outer cavity; each ring of the heat storage medium tube bundle is fixed to the inner wall of the inner cylinder through a support; The heat storage medium outlet is connected to the circulation pump inlet through an external pipeline, and the circulation pump outlet is connected to the heat storage medium inlet through an external pipeline; the outer cavity and the heat storage medium tube bundle are filled with molten salt heat storage medium.

2. The molten salt heat transfer, heat storage and heat exchange integrated green alcohol synthesis device according to claim 1 is characterized in that: A flange is welded at the lower end of the floating head, and a counter-flange matching the flange at the lower end of the floating head is welded at the upper end of the inner cylinder. The floating head flange and the counter-flange of the inner cylinder are connected and fixed to the floating head and the inner cylinder by bolts, nuts and gaskets, which is a detachable connection; the outer cylinder is welded and fixed and covered on the outer layer of the inner cylinder, and the upper edge of the outer cylinder is 30-50cm away from the flange end face of the inner cylinder; the lower end of the outer cylinder is rigidly connected to the lower head by welding; the inner cylinder is in the form of a cylinder with a closed lower end and an open upper end.

3. The molten salt heat transfer, heat storage and heat exchange integrated green alcohol synthesis device according to claim 1, characterized in that: The raw gas distribution assembly is composed of a raw gas elbow, a raw gas straight pipe and a raw gas distribution head welded together, and the raw gas elbow is connected to the lower coil end of the raw gas pipe bundle; preferably, the raw gas distribution head adopts a spherical mesh structure.

4. The molten salt heat transfer, heat storage and heat exchange integrated green alcohol synthesis device according to claim 1, characterized in that: The support members at the same height are evenly distributed along the circumferential direction, and the support members have a horizontal support surface, and the winding coil is fixed on the horizontal support surface by a semicircular clamp; the length of the support member in the outer cavity is the same as the width of the outer cavity or extends from the outer wall of the inner cylinder to the outer side of the pipe of the winding coil of the raw gas pipe bundle, and the length of the support member in the inner cavity is from the inner wall of the inner cylinder to the inner side of the pipe of the winding coil of the heat storage medium pipe bundle, and the support member can meet the function of supporting the raw gas pipe bundle / heat storage medium pipe bundle.

5. The molten salt heat transfer, heat storage and heat exchange integrated green alcohol synthesis device according to claim 1, characterized in that: The straight pipe section of the catalyst discharge port passes through the lower end cap and the bottom end of the inner cylinder in sequence and communicates with the inner cavity. The straight pipe section of the catalyst discharge port is connected to the lower end cap and the bottom end of the inner cylinder at the contact point by welding; the catalyst discharge port is blocked by a blind plate during the use of the synthesis device; The catalyst is filled in the inner cavity formed by the inner wall of the inner cylinder and the inner wall of the floating head, and the filling coefficient reaches 80%.

6. The molten salt heat transfer, heat storage and heat exchange integrated green alcohol synthesis device according to claim 1, characterized in that: The outer cavity is provided with oblique supports to provide support force for the inner cylinder, and the oblique supports are evenly arranged around the outer surface of the inner cylinder, and the specific number of oblique supports is set according to the total weight of the inner cylinder and the object carried inside the inner cylinder; The oblique support includes a lower pad, an upper pad, and an oblique support rod. The lower pad is made into a pad with the same curvature as the inner surface of the lower head, and the lower pad is fully welded to the lower head. The upper pad is made into a pad with the same curvature as the outer surface of the inner cylinder, and the upper pad is fully welded to the inner cylinder. The two ends of the oblique support rod are respectively welded to the upper pad and the lower pad; preferably, the angle between the oblique support and the outer surface of the inner cylinder is between 30-45°.

7. The molten salt heat transfer, heat storage and heat exchange integrated green alcohol synthesis device according to claim 1, characterized in that: The bottom of the inner cylinder is configured as a dome structure to facilitate catalyst unloading; The heat storage medium is binary salt or ternary salt molten salt.

8. The molten salt heat transfer, heat storage and heat exchange integrated green alcohol synthesis device according to claim 1, characterized in that: The spacing between upper and lower adjacent pipes in the same type of raw gas pipe bundle and heat storage medium pipe bundle is 3-6 cm.

9. The molten salt heat transfer, heat storage and heat exchange integrated green alcohol synthesis device according to claim 1, characterized in that: Multiple thermocouples are arranged from top to bottom along the inner surface of the inner cylinder to monitor the internal temperature of the inner cylinder in real time; the circulation pump is a high-temperature resistant variable-frequency molten salt pump, which controls the circulation pump frequency by receiving the temperature signal emitted by the multiple thermocouples, thereby controlling the flow speed of the molten salt in the heat storage medium tube bundle and adjusting the heat transfer rate.

10. The molten salt heat transfer, heat storage and heat exchange integrated green alcohol synthesis device according to claim 1, characterized in that: The working principle of the green alcohol synthesis device is: The raw gas is introduced into the raw gas bundle from the raw gas inlet, and the raw gas rotates and flows from top to bottom in the raw gas bundle. The high-temperature molten salt inside the outer cavity transfers heat to the outer wall of the raw gas bundle by convection heat exchange. The outer wall of the raw gas bundle transfers heat to the inner wall by heat conduction. The temperature of the inner wall increases, and the raw gas takes away the heat of the inner wall of the raw gas bundle by convection heat exchange to increase the internal energy of the raw gas, thereby increasing the temperature of the raw gas; the heated raw gas is introduced into the inner cavity of the reaction shell by the raw gas distribution component, and the raw gas generates methanol gas under the action of the catalyst in the inner cavity. The generated methanol gas is discharged from the raw gas reaction outlet on the upper part of the floating head and is subsequently purified. When the raw gas generates methanol gas, a large amount of reaction heat is released, and the generated reaction heat is stored and absorbed by the molten salt in the heat storage medium bundle in the form of sensible heat; The molten salt stored in the outer cylinder is pumped out by the circulation pump after heat exchange, and is passed into the heat storage medium bundle in the inner cavity through the heat storage medium inlet; the reaction heat generated by the reaction of the raw gas in the inner cavity of the reaction shell is transferred to the outer surface of the heat storage medium bundle through convection heat exchange, and the heat on the outer surface of the heat storage medium bundle is transferred to the inner surface in the form of heat conduction. The molten salt rotates from top to bottom in the heat storage medium bundle, and takes away the heat on the inner surface in the form of convection heat exchange, so that the internal energy of the molten salt increases, and the temperature of the molten salt rises. The high-temperature molten salt is then passed into the outer cavity from the end of the coil of the heat storage medium bundle to heat the raw gas; When the raw gas contacts and reacts with the catalyst in the inner cavity, the multi-point thermocouples in the inner cavity monitor the temperature changes in real time. When a sharp change in the temperature inside the synthesis device is detected, the multi-point thermocouples transmit the temperature signal to the circulation pump. After receiving the temperature signal, the circulation pump increases the speed of the circulation pump, thereby increasing the circulation speed of the heat storage medium, further accelerating the removal of heat from the synthesis device, and providing protection for the safe operation of the synthesis device.

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