Gas phase loading system and method and their applications

Abstract

The present invention provides a method and system for gas-phase loading and its application. The method comprises: heating a load with a carrier gas and mixing it with a gas-phase load material, performing a first heat exchange, then performing a second heating and then contacting the carrier for gas-phase loading; using the load tail gas as a first heat exchange source, performing heat exchange, condensing the load tail gas, and then contacting the load tail gas with an absorbent for absorption; performing a first condensation on the absorbent tail gas, then performing a first cooling and then adsorption, and pressurizing the adsorbed gas and recovering it as a recycled carrier gas for recycling. The present invention overcomes the technical defects of conventional gas-phase loading equipment in which the load material is solid, the catalyst and the load source are in the same equipment, the equipment space utilization is low, the catalyst loading amount is small, and it is not conducive to reducing the labor intensity of catalyst unloading; and the present invention further overcomes the technical defects of using a carrier gas to heat the load source to gasify the loaded catalyst, which makes it impossible to measure the flow rate and load amount of the load material, which has a significant impact on the catalyst loading results.

Description

Technical Field

[0001] The present invention relates to a process for loading activation and control means in the process, and in particular to a system and method for gas-phase loading of a catalyst and the application of the gas-phase loading method or the gas-phase loading system in catalyst preparation. Background Art

[0002] A catalyst is a substance that effectively promotes a reaction and increases its rate without changing itself. To effectively improve catalyst performance or extend its lifespan, other active substances are loaded onto the original catalyst. Current methods for catalyst loading include impregnation, sedimentation, ion exchange, and chemical vapor deposition.

[0003] The impregnation method involves immersing the catalyst support in the loading material. This method is further subdivided into wet impregnation, which includes equal volume wet impregnation and excess impregnation; dry impregnation, which repeats the impregnation, drying, and calcination steps; vacuum impregnation, which first evacuates the porous material before adding the impregnation liquid; and pressurized impregnation, which uses pressure to maximize the loading material's penetration into the pores. This method is simple to produce and offers high throughput, but can cause migration of active components during drying.

[0004] Sedimentation precipitation involves first immersing the catalyst support in a loading solution, followed by the addition of a precipitant. This method is primarily used to prepare precious metal catalysts. This process is difficult to control, as precipitation tends to occur in the liquid phase rather than the support, leading to poor reproducibility.

[0005] The ion exchange method exchanges the active substances in the supported material with some of the ions on the catalyst support surface. The supported catalyst is then washed, dried, and calcined to produce the supported catalyst. This method produces catalysts with uniformly dispersed active components and high activity, making it more suitable for the preparation of precious metal catalysts and acid-base catalysts.

[0006] Chemical vapor deposition is a technology that uses substances in gas or vapor state to react in the gas phase or at the gas-solid interface to form solid deposits. This technology is mainly applicable to the following situations: the reaction raw materials are gas phase or liquid or solid substances that are easily volatilized into vapor; the reaction easily generates the desired precipitate, and the by-products can be discharged with the gas phase or easily separated.

[0007] Nowadays, there are few processes for preparing supported catalysts by the gas phase method. However, compared with methods such as impregnation and ion exchange, the catalyst prepared by this process is in a dry state, which reduces the catalyst purging and drying process and simplifies the catalyst production process. On the other hand, the moisture content of the catalyst is low, which reduces the labor intensity of loading, unloading and transporting the catalyst.

[0008] CN103934042A discloses a vapor deposition preparation method for a supported iron catalyst, which mainly includes the steps of catalyst loading, placement of a ferrocene pile, deposition of the supported material, and calcination. This technology can prepare a highly dispersed supported iron catalyst, but the loading of the catalyst in the reactor is relatively difficult and the sealing is poor, which is not conducive to safe operation.

[0009] CN103949256A discloses a method for preparing a supported nickel catalyst by vapor deposition, which mainly includes loading the catalyst and placing the loaded material, inert gas reduction, vapor deposition loading, and reduction steps. This process does not involve the preparation of solutions, so there is no waste liquid generated, and the process is relatively convenient. However, the loaded material in this device is solid, and the catalyst and the load source are in the same device. The space utilization rate of the device is low, and the catalyst loading amount is small, which is not conducive to reducing the labor intensity of catalyst unloading. Secondly, the loaded catalyst is vaporized by using a carrier gas to heat the load source. The flow rate and load amount of the loaded material cannot be measured, which has a significant impact on the catalyst loading result.

[0010] CN203990659U discloses a simple device system for a loaded catalyst, which mainly includes a carrier gas system, a loading system and an exhaust gas treatment system. The gasification of the loading source depends on the heating of the carrier gas. A large amount of carriers need to be introduced during the early preheating process, and the carrier gas in the exhaust gas is not further recovered, resulting in a waste of carrier gas. Secondly, the catalyst loading process is accompanied by heat release or heat absorption. Only the catalyst and the loading bed are temperature-monitored without corresponding control measures, which has great limitations on the safe loading of the catalyst. In this simple device, the catalyst is loaded into a stainless steel mesh box and then loaded into a reactor. The operation is relatively complicated and increases investment to a certain extent. Summary of the Invention

[0011] The purpose of the present invention is to provide a new gas phase loading method and system to address the technical deficiencies in the prior art.

[0012] According to a first aspect of the present invention, the present invention provides a gas phase loading method, the method comprising:

[0013] The gas-phase loaded material is optionally heated and then sent into a loading unit to contact with a carrier for gas-phase loading. The contact is optionally carried out in the presence of a carrier gas for loading. The loaded tail gas is recovered and treated to recover the carrier gas.

[0014] According to a second aspect of the present invention, the present invention provides a gas phase loading system, the system comprising: a loading unit, the loading unit comprising:

[0015] A raw material storage tank, a heat exchanger, a heater, and a load tower connected in series;

[0016] and a carrier gas heater;

[0017] Among them, the gas phase outlet of the raw material storage tank is connected to the inlet of the heat exchanger, the outlet of the heat exchanger is connected to the heater, the gas phase outlet of the heater is connected to the gas phase inlet of the load tower, the gas phase outlet of the load tower is connected to the inlet of the heat exchanger, and the carrier gas heater is connected to the gas phase outlet of the raw material storage tank and the inlet of the heat exchanger;

[0018] Wherein, the raw material storage tank is used to gasify the loaded material to obtain the gaseous loaded material;

[0019] Among them, the carrier gas heater is used to heat the load with carrier gas and mix it with the gas-phase load material to enter the heat exchanger for the first heat exchange, and then enter the heater for the second heating and then enter the load tower to contact with the carrier for gas-phase loading; the load exhaust gas flows out through the gas-phase outlet of the load tower and passes through the heat exchanger for the first heat exchange.

[0020] According to a third aspect of the present invention, the present invention provides a gas phase loading method, which is carried out in the system of the present invention.

[0021] According to a fourth aspect of the present invention, the present invention provides use of the gas-phase loading method or the gas-phase loading system of the present invention in catalyst preparation.

[0022] Compared with the gas phase loading in the prior art, the present invention uses gas phase loading material to be vaporized and then sent into the loading unit for loading with the carrier, overcoming the technical defects of the traditional gas phase loading equipment in which the loading material is solid, the catalyst and the loading source are in the same equipment, the equipment space utilization rate is low, the catalyst loading amount is small, and it is not conducive to reducing the labor intensity of catalyst unloading; and the present invention further overcomes the technical defects of using carrier gas to heat the loading source to gasify the loaded catalyst, the flow rate and loading amount of the loaded material cannot be measured, and has a significant impact on the catalyst loading result.

[0023] The gas phase method for preparing supported catalysts of the present invention involves the entire process of catalyst preparation, including process control means, tail gas absorption, carrier recovery and other processes, and provides a process means for preparing supported catalysts by the gas phase method that is simple to operate and has strong applicability.

[0024] Compared with the wet impregnation loading in the prior art, the present invention overcomes the following technical defects: 1) It overcomes the technical defects of the prior art catalyst liquid phase loading, such as large amount of wastewater and complicated treatment process; 2) It overcomes the technical defect that after the catalyst liquid phase loading, the moisture content of the catalyst is high, which is not conducive to the unloading and transfer of the catalyst; 3) It overcomes the technical defect that during the catalyst liquid phase loading process, corresponding roasting and activation equipment is required, the operation is relatively complicated, and the corresponding equipment investment is increased.

[0025] Furthermore, according to preferred embodiments of the present invention, a comprehensive vapor-phase loading system and method have been developed for the first time. Existing vapor-phase methods for preparing supported catalysts only cover the catalyst preparation process, without addressing the control methods and overall process during the loading process, significantly limiting the industrial application of such processes. The system and method of the present invention can be directly used in industrial production and have high industrial application value.

[0026] Compared with traditional loading methods, the present invention is safer and more environmentally friendly, and consumes less carrier gas and loading material.

[0027] The supported catalyst of the present invention is used in industrial production, and the conversion rate and selectivity both reach the expected effect, with satisfactory results. In addition, the carrier gas recovery unit used in the present invention reduces the amount of nitrogen consumed by at least 2 times. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a gas phase loading system according to a preferred embodiment of the present invention.

[0029] Description of Reference Numerals

[0030] I is the raw material storage tank; II is the heat exchanger;

[0031] III is a heater; IV is a load tower;

[0032] V is the carrier gas heater; VI is the tail gas condenser;

[0033] VII is the absorption system; VIII is the gas condenser;

[0034] IX is a gas subcooler; X is an adsorption tower;

[0035] XI is a buffer tank; XII is a fan.

[0036] 2 is carrier gas; 3 is gas phase loaded substance; 6 is tail gas loaded; 9 is tail gas absorption; 14 is carrier gas recovery; 15 is condensate; 16 is absorption waste liquid; 17 is absorption tail gas condensate, and 18 is absorption tail gas condensate coolant. DETAILED DESCRIPTION

[0037] The present invention will be further described below by way of examples, but is not limited thereto.

[0038] The present invention provides a method for gas phase loading, which comprises: optionally heating a gas phase loading material and then sending it into a loading unit to contact with a carrier for gas phase loading, wherein the contact is optionally carried out in the presence of a carrier gas for loading, and recovering the loaded tail gas to recover the carrier gas.

[0039] Compared with the gas-phase loading in the prior art, the gas-phase loading of the present invention uses a gas-phase loading material to be vaporized and then sent into a loading unit with a carrier for loading. This overcomes the technical defects of traditional gas-phase loading equipment in which the loading material is solid, the catalyst and the loading source are in the same equipment, the equipment space utilization rate is low, the catalyst loading amount is small, and it is not conducive to reducing the labor intensity of catalyst unloading. The present invention further overcomes the technical defects of using carrier gas to heat the loading source to gasify the loaded catalyst, the flow rate and loading amount of the loaded material cannot be measured, and has a significant impact on the catalyst loading result.

[0040] In the present invention, there is no special requirement for the loading material, and commonly used loading materials can be loaded using the method of the present invention. For the present invention, the loading material is preferably a metal salt compound, and the boiling point is preferably 50-300°C.

[0041] In the present invention, there is no special requirement for the carrier gas used for loading, and any commonly used carrier gas can be loaded using the method of the present invention. For the present invention, the carrier gas used for loading is preferably an inert protective gas, preferably nitrogen.

[0042] In the present invention, the mass flow rate ratio of the gaseous loading substance to the loading carrier gas can be selected in a wide range, and is preferably 0.1 to 3. The aforementioned mass flow rate ratio not only allows for better loading, but also enables good carrier gas recovery.

[0043] In the present invention, the gas phase loading conditions can be adjusted according to specific needs. According to a preferred embodiment of the present invention, the gas phase loading conditions include: 200-800°C.

[0044] In the present invention, the purpose of the recycling process is to recover the carrier. Therefore, according to a preferred embodiment of the present invention, the recycling process includes: condensation, absorption, first condensation, adsorption after first cooling, and then pressurization recovery and recycling after passing through a buffer tank.

[0045] According to a preferred embodiment of the present invention, the method of the present invention comprises:

[0046] The load is heated with a carrier gas and mixed with a gas-phase load material, and then subjected to a first heat exchange, and then subjected to a second heating and contact with a carrier for gas-phase loading; the load tail gas is used as a first heat exchange source, and then condensed and contacted with an absorbent for absorption; the absorbed tail gas is subjected to a first condensation, and then subjected to a first cooling and then adsorption, and the adsorbed gas is pressurized and recovered after passing through a buffer tank to obtain a recovered carrier gas.

[0047] According to the above process, the gas phase loading can be effectively carried out and the carrier gas can be well recovered. The gas phase method for preparing a supported catalyst of the present invention involves the entire process of catalyst preparation, including the control means, tail gas absorption, carrier recovery and other processes in the process, and provides a process method for preparing a supported catalyst by the gas phase method that is simple to operate and has strong applicability.

[0048] In the present invention, the conditions of each step can be adjusted according to specific load requirements and processing technology. The following examples list preferred implementations, but they do not limit the scope of the present invention.

[0049] According to a preferred embodiment of the present invention, the conditions for heating the carrier gas include: 80-300°C, preferably 100-200°C.

[0050] According to a preferred embodiment of the present invention, the first heat exchange condition includes: 100-500°C.

[0051] According to a preferred embodiment of the present invention, the second heating condition includes: 200-700°C.

[0052] According to a preferred embodiment of the present invention, the conditions for condensation of the loaded tail gas after heat exchange include: 45-150°C.

[0053] According to a preferred embodiment of the present invention, the conditions for the first condensation include: a temperature of 40-70°C.

[0054] According to a preferred embodiment of the present invention, the first cooling condition includes: -60°C to -30°C.

[0055] According to a preferred embodiment of the present invention, the absorption conditions include: 20-60°C.

[0056] According to a preferred embodiment of the present invention, the absorbent is one or more of acid, alkali and water.

[0057] According to a preferred embodiment of the present invention, the adsorption conditions include: one or more dehydrating adsorbents, the volume space velocity is preferably 1 to 5h -1 .

[0058] According to a preferred embodiment of the present invention, the buffering conditions include: -60°C to 40°C.

[0059] According to a preferred embodiment of the present invention, after the gas phase loading is completed, the carrier is calcined using heated carrier gas to complete the regeneration.

[0060] The present invention has previously introduced a gas phase loading method with a full process flow, which can be directly used in industry and has high industrial application value.

[0061] like Figure 1 As shown, according to a preferred embodiment of the present invention, the present invention provides a gas phase loading system, the system comprising: a loading unit, the loading unit comprising: a raw material storage tank I, a heat exchanger II, a heater III, and a loading tower IV connected in series in sequence;

[0062] and a carrier gas heater V;

[0063] Among them, the gas phase outlet of the raw material storage tank I is connected to the inlet of the heat exchanger II, the outlet of the heat exchanger II is connected to the heater III, the gas phase outlet of the heater III is connected to the gas phase inlet of the load tower IV, the gas phase outlet of the load tower IV is connected to the inlet of the heat exchanger II, and the carrier gas heater V is connected to the gas phase outlet of the raw material storage tank I and the inlet of the heat exchanger II;

[0064] Wherein, the raw material storage tank 1 is used to gasify the loaded material to obtain the gaseous loaded material;

[0065] Among them, the carrier gas heater V is used to heat the load with carrier gas and mix it with the gas-phase load material to enter the heat exchanger II for the first heat exchange, then enter the heater III for the second heating, and then enter the load tower IV to contact the carrier for gas-phase loading; the load exhaust gas flows out through the gas phase outlet of the load tower IV and passes through the heat exchanger II for the first heat exchange.

[0066] The use of the aforementioned load unit has the advantages of simple control, low consumption of load materials, and less emission of three wastes.

[0067] According to a preferred embodiment of the present invention, the system further comprises:

[0068] A tail gas treatment unit, comprising a tail gas condenser VI (for gas phase liquefaction treatment / recovery of excess raw materials) and an absorption tower VII connected in series; the inlet of the tail gas condenser VI is connected to the outlet of the heat exchanger II; the outlet of the tail gas condenser VI is connected to the inlet of the absorption tower VII;

[0069] The loaded tail gas flows out of the gas phase outlet of load tower IV, undergoes the first heat exchange in heat exchanger II, and then enters tail gas condenser VI for condensation. It then enters absorption tower VII for absorption by the absorbent. The aforementioned tail gas treatment unit has the advantages of recovering the loaded material, reducing load material consumption, and reducing the loaded material content in the carrier gas.

[0070] According to a preferred embodiment of the present invention, preferably, the system further includes: a gas recovery unit, wherein the gas recovery unit includes: a gas condenser VIII, a gas subcooler IX, an adsorption tower X, a buffer tank XI, and a fan XII connected in series in sequence; the use of the aforementioned gas recovery unit has the advantage of reducing carrier gas consumption.

[0071] In the present invention, each unit and each structure in the unit can be equipped with flow control valves, temperature measuring, pressure measuring components and the like as needed, such as the present invention Figure 1 As shown, S.1, S.2, and S.3 are control valves on different pipelines, TC is used to control the load temperature of the load tower, FC is used to control the gas phase evaporation amount of the load material, and WC is used to control the liquid phase weight of the load material.

[0072] The present invention has no special requirements for the arrangement of the load tower, raw material storage tank, heat exchanger, absorption tower, adsorption tower, and buffer tank. The purpose of the present invention can be effectively achieved by installing them according to the above requirements. The following schematically illustrates their arrangement, but this does not limit the scope of the present invention.

[0073] According to a preferred embodiment of the present invention, preferably, the load tower IV is provided with a gas inlet and a carrier loading port at the top; the bottom is provided with an inverted cone shape, a catalyst unloading port is provided at the bottom, and a gas outlet is provided on the side.

[0074] According to a preferred embodiment of the present invention, preferably, the catalyst discharge port adopts a flap-type flange cover, and the side gas outlet is filled with a wire mesh.

[0075] According to a preferred embodiment of the present invention, the raw material storage tank 1 is provided with a top gas phase outlet, and the raw material storage tank 1 is configured to be self-heating, and the load material is heated to a gas phase in the raw material storage tank 1;

[0076] According to a preferred embodiment of the present invention, preferably, the self-heating method adopts a coil or a jacket; the heating medium is preferably steam and / or heat conduction; preferably, the outlet pipeline of the raw material storage tank 1 adopts insulation or heat tracing to prevent the vaporized gas from condensing into liquid in the pipeline;

[0077] In the present invention, heating refers to electric heating or steam heating to prevent the loaded material from condensing in the pipeline after being gasified.

[0078] According to a preferred embodiment of the present invention, preferably, the heat exchanger II is configured as a heat flow tube side; preferably, the carrier gas heater V is connected to the shell side inlet of the heat exchanger II, the gas phase outlet of the raw material storage tank I is connected to the shell side inlet of the heat exchanger II, and the gas phase outlet of the load tower IV is connected to the tube side inlet of the heat exchanger II; the shell side outlet of the heat exchanger II is connected to the heater III.

[0079] According to a preferred embodiment of the present invention, preferably, the heat exchanger (II) is a shell and tube heat exchanger.

[0080] According to a preferred embodiment of the present invention, preferably, the absorption tower includes one or more of an acid absorption tower, an alkali absorption tower, and a water absorption tower.

[0081] According to a preferred embodiment of the present invention, preferably, the absorption tower VII is provided with a side wall inlet, a top outlet and a bottom outlet.

[0082] According to a preferred embodiment of the present invention, the adsorption tower X is provided with a bottom inlet and a top outlet.

[0083] According to a preferred embodiment of the present invention, the buffer tank XI is provided with a top inlet.

[0084] The present invention provides a method for gas phase loading, which is performed in the system of the present invention. Performing the gas phase loading in the full system of the present invention has the advantages of simple control, low consumption of loading materials, low emission of three wastes, and low consumption of carrier gas.

[0085] According to a preferred embodiment of the present invention, the method comprises:

[0086] The carrier gas heater V heats the carrier gas 2 and mixes it with the gaseous load material 3 from the raw material storage tank I. The mixture enters the heat exchanger II for the first heat exchange, then enters the heater III for the second heating, and then enters the load tower IV to contact the carrier for gaseous loading. The loaded exhaust gas 6 flows out from the gas phase outlet of the load tower IV, exchanges heat through the heat exchanger II, and is sent to the exhaust gas treatment unit.

[0087] After condensation in tail gas condenser VI, it enters absorption tower VII and contacts with absorbent for absorption;

[0088] The absorption tail gas 9 discharged from the absorption tower VII enters the gas condenser VIII for the first condensation, then enters the gas subcooler IX for the first cooling, and then enters the adsorption tower X for adsorption. The gas discharged from the adsorption tower X enters the buffer tank XI for fan boosting and recovery to obtain the recovered carrier gas 14, and the fan XII boosts the pressure of the buffer tank XI.

[0089] According to the method of the present invention, the method further includes: discharging condensate 15 from the tail gas condenser VI, discharging absorption waste liquid 16 from the absorption tower VII, discharging absorption tail gas condensate 17 from the gas condenser VIII, and discharging absorption tail gas condensate cooling liquid 18 from the gas subcooler IX.

[0090] The above-mentioned loading method has the advantages of simple control, less consumption of loading materials, less discharge of three wastes, and less consumption of carrier gas.

[0091] In the present invention, the operating conditions of each unit can be adjusted according to specific load requirements and processing technology. The following examples list preferred implementations, but they do not limit the scope of the present invention.

[0092] According to a preferred embodiment of the present invention, the operating conditions of the carrier gas heater V include: 80-300°C, preferably 100-200°C.

[0093] According to a preferred embodiment of the present invention, the operating conditions of the raw material storage tank I include: 100-300°C.

[0094] According to a preferred embodiment of the present invention, the operating conditions of the heat exchanger II include: 100-500°C.

[0095] According to a preferred embodiment of the present invention, the operating conditions of the heater III include: 200-700°C.

[0096] According to a preferred embodiment of the present invention, the operating conditions of the load tower IV include: 200-800°C.

[0097] According to a preferred embodiment of the present invention, the operating conditions of the tail gas condenser VI include: a temperature of 40-70°C.

[0098] According to a preferred embodiment of the present invention, the operating conditions of the absorption tower VII include: 20-60°C.

[0099] According to a preferred embodiment of the present invention, the absorbent is one or more of acid, alkali and water.

[0100] According to a preferred embodiment of the present invention, the operating conditions of the gas condenser VIII include: 40-70°C.

[0101] According to a preferred embodiment of the present invention, the operating conditions of the gas subcooler IX include: -60°C to -30°C.

[0102] According to a preferred embodiment of the present invention, the operating conditions of the adsorption tower X include: dehydration of the adsorbent, the volume space velocity is preferably 1 to 5h -1 It is preferred to use two adsorption towers for switching operation, and switch to the other adsorption tower after one completes adsorption, and regenerate the adsorption tower that completes adsorption.

[0103] According to a preferred embodiment of the present invention, the operating conditions of the buffer tank XI include: -60°C to 40°C.

[0104] According to a preferred embodiment of the present invention, the operating conditions of the fan XII include: an outlet pressure of 0.03-0.3 MPag.

[0105] According to a preferred embodiment of the present invention, the loaded substance is a metal salt compound, and the boiling point is preferably 50-300°C.

[0106] According to a preferred embodiment of the present invention, the carrier gas 2 is an inert protective gas, preferably nitrogen.

[0107] According to a preferred embodiment of the present invention, the mass flow rate ratio of the gas-phase loaded substance to the loaded carrier gas 2 is 0.1-3.

[0108] According to a preferred embodiment of the present invention, preferably, the method further comprises: after completing the gas phase loading, using heated carrier gas to perform a roasting treatment on the carrier to complete the regeneration of the carrier.

[0109] The present invention provides application of the gas phase loading method or the gas phase loading system in catalyst preparation.

[0110] According to a preferred embodiment of the present invention, the raw material load gas is gasified and enters the gas heat exchanger together with the carrier gas for preheating. The flow rate of the load gas and the mass of the raw material storage tank jointly act on the flow rate of the heating medium to realize the outlet flow control of the load gas; the mixed gas is then heated to a certain temperature by the heater and then enters the load tower. The temperature rise of the load tower is controlled by controlling the power of the electric heater and the flow rate of the carrier gas. The exhaust gas is absorbed by the heat exchanger and the absorption tower in turn and then discharged in compliance with the standards. The washed exhaust gas is condensed in two stages and then the carrier gas is recovered after the adsorption tower.

[0111] According to one embodiment of the present invention, the present invention provides a system and method for gas-phase loading of a catalyst, the system mainly comprising:

[0112] (1) Load unit: mainly composed of raw material storage tank I, heat exchanger II, heater III, load tower IV, and carrier gas heater V; the gas phase at the top of the raw material storage tank is connected to the heat exchanger, the shell side of the heat exchanger is connected to the heater, the gas phase outlet of the heater is connected to the load tower, the load tower outlet is connected to the heat exchanger tube side, and the gas heater is connected to the gas phase outlet of the raw material storage tank and the gas phase inlet of the load tower respectively.

[0113] (2) Tail gas treatment unit: mainly composed of tail gas condenser VI and absorption tower VII; the gas outlet of the heat exchanger II tube is connected to the tail gas condenser, and the tail gas condenser enters the absorption tower.

[0114] (3) Gas recovery unit: It includes a gas condenser VIII, a gas subcooler IX, an adsorption tower X, a buffer tank XI, and a fan XII connected in series. The gas outlet of the absorption tower is connected to the gas condenser, the gas condenser outlet is connected to the gas subcooler, the gas subcooler outlet is connected to the adsorption tower, the adsorption tower outlet is connected to the buffer tank, and the buffer tank is connected to the fan.

[0115] According to a preferred embodiment of the present invention, the catalyst is loaded in a gas-phase manner, and an inert gas is used as a protective gas during the loading process. Preferably, the protective gas is nitrogen. The load and the protective gas enter the loading system according to proportional flow control, and the preferred mass flow rate ratio of the load and the protective gas is 0.1-3.

[0116] According to a preferred embodiment of the present invention, the support is preferably a metal salt compound, silicone oil, etc., and more preferably, the boiling point range is 50-300°C.

[0117] According to a preferred embodiment of the present invention, the raw material storage tank 1 is provided with a heating system, and the load is heated to a gas phase in the storage tank; preferably, the heating method adopts a coil or a jacket; the heating medium is preferably one of steam or thermal oil, and the thermal oil can be heated by electric heating to heat the load with a higher boiling point; more preferably, the outlet pipeline of the raw material storage tank 1 adopts heating, which can effectively prevent condensation of the gaseous load material.

[0118] According to a preferred embodiment of the present invention, the heat exchanger II is used to recover the heat of the tail gas after loading to preheat the loaded raw materials, thereby improving the utilization rate of heat. Preferably, a shell-and-tube heat exchanger is used, and the hot fluid flows through the tube side. After the loaded gas passes through the loading tower, some catalyst dust will be entrained. The tube side facilitates the cleaning of the heat exchanger. More preferably, the hot fluid enters from the top and exits from the bottom.

[0119] According to an embodiment of the present invention, a gas inlet and a catalyst loading port are provided at the top of the load tower IV, and the catalyst is loaded in a bag-shaped manner to reduce the breakage rate of the catalyst; preferably, the bottom is in an inverted cone shape, and a catalyst unloading port is provided, which is conducive to catalyst unloading; preferably, a gas outlet is provided next to the catalyst unloading port, and the gas outlet is filled with a wire mesh to prevent catalyst particles from being carried out by the gas; more preferably, the catalyst unloading port uses a flap-type flange cover, which is conducive to quick opening and closing and simple operation.

[0120] According to a preferred embodiment of the present invention, after the catalyst loading is completed, the carrier gas can be heated to a certain temperature to calcine the catalyst. This process can effectively reduce the transportation of the catalyst and reduce labor intensity.

[0121] According to a preferred embodiment of the present invention, the operating conditions of the above equipment are as follows:

[0122] (1) Heater III is used to reheat the load material, and the temperature after heating is preferably 200-700°C.

[0123] (2) The tail gas condenser is used to cool and recover the load. The temperature of the tail gas after condensation is preferably 40-70°C.

[0124] (3) The cooling temperature of the gas cooler is, for example, 40°C.

[0125] (4) The cooling temperature of the gas subcooler is -60 to -30°C.

[0126] (5) The adsorption tower uses a dehydrating adsorbent, and the volumetric air velocity is preferably 1 to 5 h -1 : It is preferred to switch the regeneration operation of the two adsorption towers.

[0127] (6) The blower should be a Roots blower or a compressor, and the outlet pressure should preferably be 0.1-0.3 MPag.

[0128] According to a preferred embodiment of the present invention, preferably, the absorption system is one or more of an acid absorption tower, an alkali absorption tower and a water absorption tower, thereby being able to effectively absorb the tail gas until it meets the emission standards.

[0129] According to a preferred embodiment of the present invention, by adding a gas cooler, a cryogenic refrigerator and an adsorption tower, the carrier gas can be recovered and reused to the greatest extent possible, effectively reducing the investment in the loading process.

[0130] According to a preferred embodiment of the present invention, the following control method is included:

[0131] Flow control of the load material; the outlet flow of the load material is controlled by the flow or temperature of the heating medium;

[0132] Load tower temperature control: The bed inlet temperature of the load tower is controlled by heater III, and the temperature rise of the load tower is controlled by the flow rate of the load gas and the concentration of the load substance.

[0133] According to a preferred embodiment of the present invention, the flow rate of the loaded material is controlled by the outlet flow rate and the mass of the raw material storage tank acting on the flow control valve (S.1) of the raw material heating medium. Through the joint control of flow rate and weight, the flow rate or total amount of the loaded gas can be controlled more accurately, avoiding insufficient load amount or excessive waste of loaded gas.

[0134] According to a preferred embodiment of the present invention, the load tower bed inlet temperature signal acts on the heater (S.2), the load tower bed temperature rise signal acts on the carrier gas flow control valve (S.3), and multiple temperature measuring points are set inside the bed. Preferably, the temperature signals are taken as one out of two, or two out of three...to prevent the local temperature rise from being too high and affecting the catalyst activity.

[0135] The raw material load gas is vaporized and enters the gas heat exchanger together with the carrier gas for preheating. The flow rate of the load gas and the mass of the raw material storage tank jointly act on the flow rate of the heating medium to realize the outlet flow control of the load gas; the mixed gas is then heated to a certain temperature by the heater and then enters the load tower. The temperature rise of the load tower is controlled by controlling the power of the electric heater and the flow rate of the carrier gas. The exhaust gas is absorbed by the heat exchanger and the absorption tower in turn and then meets the emission standards. The washed exhaust gas is condensed in two stages and then recycled into the adsorption tower to recover the carrier gas.

[0136] The following examples are all in accordance with Figure 1 The process shown is carried out.

[0137] Example 1

[0138] The catalyst carrier molecular sieve is loaded into the loading tower, and the air is preheated to a certain temperature by a gas heater to purge the catalyst bed. The air is then preheated to 450°C by carrier gas N2 to replace the catalyst bed and then cooled to room temperature.

[0139] The TiCl4 loading material is loaded into a raw material storage tank, using thermal oil as the heating medium. The power of the electric heater heating the thermal oil is controlled by the gas flow rate at the raw material storage tank outlet and the raw material storage tank quality, thereby achieving precise control of the raw material loading gas. The heated and vaporized loading gas is mixed with preheated N2 (mixing ratio 1:2) and heated to 150°C in a heat exchanger. It is then heated to 300°C by a heater before entering the catalyst bed to load the catalyst (operating at 300°C). The loading period is 6 hours, and the catalyst bed temperature is monitored in real time.

[0140] The loaded tail gas is then cooled to 45°C through a gas condenser after exchanging heat with the loaded raw material in the heat exchanger tube. The remaining loaded gas in the tail gas is condensed and collected for centralized treatment or reuse. The gas enters the alkali absorption tower (operating at 25°C). After passing through the tail gas absorption tower, the gas phase passes through a gas condenser (operating at 40°C), a gas subcooler (operating at -20°C), and an adsorption tower (adsorbent 5A molecular sieve, operating at -20°C) before being collected and reused.

[0141] Inert N2 gas heated to 400°C was introduced into the reactor to calcine the catalyst. The loaded and activated catalyst was then collected through a catalyst discharge port at the bottom of the reactor. The vapor-loaded catalyst exhibited excellent reaction activity. This is due to the fact that during the vapor deposition process, the active components were introduced as gas-phase molecules, resulting in a more uniform distribution on the support.

[0142] Example 2

[0143] The same as Example 1, except that the loading gas is mixed with preheated N2 (mixing ratio 1:3) to load the catalyst, and the loading time is 8 hours. The performance of the catalyst after loading is similar to that of Example 1. A larger amount of inert gas is mixed with the loading gas, and the catalyst bed temperature rise is more stable. However, at the same time, the loading time of the catalyst needs to be extended to achieve the same catalyst performance.

[0144] Example 3

[0145] The same as Example 1, except that the loaded gas was mixed with preheated N2 (mixing ratio 1:1) to load the catalyst, and the loading time was 4 hours. Through the study of the loading process and catalyst performance, it was found that when the concentration of the loaded gas in the loaded mixture was high, the initial temperature rise of the catalyst bed was faster, which was not conducive to the stable control of the catalyst performance, and the performance of the catalyst was slightly lower than that of Example 1.

[0146] Example 4

[0147] The same as Example 1, except that the loaded gas is water vapor. This is a water treatment process for the catalyst. Low-pressure steam can be used as the heating medium. After the catalyst bed is treated, inert gas N2 heated to 500°C is introduced into the reactor to calcine the catalyst. The moisture content of the catalyst after calcination is no more than 1wt%, and the catalyst is more convenient to unload.

[0148] Example 5

[0149] The operation method is the same as that of Example 1, except that attapulgite clay is used and the carrier gas is AlCl3. The operating conditions are as follows:

[0150] The heated and vaporized load gas is mixed with the preheated N2 (mixing ratio 1:2), heat-exchanged to 200°C in a heat exchanger, and then heated to 600°C by a heater before entering the catalyst bed to load the catalyst (operating condition 600°C). The loading time is 6 hours, and the catalyst bed temperature is monitored in real time.

[0151] The loaded tail gas is then cooled to 60°C through a gas condenser after exchanging heat with the loaded raw material in the heat exchanger tube. The remaining loaded gas in the tail gas is condensed and collected for centralized treatment or reuse. The gas enters the alkali absorption tower (operating at 40°C). After passing through the tail gas absorption tower, the gas phase passes through a gas condenser (operating at 50°C), a gas subcooler (operating at -50°C), and an adsorption tower (adsorbent 5A molecular sieve, operating at -50°C) before being collected and reused.

[0152] It should be noted that the embodiments described above are only used to explain the present invention and do not constitute any limitation of the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein. On the contrary, the present invention can be extended to all other methods and applications with the same function.

[0153] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A gas phase loaded system, characterized in that: The system includes: A load unit, comprising: A raw material storage tank (I), a heat exchanger (II), a heater (III), and a load tower (IV) are sequentially connected in series; and a carrier gas heater (V); The gas phase outlet of the raw material storage tank (I) is connected to the inlet of the heat exchanger (II), the outlet of the heat exchanger (II) is connected to the heater (III), the gas phase outlet of the heater (III) is connected to the gas phase inlet of the load tower (IV), the gas phase outlet of the load tower (IV) is connected to the inlet of the heat exchanger (II), and the carrier gas heater (V) is connected to the gas phase outlet of the raw material storage tank (I) and the inlet of the heat exchanger (II); Wherein, the raw material storage tank (I) is used to gasify the loaded material to obtain the gaseous loaded material; The carrier gas heater (V) is used to heat the load with the carrier gas and mix it with the gas-phase load material to enter the heat exchanger (II) for the first heat exchange, then enter the heater (III) for the second heating, and then enter the load tower (IV) to contact with the carrier for gas-phase loading; the load tail gas flows out through the gas phase outlet of the load tower (IV) and passes through the heat exchanger (II) for the first heat exchange.

2. The system according to claim 1, wherein: The system also includes: A tail gas treatment unit, the tail gas treatment unit comprising a tail gas condenser (VI) and an absorption tower (VII) connected in series; the inlet of the tail gas condenser (VI) is connected to the outlet of the heat exchanger (II); the outlet of the tail gas condenser (VI) is connected to the inlet of the absorption tower (VII); The loaded tail gas flows out from the gas phase outlet of the loading tower (IV), undergoes the first heat exchange through the heat exchanger (II), enters the tail gas condenser (VI) for condensation, and then enters the absorption tower (VII) for contact and absorption with the absorbent.

3. The system according to claim 1, wherein: The system also includes: A gas recovery unit, comprising: a gas condenser (VIII), a gas supercooler (IX), an adsorption tower (X), a buffer tank (XI), and a fan (XII) connected in series; The gas outlet of the absorption tower (VII) is connected to the inlet of the gas condenser (VIII), the outlet of the gas condenser (VIII) is connected to the inlet of the gas supercooler (IX), the outlet of the gas supercooler (IX) is connected to the inlet of the adsorption tower (X), the outlet of the adsorption tower (X) is connected to the inlet of the buffer tank (XI), the buffer tank (XI) is connected to the fan (XII), and the buffer tank (XI) is pressurized by the fan (XII).

4. The system according to claim 3, wherein: The loading tower (IV) is provided with a gas inlet and a carrier loading port at the top; the bottom is provided with an inverted cone shape, a catalyst unloading port is provided at the bottom, and a gas outlet is provided on the side; and / or The raw material storage tank (I) is provided with a top gas phase outlet, and the raw material storage tank (I) is configured to be self-heating, and the loaded material is heated to a gas phase in the raw material storage tank (I); and / or Heat exchanger (II) is set as heat flow tube pass; and / or The absorption tower includes one or more of an acid absorption tower, an alkali absorption tower, and a water absorption tower; and / or The absorption tower (VII) is provided with a side wall inlet, a top outlet and a bottom outlet; and / or The adsorption tower (X) is provided with a bottom inlet and a top outlet; and / or The buffer tank (XI) is provided with a top inlet.

5. The system according to claim 4, wherein: The catalyst discharge port uses a flap-type flange cover, and the side gas outlet is filled with wire mesh; and / or The self-heating method adopts coils or jackets; the heating medium is steam and / or heat conduction; the outlet pipeline of the raw material storage tank (I) adopts insulation or heating; and / or The carrier gas heater (V) is connected to the shell side inlet of the heat exchanger (II), the gas phase outlet of the raw material storage tank (I) is connected to the shell side inlet of the heat exchanger (II), the gas phase outlet of the load tower (IV) is connected to the tube side inlet of the heat exchanger (II); the shell side outlet of the heat exchanger (II) is connected to the heater (III); and / or The heat exchanger (II) is a shell and tube heat exchanger.

6. A gas phase loading method, characterized in that: The method is carried out in the system according to any one of claims 1 to 5.

7. The method according to claim 6, wherein: The method includes: The carrier gas heater (V) heats the carrier gas and mixes it with the gaseous loaded material from the raw material storage tank (I) before entering the heat exchanger (II) for a first heat exchange. The gas then enters the heater (III) for a second heating and enters the loading tower (IV) to contact the carrier for gaseous loading. The loaded tail gas flows out of the gaseous phase outlet of the loading tower (IV), exchanges heat in the heat exchanger (II), and is then sent to the tail gas treatment unit. After condensation in the tail gas condenser (VI), it enters the absorption tower (VII) and is contacted with the absorbent for absorption; The absorption tail gas discharged from the absorption tower (VII) enters the gas condenser (VIII) for the first condensation, then enters the gas supercooler (IX) for the first cooling, and then enters the adsorption tower (X) for adsorption. The gas discharged from the adsorption tower (X) enters the buffer tank (XI) and is pressurized and recovered by the fan to obtain the recovered carrier gas. The fan (XII) pressurizes the buffer tank (XI).

8. The method according to claim 7, wherein: The operating conditions of the carrier gas heater (V) include: 80-300°C; and / or The operating conditions of the raw material storage tank (I) include: 100-300°C; and / or The operating conditions of the heat exchanger (II) include: 100-500°C; and / or The operating conditions of heater (III) include: 200-700°C; and / or The operating conditions of the load tower (IV) include: 200-800°C; and / or The operating conditions of the tail gas condenser (VI) include: temperature of 40-70°C; and / or The operating conditions of the absorption column (VII) include: 20-60°C; and / or The absorbent is one or more of acid, alkali and water; and / or The operating conditions of the gas condenser (VIII) include: 40-70°C; and / or The operating conditions of the gas subcooler (IX) include: -60°C to -30°C; and / or The operating conditions of the adsorption tower (X) include: volume space velocity of 1 to 5 h -1 ; Use two adsorption towers for switching operation. After one adsorption tower completes adsorption, it switches to the other adsorption tower, and the adsorption tower that completes adsorption is regenerated; and / or The operating conditions of the buffer tank (XI) include: -60°C to 40°C; and / or The operating conditions of the fan (XII) include: outlet pressure of 0.03-0.3 MPag; and / or The loaded substance is a metal salt compound; and / or The carrier gas (2) used for loading is an inert protective gas; and / or The mass flow rate ratio of the gas phase loaded substance to the loading carrier gas (2) is 0.1-3.

9. The method according to claim 8, wherein The operating conditions of the carrier gas heater (V) include: 100-200°C; and / or The boiling point of metal salt compounds is 50-300°C; and / or The carrier gas (2) used for loading is nitrogen; and / or The method further includes: After the gas phase loading is completed, the carrier is calcined using heated carrier gas to complete the carrier regeneration.

10. Use of the gas-phase loading method according to any one of claims 6 to 9 or the gas-phase loading system according to any one of claims 1 to 5 in catalyst preparation.

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