Hydrogen purification and recovery device for BDO hydrogenation degassing and use method of hydrogen purification and recovery device

Abstract

A hydrogen purification and recovery device for BDO hydrogenation degassing comprises a gas-liquid separation tank, an activated carbon storage tank, a purifying agent storage tank and a desorbed gas mixing tank. According to the hydrogen purification and recovery device for BDO hydrogenation degassing and the using method thereof, a BDO hydrogenation tail gas exhaust port is connected with a gas-liquid separation tank through a pipeline, then the BDO hydrogenation tail gas sequentially passes through an activated carbon filter and an air purifier, and the content of nickel carbonyl in the tail gas finally discharged is smaller than or equal to 0.05 ppm; the hydrogen tail gas and the desorbed gas passing through the air purifier are pressurized to 3.0 Mpa through a desorbed gas mixing tank and a desorbed gas compressor in sequence, and are finally conveyed to the methanol synthesis device for recycling; the adsorption box is additionally arranged in the recovery device, so that the adsorption and purification effect of hydrogen impurities can be further improved, and the problems of hydrogen tail gas recovery and removal of nickel carbonyl contained in the hydrogen tail gas are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of BDO processing equipment, and in particular relates to a hydrogen purification and recovery device for BDO hydrogenation exhaust and a use method thereof. Background Art

[0002] The BDO device uses calcium carbide, methanol and hydrogen as the main raw materials and adopts the improved Reppe process. The hydrogenation process in the Reppe process of producing BDO adopts low-pressure and high-pressure two-step hydrogenation technology, involving a low-pressure hydrogenation reactor, a high-pressure hydrogenation reactor and its ancillary equipment. The BYD raw material generated by the acetylene-aldehyde reaction first enters the low-pressure reactor and undergoes a hydrogenation reaction under the action of a Raney nickel catalyst. In this step, most of the BYD is converted into BDO; then the low-pressure hydrogenated material enters the high-pressure hydrogenation reactor and undergoes a secondary hydrogenation reaction under the action of a nickel-based high-pressure hydrogenation catalyst. The reaction conversion rate of this step can reach more than 95%, and the obtained BDO aqueous solution is sent to the tank area to wait for entering the distillation system.

[0003] A large amount of exhaust gas is generated during the hydrogenation process, which is usually introduced into a flare for combustion. However, the exhaust gas contains more than 90% hydrogen. Simple combustion causes serious waste of hydrogen and increases the production cost of the enterprise.

[0004] Since Raney nickel catalyst is used in the low-pressure hydrogenation process, it is found that there is excessive Ni(CO)4 in the exhaust gas during the actual production process, which indicates that the catalyst generates carbonyl nickel during use. Studies have shown that the effect of Ni(CO)4 on methanol synthesis catalyst is the result of the gradual deposition and accumulation of nickel in the synthesis gas on the catalyst, that is, the deposition effect. Although nickel deposition only causes a loss of 0.1% of the BET specific surface area of ​​the catalyst, the loss of catalyst activity is much greater than the activity loss caused by the loss of 0.1% specific surface area. This may be due to the fact that the active center of methanol synthesis on the catalyst is in the same position as the active center of the catalyst for decomposing carbonyl metals. In addition, the presence of carbonyl nickel will affect the quality of methanol products. Since nickel is the active component of the Fischer-Tropsch reaction, the presence of carbonyl nickel will lead to the generation of many side reactions, such as the generation of hydrocarbons, ethers and paraffin, causing reactor blockage, increasing the impurity content in crude methanol, affecting the chromaticity of methanol products, and bringing great difficulties to the separation process. Therefore, the presence of carbonyl nickel will cause irreversible damage to the use and operation of methanol synthesis catalysts. How to remove carbonyl nickel in hydrogen tail gas is the biggest problem in the process of hydrogen recovery and utilization. Summary of the invention

[0005] The invention provides a hydrogen purification and recovery device for BDO hydrogenation exhaust and a method for using the same. The BDO hydrogenation tail gas outlet is connected to a gas-liquid separation tank through a pipeline, and then passes through an activated carbon filter and an air purifier in sequence, and the carbonyl nickel content in the tail gas finally discharged is ≤0.05ppm; the hydrogen tail gas and the desorption gas passing through the air purifier are pressurized to 3.0Mpa through a desorption gas mixing tank and a desorption gas compressor in sequence, and finally sent to a methanol synthesis device for recycling; an adsorption box is added to the recovery device, which can further increase the adsorption and purification effect of hydrogen impurities, and solve the problem of hydrogen tail gas recovery and removal of the carbonyl nickel contained therein.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: The hydrogen purification and recovery device for BDO hydrogenation exhaust is characterized by comprising a gas-liquid separation tank, an activated carbon storage tank, a purifier storage tank and an analytical gas mixing tank; the BDO hydrogenation tail gas outlet is connected to the gas-liquid separation tank through a pipeline, the gas-liquid separation tank is connected to the activated carbon storage tank through a pipeline, the activated carbon storage tank is connected to the purifier storage tank through a pipeline, the purifier storage tank is connected to the analytical gas mixing tank through a pipeline, and the analytical gas mixing tank is connected to the methanol synthesis device through a pipeline; An adsorption box is also provided between the purifier storage tank and the gas analysis mixing tank: the adsorption box has a rectangular shape, a vibration motor is provided at the bottom of the adsorption box, a flow guide channel is provided inside the adsorption box through a partition, and an adsorption mechanism is provided between the flow guide channels; the adsorption mechanism includes a storage box, an adsorption plate and a collection box, a discharge pipe is provided at the bottom of the storage box, a feed pipe is provided at the top of the collection box, and the adsorption plate is obliquely arranged between the discharge pipe and the feed pipe; the adsorption plate is provided with a main flow channel, a branch flow channel and a vent, and the branch flow channel is located between the main flow channels; The appearance and structure of the discharge pipe and the feed pipe are the same. A spiral conveying shaft is arranged in the discharge pipe. The spiral conveying shaft is installed in the discharge pipe through a plurality of tension springs. A sharp needle arranged upward is arranged on the top of the spiral conveying shaft.

[0007] An air purifier is arranged between the adsorption box and the analytical gas mixing tank.

[0008] A desorption gas compressor is provided between the desorption gas mixing tank and the methanol synthesis device.

[0009] The gas-liquid separation tank is provided with an auxiliary pipeline connected to the torch.

[0010] The BDO hydrogenation tail gas outlet is connected to a flare through a pipeline.

[0011] A low-pressure hydrogenation reactor is also provided on the pipeline between the BDO hydrogenation tail gas outlet and the gas-liquid separation tank.

[0012] The method for using the hydrogen purification and recovery device for BDO hydrogenation exhaust gas comprises the following steps: A. The BDO hydrogenation tail gas outlet is connected to the gas-liquid separation tank through a pipeline, and then passes through the activated carbon storage tank, the purifier storage tank, the air purifier and the adsorption box in sequence. The carbonyl nickel content in the tail gas is ≤0.05ppm; B. The hydrogen tail gas and the analytical gas that have passed through the air purifier are pressurized to 3.0Mpa through the analytical gas mixing tank and the analytical gas compressor in turn, and finally sent to the methanol synthesis unit for recycling; C. Hydrogen tail gas can be directly transported to the flare through the BDO hydrogenation tail gas outlet.

[0013] The hydrogen tail gas can be transported to the gas-liquid separation tank through the BDO hydrogenation tail gas outlet, and the hydrogen is directly transported to the flare after separation in the gas-liquid separation tank.

[0014] Beneficial Effects By adopting the above technical solution, the beneficial effects of the present invention are: The hydrogen purification and recovery device for BDO hydrogenation exhaust provided by the present invention and the use method thereof are expected to reduce the content of carbonyl nickel in the hydrogen tail gas to below 0.05 ppm, which can solve the problem of the presence of carbonyl nickel components in the hydrogen tail gas, eliminate possible factors affecting the use and operation of the methanol synthesis catalyst, and ultimately achieve high utilization of hydrogen raw materials; An adsorption box is added to the recovery device. When the adsorption box is running, the vibration motor is started first. The action of the vibration motor drives the spiral conveying shaft in the discharge pipe to vibrate up and down. The spiked needle on the top of the spiral conveying shaft contacts the adsorbent in the storage box and makes it fall into the discharge pipe. The adsorbent slowly moves downward along the spiral conveying shaft to the main flow channel of the adsorption plate. From the main flow channel to the branch flow channel, the adsorbent slowly slides downward due to the vibration of the vibration motor. When hydrogen passes through the air holes of the adsorption plate, it contacts the adsorbent. The main impurity carbonyl nickel contained in the hydrogen is adsorbed by the adsorbent. The hydrogen slowly passes through the adsorption box, and the impurities in the hydrogen are absorbed by the slowly moving adsorbent. The adsorbent that absorbs the impurities enters the collection box through the feed pipe, which can further increase the adsorption and purification effect of the hydrogen impurities.

[0015] The device is compact in design and can be directly modified and installed on existing equipment, which reduces equipment modification costs, avoids waste of raw materials, and improves production efficiency.

[0016] The invention provides a hydrogen purification and recovery device for BDO hydrogenation exhaust and a method for using the same. The BDO hydrogenation tail gas outlet is connected to a gas-liquid separation tank through a pipeline, and then passes through an activated carbon filter and an air purifier in sequence, and the carbonyl nickel content in the tail gas finally discharged is ≤0.05ppm; the hydrogen tail gas and the desorption gas passing through the air purifier are pressurized to 3.0Mpa through a desorption gas mixing tank and a desorption gas compressor in sequence, and finally sent to a methanol synthesis device for recycling, thereby solving the problem of hydrogen tail gas recovery and removal of the carbonyl nickel contained therein. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 It is a structural schematic diagram of the adsorption box in the present invention; Figure 3 It is a schematic diagram of the internal structure of the adsorption box in the present invention; Figure 4 It is a structural schematic diagram of the adsorption plate in the present invention; Figure 5 It is a schematic diagram of the structure of the discharge pipe in the present invention.

[0018] Gas-liquid separation tank 1, activated carbon storage tank 2, purifier storage tank 3, analytical gas mixing tank 4, BDO hydrogenation tail gas outlet 5, methanol synthesis unit 6, air purifier 7, analytical gas compressor 8, torch 9, low-pressure hydrogenation reactor 10, adsorption box 11, vibration motor 12, partition 13, storage box 14, adsorption plate 15, collection box 16, discharge pipe 17, feed pipe 18, screw conveyor shaft 19, tension spring 20, spike needle 21, main flow channel 22, branch flow channel 23, vent 24. DETAILED DESCRIPTION

[0019] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0020] The following will be combined with the drawings in the embodiments of the invention to clearly and completely describe the technical solutions in the embodiments of the invention. Obviously, the described embodiments are only part of the embodiments of the invention, not all of the embodiments. Based on the embodiments of the invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the invention.

[0021] like Figure 1-Figure 5 As shown, the hydrogen purification and recovery device for BDO hydrogenation exhaust gas includes a gas-liquid separation tank 1, an activated carbon storage tank 2, a purifier storage tank 3 and a decomposition gas mixing tank 4; the BDO hydrogenation tail gas outlet 5 is connected to the gas-liquid separation tank 1 through a pipeline, the gas-liquid separation tank 1 is connected to the activated carbon storage tank 2 through a pipeline, the activated carbon storage tank 2 is connected to the purifier storage tank 3 through a pipeline, the purifier storage tank 3 is connected to the decomposition gas mixing tank 4 through a pipeline, and the decomposition gas mixing tank 4 is connected to the methanol synthesis device 6 through a pipeline.

[0022] An adsorption box 11 is also provided between the purifier storage tank 3 and the gas analysis mixing tank 4: the adsorption box 11 has a rectangular shape, a vibration motor 12 is provided at the bottom of the adsorption box 11, a flow guide channel is provided inside the adsorption box 11 through a partition 13, and an adsorption mechanism is provided between the flow guide channels; the adsorption mechanism includes a storage box 14, an adsorption plate 15 and a collection box 16, a discharge pipe 17 is provided at the bottom of the storage box 14, a feed pipe 18 is provided at the top of the collection box 16, and the adsorption plate 15 is tilted between the discharge pipe 17 and the feed pipe 18; the adsorption plate 15 is provided with a main channel 22, a branch channel 23 and a vent 24, and the branch channel 23 is located between the main channel 22; the storage box 14 and the collection box 16 are both provided with material inlets and outlets. The adsorbents in the storage box 14 and the collection box 16 can be replaced with different adsorbents according to the requirements of the adsorption operation to achieve different adsorption effects.

[0023] The discharge pipe 17 and the feed pipe 18 have the same external structure. A screw conveying shaft 19 is provided in the discharge pipe 17 . The screw conveying shaft 19 is installed in the discharge pipe 17 through a plurality of tension springs 20 . A spike needle 21 is provided on the top of the screw conveying shaft 19 .

[0024] An air purifier 7 is provided between the adsorption box 11 and the analytical gas mixing tank 4 .

[0025] A desorption gas compressor 8 is provided between the desorption gas mixing tank 4 and the methanol synthesis device 6 .

[0026] An auxiliary pipeline connected to the flare 9 is provided on the gas-liquid separation tank 1 .

[0027] The BDO hydrogenation tail gas outlet 5 is connected to the flare 9 through a pipeline.

[0028] A low-pressure hydrogenation reactor 10 is also provided on the pipeline between the BDO hydrogenation tail gas outlet 5 and the gas-liquid separation tank 1 .

[0029] The method for using the hydrogen purification and recovery device for BDO hydrogenation exhaust gas comprises the following steps: A. The BDO hydrogenation tail gas outlet 5 is connected to the gas-liquid separation tank 1 through a pipeline, and then passes through the activated carbon storage tank 2, the purifier storage tank 3, the air purifier 7 and the adsorption box 11 in sequence, and the carbonyl nickel content in the tail gas finally discharged is ≤0.05ppm; B. The hydrogen tail gas and the analytical gas after passing through the air purifier 7 are pressurized to 3.0 MPa through the analytical gas mixing tank 4 and the analytical gas compressor 8 in turn, and finally sent to the methanol synthesis device 6 for recycling; C. Hydrogen tail gas can be directly transported to the flare 9 through the BDO hydrogenation tail gas outlet 5.

[0030] The hydrogen tail gas can be transported to the gas-liquid separation tank 1 through the BDO hydrogenation tail gas outlet 5 , and the hydrogen is directly transported to the flare 9 after separation in the gas-liquid separation tank 1 .

[0031] (1) The relevant parameters of hydrogen tail gas in the hydrogenation section are as follows: According to the current equipment operating load and in preparation for future load increase, the total air intake volume is set at 600-1000Nm3 / h; the tail gas composition is shown in Table 1; the operating parameters of the low-pressure hydrogenation reactor 10 are temperature 55-65°C and pressure 2.0MPa (G).

[0032] Table 1 Exhaust gas composition (2) According to the relevant parameters of tail gas, the main research and development contents are as follows: Design and develop the main purification equipment including gas-liquid separator, activated carbon filter and air purification filter, and connect them with the low-pressure hydrogenation reactor 10, analytical gas mixing tank 4, analytical gas compressor 8 and methanol synthesis unit 6. The gas-liquid separation tank 1, activated carbon storage tank 2 and air purifier 7 are fixedly connected with the existing PSA device. The gas-liquid separation tank 1 is fixedly installed with a liquid level gauge root valve. The liquid level gauge root valve is set to facilitate real-time monitoring of the liquid level after separation in the gas-liquid separator, avoiding the phenomenon of excessive liquid level.

[0033] The inlet and outlet valves of the low-pressure hydrogenation reactor 10, the gas-liquid separation tank 1, the activated carbon storage tank 2, the air purifier 7, the analytical gas mixing tank 4, the analytical gas compressor 8 and the methanol synthesis device 6 are fixedly connected in sequence. The low-pressure hydrogenation reactor 10 is a very important equipment in the organic chemistry laboratory and the actual production process. It can not only be used as a container for hydrogenation reaction, but also can be used in occasions where liquid and gas (exhaust gas) need to be fully mixed. The gas-liquid separation tank 1 filters out the liquid in the exhaust gas exhausted from the low-pressure hydrogenation reactor 10. After the filtration, the gas continues to pass through the activated carbon storage tank 2 and the air purifier 7 for further filtration, and then is purified by adsorption through the adsorption box 11. Since the adsorbent of the adsorption box 11 is moved and updated in real time, the hydrogen is always in contact with the latest adsorbent when passing through the adsorption plate 15, ensuring that the adsorbent is in the best state for adsorbing impurities.

[0034] Operation and benefit status after implementation: Based on the exhaust gas of 700 Nm³ per hour and the hydrogen cost of 1.1 yuan / Nm³, the amount of hydrogen that can be recovered and discharged per hour can reach 770 yuan. Based on 8,000 hours per year, the annual benefit exceeds 6.16 million yuan.

[0035] The present invention provides a hydrogen purification and recovery device for BDO hydrogenation exhaust and a method for using the same. The BDO hydrogenation tail gas outlet 5 is connected to a gas-liquid separation tank 1 through a pipeline, and then passes through an activated carbon storage tank 2 and an air purifier 7 in sequence, and the carbonyl nickel content in the tail gas finally discharged is ≤0.05ppm; the hydrogen tail gas and the desorption gas passing through the air purifier 7 are pressurized to 3.0Mpa through a desorption gas mixing tank 4 and a desorption gas compressor 8 in sequence, and finally sent to a methanol synthesis device 6 for recycling, thereby solving the problem of hydrogen tail gas recovery and removal of the carbonyl nickel contained therein.

[0036] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. Hydrogen purification and recovery device for BDO hydrogenation exhaust, characterized by: It includes a gas-liquid separation tank, an activated carbon storage tank, a purifier storage tank and an analytical gas mixing tank; the BDO hydrogenation tail gas outlet is connected to the gas-liquid separation tank through a pipeline, the gas-liquid separation tank is connected to the activated carbon storage tank through a pipeline, the activated carbon storage tank is connected to the purifier storage tank through a pipeline, the purifier storage tank is connected to the analytical gas mixing tank through a pipeline, and the analytical gas mixing tank is connected to the methanol synthesis device through a pipeline; An adsorption box is also provided between the purifier storage tank and the gas analysis mixing tank: the adsorption box has a rectangular shape, a vibration motor is provided at the bottom of the adsorption box, a flow guide channel is provided inside the adsorption box through a partition, and an adsorption mechanism is provided between the flow guide channels; the adsorption mechanism includes a storage box, an adsorption plate and a collection box, a discharge pipe is provided at the bottom of the storage box, a feed pipe is provided at the top of the collection box, and the adsorption plate is obliquely arranged between the discharge pipe and the feed pipe; the adsorption plate is provided with a main flow channel, a branch flow channel and a vent, and the branch flow channel is located between the main flow channels; The appearance and structure of the discharge pipe and the feed pipe are the same. A spiral conveying shaft is arranged in the discharge pipe. The spiral conveying shaft is installed in the discharge pipe through a plurality of tension springs. A sharp needle arranged upward is arranged on the top of the spiral conveying shaft.

2. The hydrogen purification and recovery device for BDO hydrogenation exhaust gas according to claim 1, characterized in that: An air purifier is arranged between the adsorption box and the analytical gas mixing tank.

3. The hydrogen purification and recovery device for BDO hydrogenation exhaust gas according to claim 2, characterized in that: A desorption gas compressor is provided between the desorption gas mixing tank and the methanol synthesis device.

4. The hydrogen purification and recovery device for BDO hydrogenation exhaust gas according to claim 3, characterized in that: The gas-liquid separation tank is provided with an auxiliary pipeline connected to the torch.

5. The hydrogen purification and recovery device for BDO hydrogenation exhaust gas according to claim 4, characterized in that: The BDO hydrogenation tail gas outlet is connected to a flare through a pipeline.

6. The hydrogen purification and recovery device for BDO hydrogenation exhaust gas according to claim 5, characterized in that: A low-pressure hydrogenation reactor is also provided on the pipeline between the BDO hydrogenation tail gas outlet and the gas-liquid separation tank.

7. The method for using the hydrogen purification and recovery device for BDO hydrogenation exhaust gas according to claim 1, characterized in that: The following steps are involved: A. The BDO hydrogenation tail gas outlet is connected to the gas-liquid separation tank through a pipeline, and then passes through the activated carbon storage tank, the purifier storage tank, the air purifier and the adsorption box in sequence. The carbonyl nickel content in the tail gas is ≤0.05ppm; B. The hydrogen tail gas and the analytical gas that have passed through the air purifier are pressurized to 3.0Mpa through the analytical gas mixing tank and the analytical gas compressor in turn, and finally sent to the methanol synthesis unit for recycling; C. Hydrogen tail gas can be directly transported to the flare through the BDO hydrogenation tail gas outlet.

8. The method for using the hydrogen purification and recovery device for BDO hydrogenation exhaust gas according to claim 7, characterized in that: The hydrogen tail gas can be transported to the gas-liquid separation tank through the BDO hydrogenation tail gas outlet, and the hydrogen is directly transported to the flare after separation in the gas-liquid separation tank.

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