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Process design for gas separation membranes: Gas separation membranes are generally made of organic polymer materials, which presents problems related to strength, chemical erosion, and mechanical scouring. Strength issues include the absolute pressure that the membrane can withstand as well as the pressure difference it can handle. Due to the special properties of membrane structures, strength issues also involve the problem of preventing backpressure, meaning that the pressure on the high-pressure side of the membrane must always be greater than or equal to that on the low-pressure side. To prevent the membrane from being chemically corroded, it is essential to pre-treat the gas entering the membrane by removing those substances that are harmful to it, or by controlling their concentration. High-speed mechanical erosion, especially by gases containing mechanical particles, can cause damage to the membrane surface and reduce its service life. Therefore, reducing the gas flow rate and removing the mechanical particles from the gas is crucial for extending the membrane’s lifespan. Extensive practical experience has shown that when the flow rate within the membrane module is less than 1.5–2 meters per second, mechanical erosion by the gas does not cause any damage to the membrane surface. The gas membrane separation process generally consists of two units, namely the pretreatment unit and the membrane separation unit. The task of the pretreatment unit is to prevent the membranes from being chemically degraded, thereby extending their service life and ensuring the long-term stable operation of the gas membrane separation process. The membrane separation unit is the core of the gas membrane separation process; the separation of different gases takes place within this unit. The main challenge it must address is how to optimize the combination of membrane modules, as well as the patterns and methods of gas flow, under the existing total pressure difference, in order to meet the separation requirements while using the minimum possible number of membrane modules and thus achieving the most economical equipment investment. A successful membrane separation process design must be a perfect combination of the pretreatment unit and the membrane separation unit. Since pressure is an important factor in the gas separation process, reducing the system pressure drop is crucial for process design and piping design. This is especially true for low-pressure membrane separation processes, where a pressure drop of 0.1–0.2 MPa can have a significant negative impact on the separation efficiency. When designing gas membrane separation processes, safety issues must be taken into consideration, which have two aspects: equipment safety and personnel safety. In terms of equipment safety, damage to membrane modules often results in significant economic losses for manufacturers; therefore, sufficient attention must be paid to this issue during process design, so that the membranes remain under proper protection throughout the startup, operation, and shutdown phases of the system. At the same time, overpressure damage to the equipment, as well as severe local leaks of gas, can pose a direct or indirect threat to the safety of personnel; these issues should also be given due attention during process design. Precautions for membrane separation devices: 1. The system pressure should be increased slowly, especially in the case of the membrane separation unit; this is necessary to prevent damage to the membrane surface caused by excessive gas flow velocity within the membrane modules. 2. When the pretreatment unit has not yet been started up or has not reached stability, gas must not be allowed to enter the membrane, to prevent oil contamination in the gas from damaging the membrane; it may also cause the membrane to experience excessive temperature or pressure. 3. During the operation of the system, sufficient attention should be paid to the liquid level in the cyclone separator as well as the pressure difference across the high-efficiency filter; regular drainage of these devices on site is necessary. 4. The system must not accumulate pressure; ensure that all exhaust outlets remain unobstructed. 5. After a long period of parking, be sure to close the root valve in front of the control valve. 6. When draining the system, it is essential to prevent excessive pressure differences across the membrane as well as backpressure from occurring. 7. Regularly inspect the instrumentation system to ensure that the instruments are operating in good condition. 8. Prevent the occurrence of exhaust gas condensation.