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This post was last edited by QQ Never give up on 11/9/2011 at 12:51. What are the key operating points for initially starting up a pressure swing adsorption carbon removal unit? (1) Conduct a comprehensive inspection and acceptance of the system’s equipment, management systems, automatic control systems, instruments at various control points, and electrical facilities, in accordance with the installation drawings and plans. (2) Conduct hydraulic strength tests, hydraulic tightness tests, purging or cleaning, pneumatic tightness tests, leakage rate tests, and vacuum degree tests on the equipment and piping systems in accordance with the setup requirements and relevant regulations, and verify that they meet the specified standards. (3) Calibrate the on-site pressure gauges and thermometers as required; within their measurement range, the accuracy shall not be lower than grade 1.5. (4) Calibrate the pressure transmitter as required; within its range, the measurement accuracy shall not be lower than grade 1.5. Apply a current of 4–20 mA to check whether the zero and full-scale values are correct. For pressure transmitters operating under negative pressure conditions, in addition to positive pressure calibration, accurate vacuum level calibration is also necessary; within the measurement range, the accuracy must be no less than Class 1.5. (5) The CO2 online analyzer was calibrated using a standard gas and passed the inspection. (6) The flow meter shall be calibrated and adjusted in accordance with the requirements of the instruction manual, and the relevant coefficient of the flow meter shall be determined. (7) Check the crisis oil pressure control system. In accordance with the requirements and procedures specified in the instruction manual, carefully check whether there are any errors in the wiring of the solenoid valve, and dynamically verify whether the operation of the programmable valve meets the design specifications. Ensure that all functions of the control system are operating properly, and that the alarm functions meet the design requirements. (8) Electrical interlock test for the vacuum pump and oil pump in the purification and refinement system. In accordance with the requirements of the operating instructions, carry out the electrical interlock tests for the vacuum pump and oil pump of the purification system, the electrical interlock tests for the vacuum pump and oil pump of the purification system, and the interlock tests for the water supply system of the vacuum pump, following the prescribed procedure. During the test, repeated observations are required until the design requirements are met. (9) Performance tests of the vacuum pump in the purification and cleaning equipment, as well as internal leakage tests of the check valve. The vacuum pump performance test and the check valve internal leakage test are carried out after the tests on the hydraulic pipeline system, the process pipeline system, and the calibration of instruments and control systems are completed. This task includes the following four items: ① Vacuum pump ultimate vacuum test ； ② Vacuum pump pumping capacity test ； ③ Check valve internal leakage test ； ④ Conduct individual testing on equipment such as vacuum pumps, etc. During the above work, it is necessary to strictly follow the instructions and the technical requirements of the equipment manufacturer to ensure that the tests are successful. (10) Fill the adsorption tower with adsorbent in accordance with the requirements of the \"Adsorbent Filling Notice\". (11) Joint trial operation. The hydraulic system and the control system are linked according to the operation timing diagram of the programmable valve, with a cycle time of 3 to 5 minutes, in order to thoroughly remove impurities from the hydraulic system and the cylinders of the programmable valve, until no bubbling occurs within the entire system over a period of 72 hours. (12) Follow the normal startup procedure; once the system has been properly replaced, start up by feeding materials in. What are the main types of pressure swing adsorption carbon removal units? 5 _* A& a1 b* q8 z Depending on their application, pressure swing adsorption carbon removal units can be divided into three types: units that remove carbon dioxide solely to produce purified gas ； Device for removing carbon dioxide from syngas and producing food-grade liquid carbon dioxide as a by-product ； A device for simultaneously producing decarburized purified gas and carbon dioxide gas with a purity of 98%. 2 @/ a7 t+ i$ B6 U2 h（1）PSA decarburization unit: At present, the most commonly used units in small and medium-sized ammonia synthesis plants are still PSA units that simply remove CO2 to produce purified gas, as an alternative to traditional wet decarburization methods. Depending on the various requirements of ammonia plants, there are two processes: one is a decarburization process aimed at replacing carbonization to increase the production of liquid ammonia. After PSA decarburization of the transformed gas, the CO2 content in the purified gas is less than 0.2%, allowing it to proceed directly to the refining process. Currently, the performance of such devices is as follows: the hydrogen recovery rate is >97%, the hydrogen-to-nitrogen ratio in the purified gas is around 3.0, and while removing CO2, it also eliminates most impurities such as CH4, CO, and H2S, thereby reducing the burden on subsequent processing stages. Another type is used for processes that work in conjunction with glycol plants. Since the purified gas is used in the production of diol, and considering the lifespan of the methanol synthesis catalyst as well as the need to maximize CO recovery, the CO2 content in the decarburized purified gas is generally kept at 1% to 5%. Currently, the performance of such devices shows a hydrogen recovery rate of >98% and a CO recovery rate of >90%. While removing CO2, the sulfides in the transformed gas are also reduced to a level of 0.1 mg/m3 (standard), and trace impurities such as chlorine, ammonia, water, and arsenic present in the feed gas can be removed simultaneously. + o& }. A, z9 f4 w3 A* l0 ~ (2) Decarburization unit for co-producing liquid CO2: The off-gas from the PSA decarburization unit is fed into a compressor at atmospheric pressure; after being pressurized to a certain level, it undergoes preprocessing to remove various sulfides, trace amounts of arsenic, fluorine, chlorine, and saturated water present in the off-gas, so as to meet the requirements for food-grade CO2. The pre-treated gas is cooled below 0°C to turn the CO2 in the desorbed gas into a liquid, which then enters a purification tower where CO2 is separated from other gases. Finally, a food-grade liquid CO2 product with a purity of 99.5% to 99.999% is obtained at the bottom of the purification tower. 4 O; Y' }" d& J# b2 y(3) A device for decarburization and simultaneous production of pure CO2, which consists of a purification system and a cleaning system; both systems employ a multi-tower PSA process. The transformed gas passes through a purification system to concentrate the CO2 concentration to over 98.5%, for use in the urea plant. The intermediate gas from the purification system enters the purification unit, where CO2 in this gas is further reduced to levels below 0.2%, in order to meet the requirements of ammonia synthesis.