How is the gas intake rate of the low-temperature methanol washing system controlled?
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In our low-temperature methanol washing unit, electric valves are used; gas introduction begins after pressure equalization is achieved through these electric valves. Once the conversion is complete, the pressure control valve switches to automatic mode. During gas introduction, the pressure control valve in the output unit is used to send the gas to the flare. After the gas has been introduced and its quality has been verified as satisfactory, it is sent to the synthesis unit. How is the rate of gas introduction controlled during this process? This post was last edited by yichaoshan2005 on 2009-4-12 18:08.]
There’s no need to pay attention to the rate of gas introduction; it’s sufficient to ensure a steady flow of gas, gradually guiding it from the front of the tower to the back where it can be released, and then just wait for the relevant indicators to show the desired results. During the gas introduction process, just be careful to prevent pressure fluctuations in the previous system and avoid applying too much load, so as not to blow away the liquid on the trays
We generally feed 10,000 NM3/H of gas into the methanol washing process. The gas should be introduced slowly and steadily, and special attention should be paid to the temperature of the lean methanol stream entering Tower C1.
The pressure difference before and after gas connection should not be too large. Introduce slowly. . Based on the establishment of the minimum load. Gradually increase the opening degree
1. During the gas intake process, it is necessary to ensure that the temperature at the bottom of the gas lift tower does not drop too rapidly, to avoid damaging the equipment. 2. During the gas introduction process, pressure equalization should be carried out first to prevent excessive fluctuations in the liquid level of the main absorption tower. 3. During the gas connection process, it is necessary to check the level gauges at the site and in the control room to prevent high-pressure fluid from leaking into the low-pressure system. 4. After gas connection is complete, fully open the main valve for the process, and also fully open the manual valve in front of the vent valve; this allows for pressure relief of the system at any time, ensuring its safety. 5. Methanol spray should be activated half an hour in advance of introducing air to prevent the heat exchanger from freezing. 6. Before introducing air, raise the liquid level at the inlet of the hot regeneration feed pump to ensure a continuous flow of the absorbent solution. 7. Before opening the valve mentioned earlier, it is necessary to communicate with the preceding and following processes or the dispatch team to operate together and ensure stable pressure in the entire system.
During gas introduction, there should be a certain pressure difference between the conversion section and the low-temperature methanol washing section; generally, this difference is kept at 0.3 MPA. Later on, the gas introduction rate can be increased by reducing the set value of the large valve in the low-temperature methanol washing section.
The system's air intake capacity should match the cooling capacity provided by the ammonia cooler.