What is the opening of the gas outlet valve of the high scrubber in the carbon dioxide stripping process?
Thread Content
In the improved carbon dioxide stripping process, the high-pressure scrubber outlet gas directly enters the low-pressure absorption tower without a medium-pressure device. The opening of the high-pressure scrubber outlet manual regulating valve reflects the operation of the high-pressure circle. The higher the conversion rate, the better the washing absorption, and the smaller the outlet valve opening. I don’t know what is the general opening of the air outlet valve of my high-pressure scrubber, and how is the high-pressure vent volume controlled? You are welcome to speak enthusiastically. Replies with practical content will be given a certain score.
The opening of the outlet valve of the stripping urea high-pressure scrubber is determined based on the device load, system pressure, ammonia-to-carbon ratio, water-to-carbon ratio, high-pressure ring temperature, etc. Generally, the higher the load, the larger the opening, and the smaller the load, the smaller the opening. The opening of this valve cannot be used to control system pressure during production. It is strictly forbidden to open this valve when the pressure is high. This will increase the ammonia consumption of the system and increase the load of low-pressure absorption. This will increase the amount of venting and affect environmental protection.
The current opening of our factory is at 40%, mainly due to the large amount of air currently being added: secondly, it is closed and opened according to the temperature behind the valve, as well as the pressure of the tail suction tower!
The opening of this valve cannot be generalized: 1. This valve is a needle type control valve. If it is an imported control valve, the three major manufacturers, Masoneilan, Böhler and Fischer, will calculate the seat diameter of the control valve based on the gas flow data table of the control valve provided by you. If the data is different, the diameter will be different. There are 6.5mm ones and 8mm ones. ； Domestic ones are usually 8MM. The passage of this valve is definitely different between the 1830 device and the 3052 device. Therefore, if the valve is selected differently, the vent gas flow rate will be different under the same opening. 2. The decarburization process is different and the opening degree is different. The front section has PSA pressure swing adsorption decarburization and propylene carbon decarburization. The purity of the two industrial CO2 is different, and the purity of the previous process is only 96. 5%, and post-processing can reach 98%. The higher the purity, the smaller the venting volume, and vice versa. 3. The load is different and the opening is different. In view of the above, you must calculate the theoretical amount of vented gas based on your production load and purity, and then calculate the opening of the regulating valve based on the flow rate. Therefore, the data given to you by others is of little significance for your reference.
I agree with the third floor's point of view. Another point is to look at the liquid temperature of the low-pressure absorption tower. If the temperature is too high, it means that the ammonia consumption will increase if the opening is large. Slowly explore the corresponding relationship between load and valve opening.
What is the opening of the gas outlet valve of the high scrubber in the carbon dioxide stripping process?
The 2nd and 4th floors have been summarized very well. I personally think that there are still the following situations that may interfere with the opening of the valve.: 1. The operating status of the high-pressure scrubber. If the cleaning effect of the high-pressure scrubber is very good, the gas flow rate released by this valve will be relatively low. If the cleaning effect is poor, the opening of this valve will be large, and the ammonia consumption of the system will rise linearly. 2. As mentioned on the 4th floor, without affecting the possibility of explosion of the gas behind the valve, the purity of the raw CO2 has a great impact on the opening of the valve. Sometimes, even if your system load is very low, if the purity of your raw gas CO2 is extremely low, the opening of the valve will be very high, and production cannot even be maintained. 3. Another point is that the washing circulating fluid of the low-pressure absorption tower behind this valve is cut off or has less liquid, resulting in a large number of crystals in the low-pressure absorption tower, blocking the normal passage of gas after this valve. At this time, reduce the volume first, and then process the section from the valve to the low-pressure absorption tower. After the gas passes normally, add more volume. 4. I personally think that this valve can be used as an auxiliary adjustment method when the high-pressure ring system is over-pressured. If you do not open this valve to relieve pressure when over-pressure occurs, then the over-pressure will explode and send you to heaven. You deserve it! The above is just my humble opinion in actual operation!
Each device is different, but the opening is the same and is determined based on actual conditions.
The design of each device is different, but the opening of the regulating valve is the same, which is determined based on the actual load. When our daily output here is 1,400 tons, the opening is at 25%.
If conditions permit, CO2 gas can be used to measure the flow rate of the device, and the opening is determined based on the measurement data. The emission amount is almost slightly more than the amount of air added, which will be clear by looking at the PFD.