【Purification Daily Question】May 12, 2016
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To increase the popularity of the purified area, a \"One Question per Day\" campaign was launched to foster an active atmosphere for technical exchanges while also providing members with certain financial rewards. (Fellow sailors, if you have any good questions, feel free to send them to me; let’s work together.) 【Daily Question】 What are the reasons for the decrease in the purity of carbon dioxide product gas? Post your answer as a reply; participating in the quiz earns you +2 wealth points. Getting all answers correct adds another +3 to +8 wealth points. Those who provide thorough analysis and explanations for the questions or answers (or include detailed calculation processes) will receive additional wealth rewards. If your answer is correct and your analysis and explanation are accurate, it will be marked as the best reply (or the best assistance). Feel free to answer the questions. The flash pressure of rich methanol is controlled too high, resulting in low amounts of carbon monoxide and hydrogen being flashed and carried to the desorption section of the dioxide tower. The temperature of the methanol-rich stream entering the desorption section is too high, resulting in significant desorption of hydrogen sulfide. The amount of methanol rich in carbon dioxide used to absorb hydrogen sulfide is insufficient.
1. The medium-pressure flash pressure is high or fluctuates, resulting in incomplete flashing of hydrogen and carbon monoxide in methanol; this leads to a high level of CO + H2 in the CO2 gas. 2. The amount of water used for washing in the shift process is low, which increases the ammonia content in the methanol being washed, and as a result, the ammonia content in the CO2 gas is also high
The decrease in the purity of the carbon dioxide product gas is mainly due to the long duration of the adsorption step, which results in a lower purity
The flash pressure of rich methanol is controlled too high, resulting in low amounts of carbon monoxide and hydrogen being flashed and carried to the desorption section of the dioxide tower.
1. The demister is damaged, causing methanol to be carried in the carbon dioxide product gas; 2. The operating pressure is low, resulting in some hydrogen sulfide flashing out; 3
I believe that the product gas must ensure that the methanol content remains low; when the amount of methanol in the product gas exceeds a certain level, its purity decreases relatively
The flash pressure of rich methanol is controlled too high, resulting in low amounts of carbon monoxide and hydrogen being flashed and carried to the desorption section of the dioxide tower. The temperature of the methanol-rich stream entering the desorption section is too high, resulting in significant desorption of hydrogen sulfide. The amount of methanol rich in carbon dioxide used to absorb hydrogen sulfide is insufficient.
There must be a problem with the decarburization system, such as excessive entrainment of alkali solution, etc. I’m not an expert in this field, so I don’t know much about it.
The pressure in the washing tower decreases, the pressure in the stripping tower increases, and the temperature drops. It is very likely that the flash vapor pressure will increase.
1. The medium-pressure flash pressure is too high; hydrogen and carbon monoxide vaporize during low-pressure flashing； 2. The amount of methanol absorbed in the cycle is on the high side ； 3. The temperature of the circulating methanol is too high ； 4. The water content in the circulating methanol is relatively high.
1. A leak in the CO2 pipeline in the raw gas pre-cooler allowed raw gas to leak in. 2. The pressure in the carbon dioxide separation tower was too low, resulting in a small amount of H2S being separated. 3. The liquid level in the upper section of the carbon dioxide separation tower was too high, causing a small amount of methanol to be carried away