Question of the week: What is the impact of water content in circulating methanol on low-temperature methanol washing? (March 23, 2011)
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This post was last edited by 654262293 on 2011-3-24 07:56. Nowadays, many new projects employ advanced manufacturing processes. To help everyone learn more about these new processes, more questions related to this topic will be added here in order to guide people’s understanding of them. What is the impact of water content in circulating methanol on methanol washing? (The answer should not be hidden) Answer: ① It affects the absorption capacity of methanol. When the methanol solution contains 5% water, the solubility of carbon dioxide decreases by about 5% compared to that in pure methanol ； ②Corrodes equipment and pipes. When the water content in methanol is below 1%, methanol causes less corrosion to equipment and pipelines; however, as the water content increases, corrosion of the equipment worsens. The solid substances resulting from this corrosion can then clog the heat exchangers, reducing their efficiency ； ③High water content in methanol increases power consumption, as well as the heat required for cooling and regeneration.
This post was last edited by 654262293 on 2011-3-24 07:54. 1. It affects the absorption efficiency of CO2 and H2S. 2. Increase corrosion of equipment and pipelines. 3. The system consumes a high amount of resources.
This post was last edited by 654262293 on 2011-3-24 07:55. A high water content not only affects the efficiency of methanol absorption but also increases corrosion of the equipment. To achieve the recycling of methanol and obtain good absorption results, it is essential to effectively regenerate methanol. The methods used in the system for methanol regeneration include flashing, stripping, and thermal regeneration. A methanol-water separation tower is used to control the water balance in the solution system.
This post was last edited by 654262293 on 2011-3-24 07:55; the quality has declined.
It affects absorption capacity, accelerates corrosion of equipment and pipelines, and increases consumption.
If the water content is high, it will directly affect the absorption capacity of methanol, and it will also increase corrosion of the equipment, accelerating the rate of corrosion. In current processes, in order to achieve the recycling of methanol and obtain good absorption results, methanol regeneration has been implemented. The methods used by the system for methanol regeneration include flash evaporation, stripping, and thermal regeneration.
1) The methanol absorption capacity has decreased, preventing the system load from increasing； 2) It will exacerbate the corrosion of equipment pipes containing H2S, CO2, etc., generate solid impurities that contaminate methanol, clog equipment and pipelines, and degrade the system’s performance. 3) The presence of water reduces the solubility of CO2 in methanol; when the water content in methanol is 5%, the solubility of CO2 in it is approximately 12% lower compared to anhydrous methanol. 4) It increases the load on the methanol-water separation tower and raises steam consumption; simultaneously, it may lead to the methanol content in the wastewater exceeding the allowed limits.