H2S content before and after propylene decarburization
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Recently, due to the new testing equipment installed, the data obtained seems to have limited reliability, especially regarding the desulfurization efficiency of the propylene carbonate solution. Before decarburization, the hydrogen sulfide level was around 20 mg/m3, while after decarburization it dropped to less than 0.1 mg/m3; thus, the reliability of these figures appears low. I would appreciate it if colleagues could share their data on hydrogen sulfide levels before and after decarburization and desulfurization using propylene carbonate solutions. There is a reward available for such information. The high level of suspended solids is caused by hydrogen sulfide; could it be that the circulation rate used in the decarburization process is too high, meaning the gas-liquid ratio is too low, which results in excessive desulfurization efficiency? What is the target level for carbon dioxide emissions at the outlet?； However, the high import cost of hydrogen sulfide does have a significant impact on decarburization
Due to the significant impact of hydrogen sulfide on methanol catalysts, strict control over hydrogen sulfide levels is essential after decarburization. Many manufacturers implement precise desulfurization at room temperature after decarburization, and the hydrogen sulfide concentration at the inlet for this process should not exceed 10 PPM
The data is completely reliable; the main focus is on reducing hydrogen sulfide levels before decarbonization, and currently, in small nitrogen fertilizer plants, the level of hydrogen sulfide imported for decarbonization is below 5 mg/m3. I’m not sure what the situation is at your factory
The data is completely reliable; it is recommended that you improve the management of decarburization in order to reduce the hydrogen sulfide levels before decarburization. Currently, in small nitrogen fertilizer plants, the hydrogen sulfide level at the point of import before decarburization is below 5 mg/m3. The carbon propylate suspension can be removed using a filter. Ensure that the hydrogen sulfide in the decarbonized outlet is below 10PPM. This post was last edited by 7276166 on 2009-3-14 19:10]
The data is reliable. We analyze that both CO2 and H2S are acidic gases; moreover, the H2S content in the regenerated CO2 gas is quite high, indicating that most of the H2S has converted into CO2.
More or less, carbon propyl liquid has a much greater ability to absorb organic sulfur and inorganic sulfur than acidic gases such as CO2, so it is entirely possible to achieve the numerical values mentioned by LZ. However, the corresponding decarbonization capacity will decrease. For example: Our company has been using propylene carbonate as a decarburizing agent for about 25 years now. The total sulfur content at the inlet of the absorption tower is generally around 40 Mg/m3. Sometimes, in order to increase methanol production, some of the shifted gas enters the decarburization section without passing through the shift tower; as a result, the sulfur content at the inlet can be quite high, reaching up to 80 Mg/M3. Even in such cases, the sulfur content in the purified gas emerging from the decarburization process is kept at 0. 5Mg/m3, or even lower, (two self-modified dry desulfurization tanks in series after the absorption tower). Therefore, Propylene Carbonate can address the sulfur issue while reducing CO2 levels. Of course, the gas-liquid absorption ratio may increase, and the decarburization efficiency may decrease as well. But under normal circumstances, it can still be kept within the specified range. For example, increase the absorption pressure and reduce the propylene temperature. As for the removal of sulfur from the carbon propylene solution, the use of ceramic or microporous filters for continuous partial filtration in the stripping tower over 24 hours can effectively address the issue of high sulfur levels in the system.
Propylene carbonate has a much greater ability to selectively absorb hydrogen sulfide than it does to selectively absorb carbon dioxide; therefore, as the other posters mentioned above, your analysis results are completely normal. If the hydrogen sulfide level remains roughly the same before and after decarboxylation of propylene carbonate, that would be abnormal.
Regarding the H2S level before and after propylene decarburization, the removal of hydrogen sulfide during propylene decarburization is essentially a form of \"by-product desulfurization\". Propylene liquid has a much greater capacity to absorb organic and inorganic sulfur than acidic gases such as CO2, but it is difficult to reduce the H2S level to below 0.1 mg/m3 after decarburization, which is one order of magnitude lower than the normal value.
This post was last edited by *aoye613 on 2009-5-10 17:28. The data regarding H2S in the decarbonization process at the export side is completely reliable; however, more focus should be placed on removing H2S from the input stream during decarbonization. High levels of H2S in the input stream not only affect the efficiency of the decarbonization process and can cause blockages in equipment and packing materials, but they also have an impact on subsequent processing stages.
This post was last edited by wamj6566 on 2009-5-14 04:32. The data is reliable; we import around 10 units for decarbonization, while exports are less than 1. Due to limited testing equipment, values below that cannot be displayed
The factory where I used to work had three sets of propylene carbon disulfide removal systems; the initial process involved desulfurization first, followed by decarburization, then refined desulfurization, and finally alcohol synthesis. The hydrogen sulfide at the desulfurization inlet is 10 mg/m3, with almost no sulfur at the outlet. However, sulfur blockage can occur in the decarbonization absorption tower; often, whenever there is an opportunity for shutdown for maintenance, the packing at the top section of the absorption tower is cleaned. Later, moving the precision desulfurization process, that is, the desulfurization using activated carbon at room temperature, to before the carbon removal inlet yielded better results. As for the gas-liquid absorption ratio, we are operating at around 85.