Selection of desulfurization process for transformed gas

OP, does your factory use fully low-voltage conversion? Why is the hydrogen sulfide level so high? Using 888 should be better. Further desulfurization methods after decarburization are feasible. Our factory has now added an additional step of precise desulfurization after both decarburization and carburization, and the results are very good.

Well, it’s a full low-temperature conversion process; 1.5 g/m3 is a quite high sulfur content, isn’t it? I have no idea; I’ve just started working in chemical engineering design. I’m sorry. Is 888 already widely used? Do you also use this type of desulfurizing agent for wet flue gas desulfurization? Thank you:loveliness:

A sulfur content of 1.5 g in the transformed gas is relatively rare; it is recommended to carry out desulfurization at normal pressure first before further processing； Or, hydrogen sulfide can be removed using physical adsorption methods before further treatment ； Otherwise, prepare for trouble – the 500mg of reformate gas imported by Jiangsu Huaihua (Xuyi) is still in use ； Jincheng Yihua once had 800mg, and later desulfurization was carried out once again ； I can go and ask around. . . . . . Success!

Does anyone else know about this? Please let me know :)

A H2S content of 1500 mg/m3 in the transformed gas is quite rare. The tannin method chosen by your factory is relatively mature, and it enjoys considerable support; the key aspect in this method is controlling the ratio of tannin to vanadium. Nowadays, the price of vanadium has also dropped, so cost control is not a major issue. However, in actual operating systems, the tannin treatment equipment suffers more from corrosion. As for 888, it is currently the market leader, with the widest coverage, extensive experience; its main issue is tower blockages. As for ADA and DDS, they result in less corrosion and tower blockage; the cost of DDS is slightly higher than that of others, but its desulfurization accuracy is the highest. The extremely high content of 1.5 in your plant’s shift gas, along with the use of wet catalysts, seems to be something that no one can overcome. As LS said, after careful consideration, it would be best to install a dewaxing unit.

Thank you. What process does LS mean by \"removal\"? We did not desulfurize before the conversion; this sulfur content is the amount of hydrogen sulfide after conversion using a sulfur-resistant conversion catalyst and intermediate-temperature hydrolysis, as provided by the data given. I’ve seen in some materials that the gas desulfurization level can be even higher than this, and wet oxidation methods are used for that purpose; resins such as tannin and 888 are also employed. So why does LS state a value of 1.5 g/m3 (under standard conditions)? Such a high level cannot be achieved by any wet catalyst If the wet oxidation method is used, is it possible to follow a precision desulfurization process after decarburization? It has been suggested to use physical absorption methods; would low-temperature methanol washing provide high desulfurization accuracy? However, considering that it is a small plant with a production capacity of 5 wt% ammonia per year, the cost might be too high

888 is better; adding alkali should work

Literacy: Ammonia synthesis desulfurization includes atmospheric pressure desulfurization, pressurized desulfurization, and advanced desulfurization； Atmospheric pressure desulfurization, also known as semi-water gas desulfurization or primary desulfurization, is usually installed after the Roots blower at the outlet of the gas holder, with the system gauge pressure remaining within 0.05 MPa ； Pressure-based desulfurization is what you refer to as syngas desulfurization; it is also known as secondary desulfurization. It takes place after the shift unit, at a system pressure of over 0.8 MPa ； Precise desulfurization refers to the desulfurization devices installed in various processes after variable desulfurization as needed, with dry desulfurization being the most common type ； ******************************************Literacy program completed ****************************************** There are no restrictions on the amount of hydrogen sulfide imported for desulfurization; levels ranging from 0.1 to 10 g per cubic meter are acceptable. However, in China, wet desulfurization of shift gas rarely involves levels higher than 500 mg ； Physical adsorption is not necessarily low-temperature methanol washing; have you heard of steric amines? Check with the South China Institute of Chemical Technology. From an economic perspective, it is recommended that you first carry out desulfurization to reduce hydrogen sulfide levels to around 150 mg before proceeding with conversion and further desulfurization. Because after physical adsorption is used for removal, you still have to deal with hydrogen sulfide; when the gas flow rate is low and the concentration of hydrogen sulfide is high, it becomes very difficult to handle, and the consumption is also high. Are you from a design institute or the technical reform department of a factory? ! I’m very worried......

Thanks for the explanation from above. I work at a design company; we’ve just taken on the task of designing this purification process. The previous team had already finalized the overall plans, and my role is limited to carrying out more detailed design calculations and similar tasks. I didn’t consider what the actual implementation of this system would be like in practice, and I hadn’t done enough research on purification processes before starting work. It wasn’t until I was asked to compare different desulfurization methods these past couple of days that I realized there are so many issues. Hearing what the people upstairs have to say, it’s not easy after all; it seems I need to thoroughly understand and study desulfurization

You should advise the company to spend some time on-site at relevant companies, or to hire some technical staff directly from those companies. It seems that the Anhui Chemical Engineering Design Institute does exactly that. Practical experience is important; it can’t be based solely on scaling up or down. How are design institutes unable to retain employees these days?