What desulfurization method is used to produce methanol from coke oven gas?

Wet desulfurization is primarily used for rough desulfurization, to reduce the sulfur content to less than 100PPM. This process is mainly employed in coking projects; in methanol production, medium-temperature iron oxide/medium-temperature zinc oxide is used for desulfurization. Of course, there is also low-temperature iron oxide/low-temperature zinc oxide for desulfurization, with the low-temperature method being used mainly for pretreatment or as a quality control step. Both iron oxide and zinc oxide-based desulfurization methods belong to the category of advanced desulfurization, requiring that the sulfur content in the process gas be less than 100PPM.

Generally, wet desulfurization is carried out first, followed by advanced desulfurization, that is, dry desulfurization. The desulfurization processes I have seen involve iron-molybdenum hydrogenation followed by iron-manganese treatment, and then either nickel-molybdenum treatment or a second stage of iron-molybdenum hydrogenation, with zinc oxide used as a final control element. Reduce it to 0.1PPM sulfur in the feed gas.

1. The desulfurization of coke oven gas generally starts with wet desulfurization methods such as P400 or other coking desulfurization processes, which remove a large amount of inorganic sulfur as well as some organic sulfur. 2. After precise desulfurization, organic sulfur is converted into inorganic sulfur using an iron-molybdenum hydrogenation catalyst, followed by removal using an iron-manganese desulfurizer; medium-temperature zinc oxide is used for final control, ensuring that the total sulfur content at the outlet is less than 0.1 PPm

It’s a real hassle; we’ve almost used up all the solid desulfurizer.

Desulfurization can be divided into wet desulfurization and dry desulfurization. Generally, companies use both methods together. For wet desulfurization, low-temperature methanol washing and cobalt phthalocyanine-based processes are commonly employed to remove most of the organic and inorganic sulfur from the gas, reducing the total sulfur content to below 20 mg/L. After that, dry desulfurization is used, involving hydrogenation with iron-molybdenum or cobalt-molybdenum compounds, as well as medium-temperature oxidation using iron oxide and zinc oxide to reduce the sulfur content to below 0.1 ppm, thereby meeting the requirements of the conversion and synthesis stages.

First, wet desulfurization using tannin method is employed to reduce the sulfur content in coal gas from 200 mg/m3 to below 20 mg/m3. For the purification of organic sulfur in coke oven gas, two-stage hydrogenation using iron-molybdenum and nickel-molybdenum, or two-stage absorption using iron-manganese and zinc oxide can be adopted.

Generally, if the total sulfur content is not high, dry desulfurization methods can be used; there are many such methods, such as ferro-manganese desulfurization and activated carbon desulfurization. If the total sulfur content is high or the organic sulfur content is high, cobalt-molybdenum hydrogenation conversion or iron-nickel hydrolysis can be carried out first, followed by wet desulfurization and then dry desulfurization; in both dry and wet methods, precise desulfurization using zinc oxide is required afterward

Does desulfurization using these methods remove trace amounts of sulfur? So how is sulfur recovered? Can’t sulfur be recovered using low-temperature methanol washing?

It is generally wet desulfurization followed by coking; the organic sulfur content in coke oven gas is around 100, while the inorganic sulfur content is below 50. After passing through the pre-desulfurization tank, primary hydrogenation, medium-temperature manganese oxidation, secondary hydrogenation, and medium-temperature zinc oxidation, the sulfur content at the outlet is 0.1 PPM

After wet desulfurization of coke oven gas, elemental sulfur can be recovered through a Gore filter or a sulfur melting tank. In dry desulfurization, organic sulfur is adsorbed by the desulfurizing agent.

Generally, a combination of wet desulfurization and dry desulfurization is used. Catalytic conversion is relatively complex, and strict requirements are imposed on the sulfur content before conversion. The \"dry-wet-dry\" desulfurization process, also known as the \"sandwich method\", is typically employed; for non-catalytic conversion, the \"wet-dry\" desulfurization process is sufficient. The processes for dry desulfurization include zinc oxidation and iron-molybdenum hydrogenation. Among the wet desulfurization methods, in addition to those mentioned above, there are also NHD and low-temperature methanol washing. For large-scale applications, low-temperature methanol washing is a more reasonable option as it results in lower operating costs; for smaller-scale applications, NHD or other methods are used. As for which process to ultimately adopt, it depends on the sulfur content in the raw materials, as well as the expertise and preferences of the design institute.

The raw gas produced by coke ovens contains a high level of sulfur, and methanol synthesis catalysts have strict requirements regarding sulfur content; therefore, it is necessary to remove this sulfur. Generally, wet methods are used first to reduce the total sulfur content to below 20 mg/L, followed by dry methods (using appropriate desulfurization catalysts) to bring the sulfur content down to below 0.1 PPM, thereby ensuring safety, high quality, and high productivity!

The original poster isn’t involved in coke oven gas production; don’t you use lump coal for pressurized gasification in Ruchi reactors? Thinking about changing jobs? ? ? ^_^

Activated carbon, zinc oxide, and iron oxide are all acceptable

The desulfurization of coke oven gas generally starts with wet desulfurization methods such as P400 or other coking desulfurization processes, which remove a large amount of inorganic sulfur as well as some organic sulfur. Further refined desulfurization is carried out, with iron-molybdenum hydrogenation catalysts being used to convert organic sulfur into inorganic sulfur, which is then removed using iron-manganese desulfurizing agents. Medium-temperature zinc oxide is used as a control mechanism, ensuring that the total sulfur content at the outlet is less than 0.1PPm – it’s quite a complex process.

It is generally a process that combines wet desulfurization with dry desulfurization, which is quite complicated; organic sulfur has to be converted into inorganic sulfur. There are many different types of desulfurizing agents, and among them, some also include dechlorinating agents that are added in stages. There are also many types of wet desulfurization agents, and the choice depends on the composition of your gas. As for dry desulfurization, the desulfurization agents used in this process are now well-developed, and there are numerous manufacturers producing them, so they can be used with confidence. Desulfurization is one of the most critical stages in production; it must not be taken lightly. If the gas levels after desulfurization exceed the specified limits, it can poison the catalyst, leading to severe consequences and substantial losses. Be extremely careful!

It is generally divided into wet desulfurization and dry desulfurization； Since coke oven gas contains high levels of both inorganic and organic sulfur, both wet and dry desulfurization methods must be employed ； Wet desulfurization methods include low-temperature methanol washing, NHD method, and others ； Dry desulfurization includes desulfurization using iron-molybdenum catalysts (or nickel-molybdenum, cobalt-molybdenum catalysts) along with hydrogenated zinc oxide (manganese oxide). Theoretically, converting nickel-based catalysts requires a sulfur content in the feed gas of less than 0.5PPM, while synthesizing copper-based catalysts requires a sulfur content in the syngas of less than 0.1PPM ； In practice, of course, the lower the sulfur content, the better, but usually the primary consideration is maximizing economic benefits. Providers of the low-temperature methanol washing process include Linde, Lurgi, as well as Dalian University of Technology in China ； The NHD method is a technology developed by Nanhua ； The Northwest Research Institute of Chemical Engineering has developed a series of catalysts such as JT-1 and JT-8 specifically for the dry desulfurization of coke oven gas.

Water is added to the transformed gas in order to hydrolyze COS during desulfurization. The desulfurization tank is a simple fixed-bed reactor equipped with ZnO as a desulfurizing agent; Topsoo HTZ-4 type desulfurizing agent and MG-901 type dechlorinating agent are used. The reactions that occur are: COS + H2O = CO2 + H2S; H2S + ZnO = H2O + ZnS. As for the recovery of S, the Claus process can be used.

Use wet lifting, MTDA solution.

1. Soot-based wet desulfurization to reduce levels to below 20 mg/L. 2. Dry desulfurization using solid catalysts: it proceeds through activated carbon, iron-molybdenum hydrogenation, iron-manganese desulfurizer, nickel-molybdenum hydrogenation, and finally zinc oxide is used to reduce the level to below 0.1PPM. To meet the sulfur requirements of methanol synthesis catalysts, our factory handles this task well; the results are quite good. Learn from us!