Current Development of Dry Desulfurization for Coke Oven Gas
Thread Content
Dear experts, I am from an activated carbon manufacturing company; our main products include activated carbon desulfurizers and zinc oxide desulfurizers. I’m facing a dilemma now, and I hope everyone can help me figure it out. The confusion lies in the following: many people say that the dry desulfurization technology for coke oven gas is now outdated and will be phased out, especially the rough desulfurization systems using activated carbon and iron-based desulfurizers. Since I have not been in this industry for very long (I used to be involved in petrochemical production management, and I started working in this field six months ago), I am not familiar with the current situation of the industry. I would appreciate it if experts could share their insights with me. Additionally, if there are relevant projects, we can also carry out cooperation. Thank you! My contact number is 13589508010; it’s the same number on WeChat. If you’re in any relevant WeChat groups, please add me there. Thank you!
You can post the specific questions so we can discuss them together!
What confuses me is whether activated carbon desulfurization agents are really necessary for the deep purification of coke oven gas What are the advantages and disadvantages of activated carbon desulfurizers compared to iron oxide desulfurizers?
Iron-based desulfurization catalysts are inexpensive, have a low sulfur capacity, tend to release sulfur once saturated, require frequent replacement, and require more filling volume compared to activated carbon. For activated carbon desulfurization, the humidity in the gas should be above 70%; it is preferable to have trace amounts of oxygen or ammonia present. The sulfur capacity of coal-based materials should be between 15-20%, while that of wood-based materials should be above 20%. For precise desulfurization, activated carbon is recommended. Someone posted it in the forum; I’m also from an activated carbon manufacturing company.
For enterprises that utilize coke oven gas in various ways, whether to produce methanol, LNG, synthetic ammonia, or any other product, it is essential to ensure high levels of desulfurization and to maintain the long-term operational efficiency of the facilities. The sulfur compounds present in coke oven gas are complex; in particular, thiophene differs from those found in water gas. Both activated carbon and other desulfurization agents have a very limited capacity to absorb sulfur. If chemical reactions are not used for sulfur removal, the adsorption capacity becomes saturated after 2–3 months of operation, requiring frequent replacement of the catalysts, which incurs high costs. Therefore, in the current utilization of coke oven gas, TSA is generally used first to purify the impurities present; organic sulfur is removed through primary hydrogenation using iron and molybdenum, and secondary hydrogenation using cobalt, nickel, and molybdenum. ZnO is used for absorption in all cases to ensure that the total sulfur content at the outlet is less than 0.1 ppm. For more stringent requirements, copper-based desulfurization catalysts are then used for further purification.
This post was last edited by caocheng on 2019-6-12 08:58. Hello, friend, thank you for participating! Could you leave your contact information? I’d like to ask, thank you!
Activated carbon is generally used for dry desulfurization at room temperature. When producing syngas from coke oven gas, it contains large amounts of organic sulfur, which must be converted into inorganic sulfur through hydrogenation in order to be removed; this hydrogenation process is usually carried out at moderate temperatures (200–400°C), after which zinc oxide at moderate temperatures is used to remove hydrogen sulfide. Under medium-temperature conditions, the sulfur capacity of the desulfurizer is much higher than at normal temperature, resulting in a longer service life for the desulfurizer. Therefore, dry desulfurization of coke oven gas generally employs medium-temperature desulfurization, and activated carbon is not used. Activated carbon can be used for pre-treatment at room temperature prior to medium-temperature dry desulfurization.