Study of Coke-oven Gas Desulphurization and Methods to Improve Sulphur Quality

Abstract

The coke-oven gas has high calorific value and can be used for the burning process. The coke-oven gas coming out from the coke-oven department contains impurities like Sulphur, Ammonia, Tar, and Naphthalene. Sulphur is the major impurity; it is very harmful and poisonous to the environment. So the removal of sulphur plays an important role in the purification of coke-oven gas. The sulphur extraction can be done by absorption using NaOH. NaOH is a good absorber of H₂S gas. The cleaned coke-oven gas can be recycled back for the burning of coal. The sulphur extracted is of low quality, so by using different methods of desulphurization, the sulphur can be purified. Sulphur quality enrichment process by using the output sulphur from the desulphurization pilot plant shows different kind of results. The sulphur quality increases to more than 90% by using different organic solvents like benzene, CCl_4, CS₂, and water of different temperatures. The sulphur quality increased to 90% by dissolving the sulphur paste in water at moderate temperature of 45–55°C and increased to 97% by dissolving it in water of temperature 60–70°C. These investigative studies have given some of the conclusions regarding the reasons for sulphur purity, steps to remove the impurities, and methods to improve the sulphur purity. 

Keywords: Desulphurization, coke, sulphur