4 results about "Claus process" patented technology

The invention relates to the technical field of preparation of elemental sulfur, and particularly discloses a solvent method for preparing elemental sulfur from hydrogen sulfide and sulfur dioxide. According to the solvent method, hydrogen sulfide and sulfur dioxide are introduced into a mixed solution of 2-acetylthiophene and 2-phenylthiophene at the temperature of 120-150 DEG C for a neutralization reaction, and elemental sulfur is generated. According to the invention, a mixed solution of liquid 2-acetylthiophene and 2-phenylthiophene is used as a reaction medium, and hydrogen sulfide and sulfur dioxide react to generate sulfur and water. The carbonyl oxygen atom of the 2-acetylthiophene and the sulfur atom on the thiophene ring have certain electron donating ability, and have certain catalytic action on the reaction. The 2-phenylthiophene is high in boiling point, stable in property and capable of well dispersing and conveying the liquid sulfur, and after standing, a mixed solution of the 2-acetylthiophene and the 2-phenylthiophene is easily layered from the liquid sulfur, so that the elemental sulfur is easily separated out. Compared with a traditional Claus process, the solvent method in the scheme has the advantages that the solvent is used as a reaction medium, and the problem of sulfur blockage is not easily generated.

Sulfur-containing compounds are removed from crude CO2 by conversion to elemental sulfur in a Claus process and subsequently by hydrogenation of the Claus tail gas to convert residual sulfur-containing compounds into H2S which, after cooling to knock out water and then compressing, is removed, together with any other sulfur-containing impurities, either by physical separation or by chemical reaction with a solid metal oxide to form solid metal sulfide with subsequent oxidative regeneration to produce purified CO2 and a recycle gas comprising at least one sulfur-containing compound which is recycled to the Claus process. Some H2S in the Claus tail gas may be removed initially by selective and / or non-selective amine absorption(s) in a tail gas treatment unit prior to removal of residual H2S and any other residual sulfur-containing impurities by the physical separation or the chemical reaction steps.

This invention provides a method for preparing hydrogen and sulfur from solid waste gypsum through reduction and acidification in a cement kiln, relating to the field of solid waste disposal technology. The method involves targeted local modifications to a novel dry-process cement clinker rotary kiln production system. Using desulfurized gypsum, phosphogypsum, and other solid waste gypsum as raw materials, the gypsum is crushed, ground, preheated, and dehydrated. Then, it is calcined in a modified three-lobe gravity semi-suspended rotary kiln at 800–1100℃ in a reducing atmosphere to generate high-purity calcium sulfide. After sealed cooling, the calcium sulfide reacts with byproduct hydrochloric acid to produce high-purity hydrogen sulfide. The hydrogen sulfide is then used to co-produce hydrogen and sulfur via a medium-assisted electrochemical decomposition method, or high-purity sulfur can be directly prepared using the Claus process. This invention achieves full resource utilization of solid waste gypsum using existing cement kiln equipment, requires minimal modification, has low investment costs, and enables the cascade utilization of CO waste gas and kiln waste heat, reducing overall energy consumption by more than 30% compared to traditional processes.

The application discloses a short-process Claus desulfurization and sulfur recovery process coupled with low-temperature catalytic oxidation. After a waste gas containing H2S passes through a first-stage Claus conversion reactor and a condenser, the waste gas directly enters a catalytic oxidation reactor with carbon material or carbon-supported metal as a catalyst. The low-temperature catalytic oxidation activity of the carbon material or the carbon-supported metal is utilized to completely convert low-concentration H2S into sulfur at a low temperature and recover the sulfur. Compared with a traditional Claus process, the process route only needs a first-stage Claus reaction and a low-temperature catalytic oxidation reaction, and does not need multiple Claus conversion reactors and multiple reheating-condensation cycles, so that complete removal of H2S in the sulfur-containing waste gas and sulfur recovery can be realized, and the process route has the advantages of short process, low system complexity and low energy consumption.