Method for producing high-purity sulfur through sulfur paste extraction

Abstract

The invention provides a method for producing high-purity sulfur through sulfur paste extraction. The method comprises the following steps: (1) crushing and screening dried sulfur paste; (2) introducing pretreated raw materials and an organic solvent into a reactor with a steam heating jacket, and carrying out an extraction reaction at a certain temperature, wherein the organic solvent specifically is one or a mixture of more of xylene, solvent oil 200# and heavy benzol; (3) subjecting the obtained reacted solution to heat-preserving filtering treatment, then, introducing the treated solutioninto a crystallizer, and carrying out cooling crystallization and solid-liquid separation, thereby obtaining the target required sulfur; and (4) introducing the organic solvent cooled in the step (3)into the reactor in the step (2) again for recycle. According to the method, the sulfur is purified by making full use of high-temperature solubility of the organic solvent to the sulfur; and meanwhile, the method has the advantages of simple process, stability in operation, low production cost, high recovery rate, high purity and the like, so that the resource-converting utilization of wastes canbe effectively achieved.

Description

technical field [0001] The invention relates to the technical field of coal chemical product processing, in particular to a method for producing high-purity sulfur by extracting sulfur paste. Background technique [0002] The uses of coke oven gas mainly include kiln fuel and synthesis gas raw material. Usually, the sulfur content in coke oven gas is 3-6g / m 3 , but when used as kiln fuel and syngas raw material, the corresponding sulfur content must meet strict requirements, that is, less than 200mg / m 3 and 0.1mg / m 3 . Therefore, the existing coke oven gas needs to be desulfurized and purified before actual use. [0003] At present, the gas purification system of domestic coking enterprises generally adopts the HPF desulfurization process with short process and low investment and production costs, but a large amount of sulfur paste will be produced during the application of this process. The main component of sulfur paste is sulfur, and it also contains organic compound...

AI Technical Summary

Problems solved by technology

Among them, the molten sulfur method is to heat the sulfur paste to 128-158 ° C, and make full use of the difference in density between liquid sulfur and desulfurization liquid to effectively separate. The disadvantage of the molten sulfur method is that it consumes a lot of energy.

The distillation method uses steam or flue gas as the heat source. The disadvantage of the distillation method is that because the colored organic impurities in the solid are ignored, the purity of the obtained sulfur is not high and the utilization value is not high.

Publication number is that the patent of CN 204224257 U discloses a kind of device that reclaims sulfur from sulfur foam, and it adopts nitric acid oxidation method to dehydrated sulfur paste, utilizes the oxidizing property of nitric acid to dehydrate the SCN in sulfur paste - , S 2 o 3 2- and other substances are oxidized to simple sulfur, and the organic impurities in it are removed at the same time; the effect of this patent on treating sulfur paste is remarkable, but due to the violent reaction of this method, a large amount of nitrogen dioxide is generated during the reaction process, and there are problems of high energy consumption and large pollution

Publication Nos. CN103264991A and CN10419 2811A respectively disclose the use of tetrachlorethylene (boiling point 121.2 ° C) and carbon disulfide (boiling point 46.5 ° C) to leaching sulfur paste; although the leaching method has obtained high-purity sulfur, but due to the leaching process introduced A large number of organic solvents not only have safety problems such as explosives and high toxicity, but also have problems such as the price of the leaching agent is much higher than the price of sulfur, and the loss of the leaching process is serious.

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