2results about "Thiocyanic acid" patented technology

The application provides a method for preparing calcium thiocyanate by using desulfurization waste liquid, calcium nitrate and ammonium thiocyanate are respectively dissolved into 30-50% solution, the calcium nitrate solution is slowly dropped into the hot ammonium thiocyanate solution under the conditions of heating and stirring, under the heating state, the double decomposition reaction occurs to generate calcium thiocyanate and ammonium nitrate, with the continuous heating and the evaporation of water, the concentration of calcium thiocyanate gradually increases, the ammonium nitrate is heated and decomposed to generate nitrogen oxide and ammonia gas, the generated process gas rich in nitrogen oxide and ammonia gas is condensed and introduced into the coking ammonia removal and denitration section for treatment, and finally the evaporation and concentration obtain about 50% calcium thiocyanate product. The method uses industrial waste to provide raw materials, and the production cost is low; the process tail gas generated in the reaction only needs to be treated by the existing ammonia removal and denitration device of the coking enterprise, without increasing additional equipment, thereby saving the expenditure; and the method has environmental protection benefit, social benefit and economic benefit.

The utility model belongs to the field of industrial waste liquid treatment and recovery, disclose is a kind of coking desulfurization waste liquid salt extraction system, including pretreatment system and first salt extraction system;The pretreatment system includes first reaction kettle and first filter device, the first reaction kettle with the first filter device is connected, for the impurity removal and filtration of coking desulfurization waste liquid;The first salt extraction system includes crystallization reactor and second filter device, the crystallization reactor includes feed inlet, liquid discharge port and solid discharge port, the feed inlet is used to put in the coking desulfurization waste liquid after impurity removal and copper sulfate solution, the solid discharge port with the second filter device is connected, and the second filter device is used to filter out cuprous thiocyanate. Cuprous thiocyanate reaction precipitation can be realized to filtration treatment, and the processing efficiency is improved.