Method for preparing lime for calcium carbide by utilizing carbide slag

Abstract

The invention relates to a method for preparing lime for calcium carbide by utilizing carbide slag, which comprises the following steps of: S1: adding water into the carbide slag and stirring to obtain carbide slag slurry of which mass concentration is 12 to 20%; S2: removing large-particle impurities in the carbide slag slurry by mechanical sieving, enabling the carbide slag slurry of which large-particles are removed to flow into a mill to carry out fine milling processing, and controlling a particle size of carbide slag particles into a range of not over 40mu m; S3: carrying out separation on the fine-milled carbide slag slurry by a cyclone hydraulic separator, enabling the purified carbide slag slurry to flow out via an overflow pipe, enabling the purified carbide slag slurry to enter a vacuum belt dehydrator to carry out dehydration so as to obtain carbide slag with water content of not over 15%; S4: adding a pelletizing agent into the dehydrated carbide slag, stirring, pelletizing into balls and drying; S5: calcining the dried carbide slag at a temperature of 900 to 1,000 DEG C to obtain the lime for the calcium carbide. The lime prepared by the method disclosed by the invention is low in impurity content, uniform in particle size, high in strength and good in activity, and can meet requirements of the lime for the calcium carbide.

Description

technical field [0001] The invention relates to a method for comprehensively utilizing calcium carbide slag, a by-product of acetylene production, in particular to a method for preparing calcium carbide lime by using calcium carbide slag. Background technique [0002] Carbide slag is the waste residue produced in the PVC chemical production process. To produce 1 ton of PVC products, 1.5 tons of calcium carbide is consumed and 1.7 tons of calcium carbide slag is produced. For an enterprise with an annual output of 1.2 million tons of polyvinyl chloride resin, the annual production of carbide slag exceeds 2 million tons. The moisture content of these discarded calcium carbide slags (wet method) is 40%, which not only takes up valuable land resources, but also easily air-dried and take-off ash is piled up for a long time, causing pollution to the surrounding environment and groundwater. The "reduction, recycling, and harmless" disposal of calcium carbide slag is affected by th...

AI Technical Summary

Problems solved by technology

In the above method, the purification and purification of calcium carbide slag is mainly through simple screening, sedimentation, centrifugal separation, filtration and other steps, and the treatment results of impurities such as magnesium, silicon, iron, aluminum, and metal oxides in calcium carbide slag are not good. Very ideal, resulting in low product content, directly affecting the quality of calcium carbide products