Preparation method of impregnant asphalt

Abstract

The invention belongs to the technical field of asphalt further processing, in particular to a preparation method of impregnant asphalt, aiming at providing a preparation method of the impregnant asphalt, which can be used for obtaining impregnant asphalt products with low QI (Quinoline Insoluble) content and high coking value. The preparation method comprises the following steps of: A, mixing kerosene and absorber oil into a mixed solvent in the weight ratio of 0.85-1.15:0.85-1.15; B, mixing the mixed solvent and asphalt with the coking value of 54%-58% in the weight ratio of 0.8-1.2:0.8-1.2, and stirring evenly at 250-300 DEG C; and C, precipitating the mixture obtained in the step B at 250-300 DEG C, filtering residuals and recycling the solvent of filter liquor to get the impregnant asphalt. The quinoline insoluble content in the impregnant asphalt got by using the method is 0.1%-0.5%, the softening point is 80-90 DEG C, and the coking value is 50%-54%, so the impregnant asphalt can meet the requirements for manufacturing high-power or ultrahigh-power electrodes, especially for manufacturing electrode joints.

Description

technical field [0001] The invention belongs to the technical field of asphalt deep processing, in particular to a preparation method of impregnating agent asphalt. Background technique [0002] High-quality impregnating agent pitch is mainly used to prepare large-scale high-power (HP) and ultra-high-power (UHP) graphite electrodes used in steelmaking and aluminum smelting industries. Compared with ordinary electrodes, this electrode can greatly shorten the electric furnace smelting time, greatly reduce the steelmaking cost, and significantly increase the output. At present, a large number of tons of high-power and ultra-high-power graphite electrodes are needed every year in China to meet the growing demand for electric furnace steelmaking and aluminum smelting. High-power and ultra-high-power graphite electrodes require impregnating agent pitch products with low content of quinoline insolubles (hereinafter referred to as QI) and high coking value, that is, QI content ≤ 0....

AI Technical Summary

Problems solved by technology

CN200810038494.7 discloses a mixed solvent prepared by selecting an aliphatic hydrocarbon solvent and an aromatic hydrocarbon solvent. The extraction method is adopted, and the separation process is operated in the range of 80-140°C. Because the mixing and separation temperature is too low, on the one hand, the performance of the asphalt solvent is small, and a large amount of The loss of useful polymer components (such as β resin) results in low process yield, low coking value and high production cost; on the other hand, the solution viscosity is high at low temperature, QI sedimentation is slow, and the separation efficiency is low

[0005] Second, the selected solvent is not suitable

Such as CN200910076008.5, using pure coking solvent, the solvent density is high (relative density greater than 1.0), resulting in a small density difference between the QI particles and the solution, QI settling is slow, the separation is difficult, the separation efficiency is not high, or the required separation time is long , in order to achieve a better separation effect, there must be a large investment in equipment, a large solvent ratio, etc.