Process for preparing needle coke raw material by using coal-tar pitch and through heavy-phase circulation

Abstract

The invention relates to a process for preparing a needle coke raw material by using coal-tar pitch and through heavy-phase circulation. The process comprises the steps that: (1) coal-tar pitch is sufficiently mixed with a first solvent; first solvent insoluble matters are removed from the mixture with a physical separation method, such that a first clarified liquid is obtained; (2) the first solvent is removed by separation; the obtained residual component is subjected to hydrogenation, such that refined pitch is obtained; (3) the first solvent insoluble matters and a second solvent are sufficiently mixed; second solvent insoluble matters are removed from the mixture with a physical separation method, such that a second clarified liquid is obtained; (4) the second solvent in the second clarified liquid is removed by separation, such that a refined heavy component is obtained; and (5) the refined pitch and the refined heavy component are mixed, such that the raw material used for preparing needle coke is obtained. With the process provided by the invention, the obtained needle coke raw material has high polyaromatic condensed polycyclic aromatic content, such that needle coke product yield is effectively improved.

Description

technical field [0001] The invention relates to the field of needle coke preparation, in particular to a process for preparing needle coke raw materials by using coal tar pitch combined with heavy phase circulation. Background technique [0002] Needle coke is a high-quality material for manufacturing high-power and ultra-high-power electrodes. Graphite electrodes made of needle coke have strong thermal shock resistance, high mechanical strength, good oxidation performance, low electrode consumption and large allowable current density, etc. advantage. The needle coke currently produced can be divided into two categories: petroleum-based needle coke and coal-based needle coke according to the different raw materials used. The Great Lakes Carbon Company of the United States first developed the production process of petroleum-based needle coke in the 1950s. However, due to the trend of petroleum processing towards the direction of catalytic cracking and light-weight deep proce...

AI Technical Summary

Problems solved by technology

[0005] In fact, the applicant has found through research that, in addition to quinoline insolubles and impurities that hinder the growth of small spheres, the heavy phase that settles down in the above process also contains a large amount of polyaromatic condensation polycyclic aromatic components, and these components It is the basic substance of graphitization to generate needle coke, but in the above process, the settled heavy phase is completely removed, resulting in a low content of polyaromatic condensation and polycyclic aromatic components in the obtained needle coke raw material, so if using The needle coke is prepared from the above raw materials, which in turn leads to a low yield of the needle coke product; and what this process embodies is just the usual technical means in the prior art, that is to say, many years of technological development The technical prejudice that personnel have always existed is to remove the heavy phase containing a large amount of quinoline insolubles and impurities, so that the needle coke raw material contains as little quinoline insolubles as possible that affect the graphitization process

Therefore, so far, there has not been a technology for recycling the heavy phase after treatment in the prior art

Images