Processing method of coal tar

Abstract

The invention relates to a processing method of coal tar. The processing method is characterized by comprising the following steps of: dewatering tar; distilling the tar; sequentially distilling the dewatered tar by adopting continuous type distillation devices, namely a first-stage evaporator and a second-stage evaporator, to respectively obtain light oil, asphalt, anthracene oil II, anthracene oil I, mixed oil III; washing and decomposing: alkalizing the mixed oil III to generate water-soluble phenoxide which can be separated from water-insoluble naphthalene washing distillates so as to provide a raw material for industrial naphthalene; evaporating the separated neutral phenoxide to obtain pure sodium phenolate; decomposing by using sulphuric acid to finally obtain crude phenol of which phenol content is more than or equal to 83%; and distilling industrial naphthalene: dewatering washed mixed distillates, carrying out heat exchange with industrial naphthalene steam to 190-210 DEG C, cutting phenol oil distillates in a primary distillation tower, and cutting the industrial naphthalene and wash oil distillates in a rectifying tower. The process method disclosed by the invention is simple and reasonable in process, reduces the energy consumption and plays an energy conservation role by sufficiently utilizing the afterheat of products in the distillation process of the tar and prevents the flue gas from polluting the environment by arrangement of an exhaust cleaning tower in a washing and decomposing procedure.

Description

technical field [0001] The invention belongs to the technical field of coal chemical industry, and in particular relates to a method for processing coal tar. Background technique [0002] Tar, also known as coal tar or coal paste, is a liquid product obtained during the carbonization process of coal. According to the carbonization temperature, coal tar can be divided into three categories: low-temperature tar, medium-temperature tar and high-temperature tar. High-temperature coal tar is one of the products in the crude gas generated by coal pyrolysis in the coking process, and its output accounts for about 3%-4% of the furnace coal. Composed of aromatic compounds, the content of alkylaromatics is less, the content of high boiling point components is more, and the thermal stability is good. Its component naphthalene, the main components are: 1-methylnaphthalene, 2-methylnaphthalene, acenaphthene, fluorene, oxygen fluorene, anthracene, phenanthrene, carbazole, fluorine anthra...

AI Technical Summary

Problems solved by technology

[0005] The development of deep processing of coal tar can greatly improve resource utilization and economic benefits. However, the existing coal tar processing methods are relatively simple, and there are problems such as high energy consumption, unstable quality, and large pollution to the working environment.

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