Continuous refinement separation device and method of coked crude phenol

Abstract

The invention relates to a continuous refinement separation device and method of coked crude phenol. The continuous refinement separation device comprises a static mixer 1, a first stage pretreatment acid-adding unit composed of a first stage mixing slot 2 and a wipe film evaporator 3, a second stage pretreatment oxidation unit composed of a second stage mixing slot 4 and a buffer tank, a phenol residue removing tower 6 and a rectification tower system composed of a dewatering tower 7, a phenol refinement tower 8, a orthocresol refinement tower 9 and a m,p-cresol refinement tower 10, wherein the first stage pretreatment acid-adding unit is connected with the phenol residue removing tower, the phenol residue removing tower is connected with the second stage pretreatment oxidation unit, andthen all devices of the refinement tower system are connected together in turn. The device and method of the invention can effectively performs processes of decoloring, deodorizing, desulfurizing, removing impurity and the like to the coked crude phenol raw material through reasonable design to obtain more than 99.5wt% of high purity phenol, more than 99.0wt% of high purity orthocresol, more than99.0wt% of high purity m,p-cresol and xylenol product. The whole process is reasonable, has high degree of automation and is characterized by low process energy consumption, high product quality, good stability and the like, thus the method of the invention is an effective and feasible coked crude phenol continuous refinement separation technology.

Description

technical field [0001] The invention belongs to a device and method for chemical separation process, and relates to a refining method of coking crude phenol, specifically a continuous rectification and separation device and method for coking crude phenol. Background technique [0002] Coking phenols are one of the main chemical products extracted from coal tar. The composition and yield of each crude phenol raw material are related to the coal blending composition, coal blending properties and the conditions of coal coke operation. On the one hand, its source comes from coal tar fractionation The phenol oil fraction produced in the coal gasification process, on the other hand, comes from the phenolic compounds extracted from the phenol-containing wastewater produced in the coal gasification process. The crude phenolic components of the two sources basically contain phenol, o-cresol, and m-p-cresol , water, xylenol, higher phenol and its asphalt and other impurities. [0003...

AI Technical Summary

Problems solved by technology

Among them, Chinese patent CN1279231A discloses a refining method of sulfur-containing crude phenol, which is to add NaOH or KOH solution and hydrogen peroxide for alkalization and oxidation treatment, but this process is mainly developed for crude phenol in petroleum light oil, and For coked crude phenol with more complex components, there are disadvantages such as long treatment period, poor decolorization and deodorization effects, etc., obviously not suitable for pretreatment of coked crude phenol

[0005] Japanese patent JP62-12731 uses the method of hydrogen peroxide and clay refining to pretreat crude phenol, which can convert the mercaptan and other compounds of the raw material into disulfides with less odor and then obtain refined crude phenol by refining with clay. Experiments show that, This kind of pretreatment has good deodorization and desulfurization effects, but its decolorization effect is very poor, and the product quality after refining crude phenol is quite unstable, which seriously affects the refining effect and recovery value of coked crude phenol

[0006] Since the total amount of raw materials of phenolic fractions accounts for a relatively small proportion of coal tar, usually 1 million tons / year coking enterprises only produce about 1-1.2% of crude phenol raw materials, while the early domestic coking enterprises are all below 1 million tons / year scale, the total amount of crude phenol raw materials is relatively small and basically below 10,000 tons / year, so domestic and foreign related enterprises adopt batch-type vacuum distillation technology with simple equipment and less investment, that is, two Tower or three-tower batch distillation tower device and process to complete several processes such as slag removal, dehydration, phenol refining and cresol refining, so as to realize the recovery of phenol and cresol and other products. As we all know, due to the process characteristics of batch distillation and its phenol Due to the heat-sensitive characteristics of phenolic compounds, there must be phenomena such as decomposition and carbon formation of phenolic compounds in the batch distillation separation process, which will affect the quality and yield of the product, so that the stability of the product quality of the entire process is poor. In the process of distillation treatment, there are too many transitional fractions between the components, which requires repeated rectification, which also results in a large energy consumption in the entire separation process. Obviously, from the perspective of process reliability and economy, the device for the separation of crude phenol by batch rectification And its technology is no longer suitable for large-scale treatment of coking crude phenol.

Images