Separation purification method and apparatus for p-benzene dicarboxylic acid

A technology of terephthalic acid and filter cake is applied in the field of separation and purification of compounds, which can solve the problems of large investment and energy consumption, high equipment investment and high maintenance cost, and achieves low equipment investment cost, low energy consumption and product quality assurance. Effect

Active Publication Date: 2008-12-10
CHINA KUNLUN CONTRACTING & ENG
View PDF1 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The problem with this method is that the decanter pressure centrifuge is a high-speed rotating device (generally, the speed is ~3000RPM), with many faults, fragile seals, high maintenance costs, large investment and energy consumption
This process can ensure the washing effect of crude terephthalic acid, but the equipment investment is relatively high

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Separation purification method and apparatus for p-benzene dicarboxylic acid
  • Separation purification method and apparatus for p-benzene dicarboxylic acid

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0051] As shown in Figures 1 and 2, the solid phase content from the fourth crystallizer is ~36.5%, the viscosity is ~0.7cp, the p-TA content is ~1330ppm, the average diameter of TA particles is 110~120μm, and the pressure is 0.35MPaG , and the CTA slurry with a temperature of about 148°C was pressurized to 0.55MPaG with a pump, and then fed into the filtration zone of the rotary pressure filter. The pressure drop on both sides of the filter cloth in the filter area is maintained at about 0.15MPaG. A filter cake with a thickness of ~120mm is gradually formed in the filter zone, and the filtrate enters the filtrate tank with the same temperature and pressure as the fourth crystallizer through the conduit, and the filtrate is sent to the PTA mother liquor recovery system under liquid level control.

[0052] Inside the rotary pressure filter, the formed filter cake is transferred to the dehumidification zone by the rotation of the drum, in N 2 Dry and dehumidify under air, the a...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a method for separating and purifying a terephthalic acid, comprising the following steps of: (a) filtering a pulp containing crystalline terephthalic acid with a rotary pressure filter; (b) repulping a filter cake obtained in the step (a) into a pulp again; and (c) filtering a pulp obtained from the step (b) with a rotary vacuum filter. The invention also provides a system for carrying out the method, comprising the rotary pressure filter, a repulpator, and the rotary vacuum filter, which are connected sequentially along the flow direction of a material flow.

Description

technical field [0001] The invention relates to a method for separating and purifying compounds, in particular to a method for separating and purifying terephthalic acid. Background technique [0002] Purified terephthalic acid (PTA) is one of the important raw materials for the production of polyester (PET). With the rapid development of the PET industry, the demand for PTA is also increasing rapidly. At present, the commonly used production method of terephthalic acid (TA) is to oxidize and crystallize p-xylene to produce crude terephthalic acid (CTA) containing a large amount of impurities, and then dissolve CTA in water under high temperature and pressure, Hydrofining is carried out under the action of a catalyst, so that the original water-insoluble impurities are dissolved in water, and then the slurry is subjected to cooling and pressure-lowering crystallization and separation and purification to obtain the final purified terephthalic acid (PTA). [0003] PTA separa...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C07C63/26C07C51/42
Inventor 罗文德周华堂姚瑞奎张莼陈燕玲李利军
Owner CHINA KUNLUN CONTRACTING & ENG
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products