A new type of multi-phase flow buffer equipment used after the heat exchanger of the black water system in the coal chemical industry

Abstract

The invention discloses multiphase flow buffering equipment for a heat exchanger of a black water system in the coal chemical industry field. A black water multiphase flow medium containing hard coalpowder particles enters an expanded pipe section through a connecting pipe, a transverse speed component is generated under the flow-guiding effect of an expanded pipe, the medium perpendicular speedis decreased, and shear abrasion of the multiphase flow medium to a straight wall section of a buffering cylinder and impact abrasion of the multiphase flow medium to a flange blind plate at the cylinder bottom are reduced. Nilcra<TM> zirconia can be sprayed to the inner wall of the expanded pipe section, and the abrasion-resistance performance of the inner wall of the expanded pipe section is effectively improved. The black water multiphase flow medium containing the hard coal powder particles flows to a ceramic plate at the cylinder bottom to be deflected and enters a follow-up flash tank device through a buffering cylinder outlet. Nilcra<TM> zirconia ceramic is embedded in the flange blind plate at the cylinder bottom, bottom impact and abrasion resisting performance is enhanced, the overall abrasion-resistant and impact-resistant characteristics of the equipment are effectively improved, and the operation stability and safety of the system are guaranteed practically.

Description

Technical field[0001]The invention relates to a post-valve buffer device used in the field of coal chemical industry with high temperature resistance, wear resistance and impact resistance, in particular to a novel multiphase flow buffer device behind a heat exchanger of a black water system in the field of coal chemical industry.Background technique[0002]In recent years, the domestic coal chemical industry has developed rapidly, and the coal gasification process has been widely used in projects such as coal-to-hydrogen, coal-to-methanol, coal-to-olefin, and coal-to-ammonia. Ningxia, Shandong, Inner Mongolia and other places have successively started the construction of many large-scale coal gasification plants.[0003]The black water system is widely used in the coal chemical industry and is one of the important systems of coal gasification equipment. The transport medium of the system is a gas-liquid-solid multiphase fluid, which contains a large number of solid hard coal particles ...

AI Technical Summary

Problems solved by technology

[0005] According to scientific research, the reasons for the perforation and leakage failure of the rear buffer tube of the heat exchanger mainly include: 1) The density of the black water medium is high (815kg / m 3 ), high flow rate (30-60m / s), high temperature (246°C); 2) The buffer cylinder is made of 316 stainless steel, with poor wear resistance and a wear rate of 1.0e -8 kg / m 2 s; 3) The dimension design of the Venturi expansion part of the buffer tube is unreasonable, and it is easy to form a large impact angle of solid particles, which intensifies the erosion and wear rate; 4) The structure design of the blind plate of the bottom flange is unreasonable

This part is a high-risk area of ​​scouring and wear, and most buffer tubes do not perform local strengthening treatment on the blind flange blind plate at the bottom

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