Tube-type fluid bed reactor in production of chlorothalonil

Abstract

The invention relates to a tube-type fluid bed reactor in the production of chlorothalonil. The fluid bed of the reactor comprises a coil heat exchanger and a tube-type heat exchanger. The coil heat exchanger is arranged below the lower end socket of the fluid bed, and the tube-type heat exchanger is arranged between the coil heat exchanger and the barrel body of the fluid bed. Compared with the prior art, the tube-type fluid bed reactor has the advantages of high temperature, high yield, low cost and the like.

Description

technical field [0001] The invention relates to a production of chlorothalonil, in particular to a tubular fluidized bed reactor in the production of chlorothalonil. Background technique [0002] Tetrachloroisophthalonitrile is obtained by chlorination of isophthalonitrile in a fluidized bed. Tetrachloroisophthalonitrile, the English name is chlorothalonil, and the common name is chlorothalonil. It is a broad-spectrum fungicide with high efficiency and low toxicity. Its main function is to prevent crops from being infected by fungi; Agents, fruit preservatives, fungicides, protective agents for coatings and adhesives. The main reactor of tetrachloroisophthalonitrile is a fluidized bed. Domestic manufacturers use serpentine tubes for heat exchange, especially there is a certain distance between the lower head and the cylinder. The arrangement cannot be uniform, resulting in poor fluidization state, difficult removal of heat, easy breakage of the catalyst, large bed pressure...

AI Technical Summary

Problems solved by technology

The main reactor of tetrachloroisophthalonitrile is a fluidized bed. Domestic manufacturers use serpentine tubes for heat exchange, especially there is a certain distance between the lower head and the cylinder. The arrangement cannot be uniform, resulting in poor fluidization state, difficult removal of heat, easy breakage of the catalyst, large bed pressure drop, resulting in too strong reaction, high reaction temperature locally, and temperature deviation of stream 1, stream 2, and stream 3. 2~5℃, partial overchlorination is easy to occur, and the content of hexachlorobenzene is relatively high. Under normal circumstances, hexachlorobenzene is generally 40~60PPm, which cannot meet the requirements of the international market.

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