Lateral line rectification separation method for organic components of polyethylene glycol, ethylene glycol and ethylene glycol monomethyl ether in crystalline silicon cutting mixing recovery liquid

Abstract

The invention provides a lateral line rectification separation method for organic components of polyethylene glycol, ethylene glycol and ethylene glycol monomethyl ether in crystalline silicon cutting mixing recovery liquid, which comprises the following steps of: (1) taking moisture-free crystalline silicon cutting mixing recovery liquid as raw material, and pumping into a lateral line fractionating tower; (2) carrying out fraction at 124-125 DEG C in a cutting way on the top of the tower, controlling reflux ratio, and recovering an ethylene glycol monomethyl ether product from the top of the tower to enter into an ethylene glycol monomethyl ether storing tank; (3) carrying out fraction at 195-200 DEG C in a cutting way at the lateral line on the upper part of the tower, exchanging heat by a heat exchanger to be taken as an ethylene glycol product to enter into a storing tank; and (4) reheating material on a tower kettle by a reboiler, controlling the temperature to be in a range of 240 DEG C to 245 DEG C, cooling some material to be taken as a polyethylene glycol product to enter into a polyethylene glycol product storing tank. The method adopts optimized technology parameters, and adopts the lateral line of a single tower to separate three components in the crystalline silicon cutting mixing recovery liquid in a rectifying way. The ethylene glycol monomethyl ether is recovered from the top of the tower, the ethylene glycol is recovered from the lateral line, and the polyethylene glycol is obtained from the tower kettle. Due to single-tower operation, the equipment cost and the energy consumption can be reduced compared with those of the conventional method.

Description

technical field [0001] The invention relates to a chemical separation method, in particular to a side line rectification separation method of organic components polyethylene glycol, ethylene glycol and ethylene glycol monomethyl ether in the crystal silicon cutting mixed recovery liquid. Background technique [0002] Wafer dicing is a critical part of the solar photovoltaic cell manufacturing process. This process is used to process solid silicon ingots of monocrystalline or polycrystalline silicon. The wire saw first cuts the silicon ingot into cubes and then into very thin wafers. Due to the strict requirements on the flatness, cleanliness, conductivity and other performance indicators of the solar silicon wafer surface in application, it is necessary to use silicon carbide micropowder with high hardness, small particle size and concentrated particle size distribution during the cutting process of solar silicon wafers. as the main cutting medium. In order to disperse th...

AI Technical Summary

Problems solved by technology

[0004] The disadvantages of two-tower atmospheric distillation mainly lie in two aspects. One is that the two-tower process requires higher equipment and operating costs, and the other is that the energy consumption is relatively large due to two evaporations.

This also directly affects the cost of recycling and regeneration of crystalline silicon cutting fluid

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