Method and device for removing trace water in single polycrystalline silicon cutting fluid

Abstract

The invention relates to a method and a device for removing trace water in a single polycrystalline silicon cutting fluid. The method is characterized in that by utilizing a centrifugal pump, the cutting fluid which contains trace water is fed into a drying device with a drying agent therein from a feeding tube; after the cutting fluid sufficiently exchanges with the drying agent in the drying device, the cutting fluid with qualified water content is discharged from a discharge tube; the drying agent is a mixture obtained by mixing a little allochroic silicagel into a molecular sieve or aluminium oxide microspheres; and when the allochroic silicagel is completely changed into red, hot air with a temperature of 120 DEG C is introduced into the drying device for carrying out drying regeneration treatment on the drying agent. The invention has the advantages that the method is simple and convenient, the device is simple, the dehydrating effect is good, the drying agent can be repeatedly used, the energy consumption of enterprises is reduced, and the like.

Description

technical field [0001] The invention belongs to the technical field of chemical industry, and in particular relates to a method and a device for removing trace moisture in single polysilicon cutting fluid. Background technique [0002] During the processing of single and polycrystalline silicon, wire cutting equipment is usually used internationally to cut silicon rods into sheets of different diameters and thicknesses. High-hardness silicon carbide micropowder is used as the main cutting medium in cutting. In order to disperse the silicon carbide micropowder evenly during the cutting process and take away the huge frictional heat generated by cutting in time, it is usually necessary to add silicon carbide micropowder to the cutting fluid in a certain proportion. Among them, it is configured as a uniform, stable and well-dispersed mortar for cutting silicon wafers. [0003] The main component of the cutting fluid is polyethylene glycol. During the online cutting process, th...

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Problems solved by technology

[0005] The moisture content of the cutting fluid is generally less than 0.5%, but because the cutting fluid and water are infinitely miscible, it is very easy to absorb water (the cutting fluid is placed in the air with a humidity of 80% for 12 hours, and the moisture content increases by about 1-3%). In a larger environment, if the storage container of the cutting fluid is not well sealed, the moisture content of the cutting fluid will increase

At present, in the cutting fluid production or recycling enterprises, there is no better and simpler method for the increase of moisture except for re-vacuum distillation. The disadvantages of this are: 1. Vacuum distillation is a dynamic equilibrium process. Under reduced pressure distillation, the main components and components of the recovered liquid will change, thereby affecting the use effect of the cutting fluid; 2. Repeatedly reduced pressure distillation will increase energy consumption and increase the cost of the enterprise