Extraction device and extraction process

Abstract

The invention provides an extraction device. The extraction device comprises a spray extraction layer and a distillation layer in communication with a liquid outlet of the spray extraction layer; thespray extraction layer comprises a plurality of upper driving rollers at the top, a plurality of lower driving rollers at the bottom, an extraction agent spraying port between the upper driving rollers and the lower driving rollers, a liquid outlet at the bottom, and a film inlet and a film outlet at the top; the distillation layer comprises a heating device at the bottom, an air exhaust port at the top and a liquid discharge port at the bottom. The extraction device has the advantages that spray extraction and instant evaporation methods are applied to extract to-be-treated films; through spray extraction, cross contamination can be avoided, and the stable extraction effect can be achieved; through high-temperature distillation, the liquid storage volume of an extraction tank can be reduced, and the safety can be improved; dichloromethane can be recycled to achieve cyclic utilization, and the consumption of the dichloromethane can be decreased; the extraction device is of a double-layer structure, and accordingly, production / equipment abnormities are handled conveniently.

Description

technical field [0001] The invention belongs to the technical field of extraction, and in particular relates to an extraction equipment and process. Background technique [0002] The wet preparation process of lithium-ion battery diaphragm uses the principle of thermal phase separation to mix and heat polyethylene and small molecule agents, extrude and quench to form a thick polyethylene sheet with microporosity, and then stretch it to make a micron-sized film. Then, through the extraction process, the small molecular agent in the diaphragm is replaced, and then the extraction agent is vaporized after reaching the boiling point at high temperature, and finally the lithium-ion battery diaphragm is prepared. [0003] In the extraction process, the commonly used extractant is dichloromethane, the density of dichloromethane is 1.33g / cm 3 , boiling point 39.8 ℃, highly volatile. The currently used extraction process is immersion extraction, where the diaphragm is immersed in di...

AI Technical Summary

Problems solved by technology

This extraction process has obvious disadvantages: 1. The consumption of dichloromethane is large, 1.0-1.5 tons per day; 2. The storage capacity is large, and the safety guarantee is weak; 3. It is impossible to deal with abnormalities in time, such as the extraction liquid is polluted, the bearing is damaged, etc. , maintenance delays a lot of time

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