SYSTEMS AND PROCESSES FOR MAKING A POLY(VINYL ACETAL) RESIN WITH ENHANCED PARTICLE TRANSPORT AND RECOVERY

摘要

Processes and systems for making a poly(vinyl acetal) resin particles are provided. The processes and systems described herein utilize one or more methods, including, for example, slurry dilution and/or filtration of various process streams, to optimize the transport and recovery of the poly(vinyl acetal) resin particles. Systems and processes described herein facilitate increased production of the final resin product by minimizing product loss and maximizing on-line operation time and production flexibility.

主权项

1. A process for producing a poly(vinyl acetal) resin, said process comprising:
(a) reacting a poly(vinyl alcohol) with at least one aldehyde to produce a reaction slurry comprising a plurality of poly(vinyl acetal) resin particles; (b) contacting at least a portion of said poly(vinyl acetal) resin particles with a wash liquid to thereby provide a plurality of washed particles and a spent wash liquid; (c) withdrawing at least a portion of said washed particles and spent wash liquid from said wash vessel as a solids-containing slurry; (d) passing a portion of said solids-containing slurry through at least one filtration device to thereby provide a solids-enriched retentate stream and a solids-depleted permeate stream, wherein said passing increases the concentration of solids in said solids-enriched retentate stream as compared to the solids content of said solids-containing slurry introduced into said filtration device; and (d) reintroducing at least a portion of said solids-enriched retentate stream back into said process at a location at or downstream of said contacting step.