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) contacting a particle slurry comprising a plurality of poly(vinyl acetal) resin particles with a wash liquid in at least one wash vessel to thereby provide a plurality of washed poly(vinyl acetal) resin particles and a liquid phase comprising at least a portion of said wash liquid; (b) passing a portion of said liquid phase through at least one cross-flow filter element disposed within the interior of said wash vessel to provide a solids-depleted permeate phase, wherein said permeate phase comprises a lower concentration of said poly(vinyl acetal) resin particles than said particle slurry; (c) removing at least a portion of said permeate phase from said wash vessel as a spent wash liquid stream; and (d) recovering at least a portion of said washed poly(vinyl acetal) resin particles remaining in said wash vessel in a downstream recovery zone, wherein said contacting is carried out in a batch mode or in a single wash vessel.