Patent · US Expired

Methods and apparatus for removing residual monomers

US6332958A · kind A · utility

7Cited by
7References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 19, 1999
Grant dateDec 25, 2001
Priority date
Expiry dateAug 19, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S203/09
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

An apparatus and a method for removing residual monomers from a slurry containing a polyvinyl chloride. The apparatus has a cylindrical tower with plural perforated plates provided in a vertical direction in the tower, plural chambers formed on the perforated plates serving as their bottom surface, slurry introducing portions provided at two or more of the chambers, flow-down sections provided between the perforated plates to allow the slurry to sequentially flow down from the perforated plate of an upper chamber to the perforated plate of a lower chamber, a steam introducing port at a bottom portion of the tower, a deaerating port at a top portion of the tower, a slurry discharging port at a chamber below a chamber having the slurry introducing port, and hot water ejectors directly under the perforated plates directed at least toward the lower surface of the perforated plates. The apparatus is constructed so that the slurry introducing pipe is connected to a slurry introducing port through an on-off valve and the inside diameter of the slurry introducing pipe is progressively enlarged to 1.2 times or more toward the slurry introducing port.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.