Patent · US Expired

Method for the preparation of spherical microorganism cell aggregates

US4543332A · kind A · utility

55Cited by
2References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 24, 1983
Grant dateSep 24, 1985
Priority date
Expiry dateFeb 24, 2003

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC12N11/02
  • WIPO fieldBiotechnology
  • WIPO sectorChemistry

Abstract

Spherically shaped bacterial cell aggregates are produced by spheronizing extruded flocculated cells. The cells are flocculated from aqueous medium with a cross-linked polyamine which is the reaction product of an epihalohydrin/polyamine copolymer and a cross-linking agent. Prior to being extruded, a filter cake having 68 to 76 weight percent water is produced by filtration of the flocculated cells, and the filter cake is ground into particles no greater than 60 mesh. Spheronizing is with a plate rotating at a tangential velocity of 4.5 to 12 meters per second within a cylinder containing the plate. Toughness of the spherical aggregates produced can be increased by the addition of a binder after filtration and before extrusion. During spheronizing, fines may be produced. These fines can be recycled by mixing them with the wet filter cake and binder before extrusion.

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