Patent ID: 7645358
Filing Date: 2010-01-12
Classification: C12P,D21C,Y02W

Abstract:
1. A process for the biological deinking of paper printed with non-impact and non-dispersible ink, the said process comprising: (a) growing coccoid bacterial isolate in a nutrient broth containing beef extract, peptic digest of animal tissue in salinated water with salinity ranging from approximately 30 to approximately 35 parts per thousand for at least approximately 4 days; (b) adding the resulting biomass of step (a) at approximately 20% concentration to inoculate paper pulp diluted to at least approximately 6% consistency suspended in salinated water having a salinity of approximately 15 parts per thousand; (c) incubating the inoculated pulp for a minimum period of approximately 96hours followed by diluting the pulp approximately tenfold; (d) adding approximately 1% by weight of a surfactant and aerating for at least approximately 10 minutes with compressed air to let the stray residual ink particles and contaminants to flow out of the container; and (e) filtering the pulp of step (d) over a funnel under suction, to get a sheet of deinked pulp with uniform thickness and reading its brightness by radiance measurement.