Biological enzyme deinking method for waste paper

Abstract

Provided is a biological enzyme deinking method for waste paper, in which flotation applies polyoxyethylene alkyl ether as flotation auxiliary, deinking process applies compound enzyme as deinking agent. The method improves the white content of the regenerated pulp by chemistry method, which is enhanced to 5-8% higher, and the COD value of the discharged sewage reduced more than 60%. The paper pulp filtration performance is further increased and the strength is similar, thus it can meet requirement of making different papers.

Description

technical field [0001] The invention belongs to the improvement of waste paper deinking technology in pulping and papermaking, and relates to the application technical field of biotechnology in pulping and papermaking. Background technique [0002] At present, the traditional waste paper deinking technology adopts the alkaline chemical deinking method, the biggest drawback is the high chemical oxygen demand (COD value) of the discharged sewage, serious pollution, and the recycled secondary fiber is of poor quality and cannot be used. Require. In recent years, with the rapid development of papermaking technology and printing ink technology, the chemical deinking method has encountered an unsolvable problem: the non-contact waste paper (electrostatic copy and laser printing paper) that accounts for more than 80% of office waste paper. The ink uses a special thermoplastic synthetic resin as the binder. After curing, it becomes a solid body structure due to crosslinking, and th...

AI Technical Summary

Problems solved by technology

Due to the singleness of the selected enzyme preparation and process problems, its economic cost and secondary fiber quality cannot meet the ideal requirements

T.W.Jeffries, et al, Tappi J., 1994, 77 (4): 173-179 reported the enzymatic deinking technology of xerographic copying and laser printing paper, and the cleanliness of recycled pulp obtained by simple hemicellulase deinking not tall

A Chinese patent discloses "A Process for Regenerating Waste Paper Using Biological Deinking" (Application No.: CN97101654). Improve 21.2% (old newspaper) and 2.9% (old office waste paper), but do not disclose to enzyme dosage in this patent document, and selected enzyme preparation still needs to add surfactant when office waste paper deinking, this must Will increase the COD value of discharged sewage

Chinese patent (application number: CN99120426) discloses "a production method for deinking waste paper by enzymatic method", which uses a single crude cellulase to treat waste newsprint, and the disclosure of the specific process and treatment effect is very limited.