Alkyl polyglycosides have received extensive attention worldwide

2017-11-21 11:01:45

For example, in deinking by washing, chemicals such as sodium hydroxide, water glass, hydrogen peroxide and nonionic surfactants have a pH of 9 to 11 during deinking; in flotation deinking, various fatty acids are trapped. The concentration agent is carried out under the condition that calcium ions are involved, and the pH value in this process can be as high as 11-12. With the development of printing technology, the quality of recycled paper and the requirements of environmental protection, the disadvantages of alkaline deinking are becoming more and more obvious. For example, the COD of wastewater is high, and the ground wood pulp is easily alkaline and black. A very promising and promising method of deinking - neutral deinking.

Deinking mechanism of neutral deinking

1) Neutral deinking is similar to alkalinity, that is, the surfactant is absorbed by the surface. Due to the decrease of the surface tension of the interface, the surfactant penetrates into the interface between the ink and the fiber, and is removed under the dual action of mechanical washing and surface vigor. Ink

2) Under neutral conditions, more ink is selectively dispersed to achieve the desired particle size for good flotation and washing results without excessive dispersion;

3) Since the neutral environment allows the agglomeration of the adhesive material and mechanical removal, the adhesive impurities are reduced;

4) Under neutral conditions, the amount of pH adjuster can be eliminated or reduced, which can reduce the fluctuation of the drainage performance of the slurry fed to the paper machine, and the PH change is less, resulting in better running performance of the paper machine.

Bio-deinking agent is a high-efficiency compound enzyme preparation, which can be used for deinking of various waste papers. Because of its low pollution, high activity and good deinking effect, alkyl polyglucosides have received extensive attention in the world in recent years. . Enzyme-treated waste paper technology has at least the following advantages over conventional chemical deinking technology:

1) The removal rate of high ink (and viscose) increases the whiteness of waste paper pulp;

2) high pulp yield and reduced ash;

3) Improve the physical properties of waste paper pulp (such as water filtration) without negatively affecting pulp strength;

4) Reduce the BOD and COD of wastewater in the waste paper treatment process, greatly reducing the amount of chemicals used in deinking and wastewater treatment;

5) It is particularly effective for deinking mixed office waste paper that is difficult to be conventionally floated and deinked.