Study On Scouring Of Flax Roves With Pseudomonas SP DA10 And Their Enzymes

Linen textiles are preferred by most consumers because of their excellent features such as fast moisture absorption and carry-off, antibacteria, straight figure, comfortable feeling and so on. At present, the manufacture of high-end linen yarns requires a unique treatment process, comprising alkaline scouring and bleaching of flax roves followed by wet-spinning on highly specialized machinery. The purpose of chemical treatments of flax roves is to remove part of gummy materials among fibers, and improve the degree of separation and spinnability of flax fibers. However, alkaline scouring and bleaching of flax roves can cause severe environmental pollution, great fiber loss and high water and energy consumption.Nowadays, some researchers began to utilize different commercial enzymes to scour flax roves. But there were still some problems of technical process existing in the enzymes based combined scouring and high price of enzymes restricted application and promotion of enzymes in large scale. In contrast, bacteria degumming process involving polysaccharide degrading microorganisms and their enzymes has been applied deeply in degumming of decorticated ramie and retting of raw flax.In the study, scouring flax roves with Pseudomonas sp DA 10 and their enzymes was studied, which was directed at conventional alkaline scouring and semi-bleaching process. The use level of alkali in the scouring of flax roves were lowered in order to reduce alkaline effluent and fiber loss with the aid of degumming bacterium and their enzymes.Specific researches as follows:(1)Study of bacterial scouring of flax roves by using bacterium DA 10 and their enzymes was carried out. Dosage of the fermentation beer, initial pH, temperature and treatment time were selected to get better scouring performance;(2)A simple and effective scheme of combined scouring of flax roves was selected. The alkali-bacteria combined scouring and bacteria-alkali combined scouring were mainly optimized and discussed;(3)The selected scheme of combined scouring and conventional alkali boiling were discussed in terms of fiber bundles strength, fiber fineness and percentage of weight loss of treated fibers;(4)A effective scheme of combined scouring and bleaching of flax roves was selected and then was compared with conventional semi-bleaching process in terms of fiber bundles strength, fiber fineness, whiteness and percentage of weight loss of treated fibers;(5)Some typical schemes of combined scouring and combined scouring and bleaching of flax roves were chosen. Pilot plant-roving treatments were carried out in Golden Eagle Co.,Ltd and treated roves were wet-spun to assess feasibility of those schemes.Specific Researches above were conducted and then experimental data gained provided an important foundation for further applications of bacterium DA 10 in flax roves scouring. The study found as follows:(1)Scouring flax roves with bacterium DA 10 and their enzymes was mild which resulted in less fiber loss. When the roves were treated with polysaccharide-degrading enzymes from bacterium DA 10 alone, it was found that gummy materials on the surface of fibers could be removed greatly via long time treatment. Besides, conditions of bacterial scouring of flax roves were not very strict which made bacterium DA 10 feasible for practical application;(2)Compared with bacteria scouring alone, fiber fineness and strength of fibers treated by pretreatment-bacteria combined scouring were improved. Among the combined scouring, quality of flax fibers treated with alkali-bacteria combined scouring was best;.(3)Fiber fineness and strength of fibers treated by bacteria-alkali combined scouring were also improved in comparison with bacteria scouring alone, but still inferior to those of alkali-bacteria combined scouring;(4)Compared with conventional alkali boiling, percentage of weight loss of the fibers caused by the combined scouring and use level of alkali were significantly lower but the performance of the scouring was still similar to that of conventional scouring;(5)Flax roves treated by bacteria scouring alone were bleached with peroxide hydrogen and compared with those of conventional semi-bleaching process. Percentage of weight loss of treated fibers of the combined scouring and bleaching were significantly lower than those of semi-bleaching. However, quality of flax fibers treated with combined scouring and bleaching was not as good as that of semi-bleaching.(6)Results of pilot plant-roving treatments and wet-spinning in Golden Eagle Co.,Ltd indicated that some selected schemes were feasible though quality of the bacterial flax yarn was not as excellent as that of chemical flax yarn.