| The biological scouring of ramie using enzymes was reported in this thesis. The convenient and cheap method of ramie scouring was explored in order to enhance the level of production and protect environment. It was discussed that the optimal qualification of bacteria using in the ramie scouring and the classification of these bacteria and their enzymes. The characteristics of ramie's scouring were summarized including the bacteria selecting, cultivating, biological scouring and the scouring process of hydroxide's supplement. Using selecting medium, 800 kinds of bacteria were detected from different regions, sludge, soil and waster water and 320 strains were alive in alkaline condition. Among them, only three kinds of alkaline bacteria (B3, B6 and B7) showed the ability of ramie scouring. These bacteria were preliminarily identified and their enzyme characteristics were analyzed. The technological process of the alkaline bacteria scouring, other assistant conditions on biological scouring and the technological process of hydroxide's scouring were investigated. The characteristics of ramie having biological scouring and BOD, COD in the scouring waste through biological scouring were also discussed. It was found that this procedure was easy, convenient and practical. The preliminary remaining rate was 9% by the bacteria scouring that was much better than other scouring ways. The remaining jelly's rate was further decreased to 1% boiled by adding lower concentration of hydroxide (only 0.6% NaOH). It was proved to be satisfied to the demand of yarning.The results showed: 1) 320 kinds of bacteria of 800 kinds from different dirt, soil and sewage could grow in the alkaline conditions, and only three kinds of bacteria (B3, B6 and B7) selected from the medium of ramie showed the better effect of scouring. The remaining rates of B3, B6, and B7 were respectively 14.3%, 12.1%, 13.9%, and B6 was the best. The three bacteria were preliminarily designated as the Bacillus alcalophilus. 2) The enzyme characteristics of the alkaline bacteria were described: they were not able to decompound the aceticMASTER'S THESISmethyl-cellulose, but B6 showed the activity of pectinase (3710 U/ml after two days). After B6 was cultivated in hemicellulose or ramie nutrition mediums for one day, the hemicellulose's activity were 105 U/ml and 90 U/ml respectively. It was found that B6 cultivated in ramie nutrition medium could reduce the concentration of lignin from 0.96% to 0.62%. 3) The optimal process conditions, i.e. 10% inoculums ratio, 24 hours, pH 10, 40ç™±, were determined by the normal cross's method. The rate of remaining jelly was 10.2%. After ramie pretreated mechanically and then scoured for 20 hours, and the scouring rate was more 4% than the control. The remaining jelly rate was decreased 1.2% and 1% respectively by agitation and by the addition of EDTA and buffer. The equality and quantity of initial ramie didn't affect the scouring percentage. To satisfy the yarning demand, hydroxides could be used to further scour. The concentration of hydroxides was only 0.6% NaOH and the remaining jelly's rate was 0.85%. 4) The ramie's characteristics after scouring: The strength of single fiber was much more 0.15% than that of the usual ramie scoured (0.57%). The crystallinity index was 0.85, which was 0.08 much more than the method of scoured with chemistry. When ramie was dyed for 30 min with 1% active colorful red dyestuff (owf), the exhaustion of dyes by biological scouring was much more 15% than that by chemical scouring. BOD and COD in the biological waste liquid were respectively lower 150-200mg/L, 400-600mg/L than that in the chemical waste liquid. In the biological scouring pH was 7-8, while in chemical one pH was 9-11.5.The results indicated: that the alkaline bacteria come from nature and could be obtained easily. These bacteria can live in alkaline conditions and use in the ramie's scouring demands. The three bacteria didn't produce cellulosease, although they created pectinase, hemicellulase and ligninase. The biologi...
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