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Traditional printing and dyeing saline pre-treatment dosage, high energy consumption and emissions of large amounts of water pollutants on the environment caused great harm. Enzyme technology because of its high efficiency, saving raw materials and other characteristics, is expected to replace the traditional pre-treatment process, has broad application prospects. In this study, cotton knitted fabric pre-treatment process, carried out enzymatic pretreatment applied research, this technology in the promotion and application of cotton printing and dyeing industry to provide theoretical and technical support to promote cotton printing and dyeing industry, cleaner production and energy savings. Firstly, of the pectinase, cellulase, lipase and protease which nine kinds of enzyme activity of four tests, the influence of temperature, pH and other various types of activity of the enzyme, to determine the optimal use of the single enzyme conditions, and pectin removal, capillary effect, strength loss as a characterization of the fabric scouring effect indicators discussed each single enzyme complex enzyme scouring effect, tests showed alkaline pectinase scouring effect BioPrep3000L far superior to acidic Pectinase PL-300, which added the right amount of cellulase 963 can improve the alkaline pectinase scouring effect, while adding lipase, protease alkaline pectinase scouring effect BioPrp3000L no improvement or even a negative impact. Thus, compound enzyme preparation should be based alkaline pectinase, cellulase supplement. In addition, the response surface (Response Surface Methodology, RSM) analysis optimized enzymatic pretreatment process, the study shows: pH between 8-9, with the changes in pH, pectin removal only minor fluctuations; treatment temperature between 55 ℃ -65 ℃, as the temperature increases, the removal rate decreased pectin, identified by enzyme scouring optimum temperature 55 ℃; pectin removal of the extension of the treatment time and the increase amount of enzyme significantly improved. Minitab 15 responds to the use of software optimization and analysis of various factors on the contribution of pectin removal, combined with cost and production requirements, recommended process is pH 8.5 (1/15 M NaOH / NaH 2 P04), temperature 55 ℃, treatment time 35 min, pectinase 0.03% (owf), cellulose 0.1 g / L, JFC 0.2g / L, bath ratio of 1:20 as the optimal process conditions, after the pilot test pectin Average removal rate was 75.0%, and achieved more satisfactory scouring effect. Secondly, the study of the wetting agent, chelating agent and ionic strength on the enzyme scouring effect, the results showed that: the enzyme scouring penetrant essential, and non-ionic surfactant (JFC) relative to the nonionic surfactant agents have better results; chelating agent (EDTA) contribute to enzyme scouring, when the amount of 0.05 mmol / g substrate, the best effect; ionic strength (K 2 HP04 consumption) increases conducive to the removal of pectin. With the removal of pectin enzyme dosage and treatment time changes relationships, find the function y = αX b pectin removal can be fitted with the variation of the processing time. Enzyme dosage, K 2 HP04 (buffer salts) usage and processing time scouring effect is the impact of three main factors, these three factors through orthogonal test and variance analysis to determine the best application Process conditions: pectinase BioPrep3000L, 0.05% (owf); cellulase 963,0.1 g / L; K2HP042 g / L, treatment time 30 min; pH values ??between 8-9; temperature 55 ℃. The process pectin removal can reach 75%. Finally, a pilot study comparing enzyme treatment technology and traditional alkaline scouring treatment effects, and this process of environmental and economic benefits for analysis. The results showed that enzymatic pretreatment fabric capillary effect, whiteness, pectin removal and dyeing performance with the traditional alkaline treatment process considerably, but the fabric strength loss and weight loss rate was significantly lower, the displacement of traditional alkaline treatment process only 50%, and wastewater improved biodegradability (BOD 5 / COD Cr values ??increased 14.7%), CODcr reduced by 19.7%, water saving effect is obvious. When stained dark cloth enzyme treatment process bleaching step with alkali cooking process and alkali-oxygen - bath process, the cost fell 63.6% and 54.1%; when light-colored cloth dyed with alkali cooking enzymatic bleaching treatment process step by step process more cost down 21.6%, compared with alkali-oxygen - bath process costs are slightly lower. Visible, enzyme treatment process have good economic and social benefits, is a worthy technologies.
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