Application Of Biomaterials In The Treatment Of Dyeing And Printing Wastewater

The dyeing and printing wastewater was produced by the textile manufacturing procedures including pretreatment, dyeing, printing and finishing of fabrics. The wastewater had the characteristics comprising large emissions, low water quality, low biodegradability, high COD value. There are three ways to handle the wastewater including physical chemical methods, chemical methods and biological chemical methods, and each method has its advantages and disadvantages. As we know, biomaterials have special chemical, physical and biological functions, and the source for the materials is very vast. Sometimes, the biomaterials were thrown away as a waste. So, the application of biomaterial in wastewater treatment was the way to reuse of the materials, which can save the resources and energy. In this paper, three biomaterials(chitosan, silkworm chrysalis powder and rice bran powder) were used to adsorb the dyeing in the wastewater. Three different kinds of dyeing including reactive disperse and acid dyes were used to simulate the wastewater getting the dyeing and finishing factory. The influences of adsorbent concentration, dye concentration, pH value of the solution and adsorption time were discussed to optimize the process. As shown in the experimental results, the biomaterials of chitosan and silkworm chrysalis powder had excellent adsorption capacity to the reactive and acid dyes, while the adsorption capacity to the disperse dyes was relatively low due to the structure of disperse dyes. The adsorption time can be controlled between 40 to 60 mins, while the pH value of the solution can influence the structure of the biomaterials. In general, the adsorption effect is better under acidic conditions.