Effluent improvement by source reduction of chemicals used in textile printing

SOURCE REDUCTION OF CHEMICALS IN TEXTILE PRINTING This is a wide-ranging subject that is now becoming of increasing importance. Allprintersare aware of thegreater pressure being placed on them by both national and local government legislation on the environment. This legislation is aimed at reducing emission from flues and controlling and monitoring the discharge of effluents. In the past the textile printer essentially took the view that any addition of a chemical, e.g. urea to assist in producing a smoother and more level print, should be made; how that might subsequently affect the effluent was a secondary matter. This attitude is now changing, and textile printers and the dyestuff suppliers are actively examining chemical, dyestuff and machinery approaches to the problem of reducing chemicals at their source. In the case of printing this essentially means radically reassessing current print recipes and process methods. Figure 1 highlights the major issues now facing the printer (the list is by no means complete). For a fuller review of the area the excellent papers by Smith should be consulted [l]. These issues are grouped under four general headings below.