Method for dyeing yarn with dyeing wastewater

The invention belongs to the technical field of textile printing and dyeing, and particularly relates to a method for dyeing yarn by using dyeing wastewater. The method comprises the steps that the pHvalue of the dyeing wastewater is adjusted, then reactive dyes are added to obtain a mixed dyeing solution, and the yarn is dyed with the mixed dyeing solution, wherein the dyeing wastewater is two or three kinds of pure cotton dyeing wastewater, polyester dyeing wastewater or chinlon dyeing wastewater, and the yarn is yarn that can be dyed by the reactive dyes. According to the method, the dyeing wastewater is directly used for dyeing without using sewage treatment methods such as flocculation, decoloration and the like, so that bleaching and dyeing water is reduced, the production cost is reduced, and environment-friendly and energy-saving production is realized. 本发明属于纺织印染技术领域，具体涉及一种用染色废水对纱线进行染色的方法。染色废水调节pH值后加入活性染料得到混合染液，混合染液对纱线进行染色；其中，染色废水为纯棉染色废水、涤纶染色废水或锦纶染色废水中的两种或三种，纱线为活性染料能够上染的纱线。本发明染色废水不需使用絮凝、脱色等污水处理手法直接用于染