Cotton yarn refining and dyeing one-bath method

The invention relates to a cotton yarn refining and dyeing one-bath method. According to the present invention, a pre-alkali addition method and a dye stabilizer are adopted, such that contradiction between refining and dyeing is effectively solved, refining and dyeing one-bath is achieved, a color fixation rate is not reduced or less reduced, and light, medium and dark fabrics can be dyed; the method has characteristics of process shortening, water, steam, electricity and coal saving, water washing step reduction, wastewater emission reduction, and COD emission reduction; the method further has characteristics of simple operation and easy production; the dyeing process comprises: adding a refining and dyeing one-bath refining agent, a stabilizer, mirabilitum dehydratum or gravy salt, an active dye, and a color fixation alkali, carrying out medium temperature (60-70 DEG C) dyeing, high temperature (80-90 DEG C) dyeing and refining (95-98 DEG C), soaping, carrying out water washing, carrying out color fixation