Case Study 01
Textile Wastewater Decolorization
Challenge
A textile dyeing facility processing reactive dyes experienced persistent wastewater color and inconsistent clarification. The existing alum treatment required a dosage of 300 mg/L, yet residual color frequently reached 150–200 Pt-Co, making it difficult to maintain consistent effluent quality.
Solution
The treatment program was changed from alum to 31% polyaluminum chloride (PAC), supported by anionic polyacrylamide (PAM).
Jar tests identified a PAC dosage of 150 mg/L at approximately pH 6.5 as the preferred condition. The reported operating program used 1.2 mg/L anionic PAM and adjusted coagulation pH to 6.0–6.8.
Results
The reported results of the optimized program:
COLOR REMOVAL
92%
450 → 36 Pt-Co
COD REMOVAL
72.4%
780 → 215 mg/L
CHEMICAL DOSAGE
−50%
Alum 300 → PAC 150 mg/L
OPERATING COST
−33%
Published treatment-cost comparison