Indonesia Printing & Dyeing Wastewater Decolorizing Agent Case

1. Background & Pain Points

Indonesia has a strong textile and dyeing industry, and many mills face mounting pressure to meet stricter discharge standards for highly colored, high-COD wastewater. With limited budgets for civil works, most plants look for ways to upgrade their existing treatment systems rather than rebuild from scratch.

The customer in this case is a typical Indonesian printing and dyeing factory working mainly with reactive and disperse dyes. It operates a combined physical-chemical and biological treatment plant. As orders increased and regulations became tighter, the existing process frequently struggled with color removal, especially during dark-shade production campaigns. Operators often had to dilute or recycle treated water to maintain acceptable appearance, which reduced overall treatment efficiency.

The customer’s goal was to introduce a high-performance decolorizing agent tailored to printing and dyeing wastewater, improving color removal and stabilizing effluent quality while keeping overall chemical cost under control and avoiding major changes to existing tanks and equipment.

2. Customer Profile & Application Scenario

• Location: Indonesia, textile and dyeing factory within an industrial park;

• Wastewater type: Mixed printing & dyeing wastewater dominated by reactive and disperse dyes, with high color and complex composition;

• Existing process:

  • Pre-treatment and coagulation–sedimentation at the front end;

  • Biological treatment (e.g. contact oxidation) at the back end;

• Main issues:

  • Effluent color fluctuated significantly during deep-shade production;

  • Coagulation alone was not sufficient for color removal, putting stress on the biological stage;

  • Simply increasing conventional coagulant dosage led to higher sludge volumes and rising operating costs.

3. Our Solution (Product + Integration Approach)

To address these challenges, we recommended a high-efficiency decolorizing agent with 50% solid content, designed especially for printing and dyeing wastewater. The key aspects of the solution were:

1. Product characteristics

   • 50% solid content, making the product easier to transport and store and allowing precise dosage control;

   • Formulated for typical dyeing wastewater systems based on reactive and disperse dyes, providing strong decolorization with auxiliary coagulation effects;

   • Compatible with existing coagulants and flocculants so that overall chemical usage can be optimized instead of simply increased.

2. Process integration

   • After reviewing water quality and fluctuation patterns, we suggested adding a dedicated dosing point for the decolorizing agent around the coagulation unit (either before or in combination with the main coagulant);

   • Lab tests and on-site trials were used to define a suitable dosing range and sequence, ensuring that the decolorizing agent could react fully with color-causing components before removal by coagulation–sedimentation;

   • Integration required only a storage tank and dosing system, with no need to modify existing tanks or major mechanical equipment.

3. Economics and operations

   • The high-concentration 50% formulation helps keep per-cubic-meter chemical consumption under tight control;

   • Optimized dosing allows reduction of conventional coagulant usage, balancing decolorization performance with sludge generation and handling costs.

4. Customer Feedback

After a period of on-site dosing and adjustment, the Indonesian customer reported that:

• Effluent color during dark-shade production became much more stable, with fewer “good one day, poor the next” situations;

• While maintaining compliant discharge, the plant was able to cut back on conventional coagulant consumption, which in turn reduced sludge volumes and eased the burden on dewatering and off-site disposal;

• The separate dosing system for the decolorizing agent allows operators to fine-tune dosage visually based on incoming wastewater color, making it easier to link process control with routine field inspections.

Overall, the customer felt that this 50% solid-content decolorizing agent provided a practical upgrade path for the existing wastewater plant—focusing on chemical strategy rather than major civil modifications, and laying a foundation for further optimization of COD, nitrogen and other parameters in the future.

5. Summary

For printing and dyeing plants in Indonesia and other Southeast Asian countries, upgrading existing treatment systems with a high-concentration, application-specific decolorizing agent and a well-designed dosing strategy can significantly improve effluent color stability with limited investment:

• Suitable for wastewater dominated by reactive and disperse dyes with high color;

• Ideal for plants that cannot easily undertake major civil construction but still need better compliance; 

• Creates a platform for future refinement, such as online monitoring and intelligent dosing control.