BWD-01 Cationic Decolorant for Knitwear Reactive Dye Wastewater in Portugal
Product Overview
Textile wet processing in Portugal does not create one uniform wastewater. Fiber type, dye class, shade depth, washing recipe and finishing chemistry can change the color and charge demand from one production batch to the next.
BWD-01 supplies strong cationic charge to destabilize negatively charged soluble dyes and fine color-bearing particles. It is especially relevant to reactive and direct dyes for cotton knit products. The objective is not merely to make the sample look clearer, but to produce flocs that can be separated reliably by sedimentation or dissolved-air flotation.

Textile Wastewater Problem in Portugal
The central treatment problem is that short fashion cycles and varied shade depths create changing residual color and CODcr. Conventional inorganic coagulation may remove suspended solids but leave a visible soluble-color fraction. Operators may then increase coagulant dose, creating more sludge without proportional color improvement.
Why the Problem Occurs
- Reactive dyes that do not fix are released during rinsing and soaping.
- Frequent small and medium batches produce several color transitions each day.
- Softeners and finishing auxiliaries can alter floc formation.
BWD-01 Treatment Solution
Use BWD-01 with shade-family operating ranges and confirm the lowest effective dose that maintains fast clarification.
The selected program should be based on actual wastewater rather than a universal dose. A controlled jar test identifies the point where charge neutralization, floc formation, separation speed and sludge production are balanced. PAC can be tested before or after BWD-01, but the two products must be prepared and dosed separately.
Technical Specifications
| Property | BWD-01 Specification |
| Chemical name | Quaternary ammonium cationic polymer |
| Appearance | Colorless to yellowish translucent liquid |
| Solid content | 50% min |
| Specific gravity at 20 C | 1.1-1.3 |
| pH value, 30% solution | 3-6 |
| Viscosity at 25 C | 30-300 cps |
| Solubility | Soluble with water at any rate |
| Storage temperature | 0-35 C |
| Standard package | 30 kg or 250 kg plastic drum; 1250 kg IBC |
Recommended Application Scenarios
- Cotton knitwear reactive-dye wastewater.
- Garment dyeing and washing effluent.
- Color polishing before discharge or water-reuse treatment.
How BWD-01 Works
- Charge neutralization: cationic groups interact with negatively charged reactive and direct dyes for cotton knit products and colored colloids.
- Destabilization: reduced electrostatic repulsion allows dissolved or finely dispersed color bodies to associate.
- Floc formation: the destabilized contaminants form visible aggregates; PAC may strengthen or densify flocs where testing supports it.
- Solid-liquid separation: the resulting flocs are removed by sedimentation or air flotation, producing clearer treated water.
How to Choose and Test BWD-01
- Divide recipes into light, medium and dark dosage families.
- Recheck the program after major softener changes.
- Compare color removal and sludge dewatering at the same time.
Use untreated and current-treatment controls in every jar-test series. Record raw-water pH, true or apparent color, CODcr, turbidity, temperature and production source. Photographs are useful, but analytical results and sludge behavior are required for a defensible selection.
Recommended Application Procedure
- Collect a representative wastewater sample after appropriate screening and equalization.
- Prepare several BWD-01 working solutions by diluting the product with 10 to 40 times clean water.
- Use pH 7.5-8.0 as the TDS starting range for improved performance, then test nearby values if necessary.
- Dose BWD-01 into the wastewater and mix thoroughly for several minutes.
- Where color and CODcr remain high, test PAC before and after BWD-01 in separate beakers. Do not premix the chemicals.
- Allow the flocs to settle or evaluate them by dissolved-air flotation, matching the site's full-scale process.
- Compare final color, CODcr, turbidity, floc strength, separation time, sludge volume and total treatment cost before scale-up.
Expected Treatment Results
The BWD-01 TDS reports typical decolorization of approximately 50%-99% and CODcr reduction of approximately 50%-80% in suitable applications. These are reference ranges, not guaranteed results. Actual performance depends on dye class, concentration, auxiliaries, pH, mixing, chemical sequence and separation equipment.
Compared with a high-dose inorganic-only program, BWD-01 may provide faster flocculation and settling and may reduce the inorganic contribution to sludge. The comparison should use dry solids, dewatering behavior and disposal cost where sludge reduction is a project objective.
Bluwat Manufacturing Advantages
- Manufacturer since 2000 with more than 25 years of water-treatment chemical production and export experience.
- Three production bases supporting stable supply, batch control and multiple packaging options.
- Products exported to more than 80 countries and used by over 5,000 industrial customers.
- Quality and environmental systems including ISO 9001 and ISO 14001, with ZDHC-conformant BWD product support.
- Routine control of appearance, solid content, specific gravity, pH, viscosity and solubility, supported by batch COA.
- Free sample availability and technical support for jar-test design, dosage comparison and full-scale trial planning.
- Standard BWD-01 packaging in 30 kg and 250 kg plastic drums or 1250 kg IBC containers.
For European textile customers, Bluwat can support batch documentation, COA review, SDS and TDS packages, IBC supply planning, and technical comparison against the plant's current coagulant program.
Frequently Asked Questions
Can shade families simplify dosage control?
Yes. Grouping light, medium and dark shades provides practical starting points. The operator should still verify unusual dyes or auxiliaries.
Does the highest BWD-01 dose always give the best result?
No. Overdosing can waste chemical and may affect floc behavior. Select the lowest dose that meets color, CODcr and separation requirements.
What is the recommended BWD-01 dilution and wastewater pH?
The TDS recommends dilution with 10 to 40 times water and identifies wastewater pH 7.5-8.0 as a useful starting range for better results. The final dilution, pH and dose must be confirmed with the actual effluent.
Can BWD-01 be mixed directly with polyaluminum chloride?
No. BWD-01 and PAC should be prepared and dosed separately. PAC may be added before or after BWD-01 depending on the flocculation test and the treatment process, but the concentrates should not be premixed.
How should the final BWD-01 dosage be selected?
Use a jar test with representative wastewater. Compare color, CODcr, turbidity, floc size, separation time and sludge volume. The best operating dose is the lowest stable dose that meets the plant's complete treatment objective.










