Dyeing and printing houses
Polish colour and COD before discharge or reuse.
- Cotton and blends
- Synthetics
- Denim washing
RESEARCH PARTNERSHIP / 06
Developed withInstitute of Chemical Technology, MumbaiIndia's chemical technology institute since 1933
Validated in trialsDelivered by Rispri Labs
Dye effluent treatment.
COD and colour, gone fast.
Rispri Labs delivers advanced treatment for textile and dye effluent, developed with ICT Mumbai: a reusable graphene catalyst that breaks down dye molecules in minutes and selective polymer adsorbents that capture what remains.
RESEARCH TO REALITYRispri Labs × ICT Mumbai
ICT Mumbai
What it means for you
Dye effluent cleared in 30 minutes.
30 minutes
to cut COD in dye effluent by over 80%.
10 times
the same catalyst is reused after a simple wash.
95%
of dye captured by the polymer polish in about an hour.
Performance
Built for the hardest effluent.
Reactive and acid dyes resist biological treatment, leaving COD and colour above discharge limits. Catalytic oxidation and selective adsorption attack the dye molecule directly.
- 83%
- COD reduction in 30 minutes on dye-laden water
- 10cycles
- Catalyst reuse after peroxide regeneration
- 95%
- Dye removed by polymer adsorbent in 70 minutes
- 189mg/g
- Dye uptake capacity of the adsorbent
Figures are from the research team's controlled trials. Performance on your stream is confirmed in our laboratory before design.
Challenge and response
The problems this solves.
- 01The challenge
Dyes pass through biological treatment, leaving colour in the outlet.
How we solve itA graphene catalyst oxidises the dye molecule itself.
- 02The challenge
COD stays above discharge limits after secondary treatment.
How we solve itCatalytic polishing cuts COD by over 80% in 30 minutes.
- 03The challenge
Activated carbon and chemicals are used once and thrown away.
How we solve itCatalyst and adsorbent are regenerated and reused.
- 04The challenge
Dye residues foul RO membranes in ZLD plants.
How we solve itRemove colour before the RO stage to protect membranes.
How it works
The process, step by step.
- 1
Dose
Graphene-oxide catalyst is added to secondary-treated effluent.
- 2
Oxidise
Dye molecules break down within minutes, cutting COD and colour.
- 3
Polish
A porous organic polymer adsorbs remaining dye selectively.
- 4
Regenerate
Catalyst is regenerated with peroxide; adsorbent is cycled for reuse.
Use cases
Where textile and dye effluent treatment delivers.
Dye and pigment manufacture
Treat concentrated dye-laden streams.
- Dye intermediates
- Pigment units
- Speciality chemicals
Common effluent treatment plants
Add a tertiary stage for textile clusters.
- Textile clusters
- Industrial estates
- Process houses
RO and ZLD protection
Remove colour before membranes.
- Lower membrane fouling
- Longer cleaning intervals
- Cleaner reject
Water reuse in dyeing
Return clear water to the process.
- Rinse water
- Process make-up
- Washing
Multi-product units
Handle changing dye mixes between batches.
- Batch dye houses
- Job-work units
- Garment washers
Comparison
How it compares.
| Factor | Conventional tertiary treatment | Rispri solution |
|---|---|---|
| Colour removal | Coagulants and carbon, often partial | Dye molecule broken down catalytically |
| Speed | Long contact times | Over 80% COD cut in 30 minutes |
| Reuse | Single-use carbon and chemicals | Catalyst reused 10 times; adsorbent cycled |
| Sludge | Chemical sludge from coagulation | Little added sludge |
| Dye range | Varies by chemistry | Methylene blue, brilliant green, Acid Orange II and mixtures |
Standards and regulations
Designed around the rules that apply to you.
We design each system to meet your consent conditions and the regulations for your sector, and our laboratory reports against them.
- Environment (Protection) Rules, 1986Textile and dye industry discharge standards.
- CPCB ZLD guidanceZero liquid discharge expectations for textile clusters.
- State consent conditionsColour, COD and volume limits for each unit.
- Hazardous and Other Wastes Rules, 2016Handling of spent treatment media and sludge.
Industries served
Built for the sectors that need it most.
- Textiles and dyeing
- Dyes and pigments
- Common effluent treatment plants
- Paper and printing
- ETP, STP and ZLD plants
- Water treatment chemicals
Why Rispri
Institute science. Industrial delivery.
Institute-developed technology
Built on patented and peer-reviewed research from our partnership with ICT Mumbai.
Tested on your stream
Our accredited laboratory characterises your water or waste before design and verifies results after.
Engineering since 1999
The team that builds ETPs, STPs and ZLD plants across India takes each solution from pilot to full scale.
One accountable partner
Design, supply, installation, commissioning, operation and testing under one contract.
Questions
Frequently asked questions.
Which dyes does it work on?
Trials covered methylene blue, brilliant green, Acid Orange II and dye mixtures. We test your own effluent in our laboratory before design.
How fast is the treatment?
The graphene catalyst cut COD by up to 82.56% in 30 minutes, and the polymer adsorbent removed about 95% of dye in 70 minutes.
Can the catalyst be reused?
Yes. It was reused 10 times after simple peroxide regeneration.
Where does it fit in my ETP?
As a tertiary polishing stage after biological treatment, or ahead of RO in a ZLD plant to protect the membranes.
How ready is the technology?
It has been validated in controlled trials. We take it to your site through a pilot on your own effluent.
Research partnerships
More solutions from our partnerships.
THE NEXT STEP
Prove it on
your own stream.
Send us a sample or tell us about your site. We will test it, recommend a configuration and set up a pilot.
Request a pilot