• Home
  • HK Technologies
  • Removal of Indigo Dye in Denim Plant Wastewater by CO2-Capturing Macroalgae

Removal of Indigo Dye in Denim Plant Wastewater by CO2-Capturing Macroalgae

HKRITA
Overview

A biological treatment to remove indigo dye used in denim manufacturing before effluent is discharged into the marine ecosystem; replacing convention method that is high energy and chemical consuming.  

  • Removal of Indigo Dye in Denim Plant Wastewater by CO2-Capturing Macroalgae 0
Technical name of innovation
Removal of Indigo Dye in Denim Plant Wastewater by CO2-Capturing Macroalgae
Research completion
2022
Commercialisation opportunities
Technology licensing
Problem addressed

The indigo used in dyeing jeans is difficult to remove from the wastewater due to the recalcitrant nature of the dye. Meanwhile, current physiochemical decolouring treatment are high energy-consuming and involves uses of chemical additives. Therefore, wastewater treatment of denim dyeing is considered key to maintaining the sustainability of the textile industry.

Innovation
  • This project demonstrates a biological posttreatment method to remove indigo blue in wastewater from denim factories by using sunlight and macroalgae species.
  • The dye in wastewater is broken down to isatin and then simpler compounds by the enzymes produced during the metabolism of the specific macroalgae species for dye biodegradation. Once the chemical structure of indigo dye is broken down, no further decolourisation is needed.
Key impact
  • As a pure biological decolourisation treatment that involves low infrastructure cost while being an effective solution for the reduction of wastewater dye pollutants and its threat to marine ecosystem, it thus contributes towards a sustainable denim manufacturing
Award
  • Silver Medal in the Special Edition 2022 Inventions Geneva Evaluation Days
Application
  • Relieving indigo dye pollution to marine ecosystem
The Hong Kong Research Institute of Textiles and Apparel (HKRITA)

Established in 2006, The Hong Kong Research Institute of Textiles and Apparel (HKRITA) is funded by the Innovation and Technology Commission of the HKSAR government, and hosted by The Hong Kong Polytechnic University. 

HKRITA has achieved research deliverables over the years around our research clusters targeting in sustainability, industry advancement and social benefits through our centre-owned research teams and laboratories as well as collaborations with industry partners and institutions. 

Enquiry