Cut freshwater use and wastewater in textile dyeing
BOSSA Ticaret ve Sanayi İşletmeleri T.A.Ş.
SKD Türkiye总结
A modified warp yarn dyeing process removed the fresh water feed from wash steps, reducing annual water withdrawal by 92% and wastewater by 99% with no new equipment.
Context
Submitted through the COP31 Sustainable Transformation Awards · SKD Türkiye (WBCSD Global Network Partner)
BOSSA Ticaret ve Sanayi İşletmeleri T.A.Ş is a Turkish textile manufacturer with more than 1,600 employees, producing denim fabric on continuous warp yarn dyeing lines.
Indigo and sulphur dyeing of warp yarn is the most water-intensive stage of denim production. Under the conventional process, the site withdrew 76 million litres of fresh water a year from the supply of its organised industrial zone—OSB—and discharged 61 million litres of wastewater a year to the zone's shared treatment infrastructure. Every 10,000 metres of fabric consumed approximately 15,500 litres of fresh water in the wash steps alone.
Both flows carry a cost. Fresh water is purchased from the industrial zone and wastewater is charged on discharge to shared treatment infrastructure, so volume is a direct operating cost driver as well as a source of local water stress.
Location of the initiative: Denim production site in an organised industrial zone, Türkiye
Solution
Since 2022 the company has operated a modified warp yarn dyeing process that removes the fresh water feed from the pre-wash and post-wash steps. The process is patented in Türkiye as TR 2018 06545 B and was registered by the Turkish Patent and Trademark Office in May 2024.
The technical basis is a fixation approach that secures dyestuff which has not fully penetrated the fibre. Because the dye is fixed rather than rinsed, the wash water conventionally used to carry loose dyestuff away is no longer required. Caustic soda, used in conventional rope dyeing recipes, is also not required.
The method was developed in-house and runs on the existing dyeing lines. No additional infrastructure, machinery or capital investment was needed, which allowed the change to move from development into standard operation rather than remaining a trial.
By 2022 the process was applied on 100% of the company's active production lines, and reported impact data covers the 2022–2026 period on a continuous basis.
Figure 1: Water-Saving Warp Yarn Dyeing Process
Water-saving warp yarn dyeing process: line layout, water-feed control evidence and dye penetration, from the Çukurova University technical assessment (2017).
Figure 2: Annual freshwater withdrawal and wastewater discharge, 2020 baseline against the period after the 2022 process change.
Impact
Sustainability impact
Climate
The primary sustainability contribution of the initiative is water efficiency and wastewater reduction. The modified dyeing process reduces freshwater withdrawal by 92% and wastewater discharge by 99% against the 2020 base year, sustained across the 2022–2026 reporting period.
The initiative removes the need for fresh water in the pre-wash and post-wash steps and eliminates caustic soda from the recipe. As a result, it reduces both the volume of water withdrawn from the organised industrial zone and the volume of wastewater sent to the shared treatment infrastructure.
The reduction in water withdrawal and wastewater discharge lowers pressure on local water resources and shared treatment infrastructure. Removing caustic soda from the recipe also reduces the chemical load associated with the remaining wastewater. Upstream climate impacts associated with purchased chemical inputs are accounted for under GHG Protocol Scope 3, Category 1 (Purchased Goods and Services). The company reports against its sustainability targets and discloses relevant environmental performance through CDP in the Climate Change and Water Security areas (1).
Nature
Annual fresh water withdrawal from the industrial zone supply fell from 76 million litres to 6 million litres, a reduction of 92% against a 2020 base year. Annual wastewater discharged to the zone's treatment infrastructure fell from 61 million litres to 1 million litres, a reduction of 99%. In annual terms the change protects 70 million litres of fresh water and keeps 60 million litres of wastewater load out of the shared treatment infrastructure, reducing industrial pressure on the local ecosystem.
At production level, this corresponds to 15,500 litres of fresh water saved per 10,000 metres of fabric, or 1.55 litres per metre. Removing caustic soda from the recipe also reduced the chemical pollution load of the limited volume of water still discharged, as confirmed in recipe analyses reviewed by Çukurova University.
Social
Lower industrial abstraction and discharge reduce pressure on the water resources shared by the organised industrial zone and the surrounding area, easing competition for local water supply. The company reports this community-level effect qualitatively.
Business impact
Benefits
The change removes two variable operating costs: fresh water purchased from the organised industrial zone, and the discharge charge for wastewater sent to shared treatment infrastructure. Both scale directly with the volumes eliminated.
Product quality was maintained. Fibre cross-section penetration and wash, water, perspiration and rubbing fastness tests returned results identical to the conventional method, so no customer requalification of the fabric was required.
An independent technical assessment by a panel from Çukurova University's Textile Engineering Department validated the process and its quantitative results, and the process is registered with the Turkish patent office. Demand from global apparel brands for fabric with a lower water footprint under European Green Deal compliance programmes supports the commercial position of the product.
The company has also developed a dedicated label and logo for its Save Blue concept. The concept has been positively received by global apparel brands, including Nudie Jeans and Zara, and has strengthened the company’s commercial positioning in the denim market. In addition to its environmental benefits, Save Blue has also contributed to increased sales by offering customers a differentiated, lower-water-footprint product proposition.
Costs
The distinguishing cost characteristic is the absence of capital expenditure. No additional infrastructure, machinery or plant was installed, and the method runs on the existing continuous rope dyeing lines, so the financing barrier that commonly delays water efficiency projects did not apply.
The costs incurred sit in research and development rather than in assets: recipe development, fixation trials, quality and fastness testing, process standardisation across lines, the independent academic assessment, and patent registration. Ongoing cost is limited to monitoring through flow meters, line automation and the manufacturing execution system (MES). Operating cost moves in the opposite direction to the investment: purchased water and discharge charges fall in step with the volumes eliminated.
The project was carried out using internal company resources, without project-specific external financing or grants. However, the company benefits from general legal R&D incentives associated with its R&D Centre status. The main dependency is therefore technical rather than financial: sites require the capability to optimise the recipe and to standardise the process; without it, results vary between lines. Costs are contained by proving the recipe and the fastness results on a single line before standardising, so that no production capacity is committed until the quality evidence exists.
Impact beyond sustainability and business
Co-benefits
Removing caustic soda from the recipe reduces the chemical load on the shared treatment plant alongside the reduction in discharged volume. Freeing capacity at the industrial zone's treatment infrastructure benefits the other manufacturers connected to it.
Potential side-effects
The principal risk in wider adoption is limited technical capability at the recipe optimisation and process standardisation stage, where a poorly tuned recipe would appear as quality variation. The company manages this through the technical documentation behind the registered process, university–industry collaboration and applied technical training.
Implementation
Typical business profile
The model is most relevant to textile manufacturers operating continuous rope dyeing lines for warp yarn, particularly denim mills, and can be applied at different scales, especially in water-stressed regions or on shared industrial zone water and treatment infrastructure. The functions involved are production, dyeing technology, research and development, and environmental management. Because no capital investment is required, the model is accessible to companies at an early stage of resource efficiency maturity.
Approach
Baseline the water flows: Map fresh water withdrawal and wastewater discharge step by step across the dyeing line using flow meters and line automation data, and fix a base year for comparison.
Identify redundant wash steps: Determine where the fresh water feed exists to remove loose dyestuff rather than to perform a chemical function.
Develop a fixation approach: Hold dyestuff that has not fully penetrated the fibre so that the pre-wash and post-wash fresh water feed can be switched off.
Test product quality: Compare the resulting fabric with the conventional process for fibre cross-section penetration and for wash, water, perspiration and rubbing fastness before changing any production line.
Commission independent validation: Arrange an academic review of the process and its measured results to verify the quality and consumption claims.
Register the process: Document and protect the technical method through the Turkish patent office.
Standardise and roll out: Apply the recipe across all active production lines rather than leaving it on a single trial line.
Embed monitoring: Include water and wastewater indicators in daily operational routines, environmental performance reporting and sustainability targets, tracked through the manufacturing execution system (MES).
Stakeholders involved
Project leads: Project leadership sits with the company's R&D Centre, which developed and tested the recipe. The Sustainability team is part of the R&D organisation and supports environmental performance monitoring, KPI tracking and sustainability reporting for the project. Technical management, machinery and energy, and production functions support implementation and day-to-day operation.
Company functions: The R&D Centre developed and tested the recipe; the Sustainability team supports environmental performance monitoring, KPI tracking and sustainability reporting; technical management standardised the process across the dyeing lines; the machinery and energy department maintained the flow meters and line automation that measure the result; and production teams applied the process in daily operation. These functions work together to maintain a consistent set of performance figures.
Main providers: No external technology or equipment supplier was involved. The process was developed in-house and runs on the existing dyeing lines, so no vendor relationship was required to implement or to maintain it.
Other: The Turkish Patent and Trademark Office examined and registered the process in May 2024. Çukurova University's Textile Engineering Department designed the quality and fastness assessment, reviewed the recipe analyses and issued the independent expert report that evidenced the results to production teams and customers. A non-governmental organisation, the Business Council for Sustainable Development Türkiye—SKD Türkiye—supported dissemination within the sustainability ecosystem. Global apparel brands and corporate customers set the water footprint requirements that feed back into production specifications.
Key parameters to consider
The process is in standard operation: applied on production lines since 2022 and across 100% of the company's active lines, with continuous impact data for 2022–2026. It is patented as TR 2018 06545 B, registered in May 2024.
Technical prerequisites include:
continuous rope dyeing lines;
the capability to optimise dye recipes and to standardise the process; and
metering through flow meters and line automation.
There is no equipment prerequisite, no subsidy dependency and no minimum plant scale. Depending on the site’s existing infrastructure and technical capability, adoption may be achievable within a one-to-two-year horizon. Impact is measured against a 2020 base year using tonnage-based volume calculation, monitored in real time and reviewed by a periodic technical committee.
Implementation and operations tips
The main challenge was demonstrating that removing the fresh water feed would not degrade colour fastness or fibre penetration. This was addressed by designing the quality assessment academically and recording it in a formal expert report, so that production teams and customers had documented evidence before the lines were changed.
The second challenge is transferable rather than internal: other sites require sufficient process engineering capability to tune the recipe. Applied technical training and university–industry collaboration are the practical responses.
Adoption is supported by the absence of capital expenditure. The assumption that resource efficiency in textiles must be funded through new machinery does not apply in this case, which removes a common reason for deferring such projects.