Basics of Textiles | Industry View | Textile Articles

A discussion paper on circular practices in the chemicals and dyeing segment in the textile and apparel sector

Published: March 19, 2020
Author: TEXTILE VALUE CHAIN

HI. Current Status
The textile and apparel industry has been designated as the second most polluting industry after petrochemicals. The adverse impact on environment and drain on resources is significant be it water consumption (one cotton shirt could take up to 2700 litres of water1), energy consumption in production processes, excessive use of chemicals (a large part of which are also carcinogenic), discharge of toxic waste and large amounts of post consumption apparel waste being simply sent to the landfills despite the potential to recycle (globally less than 20% of clothing is recycled). In terms of greenhouse gas emissions (GHG) too, the sector is projected to account for 25% of the world’s carbon budget by the year 2050.2 Given that rising demands and fast fashion have impacted ecosystems through GHG as well as pollution, long-ranging interventions are needed. Recognizing the gravity of the situation and the need for action, the European and American brands are beginning to sign up to global commitments and action to contain the rising pollution and waste. Some of these initiatives are Cradle to Cradle certifications3 (following standards on raw material and chemical use, designing clothes meant for reuse and recycle etc.) and circularity commitments as part of the Global Fashion Agenda’s 2020 commitment4. However, focus in developed consumer markets’ has been limited to post-consumer collection and processing of apparel and other textiles waste. For India, even though recycling has to play a big role in diverting apparel and textile waste from landfills, water bodies and incinerators, more emphasis must be laid on the resource intensive manufacturing processes. India, along with China, Bangladesh, Vietnam, Cambodia, etc. is one of the biggest hubs of textile and apparel production in the world. In these countries, environmental pollution and poor working conditions in the industry has been a cause for concern since decades.

Dyeing – the main source of pollutants and exploitation of water
The use of chemicals in the textile and apparel industry occurs at various stages of the production process, starting from pesticides in fibre cultivation, to use in manufacturing processes and apparel care. The industry uses more than 2000 chemicals in its processes; which amounts to about 25% of all chemicals produced globally. Synthetic dyes contribute to most of the water pollution caused by this industry. Nearly 20% of global water pollution is linked to synthetic dyes. This is caused by the use of non-biodegradable petroleum-based colorants to dye textiles. Also, the use of toxic agents to fix colorants on the textiles lead to their release into the surrounding ecosystems5. Globally, around 2 lakh tonnes of chemical dyes are lost as industrial effluents, most of which ends up in the freshwater sources like rivers.
Additionally, dyeing and finishing processes use a lot of water—it is estimated that these processes use over 90% of the total process water requirement in the textile and apparel manufacturing industry (in terms of wastewater discharge). A few decades ago, when “direct dyeing” was the norm, water use was minimal as the process involved only one cycle of rinsing the fabric in a dye bath—this process had been replaced gradually as the dye tended to fade quickly. This led to the development of “reactive dyeing”. Advanced chemicals, colourants, and additives were brought into the mix; this enhanced the quality of dyed clothes immensely, but also led to consumption of huge quantities of water. Currently, conventional dyeing can require water as much as 40 times the weight of fabric.

Other factors contributing to pollution from dyes
Insufficient common infrastructure

While it is obvious that the primary area of intervention is the chemical agents and dyes used in the sector, there are other chronic structural issues plaguing the industry. Most textile clusters in India dedicated to dyeing and finishing processes (like washing of denim) are served by centralized Effluent Treatment Plants (ETPs). These ETPs serve as common infrastructure for most businesses—MSMEs form a large percentage of Indian industry; it would be difficult for individual businesses to treat their wastewater. In spite of the good intentions, these ETPs fail to provide sufficient treatment capacity for the clusters. Most of these facilities were planned decades ago, and are now handling wastewater 2-3 times their rated capacity.

The Panipat cluster was established after India’s Independence, when artisans fleeing from cultural centres like Lahore and Peshawar settled there. It was a major handloom hub, which slowly got transformed into a cluster known for home furnishing and a large recycling industry. Dyeing units came in various parts of the city. As most of these units lacked water treatment facilities, pollution of soil and groundwater in and around the city became a critical problem. The Sector 29 industrial area, lying on the outskirts of the city, was then designated as the official dyeing cluster of Panipat. All units were shifted there and a CETP was provided according to the estimated capacity at that time (late 1970s and early 80s). Today, Panipat has over 600 dyeing units, and the CETP is grossly insufficient to meet the needs of all of them. There is a need to re-evaluate the suitability of existing infrastructure and take immediate action to provide adequate capacities, failing which environment and water pollution would be impossible to contain.

Lack of segregation, compliance, and necessary capital

Many dyeing and washing units across the country do not comply with regulations demanding that their toxic wastewater must be treated before releasing in the common drain/sewer. This is caused partially due to weak enforcement of regulations, and partially due to lack of capital available for investment. In CRB’s interaction with dyeing units, it has clearly come to light that in the absence of strict enforcement of regulations on wastewater management, companies that do follow regulations and norms face a clear short-term cost disadvantage. In many locations, surprise audits and field visits have revealed that units sometimes release their toxic waste into nearby farmlands, in the municipal sewers, or even on roads that are unmonitored. This is especially harmful to municipal ETPs as they aren’t equipped to handle industrial toxins. Microbes that are crucial for municipal water treatment are killed off by the toxins, causing cascading problems in the regional water system. Also, in most dyeing clusters, water from different waste streams are mixed in a single effluent drain which carries it to the ETP. Such mixing of water streams leads to loss of valuable materials like colour pigments, and recoverable chemicals.

Lack of standards for chemical use and inadequate disclosure on chemicals usage

At the moment, not much disclosure is made on the use of chemicals in the textile and apparel sector and neither are there any universally accepted standards for preventing use of toxic chemicals. Some form of regulation and control is exerted through Restricted Substance Lists that are usually drawn up in response to government regulations. It should be noted that there are some international regulations that aim to control the use and management of toxic chemicals in manufacturing processes. Some of these are EU’s REACH (Registration, Evaluation, Authorization and Restriction of Chemicals, US’ Toxic substance control act and China’s REACH (MEP order 7)6. However, there is no particular focus on the textile and apparel sector. Further, current initiatives on chemical management are largely focused on denim production only.

II. Trends towards corrective action

The need for corrective action to contain and mitigate the adverse impacts on resource consumption and environment in the apparel and textile sector is well established. In India, as well there are several developments that are nudging the sector onto a more sustainable and efficient path. Firstly, the government’s focus on resource efficiency and the draft national resource efficiency policy7 provides an overall guidance on promoting responsible consumption and production. Several state industrial policies integrate the need for reducing resource consumption (material, energy, water), highlight the need for effective waste management especially for toxic & hazardous wastes (air, chemicals, water etc.), and are exploring supportive policies for start-ups that provide sustainable solutions. Large apparel brands (domestic and international) have made commitments towards reducing resource consumption, transitioning to sustainable materials and phasing out waste. New collaborations and partnerships are being forged to drive this agenda. For e.g. SU.RE8 – a collaboration of leading brands in India to move towards sustainable fashion. This has clear implications for their supply chains as suppliers will need to develop capacities and initiatives to align to these commitments. Against these developments, circular economy principles provide a robust framework to guide the textile and apparel sectors towards sustainability.

Circular apparel shows the way

Circular economy is a regenerative system where material and energy flow in closed-loop, and the concept of “waste” is designed out of the system. All materials in such a system are reused, recycled or repurposed. Products and services are designed in a way that allows for easy repurpose and recycling. Circular economy in the textile and apparel sector (circular apparel) can provide answers to some of the challenges. Centre for Responsible Business (CRB) has developed a circular apparel framework for identifying priorities for intervention in each segment of the textile and apparel value chain. The framework identifies the following components of circularity in this industry.

  • Design for closed loops – design of business model, products, production systems and supply chain in a way that encourages closed loop flow of materials and energy
  • Raw materials – production, procurement and processing of raw material
  • Chemicals – natural alternatives, processes that minimize chemical use, types of chemicals that minimize water use
  • Energy – renewable energy, captive power plants, equipment upgradation, energy efficiency
  • Water – recycling of process water, minimize groundwater use, ZLD
  • Waste – industrial symbiosis, recycle, reuse, repurpose, minimize process waste, prevention of pollution
  • Business ecosystem (internal and external) – overall support structure, common infrastructure, socio-political situation, availability of credit, working conditions and facilities for labourers, protocols for operating under emergency conditions.

For the dyeing segment, chemicals, water and waste are the most relevant components, although there are interlinkages and overlaps between components. Based on CRB’s interactions with several stakeholders (large brands, suppliers & manufacturers, chemical experts, start-ups and innovators, research institutes), the following have clearly emerged with regards to use and management of chemicals in the textile and apparel sector:

– Need for an industry standard with clear guidelines on use and disposal of chemicals (amongst other things). Alternatives are available; awareness is required.
– Clear regulations on phasing out and banning widely used harmful chemicals.
– Focus on technologies that reduce the need for chemicals or use of water in the manufacturing process. Further, more R&D is needed to identify and promote affordable technologies for wastewater management

Holistic changes in business model
Pursuing circular economy will lead to overall greening of business processes and value chains. Such changes save money, and make the business more resilient to external shocks.

Adoption of low-cost, stand-alone techniques
Bodhi, a small block-printing workshop based in Vadodara, Gujarat, runs on the principles of circular economy. Bodhi combines a number of low-cost technological solutions with good labour practices and a long-term sustainability approach. Their rooftop solar installation saves energy costs (and emissions) by preheating boiler water for steam generation. They have a bioremediation facility to recycle process water; this reduces their need for freshwater input. Bodhi has also installed rainwater harvesting system with underground storage, reducing municipal and groundwater use. Further, they employ artisans and craftsmen on permanent payroll with fixed salaries. This reduces income uncertainties for its employees during off-season. Workers are hired and trained on-site, where they learn and adapt. Home based embroiders, mostly women, are trained by Bodhi; they are supplied with equipment and raw material and finished goods are transported back by the company.

Innovation in chemicals and treatment processes

Innovation in the effluent treatment process

The National Green Tribunal mandated zero liquid discharge from industries in India. A Zero Liquid Discharge (ZLD) system involves a range of advanced wastewater treatment technologies to recycle, recover and re-use the ‘treated’ wastewater and thereby ensure there is no discharge of wastewater to the environment. To achieve ZLD, common effluent treatment plants (CETP) are established at large scale industries or prominent industrial clusters throughout India. In India, where the industry is highly fragmented, achieving economies of scale in the effluent treatment becomes a challenge. Most of the dyeing industries operate as small clusters and have a wide spread in a region. Collection and treatment of effluents becomes a huge challenge. There are certain technologies available which makes ZLD systems economically feasible and efficient. A typical ZLD is a multi-component system comprising of three main components:

  • Pre-treatment Unit (Physico-chemical chemical & Biological)
  • Reverse Osmosis (Membrane Processes)
  • Evaporator & Crystallizer (Thermal Process)

Adoption of Zero Liquid Discharge Policy in Tirupur Textile Cluster (Tamil Nadu)
Tirupur is an important textile cluster in India famous for knitwears and other functional domains to the textile industry. Approximately 3 lakh people are employed across 500 plus knitting units and 300 plus dyeing units9. It generates approximately 185 MLD of industrial waste water10. Tamil Nadu Water Investment, a Special Purpose Vehicle was formed with 54% of the shareholding between IL&FS and rest with the Government of Tamil Nadu with an aim of providing and supplying potable water to the town and ensuring zero discharge from the industries to pollute the river11.

The CETP system in Tirupur completely eliminates liquid discharge from the system. It ensures recovery of salt and water from the effluents. The recovered salt is then sent back to the industries. The RO plants in the ZLD system recover around 95% of the total permeate water and the MVRE / MEE systems recover and only 0.5% to 1% of the total volume is discharged by solar evaporation pan12. This system recirculates around 95% of the total water back into the system, thus making it an extremely efficient system.

Technological innovation in the dyeing process

Use of reclaimed Carbon dioxide in the dyeing process13

This process replaces water with carbon dioxide for the dyeing process. This carbon dioxide is reclaimed from the industrial processes. As, there is no water involved, so there is no waste water generation, thus making it a closed loop system and while eliminating the operating costs of industrial effluent treatment. DyeCoo based in the Netherlands, developed this process that does not need chemicals to dissolve the dyes. It uses 100% pure dyes and with an uptake of 98%, wastage is minimal, making it a very efficient system.

Since this is a dry process, it saves energy by eliminating the need to evaporate water from fabric. Additionally, efficient colour absorption and short batch cycles makes this technology energy efficient. Due to the process being waterless, this dyeing process is independent of geography in terms of water availability.

Hybrid pigments14

This technology developed by Ecofoot uses porous polymer particles. This is composed of a dye chemically linked to a polymer particle that reacts with cellulose fibres below 25°C. This process does not need salt in the dyeing process. So, this eliminates the need for boiling the water for the dyeing process. This also avoids using toxic reducing agents. This system saves more than 50% of water in the intermediate and final rinses, making it an eco-friendly process. Cotton pretreatment technique This is a fairly common technique used by many industries across the world. Here, cotton is first chemically treated before the dyeing process to get ionic cotton. Dow Inc15 created a chemical for pretreatment of cotton, known as ECOFAST Pure. This is applied prior to the dyeing process to produce cationic cotton. Cationic cotton has a higher affinity towards negatively charged molecules like dyes. This decreases the use of chemicals in the dyeing process by 90%, while the use of dye and water is reduced by 50%. Thus, it meets the ZDHC Roadmap to Zero Programme standards. In another method, developed by ColorZen’s16, the raw cotton fibre is pre-treated using a solution comprising a wetting agent, caustic soda and ammonium salt. The treated raw cotton exhibits increased ability to retain the dye without the need of additional fixation chemicals. This method reduces the usage of toxic chemicals by 90% and water by 95%.

Innovative dye and auxiliaries17

Huntsman Textile Effects introduced Avitera dyes, one of the most widely used dyes in chemical dye industries in the Indian subcontinent. These dyes are polyreactive, and readily bond to the raw cotton fiber and are free from p-chloroaniline (PCA). It provides a high reaction and fixation rate with cellulosic fiber, leaving very little unfixed dye to be removed by using tri-functional chemical reactivity. It reduces water consumption by 50% and salt consumption by 20%.

Towards sustainable dyeing at Multifabs Ltd. Bangladesh18

Multifabs Ltd. is an export-oriented knitwear manufacturer and major supplier to Lindex Group, based in Dhaka, Bangladesh. Like its peers in the country, Multifabs Ltd. also used monofunctional reactive dyes that yielded fixation rates as low as 50-60% and consumed substantial amounts of resources. Lindex to have sustainable sourcing of its products. As a result, Multifabs Ltd. switched to multifunctional dyestuffs. Multifunctional dyestuffs provide a high reaction and fixation rate with cellulosic fiber, leaving very little unfixed dye. This reduced the need of rinsing. They realized the benefits of sustainability and achieved lower operating costs. With this shift, they were able to reduce the water usage by 24 liters per kilogram of fabric as the rinsing requirement was reduced. The processing time also got reduced from 10.05 hours per tonnes to 9.15 hours per tonnes. They were able to save energy usage by 1.7 kWh/Kg fabric in the dyeing process as the requirement for groundwater extraction was reduced. There was reduction in the treatment costs of wastewater due to 15% – drop in the BOD and COD levels.

Herbal dye

These dyes are made from natural colour pigments sourced from the products of plants. The colour pigment formed is made a solution and the fabrics are dipped in the solution for dyeing. The colours are natural, lustrous and have good endurance. Most of the products used are organic. The common myth associated with these herbal products is that they don’t have any adverse impact on the environment. The reality is that they have low impact but not certainly ‘no impact’.

Power dyes from textile fibers19 These dyes are manufactured by converting the textile wastes into pigments. Natural chemicals, fabric fibers are crystallized through sophisticated techniques into an incredibly fine powder that can be used as a pigment dye for fabrics. This dye is applied as a suspension rather than as a solution in case of most of the other dyes, making it easier to filter the effluent. This technique was developed by an Italian company called Officina+39. The biggest benefit of this dye is the flexibility in its application technique. It can be applied to fabrics using various methods like exhaustion dyeing, dipping, spraying, screen printing, and coating.

III. Way Forward

The apparel and textile sector has already initiated a move towards more sustainable and circular practices. While it will require a shift in mindsets, capacity building, strengthening of the eco-system (availability of finance, new technologies, policy incentives, clear regulations etc.) to make this movement more widespread; it cannot be denied that these aspects of sustainability can no longer be ignored. In fact, the current pandemic which has resulted in massive disruption to production and consumption, will lead to change in consumer behaviour. It can be fully expected that focus will be on healthier and more sustainable options and the trend will be on greater transparency and traceability on products, their origins and the use of harmful substances if any. Brands will focus on sustainable supply chains and government regulations will tighten to support environment-friendly production practices. The good news is that there are alternatives available for more responsible production and now is the opportunity to build greater business resilience through these cleaner and greener practices. It is time to hit the reset button and adopt models and partnerships that help us future-proof ourselves and help move towards a more sustainable world for all.

CRB (www.c4rb.org) is a think-tank that undertakes policy and action oriented research on issues of sustainability. As one of its focus areas, CRB is undertaking work on inclusive policy making on Circular Apparel. For more details on our work on Circular Apparel, please contact: [email protected]

Related Posts