Environmental Standards for Reducing Pollution from Textile and Leather Industry

The textile industry is the oldest and diverse sector in the world. It includes the entire production process of transforming natural and man-made fibers into finished products like garments, industrial textiles, and other consumer products. Textile processes pollute the environment and pose serious environmental and health hazards. Therefore, environmental standards have been established for the textile and leather industry to control its pollution.

The main operations of the textile processing industry are de-sizing, bleaching, dyeing, neutralizing, scouring, mercerizing, printing, and finishing. These operations discharge high-level toxic effluents that cause soil contamination, pollute the air, groundwater, and surface water. Also, it can have adverse effects on the environment in general and human health. Moreover, the textile industry is also the main source of hazardous waste.

The environmental problems do not emerge only from the textile processes. For example, nonorganic cotton cultivation uses more pesticides compared to any other crop in the world. This causes serious environmental impacts. Natural fibers require more processing steps than artificial fibers. Besides, certain dyes are known to be carcinogenic.

The utmost point of environmental concern is a discharge of a large amount of wastewater loaded with chemicals. Other important issues are energy consumption, air pollution, solid wastes, and odors. The main pollutants present in textile waste effluent are toxic heavy metals, biochemical oxygen demand (BOD), chemical oxygen demand (COD), residual chlorine, dissolved solids, color, sludge, used oil, dyes, and non-biodegradable organics.

With such complex textile processes and the growing concern of their impact on the environment, it was essential to establish harmonized and globally recognized standards for the textile industries. Global Organic textile standards, (GOTS) was introduced which has universal recognition and has more than 3000 certified textile processing, manufacturing, and trading people in more than 60 countries. It has adopted standards for processing textile goods using fibers that are environmentally, socially, and economically sustainable.

Apart from GOTS, other international organizations have established various environmental standards and measures to reduce pollution from the textile industry. Some of them are EKO sustainable textile standard, Organic textile standard (Italy), Organic Fiber Standards (USA), Standards for Processing of Organic Textile Products (Argentina). The standards set by these organizations ensure the reduction of textile pollution and promote the use of organic fibers and eco-friendly textile production methods.

There are numerous environmental standards established to reduce the environmental impacts of the textile industry. Some general and important ones are- use of natural and azo-free dyes, use of organic fibers, minimizing carbon footprint, reduce water and energy usage, etc. The textile industry releases a large number of volatile chemicals and pollutants mainly from the coating, finishing, dyeing, and printing processes.

The standards to reduce textile pollution focus on avoiding the use or discharge of alkylphenol-ethoxylates and minimum use of organic solvents. Also, avoiding non-degradable surfactants and spinning oils in washing and scouring processes. Pad batch-dyeing is recommended as it is an effective method. It saves 80% of energy requirement and 90% of water consumption. It also reduces the usage of dye and salt.

Exhaust dyeing is advised for knitted items. Further, the use of jet dyers is favorable compared to winch dyers. One must avoid using benzidine-based azo dyes, chlorine-based dyes, and dyes having cadmium and other heavy metals. Also, these standards advocate avoiding toxic dye carriers containing chlorine and finishing agents. Peroxide-based bleach must be used instead of sulfur and chlorine-based bleach. The standards recommend that VOC (volatile organic compound) emissions must be less than 1kg carbon per metric ton of fabric.

The introduction of new technology has also played an important role in reducing textile pollution. The new reactive dye, Avitera-SE, is recommended for cotton dyeing. Along with the latest technology, it will significantly reduce the water consumption for cotton dyeing compared to the traditional methods. Further, an innovation called ‘Gentle Power Bleach’ reduces energy and water consumption by 30-40% while bleaching. Also, this technique cuts down carbon emissions.

The leather industry consists of refining raw skin into leather products. This whole process requires several complex chemical and mechanical processes. Among all these processes, tanning is the most important process. The leather industry generates a high level of pollution by using chemicals such as biocides, surfactants, and wastewater discharge.

Several measures to reduce the environmental impact of tanneries have been developed for the leather industry. Some of the important ones are: It is necessary to train the staff for occupational health and safety of workers. Tanneries must develop an environmental management system. The workers must be provided masks to avoid inhaling toxic gases. There must be a proper drainage system to prevent the formation of hydrogen sulfide in the tannery.

The solid waste from the tanneries must not be used for poultry food. Furthermore, there are techniques available to reuse the chrome, discharged in the effluent such as direct recycling of chrome, recycling of chrome after precipitation, etc. Wastewater from the tanneries should be treated at two levels. The first level treatment includes mechanical screening, pH leveling, flocculation, solidification, and sedimentation.

The second level of treatment requires a biological process to remove organic matter from the wastewater. Treatment technologies like activated sludge, percolating filter, aerated lagoon, facultative lagoon, etc. are available. Activated sludge treatment is a proven and effective technology to treat tannery wastewater and is used all over the world.

Research has shown that numerous chemicals released by the leather industry have harmful effects on the environment. Hence, it is necessary to make efforts to reuse and recycle chemical components. Therefore, further environmental recommendations have been suggested to make leather production environment friendly. Training programs of modern techniques must be provided to all the workers.

Safety materials like protective shields, acid-resistant gloves, aprons, masks must be made available to each worker. Informative tips for safety, health, and the environment must be displayed in the tanneries. To conserve water, orderly washing instead of continuous washing method should be used. This will not only save water but also reduce the amount of wastewater treatment. Eco-friendly chemicals like enzymatic products must be used to replace sulfides and surfactants.

With the help of new dyeing technologies, major textile processing countries like China, India, and Bangladesh will reduce their water consumption by over 50%. In the path of adopting environmental measures, major apparel and footwear brands and retailers have set a goal of achieving zero discharge of hazardous chemicals (ZDHC) by 2020. This plan has set new standards of environmental performance in the textile and leather industry.

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