Abstract
Today, due to the expansion of fashion and diversity in clothing, textile waste constitutes a large portion of recyclable materials. Through proper collection and recycling, these wastes can play an effective role in cost reduction and environmental protection.
Textile industry waste includes waste generated during the production process as well as dry municipal solid waste. At present, despite the significant volume of textiles that are discarded into the environment through waste streams, no comprehensive plan or dedicated industrial unit for the collection and recycling of these wastes has been established so far. Meanwhile, the process of fiber recycling is also important from an environmental perspective and in reducing environmental pollution. On the other hand, the multiple applications of recovered fibers in various industries lead fiber recycling units to produce raw materials with high added value and contribute to job creation.
The present study, conducted using an applied and documentary approach, examines the importance and necessity of recycling textile waste, different recycling methods in the textile industry, and the applications of recycled fibers in various industries. The results show that recycling textile waste, in addition to protecting the urban environment, reducing waste volume, and decreasing the space required for waste disposal, leads to savings in the consumption of non-renewable resources such as oil and petrochemicals, increases employment, and reduces the need for importing polyester fibers.
Keywords: Recycling, textile industry, urban environment, polyester, environmental engineering
1. Introduction
Rapid population growth, industrial development, and consumerism are among the most important factors contributing to the continuous increase of urban, industrial, and agricultural waste in human societies. Improper disposal of industrial waste in recent years has created numerous risks for human communities. Inappropriate management of industrial waste has led to serious crises in recent years (Moghtader Kargarān, Javad; Mirdavoud Banifatemeh; Mirabdoli Ghaibi, 1393).
Today, the issue of municipal solid waste is one of the major challenges faced by cities worldwide. Until a few decades ago, waste was considered unusable material and was simply discarded; however, with gradual technological advancements, it became clear that waste materials could be reused and reintroduced into the industrial cycle. When recycling operations are conducted scientifically, they yield economic benefits.
Given the rapid population growth and increasing attention to environmental protection, the collection, recycling, and reuse of waste materials within the production cycle have gained special importance. Wastewater and solid waste have emerged as major sources of environmental pollution, and extensive efforts are currently underway worldwide to address this issue (Hatami Zenuzi, 1400).
Due to the depletion of energy reserves such as oil, gas, and coal and the limitations of these resources, humans are seeking solutions to optimize the use of non-renewable resources, while also preserving the environment, which is one of the most critical concerns of modern society. One such solution is waste recycling, which reduces energy consumption and lowers the cost of manufactured goods.
The most common methods for disposing of textile waste and used textiles include landfilling, burial, and incineration. However, these wastes are in fact potential sources of energy and materials, and with proper management, they can be returned to the production cycle. Currently, three approaches are emphasized in waste management: waste reduction, reuse, and recycling (Salehi et al., 1397).
Environmental preservation and resource utilization have become major challenges in sustaining human life. In the textile sector, replacing materials with recyclable and durable alternatives and adopting environmentally compliant production methods have been proposed as substitutes for conventional production approaches (Khashaei, 1399).
Textiles are considered the second most polluting industry in the world. The average lifespan of a textile product is approximately three years; therefore, textiles generate a large amount of waste. About five percent of global landfill sites are occupied by textile waste. Waste generation during textile production or consumption is unavoidable. Therefore, providing appropriate analysis of consumer purchasing behavior and the product life cycle is essential. The amount of textile waste sent to landfills or incineration can be significantly reduced by understanding product dimensions and environmental compatibility. Textile waste occurs at every stage of the textile production process, including spinning, dyeing, finishing, garment sewing, and even during consumption.
The aim of this study is to examine and compare current textile waste recycling methods, measures taken in Iran, determine applications of recycled textile materials, and assess their role in preserving the urban environment.
2. Research Background
In 1399, Pasandideh Tashakori et al. examined waste management strategies aligned with extended producer responsibility (EPR) in Iran. The results showed that by utilizing successful experiences from other countries and applying EPR requirements, producers can accept legal and economic responsibility during product design to minimize environmental impacts throughout product lifecycles.
In 2015, G. Baydar et al. studied the life cycle of textile products produced in Turkey. The results showed that a multidirectional intervention approach across different life-cycle stages improves overall product sustainability.
In 1400, Leila Hatami Zenuzi examined waste management and appropriate recovery cycle strategies for environmental protection. The study demonstrated that scientific recycling processes yield economic benefits.
In 2014, Bahareh Zamani et al. at Yale University investigated the potential environmental benefits of various textile recycling techniques and strategies for sustainable textile waste management. The results showed that incineration has the highest global warming potential and primary energy consumption, while recycling demonstrated the best system performance, saving 8 tons of CO₂-equivalent and 164 gigajoules of primary energy per ton of textile waste.
In 2006, Morley et al. evaluated recycling, recovery, and reuse options for second-hand clothing and found that reuse offers significant CO₂ emission savings compared to recycling or disposal. The study reported that reuse of 33 kg of clothing resulted in CO₂ savings significantly greater than fiber recycling.
In 1400, Fatemeh Tahaniyan Fini et al. examined the performance of porous nanocomposites made from recycled polyester fibers based on natural polymers. The results indicated that these materials could be used effectively as oil-absorbing agents for aquatic environmental cleanup.
In 1399, Razvan Khashaei studied the importance of recycling polyester waste for producing textile fibers. The research showed that more than half of the polyester required by the textile industry is imported, highlighting the necessity of recycling polyester waste to support sustainable development and reduce imports.
In 1395, Majid Vahdatipour et al. examined the environmental benefits of adding recycled polyester fibers to clay soils in Mashhad metro line construction, showing improvements in soil strength and resistance.
In 1388, Ebrahim Mirzaei et al. studied asphalt pavements reinforced with recycled polyester fibers, demonstrating improved durability and mechanical properties.
3. Research Method
This study is an applied and documentary research conducted through library-based data collection. Its objective is to examine the importance and necessity of recycling industrial waste, focusing on waste generated by textile industries. It is hoped that this research will inspire academics, students, and environmental activists to develop innovative ideas in textile recycling and environmental protection.
4. Textile Waste Recycling
Textile waste recycling is highly significant from both economic and environmental perspectives. It prevents pollution and energy-intensive processes associated with producing textiles from virgin materials. Recycling also reduces landfill space requirements. Textiles create numerous landfill issues, particularly because synthetic fibers are non-biodegradable.
Recycling is generally divided into the following categories:
4.1 Physical Recycling
In physical recycling, production waste and post-consumer products are converted into new products through upgrading or reprocessing of composite plastic waste. Due to its simplicity, low cost, and environmental compatibility, physical recycling is more widely accepted than chemical recycling.
4.2 Chemical Recycling
Chemical recycling converts high-molecular-weight polymers into low-molecular-weight substances. The resulting materials can be used as reactants for producing new polymers. Textile waste recycling can serve as a solution to many economic, environmental, and social challenges.
Although textile recycling has a historical background, recent growth in fashion culture and increased textile consumption have intensified attention toward recycling. The lowest environmental impact is achieved through closed-loop recycling, where materials are recycled back into their original products.
5. Types of Recycling Technologies
5.1 Thermal Recycling Technology
Thermal recycling involves recovering thermal or electrical energy through the incineration of fiber waste.
5.2 Material Recycling Technology
Material recycling recovers polymers through fiber processing. Currently, converting polyethylene terephthalate (PET) into fibers is considered one of the most economical and widely applied approaches.
5.3 Chemical Recycling Technology
Chemical recycling recovers monomers through polymer decomposition. Impurities are removed during this process, resulting in monomers equivalent in quality to virgin materials.
6. Conclusion
Recovering textiles and garments for recycling provides both economic and environmental benefits. Recycling reduces pollution, energy-intensive processing, landfill space requirements, and resource consumption while lowering energy usage compared to virgin material production (Jeyaraman Anandha Kumar, 2020).
Textile waste includes production waste and dry municipal waste. Despite large volumes of discarded textiles, Iran currently lacks a structured recycling system. Recycling offers significant environmental benefits and enables the production of high-value raw materials and job creation.
The waste recycling industry presents significant potential for Iran to reduce unemployment (Zarghi & Rahmani-Zadeh, 1397).
Investment in domestic polyester recycling supports self-sufficiency, reduces imports, completes the textile value chain, and leverages national comparative advantages (Khashaei, 1399).
Recycled fibers can be used in asphalt concrete, soil reinforcement, and oil-absorbing nanocomposites, contributing to infrastructure durability and environmental remediation (Mirzaei et al., 1388; Vahdatipour et al., 1395; Tahaniyan Fini et al., 1400).
