Kong Chuilan, Wang Qianqian.
Summary:With the development of the plastic industry, plastic products appear in every corner of human life, and the resulting pollution is becoming more and more serious. In recent years, the concept of microplastics has been mentioned more and more. Among them, microfiber pollution, which dominates freshwater microplastic pollution in China, should also receive more attention. This paper introduces the main microfibers in the environment, namely textile industry wastewater, clothing washing, etc., and proposes three treatment measures, including waste textiles, reducing microfiber discharge in laundry wastewater, and improving the removal rate of wastewater treatment facilities. This paper argues that relevant enterprises should actively take a series of actions to reduce the production and emission of microfibers. At the same time, relevant departments such as ** should strengthen the policy guidance and supervision of relevant enterprises. In addition, microfibre-related science popularization activities should be strengthened to let the public understand how to reduce microfibre emissions in their daily lives.
Keywords:Plastics, microplastics, microfibers, environmental, pollutants.
Kong Chuilan, Wang Qianqian. Microfiber pollution and its treatment countermeasures. Biodiversity conservation and green development. 100 schools. December 14, 2023. issn2749-9065
1. Microplastics and microfibers
Microplastics are defined as plastic fragments with a diameter of between 1 micron and 5 millimeters. Analytical studies around the world have shown that microplastics have been found in a variety of places, including the human body, biota, air, water, sediment, and food. When microplastics are ingested by small organisms in the environment, their concentrations can increase with trophic levels through bioaccumulation and enter human food. It is estimated that the annual intake of microplastics per person is about 39,000-52,000 microplastic particles based on food consumption [1]. In addition, inhalation of microplastics released into the air, as well as contact with them, may also cause microplastics to enter the body. After entering the human body, microplastics accumulate in the respiratory system and liver, causing serious health effects [2].
Microplastics can be divided into four categories according to their shape: particles, fragments, films, and fibers [3]. Microfibers are fibrous microplastics, which have been defined by scholars as "fibrous structural materials with a diameter of less than 50 microns, a length from 1 micron to 5 mm, and an aspect ratio greater than 100",[4] which are widely found in water environments such as oceans, lakes, and laundry wastewater because of their small particle size, stable structure, and non-degradability. Many studies on microplastic pollution in freshwater in China have documented the dominance of microfibers in samples [5]. Understanding microfiber will provide an effective reference for relevant departments, enterprises and institutions to find an effective way to solve microfiber pollution.
Second, the main **
(a).Sewage from the textile industry
The textile industry is an important producer of synthetic fabrics. Plastic fibers, including polyester (polyester), polyamide (nylon), polyurethane (spandex), polyvinyl acetal (vinyl), polyacrylonitrile (acrylic) and polyvinyl chloride (chlorine), are important raw materials for clothing and other synthetic fabrics. Many steps in the production process, especially in the wastewater from printing and dyeing, contain a large number of microfibers [6]. Although factories are required to treat industrial wastewater, plastic fibers such as polyethylene, polyacrylonitrile and polyvinyl chloride are too small to be too small, cost constraints and limited treatment options make the wastewater treatment system unable to filter out all the microfibers in the wastewater produced by the textile factory.
(b).Laundry
Laundry wastewater is an important part of environmental microfibers**. The chemical and physical washing cycles in the laundry process can lead to abrasion on the surface of the laundry [7], which allows the microfibers to shed into domestic sewage and be treated in sewage treatment plants. As mentioned above, sewage treatment systems often do not remove all the microfibers, and some of them still enter the environment through filtration facilities. Outdoor washing, discharging domestic sewage directly into rivers, and dumping discarded clothing directly into rivers can release microfibers directly into the water environment [8].
(c).Other**
In addition to the main ** mentioned above, microfibers may also come from other activities and products such as car tire wear, building materials, plastic packaging, etc. Curtains, furniture, carpets, old interior paints and mattresses may also release some of the microfibres into the air. In addition, microfibers may also be released during the production and use of some plastic products, especially single-use plastic products (such as plastic bags, plastic bottles, etc.).
(c).Governance countermeasures
(a).Synthetic fabrics** utilization
Considering the importance of synthetic fabrics as microfibers, the use of waste textiles may be an effective way to solve the emission of microfibers in China. According to statistics, in 2019, the average annual output of waste textiles in China exceeded 20 million tons, but the recycling rate was only 15% [9]. China's waste textiles still have great potential to be tapped.
In 2022, the National Development and Reform Commission, the Ministry of Commerce, and the Ministry of Industry and Information Technology jointly issued the "Implementation Opinions on Accelerating the Recycling of Waste Textiles", which put forward the following goals: by 2025, the recycling system of waste textiles will be initially established, the recycling capacity will be greatly improved, the recycling rate of waste textiles will reach 25%, and the output of recycled fibers of waste textiles will reach 2 million tons. By 2030, a relatively complete recycling system for waste textiles will be built, the awareness of recycling among producers and consumers will be significantly improved, the high-value utilization channels will continue to expand, the level of industrial development will be significantly improved, the recycling rate of waste textiles will reach 30%, and the output of recycled fibers of waste textiles will reach 3 million tons [10].
At present, there is still a gap between the utilization rate of waste textiles in China and the target. In this case, we should start at least from both the public and the business end. On the public side, the popularization of science on waste classification should be carried out to raise the public's awareness of the reuse of waste textiles and encourage the participation of the whole peopleEncourage consumers to buy renewable textiles;Establish a network, such as a box, a site, a donation center, etc., and the public cannot be "left without a door". On the enterprise side, corresponding policies should be formulated to encourage textile enterprises to make the best use of waste textiles;Build a channel for resource sharing between enterprises, and provide a way for the recycling of waste textiles in the industrial chain. In France, for example, the recycling rate of waste textiles in France is 35%, mainly in the building materials and energy industries [11]. Building a platform for industries that produce waste textiles and industries that can use waste textiles may be a key step for China to improve the recycling rate of waste textiles in the next five to ten years.
(b).Reduction of microfibers in laundry wastewater
Some studies have shown that using laundry detergent instead of detergent, using fabric softener during laundry, and washing with water below 40 can effectively reduce the excretion of microfibers. In addition, some products, including laundry bags, can collect microfibers produced during laundry [6].
On the whole, cleaning products manufacturers should first be encouraged to start from the product itself and produce environmentally friendly products. Secondly, science education activities can be carried out for the public, such as how to reduce microfiber emissions in daily life. At the same time, consumers can actively choose environmentally friendly products in the market.
(c).Adopt more efficient wastewater treatment facilities
Because plastic fibers such as polyethylene, polyacrylonitrile, and polyvinyl chloride are smaller in size than other forms of microplastics, the microfiber removal rate in wastewater treatment plants is lower than the overall microplastic removal rate. A survey has counted the microfiber removal efficiency of some sewage treatment plants in China, and the removal rate of microfibers in about 40% of sewage treatment plants exceeds 90%, but about 50% of sewage treatment plants have a microfiber removal rate of 80% [12].
Considering the large amount of domestic sewage generated by China's huge population base and the large number of industrial wastewater generated by domestic textile factories, it may be very effective to reduce microfiber emissions by increasing the removal rate of microplastics. Relevant departments should formulate corresponding standards, which can make it mandatory to stipulate that the removal rate of microfibers and microplastics in the sewage of relevant enterprises shall not be less than a certain percentage, and strengthen supervision, and impose certain penalties on enterprises that fail to implement the requirements. At the same time, it will obviously increase the operating costs of sewage treatment plants and the burden on textile enterprises. The state and relevant authorities can provide certain policy support to encourage sewage treatment plants and textile enterprises to introduce more effective microfiber and microplastic removal devices, such as conventional activated sludge processes, oxidation ditches, and membrane bioreactor systems, which generally show high microfiber removal efficiency (99%) [12].
IV. Conclusion
This article introduces the ** of microfibers, mainly for the textile industry sewage and laundry washing. At present, the challenges are the low rate of waste textiles and the limited technology of sewage treatment facilities. Therefore, treatment measures include the utilization of waste textiles, the reduction of microfiber emissions in laundry wastewater, and the improvement of the efficiency of wastewater treatment facilities.
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Text: Kong Chuilan, Wang Qianqian.
Judge: Sherry
【Journal Introduction】