The development of a novel biorefining strategy for the valorisation of textile waste

纺织业产值超过3万亿美元，占全球GPD的2%。然而，快速时尚的模式导致了“一次性”服装和其他纺织产品的生产。因此，纺织品的寿命相对较短，通常在使用几次后就会被丢弃。仅在英国，每年产生的纺织废物就超过100万吨，即使与塑料废物的数量(每年250万吨)相比，这也是相当可观的。大多数纺织废物最终被填埋或焚烧，大约五分之一的纺织废物被回收和再利用，只有1%用于生产新服装的材料。为了解决纺织废物问题，废物和资源行动计划(WRAP)最近发起了纺织品2030倡议，呼吁政府、纺织业和研究机构共同努力，将目前单一的纺织业转变为英国的循环经济。《纺织品2030》的主要目标之一是“减少50%的碳排放，这足以使英国纺织业走上一条与将全球变暖控制在1.5摄氏度以内一致的道路”。为了增加纺织废料的回收利用，人们研究了各种机械和化学方法。然而，尽管机械回收技术可以回收由单一聚合物组成的纺织废物，但对于处理复杂废物，如聚棉服装(聚酯(PET)和棉花的混合物)，这是城市固体废物的关键成分，效率不高。化学回收方法旨在将纺织纤维分解成它们的积木，然后通过适当的纺丝技术合成新的聚合物，然后合成新的纤维。但化学循环是能源密集型的，天然纤维，如棉花(由纤维素形成)和羊毛(蛋白质纤维)将被降解到不能再用于制造纤维的程度。最近，哈德斯菲尔德大学生物精炼和生物加工中心的研究人员开发了一种酶辅助回收工艺，旨在将纤维素分解为其组成糖葡萄糖，然后将葡萄糖发酵成乳酸，从而合成可生物降解的塑料聚乳酸(PLA)。使用这项技术的目的是有选择地将纤维素分解成更小的单元，以便能够将其从涤棉的聚酯中去除。然后，这种聚酯可以用来制造新的聚酯纤维，这种纤维可能会被用来制造新的纺织品。有人提出，通过定制用于分解纤维素的酶，可以将纤维素从复杂的纺织废料中分离出来，同时保持足够长的分子链长度，以重新转化为纺织纤维。回收的短链纤维素将在哈德斯菲尔德大学的技术纺织中心进行表征并形成纤维。从纺织废料中再生的纤维将被探索其新的应用，如在伤口敷料中。回收的聚酯也将被表征和探索用于制造新的布料。将评估这一过程的经济、社会和环境影响。除了对不可再生资源的依赖外，还将对碳足迹和水足迹进行评估，以评估潜在的环境效益。还将审查这一进程对所有相关利益攸关方(工业、零售商、城市和农村社区)的社会影响。

The textile industry is worth over 3,000 billion dollars, representing 2% of global GPD. However, the model of fast fashion leads to production of "single use" clothes and other textile products. Therefore, textile products have a relatively short lifetime and are often disposed after a few uses. In the UK alone, over 1 million tonnes of textile waste are generated annually, which is significant even when compared with the amount of plastic waste (2.5 million tonnes annually). The majority of textile waste ends in landfills or incineration, while approximately a fifth of textile waste was recycled and reused and only ~1% was used to generate material for producing new clothing. To tackle the textile waste issue, Waste and Resources Action Programme (WRAP) launched the Textiles 2030 initiative recently to call government, textile industry and research institutes to work together and transform the current singular textile industry towards a circular economy in the UK. One of the key targets of Textiles 2030 is to "cut carbon by 50%, sufficient to put the UK textiles sector on a path consistent with limiting global warming to 1.5C". To increase textile waste recycling, various approaches both mechanical and chemical have been investigated. However, although mechanical recycling technology can recycle textile waste composed of a single polymer, it is not efficient to treat complex waste such as polycotton garments (a mixture of polyester (PET) and cotton), a key component of municipal solid waste. Chemical recycling methods aim to break down the textile fibres into their building blocks and then synthesis new polymers and subsequently new fibres via appropriate spinning techniques. But chemical recycling is energy intensive and natural fibres, such as cotton (formed of cellulose) and wool (protein fibre) will be degraded to a point that they cannot be used to generate a fibre again. Recently, researchers at the Biorefining and Bioprocessing Centre at the University of Huddersfield developed an enzymatic assisted recycling process aiming to breakdown cellulose into its constituent sugar glucose and then ferment the glucose into lactic acid, from which a biodegradable plastic polylactic acid (PLA) could be synthesised. Using this technology, the aim is to selectively breakdown cellulose into smaller units to enable its removal from the PET in polycotton. The PET can then be used to make new PET fibre which potentially can be used to make new textiles. It is proposed that by tailoring the enzymes used to breakdown the cellulose the cellulose can be separated from the complex textile waste while maintaining the length of the molecular chains long enough to be re-converted into textile fibre. The recycled short chain cellulose will be characterised and formed into fibre at Technical Textile Centre at the University of Huddersfield. The regenerated fibre from textile waste will be explored for its novel application, such as in wound dressing. The recovered PET will also be characterised and explored for making new cloth. The economic, social, environmental impacts of this process will be assessed. Both the carbon and water footprint in addition to the dependence on non-renewable resources will be evaluated in order to assess the potential environmental benefits. The social impact of the process to all involved stakeholders (industries, retailers, urban and rural communities) will be also examined