Challenges and Limitations in Recycling of Post-Consumer Cotton Denim Waste into New Textiles

This study investigates the feasibility of recycling post-consumer cotton denim waste into new yarns by examining the effects of recycled fibers percentage, twist level, and spinning methods (ring vs. rotor) on the yarn and fabric quality. Recycled cotton fibers, blended with chemically recycled polyester in 3 different ratios, and 12 samples were developed, which then knitted into single jersey fabrics. Fiber yield and waste generation during the yarn production were critically monitored to check the effectiveness of recycling process. Results indicate that increasing recycled content by more than 10% significantly degrades the yarn strength, elongation, and fabric durability due to the fiber shortening from prior use. Mechanical recycling yielded only 45–50% usable fiber, with higher waste percentages in yarn production leading to greater processing losses. The resulting developed knitted fabrics exhibited poor pilling resistance (Grade 1) compared to virgin cotton blends (Grade 4). Statistical analysis confirmed that the percentage of recycled fibers critically impacts yarn tenacity and breaking force. Post-consumer textile recycling holds promise for circular fashion, but current mechanical methods face limitations in producing high-quality yarns. This research raises important questions about the feasibility of large-scale post-consumer textile recycling in achieving sustainability goals while maintaining quality of final product.