Development of intelligent waste sorting system of low-value recyclable waste in Xiamen

The classification and recycling of waste are significant for environmental protection and resource conservation. In China, the fine sorting of low-value recyclable waste (LVRW) primarily uses manual sorting, which is inefficient and harmful to health. Automated sorting uses sensors to identify the type of waste on a conveyor belt, which is then automatically separated by a sorting organisation to improve the recycling process. A low-cost, high-performance sorting system was built in this paper. The system used a low-resolution industrial camera to capture colour images of waste and a pneumatic separator to sort the waste. The recognition accuracy of waste was improved by optimising the recognition model and using the copy-paste data augmentation method. Mark pneumatic valve control algorithm is proposed that achieves more than 99% waste recovery even under dense working conditions. The sorting system is suitable for sorting plants and has been applied to a case study of LVRW in Xiamen city. In the sorting experiments under complex working conditions, the purity and recycling rate of plastic and Tetra Pak wastes achieved over 95%. The experiment demonstrates the great potential of the system for waste recycling and will help solve the problem of municipal waste in developing countries.