Abstract: The physical and chemical properties of domestic waste are important criteria for selecting waste terminal treatment methods and assessing pollution potential. Based on the sampling data of source and terminal garbage in a city in South China in the past five years, the changes in its components and characteristics were compared and analyzed. The results showed that the average annual growth rate of domestic waste removal from 2015 to 2019 was 6.96%, and after the implementation of waste classification, the average annual growth rate decreased to 0.18% from 2020 to 2024. From 2020 to 2024, among the physical components of source residual waste, food waste accounted for the highest proportion (41.55%-51.43%),showing a fluctuating downward trend. It was followed by rubber and plastic waste (21.85%-31.69%), showing an increasing trend. While paper waste (10.99%-20.93%) and textile waste (2.30%-7.78%) showed fluctuating changes. The proportion of food waste in terminal domestic waste (49.55%-59.40%) had slightly increased year by year, while rubber, paper, textile and glass had all fluctuated and decreased. The moisture content of the source residual waste (48.51%-56.05%) was lower than that of the terminal domestic waste (56.66%-60.73%), while the low calorific value on a wet basis (7 750-10 876 kJ/kg) was higher than that of the terminal domestic waste (6 126-6 701 kJ/kg). The dry-basis contents of Hg, Pb, Cd, total Cr and As in the terminal domestic waste were all higher than those at the source. Therefore, waste must be properly classified at the source. Only in this way, the migration of water can be effectively prevented during the processes of collection, transportation and disposal, and the migration and re-adsorption of heavy metals can be reduced, so as to better achieve resource utilization.

Key words: domestic waste, residual waste, source, terminal, component, physical and chemical properties