粤港澳大湾区典型固废综合处置园区能量代谢特征研究

Solid waste in urban China has shown varied, broadly originated as well as abundantly produced. However, despite the fact that disposal methods for different solid waste are different, they all face the similar problems such as high energy consumption (EC) and producing large amount of secondary pollution. From the perspective of material flow analysis, this study constructed a framework of the energy metabolism analysis and evaluation index system for urban multi-source solid waste disposal. Taking the only national resource recycling park located in Guangdong, Hong Kong and Macao Great Bay area of China as an example, this study sets up three model scenarios of separate disposal, collaborative disposal and energy coupling collaborative disposal of solid wastes to comprehensively analyze and evaluate their energy metabolism characteristics from three aspects including input, output and efficiency. The results showed that the EC of material collaborative disposal is 27.54% higher than that of single disposal, while the EC of material energy coupled collaborative disposal is 3.73% lower than that of single disposal because of the internal reuse of waste heat and energy. The energy loss rate has decreased from 73.17% in the single disposal mode to 65.82% and 63.41% respectively, through material and material-energy coupling synergy, in which the waste gas storage as the main energy loss accounting for nearly 50%. From the perspective of energy efficiency, the energy consumption intensity under the material energy coupling collaborative mode is 11.54% and 17.03%, which are lower than that under the single disposal mode and the material collaborative disposal mode respectively. However, energy recycle utilization rate of material energy coupling collaborative mode is only 12.22%. To sum up, strengthening the centralized and collaborative disposal of urban multi-source solid wastes can enhance the substitution of resources and energy as well as reduce the risk of regional ecological environment. However, for the future growth in China, the utilization of various low-temperature flue gas and remaining heat from the wastewater is still an important direction for balancing energy use and ensuring low-carbon emission under the collaborative disposal of solid wastes. This study provides a set of quantifying evaluation methods and indicator systems for the energy metabolism optimization process of urban multi-source solid waste disposal, which will help to promote the comprehensive utilization of urban solid waste in China and the realization of the green and low-carbon cycle target.