Su Qiong, Dai Hancheng, Xie Shuyan, Yu Xiangying, Lin Yun, Singh Vijay P, Karthikeyan Raghupathy
Department of Agricultural Sciences, Clemson University, Clemson, South Carolina29634, United States.
College of Environmental Sciences and Engineering, Peking University, Beijing100871, China.
Environ Sci Technol. 2023 Feb 7;57(5):2093-2104. doi: 10.1021/acs.est.2c08583. Epub 2023 Jan 25.
Greenhouse gas (GHG) emissions from integrated urban drainage systems (IUDSs), including sewer, wastewater treatment plants (WWTPs), and receiving water systems, have not yet been integrated due to the lack of modeling tools. Here, we updated the computable general equilibrium-based System Dynamics and Water Environmental Model (CGE-SyDWEM), a recently developed model simulating the water-energy-carbon nexus at the watershed level, to calculate the direct and indirect (electricity use and external) GHG emissions from IUDSs considering carbon mitigation strategies and water engineering practices. The updated CGE-SyDWEM was applied to an estuary watershed in Shenzhen, the fourth largest city in China. With increasing socio-economic development and water infrastructure systems upgrading, GHG emissions are projected to increase from 129.2 (95% CI: 95.9-162.5) kt in 2007 to 190.7 (144.8-236.6) kt in 2025, with 89% from WWTPs (direct: 17%; electricity use: 65%; and external: 7%), 10% from the sewer (direct: 1% and electricity use: 9%) and 1% from receiving waters (direct). Carbon mitigation can reduce GHG emissions by 7% and emission intensity by 6% by 2025, with 63% contributed by external emission reduction from chemical uses. The integrated model can aid water, energy, and carbon decision-makers in finding cost-effective solutions for water and energy security in the future.
包括下水道、污水处理厂（WWTPs）和受纳水系统在内的城市综合排水系统（IUDSs）产生的温室气体（GHG）排放，由于缺乏建模工具，尚未得到整合。在此，我们更新了基于可计算一般均衡的系统动力学与水环境模型（CGE-SyDWEM），这是一个最近开发的用于模拟流域层面水-能源-碳关系的模型，以计算考虑碳减排策略和水利工程实践的IUDSs的直接和间接（电力使用和外部）温室气体排放。更新后的CGE-SyDWEM被应用于中国第四大城市深圳的一个河口流域。随着社会经济发展和水基础设施系统的升级，预计温室气体排放量将从2007年的129.2（95%置信区间：95.9 - 162.5）千吨增加到2025年的190.7（144.8 - 236.6）千吨，其中89%来自污水处理厂（直接排放：17%；电力使用：65%；外部排放：7%），10%来自下水道（直接排放：1%，电力使用：9%），1%来自受纳水体（直接排放）。到2025年，碳减排可使温室气体排放量减少7%，排放强度降低6%，其中63%来自化学用途的外部减排。该综合模型可帮助水、能源和碳决策者在未来找到具有成本效益的水和能源安全解决方案。
