农村多能源系统（rural multi-energy system，RMES）能有效推动农村地区能源转型，具有提高经济和环境效益的潜力。然而现有的农村能源系统未充分考虑能源设备的耦合使用，也缺乏对市场政策影响的考量。提出了一种考虑热解和沼气池设备联合运行、阶梯碳交易（carbon emission trading，CET）与绿色证书交易（green certificate trading，GCT）耦合机制和全生命周期环境评估的低碳经济优化模型。首先，建立了基于热解设备和沼气池联合的RMES运行框架，明确了各能流和设备间的耦合关系。其次，引入了碳-绿证耦合的市场交易机制，借助市场调控作用提升可再生能源利用率。然后，基于环境因素建立了系统全生命周期评估（life cycle assessment，LCA）过程，量化了不同阶段的碳及标准污染物排放量并纳入模型优化体系。最后，通过多场景算例对比分析，结果表明该方法能够有效提高环境效益，促进可再生能源消纳并提高系统的经济性。

The rural multi-energy system (RMES) can effectively advance the energy transition in rural areas and holds the potential to enhance economic and environmental benefits. Nevertheless, the existing rural energy systems fail to fully account for the coupled utilization of energy equipment and lack consideration of the impacts of market policies. This paper proposes a low-carbon economic optimization model that takes into account the combined operation of pyrolysis equipment and biogas digesters, the coupling mechanism of carbon emission trading (CET) and green certificate trading (GCT), as well as life-cycle environmental assessment. Firstly, an operation framework of RMES based on the joint operation of pyrolysis devices and biogas digesters is constructed to clarify the coupling relationships among various energy flows and equipments. Secondly, a coupled market trading mechanism integrating carbon and green certificates is introduced to raise the utilization rate of renewable energy via market regulation. Thirdly, a life cycle assessment (LCA) procedure for the system is established with environmental factors taken into consideration, which quantifies carbon emissions and standard pollutant discharges at different stages and incorporates these indicators into the model optimization system. Finally, comparative analysis is conducted through numerical examples under multiple scenarios. The results demonstrate that the proposed method can effectively boost environmental benefits, facilitate the consumption of renewable energy and improve the economic performance of the system.