生命周期视角下废弃餐饮油脂炼制生物柴油的环境效益分析

废弃餐饮油脂的资源化利用是关乎公众健康和环境保护的重要举措.目前我国废弃餐饮油脂炼制生物柴油的环境效益尚不明晰、国家政策模糊,相关产业发展滞缓.本研究以国内废弃餐饮油脂炼制生物柴油的典型企业为例,利用GaBi软件对废弃餐饮油脂的收集、预处理、酯化和运输等过程全生命周期阶段的资源环境影响进行系统核算,评估其环境效益,以期为国家生物柴油行业发展和相关政策制定提供科学依据.研究结果表明:①整个生命周期过程中,酯化阶段的环境影响最大,各指标占比为52.91%～96.05%,其环境影响主要是由燃煤、用电和甲醇消耗引起;②敏感性分析结果显示,燃煤、用电、甲醇消耗和收集距离的变化对整个生命周期环境影响结果有着较大影响;③废弃餐饮油脂炼制的生物柴油生命周期化石能源消耗16406 MJ·t~(-1)、温室气体排放815 kg CO_2 eq·t~(-1),与石化柴油相比,具有较好的节能和温室气体减排效益.

Environmental benefits of biodiesel production from waste cooking oil based on the life cycle perspective

The appropriate utilization of waste cooking oil (WCO) can benefit public health and environmental protection. Environmental benefits of biodiesel production from WCO have not been fully investigated, which cannot fully support WCO-related policy decisions and the development of related industries. Taking a typical enterprise producing biodiesel from WCO as an example, this study investigated its environmental impacts throughout the whole life cycle based on the GaBi platform, including the processes of WCO collection, pre-treatment, esterification, and transportation. Results show that the esterification stage has the largest environmental impacts by contributing 53%~96% of the total. Its environmental impacts are mainly attributable to the uses of coal, electricity, and methanol. The sensitivity analysis identifies critical factors influencing the life cycle environmental impacts:the uses of coal, electricity, and methanol and the collection distance of WCO. The life cycle energy consumption and greenhouse gas emissions of biodiesel production from WCO are 16406 MJ·t^-1 and 815 kg CO₂ eq·t^-1, which are lower than that of fossil-based diesel. Findings of this study can provide scientific foundations for WCO management in China.