Comparative Study on Carbon Emission of the Cyanobacteria Mud Disposal Process

Abstract

Endogenous pollutants such as cyanobacteria have an essential impact on the global carbon cycle and climate. Finding a reasonable way to dispose of them has become an urgent task for current watershed management and ecological restoration. According to the engineering practice of cyanobacteria treatment by aerobic fermentation, the carbon emissions of three typical cyanobacterial resource utilization processes, aerobic fermentation without auxiliary materials, aerobic fermentation with auxiliary materials, and incineration for power generation, are compared in this paper, using the mandatory guidelines by the Intergovernmental Panel on Climate Change (IPCC). The results show that the treatment of cyanobacterial mud through aerobic fermentation without auxiliary materials can realize the goal of the harmless recycling of cyanobacterial resources with less carbon emissions, at 175.3 kg CO2·t−1. In addition, each link’s impact on the overall carbon emission process was analyzed. In aerobic fermentation with auxiliary materials, the carbon emissions were significantly contributed by the auxiliary materials, which was accounted for 46.3% of the carbon emission of the whole process and 32.77% of the drying-incineration process. In contrast, with the lowest carbon emission level, aerobic fermentation without auxiliary materials can avoid the production of carbon emissions caused by auxiliary fermentation materials.