PSXII-8 Environmental cost effects of different manure treatment methods on dairy farms

Abstract The issue of manure disposal in dairy farms has long been a significant challenge afflicting the dairy farming industry, as manure poses various detrimental effects such as greenhouse gas emissions and land pollution. This remains an urgent concern for the industry to address. The traditional tank fermentation oxidation pond form of manure treatment and the new biogas power generation mode of manure treatment are currently widely employed in dairy farming enterprises. The evaluation and analysis of the environmental cost of new treatment modes should be conducted using scientific methods to determine which approach is more environmentally friendly. We selected two dairy farms with roughly the same number of dairy cows and the same management level, and the feed formula of the two dairy farms was basically consistent with the herd structure. Among them, the traditional tank fermentation manure treatment pasture, and the biogas power generation pasture. The Life Cycle Assessment (LCA) method of SimaPro software was used, and the software version was 9.0.0.48. In the life cycle assessment, we take into account the depletion of fossil energy, cement, metals, chemical products, electricity, heat, and mechanical pumps during the process of manure treatment. After accounting, the following conclusions are developed. During the whole life cycle of dairy farming, greenhouse gas emissions mainly fall into three types: methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O). CH4 accounts for 64% of the total emissions, which is mainly produced in the process of animal feeding, and a small part comes from manure treatment. CO2 accounts for 34% of the total emissions from the production of feed raw materials. The smallest proportion of transport and fossil energy consumption is N2O, which is mainly produced by manure treatment processes and accounts for 2% of total emissions. The environmental cost of the traditional tank fermentation oxidation pond is 17.6% greater than that of the new type of biogas power generation.