Life Cycle Assessment (LCA) of industrial milk production

Life Cycle Assessment (LCA) was applied to milk production and processing in a study of the Norwegian dairy industry. This method, LCA, is used to assess the potential environmental impact of a material, product or service throughout its entire life cycle, from the extraction of the raw materials, the production process, and the user phase, to the final disposal. The overall objective of this work was to establish a scientific base for environmental improvements in the Norwegian dairy industry in the future. Goals were also to work out ways to apply the LCA methodology to milk processing, to identify possibilities for improvements, and to investigate the influence of three key aspects in the dairy industry, the size of the dairy, the degree of automation of the dairy, and the transport distances. Two methods for carrying out an LCA of dairies were tested, and a method for allocation among various products in the dairy industry was suggested. The whole life cycle of milk and processing at three dairies was investigated. The agricultural phase was found to be the main hot spot in the life cycle of milk. Transport to dairies and to retailers was not found to have major influence. However, the consumer phase was important, due both to transport and to loss of milk. The smallest dairy was found to influence the environment the most. The lowest level of automation had the least influence on eutrophication. Milk packaging and cleaning of dairies were investigated in detail. Packaging was found to be of some importance, but the assumptions regarding waste management of them were found to be more important. Most of the emissions that lead to eutrophication stem from the cleaning processes in the dairies. Cleaning processes that combine low temperature and low concentrations of cleaning agents were found to be the best; however a clear-cut answer cannot be given due to the content of potentially toxic ingredients in the cleaning agents used by the cleaning methods requiring the least energy and with the lowest eutrophication potential. Dairy management was also found to be crucial. A qualitative assessment of the toxic substances was made. Sustainability should also be included in LCA; a study of how to include sustainability in LCA was carried out, and a qualitative method to combine LCA and the socio-ecological principles was also formed and recommended. The LCA methodology is well suited to identify hot spots and options for improvements in the dairy industry. LCA can be used to simulate both future situations and new technology, as a tool for future environmental investigations by means of the methods outlined in this study.