Life Cycle Assessment Of Ammonium Phosphate Production In China

The Ammonium Phosphate plays a very important role in China which accounted for 76.61% of the total production of phosphate fertilizer. In 2014, the Ammonium Phosphate production was 13.1 million tons in China. The Ammonium Phosphate is widely used in agriculture, animal husbandry, forestry, and fertilizer chemical industry plays. However, the Ammonium Phosphate production consume large amounts of resources and energy, and produce large quantities of phosphogypsum, heavy metals, radioactive substances and other pollutants to the atmosphere, soil and water which have the serious pollution to the environment.Life cycle assessment (LCA) as an effective environmental management tool which scientifically and comprehensively evaluate the potential environmental effects generated by the product or production activities throughout the life cycle. In present study, the LCA was used to evaluate the environmental burden caused by Ammonium Phosphate production. To evaluate environmental effects generated by Ammonium Phosphate production at macro level, a hybrid LCA combined with the national and provincial statistics data was conducted in the present study. The aim of this study is not only to quantify the life cycle environmental impact of Ammonium Phosphate production in China, but also to provide scientific theory and database for decision making on establishment, reconstruction, expansion, or technological transformation of Ammonium Phosphate industries.Specifically, life Cycle Inventory of Ammonium Phosphate production was built based on company’s primary data and Chinese Process-based Life Cycle Inventory database. ReCiPe method was chosen to evaluate the environmental effects caused by Ammonium Phosphate production. Normalization was applied in present study with the aim to identify the key categories that contribute to the overall environmental burden. Additionally, this study identified the key factors (i.e., substance and processes) contributed to the identified key categories. Finally, to add the credibility of this research, sensitivity and uncertainty analysis were conducted in the present study.For the Ammonium Phosphate production scenario, the midpoint life cycle impact assessment results showed that the dominant categories were terrestrial acidification, particulate matter formation, marine ecotoxicity and fossil depletion. The phosphoric acid stages and phosphogypsum landfill stage were the key processes. The dominant substances in terrestrial acidification category were ammonia, nitrogen dioxide and sulfur dioxide, for marine ecotoxicity, they were copper, vanadium, nickel, cobalt, mercury, zinc, beryllium and bromine. Similarly, nitrogen dioxide, particulate matter and sulfur dioxide played an important role to the particulate matter formation, whereas, the use of coal, natural gas and crude oil were the dominant contributors to fossil depletion score. Sensitivity analysis of LCA method results showed that evaluation results obtained via ReCiPe were reliable in present study.In 2014, the overall environmental burden generated from Ammonium Phosphate in China in the categories of climate change, terrestrial acidification, particulate matter formation, marine ecotoxicy and fossil depletion were 1.90 × 1011 kg CO2 eq, 4.67 × 109kg SO2eq,1.29 × 109 kg PM10 eq,1.46 × 108kg 1,4-DB eq and 5.76 × 1010 kg oil eq, respectively. Hubei, Yunnan and Guizhou provinces had the highest Ammonium Phosphate yield and the most dominant environmental impact which because of the large amounts of phosphate rock reserves in these areas.Above results indicate that improving the raw material and phosphate fertilizer consumption efficiency, optimizing the utilization of phosphogypsum, promoting variety ways of phosphogypsum utilization, developing low-concentration phosphate fertilizer, and choosing the best phosphate fertilizer fertilization rate are the effective methods of minimizing the overall environmental impacts cause by Ammonium Phosphate production.