Environmental impact assessment of a nitrogenous fertilizer (CAN 27% N) production in the Algerian plant

Abstract

This paper aims to assess the environmental impact of a fertilizers produced in Algeria. The Functional Unit chosen for this study is One ton of CAN at 27% of Nitrogen. In first, a detailed inventory of energy and materials flows for all life cycle of the product has been completed, and primary data collection was executed at the production facilities located in Algeria and completed by “Ecoinvent” database. Particularly, the energy performance and Greenhouse Gases (GHG) of the product (CAN 27% of N) were assessed. Evaluation of the impact was carried using GEMIS 4.7 software according to life Cycle Assessment (LCA) method and expressed with the “CML” method. Results have focused on the assessment of energy efficiency (Cumulative Energy Requirement (CER)) and of GHG emissions quantification. Global Warming Potential (GWP) is very significant due to the GHG emission of 2.46 t CO2 eq/FU of CAN. CO2 is the most important GHG emission factor with 1.21 T/T of CAN. The results show that the Algerian fertilizers production process is characterized by its high energy requirement (13.49 GJ/T of CAN), this request higher than the world average. The overconsumption in the Algerian process increases the cumulative energy requirement. Two factors contribute to explain this overconsumption of energy in the Algerian fertilizers production process, the first is related to the multiple restarts of the plant following the failures that usually occur. The second factor is the efficiency of the catalytic reaction in the upstream processes (NH3 and HNO3).