Comparative analysis of economic and environmental factors in green urea production

Abstract

Due to increased strain to satisfy food needs brought on by the global population growth, fertilizers are widely used to increase agricultural yields. The most commonly used fertilizer in the world, urea, has substantially intensified agricultural output. However, the conventional method of producing urea is mostly reliant on fossil fuels, which contributes to considerable greenhouse gas (GHG) emissions and exacerbates climate change. Concerns about environmental sustainability are growing as the demand for urea keeps increasing. As a result, new technologies are being developed to create urea, which are said to have less of an impact on the environment than traditional ones. Examining current urea manufacturing methods, evaluating various technical avenues, and contrasting their effects on the environment and the economy were the objectives of this master's thesis. The investigation took into account the established-, hybrid-, green-, and progressive-, pathways with variations in the production water, methane (CH4), and electricity sources. Global Warming Potential (GWP), Primary Energy Use (PEU), and cost were the primary metrics that were examined. A cradle-to-gate life-cycle impact assessment (LCIA) was employed for the environmental evaluation, and material flow cost accounting (MFCA) was applied for the cost analysis. The traditional urea production process was compared with the alternative green, hybrid, and advanced technical paths. The utilization of low-emission power sources, like the Swedish and European grids, and the production of byproducts were the primary reasons why the results showed that these other paths might lower GWP or PEU values. However, the study's parameters did not allow for the simultaneous decrease of GWP, PEU, and costs. The results underline the difficulties in using alternative methods to outperform traditional technologies and the necessity of better technological integration and by-product usage through industrial symbiosis. In the end, the study emphasizes how crucial it is to balance the trade-offs between financial costs and environmental advantages when selecting technical avenues for urea production.