Green Diesel: A Second Generation Biofuel

Abstract

Environmentally-conscious design of processes and products is increasingly viewed as an important strategy in the sustainable development of new refining and chemical processes. This paper discusses a new process technology developed by UOP and Eni S.p.A; the UOP/Eni EcofiningTM process to produce green diesel from vegetable oil. This novel process utilizes catalytic saturation, hydrodeoxygenation, decarboxylation and hydroisomerization reactions to produce an isoparaffin-rich diesel fuel from renewable feedstock containing triglycerides and fatty acids. The resultant biofuel product has a high cetane value, a lower gravity, good cold flow properties and excellent storage stability. Green diesel is completely compatible for blending with the standard mix of petroleum-derived diesel fuels, thus providing significant value to the refiner. The process for producing green diesel operates at mild operating conditions and integrates well within existing petroleum refineries. In contrast to fatty acid methyl esters, where fuel properties depend on feed origin and process configuration, green diesel product is independent of feed origin and the fully deoxygenated biofuel is readily blended with conventional diesel fuel. A life cycle assessment (LCA) of this promising new biofuel production technology has been undertaken to quantify the intrinsic benefits of green diesel production over the current practice of converting various forms of lipids to fatty acid methyl esters. This paper will describe the technology, discuss the results of the LCA study and summarize the advantages this new technology can offer over other processing routes.

Placing microalgae on the biofuels priority list: a review of the technological challenges

“…The resulting product was comparable in properties to ultra-low sulphur diesel and superior to oxygenated biodiesel. As part of the study by Kalnes et al (2007), a life cycle analysis was undertaken; green diesels were found to have higher net energy balances than petroleum diesel and biodiesel, which translate to lower fossil fuel inputs during their production and increased sustainabilityan important point often overlooked. They also lead to considerably lower greenhouse gas emissions per energy equivalent, as the sulphur content is negligible, thereby reducing sulphur oxide emissions compared with petroleum diesel, being slightly less than comparable amounts of biodiesel.…”

Biodistillate Transportation Fuels 3 - Life Cycle Impacts

“…Other coproducts such as naphtha or propane may be produced in renewable diesel manufacturing involving catalytic hydroprocessing. (36) Common practice in LCA modeling is to allocate some of the energy and emissions produced during the fuel life-cycle to these co-products since they can replace other similar products in the market. The following methods of allocation are commonly used (37,38,39) :…”

Catalytic Hydrodeoxygenation of Fatty Acids for Biodiesel Production

“…Thus, the alternative renewable energy sources, which are able to provide stable long-term energy production, are of great importance [1].…”

“…The analysis of the methods of estimation and ways of decrease in negative ecological influence of diesel engines on environment shows that now the basic direction is the use of alternative fuels [2]. Nowadays, the following types of biofuels are the most widely used ones: biogas, bioethanol, biodiesel, biobutanol [1].…”