Unconventional Heavy Oil Growth and Global Greenhouse Gas Emissions

Enormous global reserves of unconventional heavy oil make it a significant resource for economic growth and energy security; however, its extraction faces many challenges especially on greenhouse gas (GHG) emissions, water consumption, and recently, social acceptability. Here, we question whether it makes sense to extract and use unconventional heavy oil in spite of these externalities. We place unconventional oils (oil sands and oil shale) alongside shale gas, coal, lignite, wood and conventional oil and gas, and compare their energy intensities and life cycle GHG emissions. Our results reveal that oil shale is the most energy intensive fuel among upgraded primary fossil fuel options followed by in situ-produced bitumen from oil sands. Lignite is the most GHG intensive primary fuel followed by oil shale. Based on future world energy demand projections, we estimate that if growth of unconventional heavy oil production continues unabated, the incremental GHG emissions that results from replacing conventional oil with heavy oil would amount to 4–21 Gt-CO₂eq GtCO₂eq over four decades (2010 by 2050). However, prevailing socio-economic, regional and global energy politics, environmental and technological challenges may limit growth of heavy oil production and thus its GHG emissions contributions to global fossil fuel emissions may be smaller

Real time monitoring of biofilm development under flow conditions in porous media

<div><p>Biofilm growth can impact the effectiveness of industrial processes that involve porous media. To better understand and characterize how biofilms develop and affect hydraulic properties in porous media, both spatial and temporal development of biofilms under flow conditions was investigated in a translucent porous medium by using <i>Pseudomonas fluorescens</i> HK44, a bacterial strain genetically engineered to luminesce in the presence of an induction agent. Real-time visualization of luminescent biofilm growth patterns under constant pressure conditions was captured using a CCD camera. Images obtained over 8 days revealed that variations in bioluminescence intensity could be correlated to biofilm cell density and hydraulic conductivity. These results were used to develop a real-time imaging method to study the dynamic behavior of biofilm evolution in a porous medium, thereby providing a new tool to investigate the impact of biological fouling in porous media under flow conditions.</p> </div

Comparison of Electronic and Physicochemical Properties between Imidazolium-Based and Pyridinium-Based Ionic Liquids

To compare 1-butyl-3-methylimidazolium ([BMIM]⁺)- and 1-butyl-3-methylpyridinium ([BMPy]⁺)-based ionic liquids (ILs) and investigate the influence of intramolecular and intermolecular interactions on physicochemical properties, a systematic study was performed on the electronic structures and physicochemical properties of [BMIM]⁺ tetrafluoroborate ([BMIM]­[BF₄]), [BMIM]⁺ hexafluorophosphate ([BMIM]­[PF₆]), [BMIM]⁺ hydrogen sulfate ([BMIM]­[HSO₄]), [BMIM]⁺ methylsulfate ([BMIM]­[MSO₄]), [BMIM]⁺ ethylsulfate ([BMIM]­[ESO₄]), [BMPy]⁺ tetrafluoroborate ([BMPy]­[BF₄]), [BMPy]⁺ hexafluorophosphate ([BMPy]­[PF₆]), [BMPy]⁺ hydrogen sulfate ([BMPy]­[HSO₄]), [BMPy]⁺ methylsulfate ([BMPy]­[MSO₄]), and [BMPy]⁺ ethylsulfate ([BMPy]­[ESO₄]) using density functional theory and molecular dynamics simulation. The results reveal that aggregation behavior exists in [HSO₄]⁻- and [ESO₄]⁻-based ILs, and the differences between their densities and self-diffusion coefficients are smaller when there is an aggregation effect in ILs. A dimer is formed by two strong hydrogen bonds between two [HSO₄]⁻ anions in [HSO₄]-based ILs, and the existence of hydrogen bonds in ILs increases density and decreases the self-diffusion coefficient. The intermolecular interaction strength of [BMIM]⁺-based ILs is stronger than that of [BMPy]⁺-based ILs