In recent years, hydraulic fracturing and horizontal drilling have been applied to extract crude oil from tight reservoirs, including the Bakken formation. There is growing interest in understanding the greenhouse gas (GHG) emissions associated with the development of tight oil. We conducted a life cycle assessment of Bakken crude using data from operations throughout the supply chain, including drilling and completion, refining, and use of refined products. If associated gas is gathered throughout the Bakken well life cycle, then the well to wheel GHG emissions are estimated to be 89 g CO 2 eq/MJ (80% CI, 87-94) of Bakken-derived gasoline and 90 g CO 2 eq/MJ (80% CI, 88-94) of diesel. If associated gas is flared for the first 12 mo of production, then life cycle GHG emissions increase by 5% on average. Regardless of the level of flaring, the Bakken life cycle GHG emissions are comparable to those of other crudes refined in the United States because flaring GHG emissions are largely offset at the refinery due to the physical properties of this tight oil. We also assessed the life cycle freshwater consumptions of Bakken-derived gasoline and diesel to be 1.14 (80% CI, 0.67-2.15) and 1.22 barrel/barrel (80% CI, 0.71-2.29), respectively, 13% of which is associated with hydraulic fracturing.life cycle assessment | unconventional resources | petroleum | hydraulic fracturing | flaring

A petroleum refinery model, Petroleum Refinery Life-cycle Inventory Model (PRELIM), that estimates energy use and CO emissions was modified to evaluate the environmental and economic performance of a set of technologies to reduce CO emissions at refineries. Cogeneration of heat and power (CHP), carbon capture at fluid catalytic cracker (FCC) and steam methane reformer (SMR) units, and alternative hydrogen production technologies were considered in the analysis. The results indicate that a 3-44% reduction in total annual refinery CO emissions (2-24% reductions in the CO emissions on a per barrel of crude oil processed) can be achieved in a medium conversion refinery that processes a typical U.S. crude slate obtained by using the technologies considered. A sensitivity analysis of the quality of input crude to a refinery, refinery configuration, and prices of natural gas and electricity revealed how the magnitude of possible CO emissions reductions and the economic performance of the mitigation technologies can vary under different conditions. The analysis can help inform decision making related to investment decisions and CO emissions policy in the refining sector.

This study updates the Petroleum Refinery Life Cycle Inventory Model (PRELIM) to provide a more complete gate-to-gate life cycle inventory and to allow for the calculation of a full suite of impact potentials commonly used in life cycle assessment (LCA) studies. Prior to this update, PRELIM provided results for energy use and greenhouse gas emissions from petroleum refineries with a level of detail suitable for most LCA studies in support of policy decisions. We updated the model to add criteria air pollutants, hazardous air pollutants, releases to water, releases to land, and managed wastes reflecting 2014 reported releases and waste management practices using data from the U.S. Environmental Protection Agency Greenhouse Gas Reporting Program, National Emissions Inventory, Discharge Monitoring Reports, and Toxic Release Inventory together with process unit capacities and fuel consumption data from the U.S. Energy Information Administration (U.S. EIA). The variability of refinery subprocess release factors is characterized using log-normal distributions with parameters set based on the distribution of release factors across facilities. The U.S. EPA Tool for the Reduction and Assessment of Chemical and Environmental Impacts life cycle impact assessment (LCIA) method is used together with the updated inventory data to provide impact potentials in the PRELIM dashboard interface. Release inventories at the subprocess level enable greater responsiveness to variable selection within PRELIM, such as refinery configuration, and allocation to specific refinery products. The updated version also provides a template to allow users to import PRELIM inventory results into the openLCA software tool as unit process data sets. Here we document and validate the model updates. Impact potentials from the national crude mix in 2014 are compared to impacts from the 2005 mix to demonstrate the impact of assay and configuration on the refining sector over time. The expanded version of PRELIM offers users a reliable, transparent, and streamlined tool for estimating the effect of changes in petroleum refineries on LCIA results in the context of policy analysis.

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The catalytic pyrolysis of low‐rank coal (boundary dam lignite coal) for production of valuable chemical compounds, such as aromatics, over zeolites has been investigated with promising results. In this study, primarily zeolites ZSM‐5 (zeolite socony mobil‐5) and LTL (Linde type L) were successfully synthesized by a direct hydrothermal method without using any templates, known as structure directing agents (SDAs). Various analysis methods were employed to characterize the parent and modified zeolites before catalyzing the pyrolysis of coal. The H‐form of zeolite LTL showed the best performance for phenol, methane, and hydrogen formations in slow pyrolysis of coal at a temperature range of 400–600 °C and heating rate of 5° C/min. The effect of zeolite LTL potassium content on changing the coal decomposition path is suggested to enhance the production of these compounds along with cracking activity of the acid sites of the zeolites.