Despite discouraging economic conditions over the last two years, development of the world’s vast resources of oil shale continues to make progress.
Oil shale is reported from nearly 40 countries, with the largest deposits being located in the United States, Russia and China. Middle Eastern and North African resources also are large in aggregate.
Active commercial shale oil production occurs in Estonia, Brazil and China, with total global production of shale oil about 20,000 barrels per day. Informal current and future production numbers (figure 1) indicate that shale oil is unlikely to be a significant part of global production for a decade or more.
China has set aggressive goals for production over the next two decades, and the figures for the United States could be conservative, depending on the political environment.
The United States, Jordan, Israel and Morocco are nonproducing areas likely to see future shale oil production.
The United States, with over half the estimated world resources of oil shale, remains a central focus. The current political environment encourages caution, and companies are still conducting research, development and demonstration (RD&D).
The Bureau of Land Management, for example, has granted six RD&D leases and is reviewing three new applications. Other companies are working on state or private land in Utah and Wyoming.
Water use, widely touted as the Achilles heel of oil shale, is likely to be far less than that for biofuels, but western water rights still can be expected to be a thorny future issue. CO2 emissions perhaps 25-40 percent higher for some (not all) approaches than for conventional oil production also may drive technology development.
Other countries with little or no petroleum reserve may lead the United States in development – Jordan has multiple agreements with companies interested in oil shale production, and Morocco has awarded concessions or signed Memoranda of Agreement with Petrobras, Enefit and San Leon Energy to evaluate oil shale resources.
Estonian companies also are actively encouraging development in many locations.
Current industry research focuses on development and testing of techniques for extracting oil and minimizing environmental impacts of techniques in three main categories:♦ Mining and retorting.
Mining and retorting have produced shale oil for more than 100 years. New developments relate to increasing the efficiency and decreasing the impact of retort operation, such as in development of advanced fluidized bed reactors.
Research continues on the impacts of past production, and on utilization of spent oil shale and oil shale ash from burning of oil shale in power plants. Obvious applications involve use in cement and brick manufacture, but more advanced techniques involve extraction of various constituents from the material.
The Fushun Mining Company (China) has set as an objective of no net waste products from oil shale production.♦ In situ heating and extraction.
In situ extraction is the focus of intensive research to develop a method to heat and pyrolyze kerogen-rich rocks underground and efficiently extract the oil and gas from the formation. Shell has led in this area, but ExxonMobil, Total/AMSO, Chevron and others are investigating different processes.
In situ heating takes longer (on the scale of years), but pyrolysis occurs at lower temperatures, and additional reaction at depth leads to a lighter oil with a larger gas fraction. Less secondary processing to meet refinery requirements is needed.
Research on in situ processes and on processing the resulting material continues at companies developing these methods, but results are generally proprietary. Symposium presentations have described general results in containment, heating, extraction, refining and reclamation.♦ In-capsule extraction.
In-capsule extraction is being pursued by Red Leaf Resources of Cottonwood Heights, Utah. It involves mining of oil shale, encapsulation in a surface cell akin to a landfill, heating and extraction of the products, and final sealing of the exhausted retort.
The premier opportunity to catch up with global developments in oil shale will be the 30th Oil Shale Symposium, held at the Colorado School of Mines Oct. 18-20 (with a field trip to western Colorado and eastern Utah on Oct. 21-22).
Register for the symposium at http://outreach.mines.edu/cont_ed/oilshale/?CMSPAGE=Outreach/ cont_ed/oilshale.
The Energy Minerals Division (EMD), a division of AAPG, is dedicated to addressing the special concerns of energy resource geologists working with energy resources other than conventional oil and gas, providing a vehicle to keep abreast of the latest developments in the geosciences and associated technology. EMD works in concert with the DEG to serve energy resource and environmental geologists.