Fuels from Oil Shale and Tar Sands Nature of resource Size What’s required to produce/process Issues
Atomic H/C Ratios From Wiser, 2000 Arrow in direction of… Solid-liquid-gas Ease of transport Less solids pollution Less air contamination Smaller viscosity Oil from shale, tar sand Note: scale is a continuum
Classification Based on Viscosity…. Roughly…. At room temperature < 10 cp is a light oil - < 10,000 is a heavy oil < 10 6 is a tar sand oil > 10 6 is bitumen
Classification Based Non-organic Sediment…. H/C Ratio % Non-Organic Sediment Coal Nat. Gas Crude Tar Sands Oil Shale
The Canadian Oil Sands The US consumes annually 7 x 10 9 bbl oil The Alberta Canada (Athabascan) oil (tar) sands contain ~2 x bbl oil, recoverable at current price, matching the recoverable reserves of Saudi Arabia The 2005 Albertan tar oil production was 4 x 10 8 bbl
Economic History of the Canadian Oil Sands Commercial production of oil from the Athabasca oil sands began in 1967, when Suncor opened its first mine. Development was soon inhibited by declining world oil prices. The second mine, operated by Syncrude, began operating in As the price of oil subsided after the Arab oil embargo, the plug was again pulled on new developments. The third mine, operated by Shell Canada started operating only in With the oil price increases, and the production cost being $ 35-$ 38, the existing mines have been greatly expanded and new ones are being planned
Where Will the Tar Oil Go? An agreement has been signed between PetroChina and Enbridge to build a 400,000 barrel-per-day pipeline from Edmonton, Alberta to the west-coast port of Kitimat BC to export synthetic crude oil from the oil sands to China plus a 150,000 bpd pipeline running the other way to import condensate to dilute the bitumen so it will flow. Sinopec, China's largest refining and chemical company, and China National Petroleum Corporation have bought shares in major oil sands companies India invested $1 billion in the Athabasca Oil Sands in Four Indian companies are involved
The Oil Sand Crude: Bitumen
Tar Sands…. Nature: Highly viscous hydrocarbon found with 80-90%non-organic material Size: large deposits in California, Alberta, Venezuela Conventional mining/processing In situ injection of steam Issues…. - Energy intensive - Several commercial processes - Cogeneration helps - Low quality crude oil
Shale Oil Oil shales are rocks rich in organic matter (kerogen) The oil is derived through retorting, i.e. pyrolysis in the absence of air, at °C The worldwide reserves of oil shale are estimated at 2.6 trillion barrels of recoverable oil trillion barrels are in the US Oil shale is can be burned as is, but it is a low-grade fuel Oil shale is currently mined in Estonia, Brazil and China
History of US Shale Oil On-Again, Off Again 1964 Colony oil shale project of Tosco, Sohio and Cleveland Cliffs 1972 Colony oil shale project halted after 270,000 bbls were produced. Occidental Petroleum conducts in-situ oil shale experiments at Logan, WA. Shell researches Piceance Creek in-situ steam injection process for oil shale. Oil drops $ 20/bbl 1974 Unocal develops new “Union B” retort process; Shell and Ashland join Colony Project. Oil prices increase, at $41/bbl 1976 Unocal begins planning commercial scale plant at Parachute Creek to be built when investment is economical 1977 Oil prices drop. Superior Oil abandons plan for Meeker oil shale plant planned since Shell, Ashland, Cleveland Cliffs and Sohio sell interests in Colony to ARCO and Tosco; Shell sells leases to Occidental and Tenneco Exxon buys Arco’s Colony interest and in 1981 starts Colony II construction, designed for 47,000 bbl/d by the Tosco II retort process; Unocal plans Long Ridge bbl/d plant applying “Union B” retort; Amoco Rio Blanco produces 1,900 bbls of in-situ oil
1981 Exxon begins to build Battlement Mesa company town for oil shale workers; Second Rio Blanco in-situ retort demonstration produces 24,400 bbls of shale oil 1982 Oil demand falls and crude oil prices collapse; Exxon closes Colony II due to cost and poor demand; Shell continues in-situ experiments at Red Pinnacle and labs through Congress abolishes Synthetic Liquid Fuels Program 1987 Shell purchases Ertl-Mahogany and Pacific tracts in Colorado; Exxon sells Battlement Mesa for retirement community 1991 Occidental closes C-b tract project before first retort begins operation; Unocal closes Long Ridge after 5 MM bbls and 10 years for operational issues and losses Shell tests in-situ heating on Mahogany property; defers further work on economic basis Shell returns to Mahogany with expanded in-situ heating technology research plan (ongoing) History of US Shale Oil
Oil Shale…. Nature: Semi-solid hydrocarbon (kerogen) found with 80-90%non-organic material Size: enormous….130 billion bbl of oil equivalent in Green River shale (Rocky Mountains)..US has 62% of world supply To produce: bring to surface and retort (heating to 400 deg C) converts kerogen to crude Issues…. - Excavating issues - Generate large amount of depleted shale - Energy intensive - No commercial processes
In-Situ Methods True In Situ (TIS) - Fracture oil shale - Inject air - Ignite shale Modified In Situ (MIS) - Mine above or below targeted shale deposit - Fill void with rubbished shale - Ignite shale In Situ Conversion Process (ICP) - Drill shafts into the oil-bearing rock - Drop heaters down the shafts - Cook the rock until the hydrocarbons boil off
Schematic of In Situ Retorting…. From Shepherd and Shepherd, 1998
Shell’s ICP Technology
“Freeze wall” technology - Drill shafts 8-12 ft apart around perimeter of productive site - Put in piping - Pump refrigerants through - Freezes water in the ground around the shafts - Forms a 20- to 30-foot ice barrier around the site
Shell’s ICP Technology
ICP Advantages Reduced environmental impact Reduction of costs in mining, transportation, and crushing Favorable energy balance More desirable grade Greater production depths Extraction from leaner shale Quick production drop
ICP Disadvantages Large amount of water required Time Reliable heater technology Heater durability
Economic Viability Point of ProfitEROEI (Energy Returned on Energy Invested) Ex Situ$70 – 95 per barrel 0.7 – 13.3 ICP> $30 per barrel 3-4