Responsible Oil Sands Development
Syncrude is one of the largest producers of crude oil from oil sands. Our oil production facility has the capacity to produce around 15% of Canada's total oil requirements.
To do this, we surface mine oil sand, extract the raw oil known as bitumen from the sand using water-based processes and upgrade that bitumen into a high quality, light sweet crude oil through fluid coking, hydroprocessing, hydrotreating and reblending.
Our final product, Syncrude Sweet Premium (SSP), is sent by pipeline to Edmonton area refineries and to pipeline terminals which ship it to refineries in Canada and the United States. Once the product leaves our plant site, transportation and marketing become the responsibilities of our joint venture participants. Bitumen is not shipped from our operations.
The Syncrude operation is comprised of five major areas or processes: Mining, Extraction, Upgrading, Utilities and Reclamation. These areas are supported by ongoing Research and Development.
The process of turning oil sand into crude oil begins with mining the resource. Because the oil sand found on Syncrude’s leases is not deeply buried, surface mining is the most viable method of recovery.
First, muskeg and overburden are removed and set aside for reclamation activities. The exposed oil sand is then scooped into trucks and dumped into double-roll crushers to break up the big pieces.
Next, the oil sand is fed into a cyclofeeder where warm water and steam are added to create a slurry. This is then pumped by hydrotransport pipelines to extraction facilities. In the pipeline, the bitumen begins to separate from the sand and water.
Extraction is where bitumen is separated from the sand. The slurry is fed into Primary Separation Vessels (PSVs), where the bitumen floats to the surface as froth. Tumblers are also used.
Before heading to the Upgrader, the froth is diluted with naphtha and put into either inclined plate settlers or through centrifuges to remove water and solids. Over 99% of the naphtha is recovered and recycled back to the extraction plant.
Middlings, which remain suspended in the middle of the vessel, are fed through smaller versions of the PSVs to recover additional bitumen.
The remaining material consists of sand, water, clay, fine silts and residual bitumen, and is known as tailings. Tailings are pumped by pipeline to one of several settling basins on site. These settling basins, or tailings ponds, are the source of the recycled water used in the bitumen extraction process. Over 85% of the water used at Syncrude is from these facilities. We are also actively pursuing a suite of technologies which will assist us in reclaiming tailings more quickly.
We regularly achieve bitumen recovery rates exceeding 90%. Incremental increases can translate into significant economic and production benefits, while reducing the amount of bitumen that enters the tailings ponds. Specific initiatives are underway to improve our processes and develop the new generation of extraction technologies.
The Aurora mine – located about 40 kilometres north of our Mildred Lake site – is a model for oil sands efficiency and smart energy use. Hot water, reclaimed from waste heat produced at the Mildred Lake Upgrader, is sent via pipeline to the Aurora mine where it is used to extract the bitumen from the oil sand. This results in a substantial reduction in the energy that would otherwise be required to heat the water. The cooler water is then returned, along with the bitumen, to the Upgrader at Mildred Lake. Here, the bitumen in processed into crude oil and the water reheated and again returned to the Aurora.
The Syncrude upgrading process converts converts bitumen into hydrocarbon streams – naphtha, light gas oil (LGO) and heavy gas oil (HGO) – that are blended to create our high quality, light, low sulphur crude oil.
The first step in the upgrading process is to remove the naturally occurring light gas oil component of bitumen and to recover the diluent naphtha. This is done in the three diluent recovery units, which operate much like an atmospheric distillation unit in a conventional refinery.
The light gas oil stream is sent to the hydrotreaters, the diluent naphtha is recycled to the Extraction plant and the bottoms – atmospheric topped bitumen – is predominantly fed to the Vacuum Distillation Unit (VDU), with a modest amount going directly to the conversion units. The VDU removes all of the remaining light and heavy gas oils, directing these streams to the hydrotreaters. The bottoms from the VDU - vacuum topped bitumen – are fed to the conversion units: three fluid cokers and one hydrocracker (LC-Finer).
The cokers are thermal conversion units that crack long chain bitumen molecules into more valuable short chain molecules – heavy gas oil, light gas oil and naphtha. The fluid coking process is a continuous operation where fluidized coke particles are transferred back and forth between the reactor and burner vessels. A portion of the coke produced in this process is transferred to the burner to provide heat for the thermal cracking process. The LC-Finer is an ebulated bed process that uses catalyst and hydrogen to convert bitumen into gas oils and naphtha.
Intermediate naphtha and gas oil products are processed in a variety of hydrotreater units. These units operate at high pressure and use fixed bed catalytic reactors to treat the product and remove sulphur, nitrogen and other impurities. The resulting crude oil is a blend of naphtha, light gas oil and heavy gas oil.
There are numerous other units in Upgrading that support the operation. These include hydrogen units that supply hydrogen to the hydrotreaters, environmental units that treat water and gas streams, and sulphur recovery units. There is also a flue gas desulphurization unit (FGD) that processes the burner flue gas from our third coker to remove sulphur and reduce emissions. The FGD is linked to an offsite fertilizer plant that prepares a marketable product from the recovered sulphur.
The utilities operation supplies steam, electricity, air, water and nitrogen for our operations.
Fuel for utility steam and power production is primarily from coker burner overhead gas and plant fuel gas. At the Aurora site, natural gas is also used as a source of fuel.
Steam is generated by nine boilers and two “once-through” steam generators which recovers exhaust heat from our gas turbines.
Electricity is produced by 10 generators (six steam turbines and four gas turbines) with a total installed capacity of over 500 megawatts.
Air is supplied by four high speed centrifugal air compressors, for plant instrumentation and general use.
Water is produced by ten demineralizer trains for the Utility boilers and heat recovery boilers in Upgrading. Water is also continuously cycled through four cooling towers which keep plant cooling water at approximately 20º C. In addition, additional cooling water is recycled through the extraction process at an average rate of 13,500 m3/hr. This water is sourced from the tailings ponds. Click here for more information on our water use and conservation.
Nitrogen is both produced – in an air fractionation plant – and purchased.
Reclamation is a process that begins long before a shovel is even first put in the ground. Mine planning occurs years in advance which helps to not only chart the mine’s progression, but to also guide reclamation and map which elements will constitute the final restored landscape.
There are a number of major steps in the reclamation process through to official certification:
◾Long-range reclamation plans – Developed decades in advance, and approved by government with input from stakeholders.
◾Placement of landform foundation material – Overburden,sand and/or tailings fills up former mines.
◾Landscape design –Geotechnical engineers guide the design of the landscape.
◾Placement of top soil – Muskeg, peat and organic matter from the forest floor are moved from future mine areas and placed on land undergoing reclamation.
◾Re-vegetation and reforestation – Vegetation specialists manage native plants, shrubs and trees to recreate diverse boreal forest ecosystems.
◾Monitoring – Scientists keep close watch to ensure the health of the reclaimed area.
◾Certification – When access to the reclaimed area is no longer required for our operations, and regulators determine the land is healthy, productive and reclaimed to their satisfaction, it can be certified. The land is then available to be released back to the Province of Alberta.
Syncrude is the only oil sands operation to have received certification for permanently reclaimed land. In 2008, certification was granted by the Alberta Government for the Gateway Hill upland forest area.