Artificial lake to replace Syncrude Oilsands Mine

Jim Lorentz

In 2012, Syncrude will finish a pit where it has been  mining oil sands over the last two decades. In its place, the company will build a huge experimental lake it is calling Base Mine Lake.
As Syncrude’s technology development officer Jim Lorentz explains, dried tailings left over from oil sands production will form the lake bottom.
“That is where we add a layer of mature fine tails and then we cap it with a freshwater cap. The lake is designed to have latoral zones which are the shallow zones where some of the vegetation and stuff you see in lakes grow from, allowing a lot of sunlight to permeate through and encouraging biological activity.
“The belief is after 10 years, we would have enough biological activity at the point where we could start introducing more complex life, like fish and amphibians, those kind of things.”
According to Lorentz, Base Mine Lake builds on the success of a previous pilot program which involved the construction of a four-acre lake. He stresses future monitoring of the aquatic environment at will be extensive. √

~ Cheryl Croucher

Spin Dried Tailings

Tailings in oils sands parlance refers to the material leftover at the tail end of production… after the oil has been separated from the sand.
At Syncrude, this collection of sand, clay and water is pumped down a pipeline into artificial ponds. Over time, the particles of sand and clay settle to the botton of these tailings ponds, and the water is recycled back into the plant for reuse in the oil sand separation process.
According to technology developent officer Jim Lorents, Syncrude is piloting a new system to speed up that process. It uses centrifugal force, drying the tailings much like the spin dry cycle removes water from your laundry.
“We’re trying to dry those solids using mechanical energy and increase basically what gravity has to offer, ” he says. ” The machines we’re talking about are commercially available. We’re talking about a metre diameter by about three metres to four metres long, and multiples of them in parallel. We’re talking about improving the gravitational force from one gravitational force to 200 plus gravitational forces. So that should reduce the settling time by about 200 times”.
As Lorentz explains, the spin-dried material or “cake” would be left to dry for a season. Then is could be used in wet or dry landscape reclamation.

~ Cheryl Croucher