1.
Oilsands Technologies and Offsets
Note; This information contained is quoted from David W. Devenny, PhD, P.Eng,
P Geol (The Rock Doctor) Part AB Report, (A Screening Study of Oilsands Tailings
Technologies and Practices) Prepared for Alberta Energy Research Institute
(AERI Contract 2008 0326)
Fast Facts:
Offsets are used as a identifier for Oilsands technologies that
address “Mature fine tailings” (MFT’s) and Fresh tailings (FT’s)
to complete the intent to halt accumulation or only part
thereof:
Fiscal Terms For Oilsands
Individual components of the fiscal regime are Alberta royalty,
capitol investment incentives and federal and provincial income
tax.
Alberta Royalty is the greater of a specified percentage of net
profit, or percentage of gross income.
A dollar of profit is shared is shared according to fiscal
terms. Depending on the price of Oil. Fiscal sharing leaves the
developer with $0.45 to $0.56 from each dollar of profit,
government receive the rests. This will occur in the reverse
when expenditures are made.
Regulating Oilsands
2004 ERCB and the Canadian Environmental Assessment Agency
identified several long-term objectives respecting tailings
management:
1. To minimize and eventually eliminate long-term storage of
fluid tailings in the reclamation landscape
2. To create a trafficable landscape at the earliest
opportunity to felicitate progressive reclamation
3. To eliminate or reduce containment of fluid tailings in an
external tailings disposal area during operations
4. To reduce stored process-affected waste water volumes on
site
5. To maximize intermediate process water recycling to
increase energy efficiency and reduce fresh water impact
6. To minimize resource sterilization associated with tailings
ponds
7. To ensure that the liability for tailings is managed through
reclamation of tailings ponds

2.
Oilsands Technologies and Offsets
Note; This information contained is quoted from David W. Devenny, PhD, P.Eng,
P Geol (The Rock Doctor) Part AB Report, (A Screening Study of Oilsands Tailings
Technologies and Practices) Prepared for Alberta Energy Research Institute
(AERI Contract 2008 0326)
2009 of February the ERCB issued “Directive 074” it requires
Oilsands operators to solidify increasing amounts of fluid
tailings each year, report on fines management and report on
the performance of each tailings facilities annually.
Extraction of Oilsands Ore
Suncor and Syncrude add caustic soda in extraction to
felicitate bitumen removal. Caustic soda also disperses clay,
that adds to the volume of fluid tailings created.
Albian Sands proposed to operate extraction without adding
dispersing agents. For the reason of anticipated superior
performance in tailings that are denser, rapidly settling
tailings and faster water clarification. However the requirement
for the project was to add sodium citrate a dispersing agent to
aid bitumen extraction that inherently adds additional tailings.
Traditional extraction produces waste that can be pumped. The
upper limit for the strength of pumpable waste is 100kPa,
however that’s 1% of the strength desired for reclamation.
Taiings Pond Behaviour
The tailings ponds can be prepared to large vessel that
clarifies water and provides storage for fine-grained deposits.
Material that enters the tailings pond consists of water,
unrecovered bitumen, and silt, Clay dissolved chemicals
dissolved chemicals, solvent losses, and process aids.
The waste slurry entering the tailings ponds is quite dilute, with
a typical solid content of 5% to 10%. Suspended solids slowly
settle leaving clear water behind. As the solids the suspension
becomes denser and particles interfere with each other. This
Transition zone extends to the depth of few meters, finally the
density reaching 30% solids, repulsive forces between clay
particles prevent further densification. The deposit at that
stage is known as Mature Fine Tailings or MFT’s.

3.
Oilsands Technologies and Offsets
Note; This information contained is quoted from David W. Devenny, PhD, P.Eng,
P Geol (The Rock Doctor) Part AB Report, (A Screening Study of Oilsands Tailings
Technologies and Practices) Prepared for Alberta Energy Research Institute
(AERI Contract 2008 0326)
Volume of Tailings Ponds
Forecasting tailings volumes so storage facilities can be
constructed and ready to store expected tailings.
Fast facts:
Waste volumes for Base case and all thicker cases MFT’s is
considered to be end product, volume of waste created on
average 1.3 cubic metres per cubic metre of Ore for all cases,
seventy-five % is sand 25% of that is tailings ponds.
Base Case: 1.320 m3
Thickner1 WO cyclones: 1.301 m3
Thickner1 W cyclones: 1.286 m3
CT-2 processing internal TT: 1.108 m3
Centrifuge case: 1.318 m3
OmniSync CET processing: 0 m3
*Centrifuge case waste volume is relatively high, due to fine
waste is not stored in the void space of the sand.
Migrating offsets can add to opex cost by $10.00 to $15.00
cubic metres per cubic metre of Ore
OmniSync CET processing:
No Migrating offsets
Immediate solidification
Immediate Water recovery