CHEMICAL COAGULATION OF TAR SAND
PROCESSING WASTEWATER
Paul H. King, Professor
M. Outer Akad, Graduate Research Assistant
Dept. of Civil Engineering and Engineering Mechanics
University of Arizona
Tucson, Arizona 85721
William F. McTernan, Environmental Engineer
Div. of Environmental Sciences
Laramie Energy Technology Center
Laramie, Wyoming 82070
INTRODUCTION
The increasing demand for energy and the concurrent dependence of most major countries on oil
in spite of varying restrictions in supply force consideration of the development of new energy
sources. Tar sands of the Western United States represent one potential new source of energy that is at
present largely untapped. Commercial technology for tar sand development is currently in the exploratory phase. It is evident, however, that effective water quality management will be one key to
ultimate exploitation of tar sands.
Tar sand is a sedimentary rock that contains bitumen or other heavy petroleum. In its natural
state, the energy from tar sands cannot be recovered by conventional petroleum recovery methods.
Recovery is effected by surface mining or, most frequently, by in-situ extraction methods similar to
those schemes which are used for extracting energy from oil shale deposits. The wastewaters under
consideration in this report were generated from in-situ field experiments conducted by the Laramie
Energy Technology Center (LETC) at a site near Vernal, Utah. These represent three of the larger
field scale experiments which have been conducted. At present there is no commercial scale tar sand
extraction industry in the United States. The two initial experiments employed a combustion based
extraction process while the third experiment was designed to evaluate the effectiveness of using steam
to recover in-place bitumen. Table I gives a brief indication of the scope of these field tests as well as
indicating oil production and wastewater recovery data. A full description of the field experiments is
available in the literature [1,2,3].
Wastewaters designated as TS-2C and TS-1S were provided by LETC to the University of Arizona as one phase of an on-going treatability study conducted at several universities and other
research laboratories. Typical water quality data derived from these two extraction methods have
been previously given by McTernan and Marchant [4] and are indicated in Table II. Wastewaters from
the two-phase combustion experiment (TS-2C) exhibit relatively moderate organic loads with typically low concentrations of measureable suspended solids. These waters are highly buffered and are
Table I. Oil and Water Produced During LETC Tar Sand Extraction Experiments
Field Extraction
Experiment   Method
Experiment
Duration
(days)
Oil
Production
(barrels)
Water
Production
(barrels)
Water to
Oil Ratio
TS-IC        Reverse Combustion 25 65 165 2.5
TS-2C Reverse-Forward Combustion 183 580 1700 2.9
TS-1S Steam Drive 180 1150 6250 5.4
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