By: Dennis P. Calvert
Historically, freshwater has been the base fluid
essential for fracking, sweeping, and oil sands recovery because it has been
abundant, readily available, and it has cost very
little. Unfortunately, that is now changing as a longer than
expected global drought is causing the industry to examine new options and
technologies to find new sources of water.
In the pursuit of our
belief at BioLargo, Inc., (BLGO) that ‘everybody deserves affordable clean
water’, we have developed and are introducing the breakthrough AOS Filter™ currently
in commercial pilot testing at the University of Alberta. The invention is expected to impact the entire
water industry because it has
delivered unprecedented results in both decontamination and disinfection.
Prompted by attention-getting results, BioLargo was
invited by the Canadian government and NSERC,
Natural Sciences & Engineering Research Council of Canada, Industrial
Research Chair to help clean very large amounts of toxic produced water from
oil sands recovery operations in Canada. BioLargo cofounded the chair with Suncor,
Syncrude, Shell, Canadian Natural Resources, Total, Epcor, Alberta Innovates,
Alberta Environment and the University of Alberta.
Based on data from decades of observations, NASA scientists have been
predicting the current global drought and warning that it may intensify
throughout the balance of this century and could become the worst drought of
the past 1,000 years. Since 2002, NASA’s GRACE satellites have measured massive groundwater losses
around the globe. Using over 20,000 monitoring wells the USGS has
confirmed groundwater losses all across the
nation and in central California of 5 feet in just one month and 200 feet in
the past few years. The following 11-year chart from NASA demonstrates
declining groundwater globally and includes the central valley of the United
States.
Image by J.T. Reager, NASA Jet Propulsion Laboratory.
The following chart is from the U.S. Drought
Monitor and
demonstrates the severity of the current drought that is sure to impact heavy
fracking operations in California.
If NASA predictions continue to ring true, new
sources to replace freshwater for fracking and oil sands recovery will
certainly be required and new technologies to enable using those new water
sources cost-effectively become essential.
Vikram Rao spent more than 30 years with Halliburton serving
as senior vice president and Chief Technology Officer and is a Senior Technical
Advisor to BioLargo. Dr. Rao points out, “massive amounts of water
used in new wells and in sweeping or flooding secondary recovery operations do
not need to be freshwater. Reused water and underground brackish
water are two obvious sources for replacement. In fact, brackish
water is even preferred over freshwater if its salinity is close to 5,000 parts
per million, (PPM).”
According to Dr. Rao, “for drilling
operations, a little salinity will prevent swelling of clay and since clay is a
component of shale, preventing swelling is useful in the drilling and
fracturing phases of operations. For water flooding, a little
salinity is useful in unlocking oil from the formation. A technical
explanation is that the salinity has to be monovalent, such as from Na
(sodium). In one mechanism, oil is bound to the rock by a divalent
species. The monovalent exchanges ions thus releasing the oil from the
rock.”
Dr. Rao elaborates, “a single well can require as
much as 6 million gallons of water and about one-third of that amount returns
to the surface as flowback water that potentially can be treated and
reused. Before the flowback can be reused, it must be treated to
reduce the high salinity that can range between 15,000 and 250,000 PPM and it
must treated with cost effective disinfection to manage the high levels of
bacteria.”
Brackish groundwater is abundant almost everywhere
and within reasonable depths for harvesting. With typical saline
levels of close to 5,000 PPM it appears to be the best choice for replacing
freshwater. The following USGS map indicates how vast brackish
groundwater is in the United States. Note that the white areas do
not indicate an absence of brackish groundwater but instead indicate that those
areas have not yet been measured and mapped.
As plentiful and available as brackish groundwater
is, it has obvious obstacles of sulphates and subsurface bacteria. According
to Tommy Taylor with Fasken’s Oil & Ranch drillers, the largest private
driller in Texas, "The problem with this particular water is
that it has sulfate in it. If the sulfate combines with barium and
strontium — elements that are found in underground water lying alongside
underground oil and gas formations — the sulfate can ruin your well.”
Ken Code, the Chief
Science Officer of Biolargo, Inc. and Vikram Rao both agree that subsurface bacteria
from backflow and brackish groundwater can pose dangers with ancient species of
bacteria that have evolved and become anaerobic from living at depths without
oxygen for so long that they could turn out to be a major nightmare once
released to the surface where oxygen is plentiful.
A very small number
of drillers are already using brackish groundwater in place of freshwater for
drilling operations and sweeping. Mr. Taylor confirms that the owner
of Faskin’s Oil & Ranch wants to preserve their freshwater aquifer and his
operation is now using membrane technology to desalinate brackish groundwater
from the deeper Santa Rosa Aquifer and chlorine dioxide to disinfect any
potential bacteria. They also have to treat the water for removal of
sulphates.
Chlorine dioxide is
a gas that is highly toxic and can be lethal. In addition to the
apparent dangers, the cost to install the infrastructure to inject this gas
into water must be taken into consideration as well as the cost of maintenance,
operation and the cost of the chlorine itself.
Chlorine dioxide may
be today’s first choice to disinfect brackish groundwater, but the industry
wants a solution that is better and they want it at a lower cost. Other
disinfection technologies such as UV treatment, chemicals or advanced oxidation
systems are available, but they are expensive and, in the end, the most
cost-effective and safest technology will become the new gold standard.
Reverse osmosis is
today’s most cost-effective technology to desalinate the brackish ground water
and the flowback, but the biggest obstacles to using brackish water is still
the high cost of energy requirements for RO treatment, and the cost of
degradation of membranes associated with biofilm management. Hiroko Kasama, lead
consultant for Global Water Intelligence believes biofouling is one of the most
significant challenges in RO desalination because biofilm from bacteria growth
on the filter surfaces causes clogging that greatly increases energy
requirements and it also shortens the filters lives requiring more frequent
replacement of costly membrane filters.
Brackish
groundwater and flowback water are already being used by a handful of drillers
and operators as replacements for freshwater and are living proof that it can
be done. The rising pressure on conserving and managing fresh water
sources will push demand for cost-effective solutions that enable these
replacement strategies to be deployed. New technologies should be
expected to work better than chlorine dioxide and current desalination biofilm
disrupters, and they absolutely must cost less.
Brackish groundwater and backflow
water may be the best and are arguably the only viable options to replace the vanishing
freshwater.
BioLargo has developed the next
generation water treatment technology to address the need for lower cost desalination;
cost effective high-level water disinfection; and, removal of sulphates and a
host of contaminants like aeromatics such as napthenic acids and BTEX commonly
associated with fracking and petroleum derivatives.
BioLargo’s AOS Filter is being showcased
at a symposium this August at the University of Alberta.
