Siemens Has Developed a New Water Treatment System Designed to
Handle Wastewater From Shale Drilling
Pittsburgh Post-Gazette
12 August 2011
By Alison Griswold,
Cakes produced daily at Advanced Waste Services in New Castle are not
the edible kind.
The dense, 16-square-foot, slate-like rectangles are made entirely of
sludge, the dry solid residual that results from treating industrial
wastewater. It may sound mundane, but the so-called filter cakes and
the technology that produces them are a "perfect storm" of recycling,
according to facility manager Pat Russell.
And that perfect storm is part of a wave of technology that has surged
in response to logistical and environmental challenges created by
Marcellus Shale natural gas drilling, an enterprise that has brought
both business and controversy to Pennsylvania and other states touched
by the boom.
Advanced Waste Services, a division of an environmental services
company headquartered in West Allis, Wis., has been treating industrial
waste and wastewater created by the hydraulic fracturing or "fracking"
process, a drilling technique that creates small fissures in the rock
to free the natural gases contained there, since 2007.
The company's business has grown as fracking has taken off in
Pennsylvania alongside the region's natural gas boom and frenzied
Marcellus Shale drilling of the past three years. In May, the
industrial waste treatment facility began trying out a new system
created by Cranberry-based Siemens Water Technologies, a division of
German corporation Siemens.
The goal is to further streamline the disposal and reuse of waste in
the industry.
"It's all about the preservation of water," said Anthony Cialella, vice
president and tri-state regional manager of Advanced Waste Services.
"Water is our most precious resource, and without it we wouldn't be
here. We're taking the containments out of it and returning it cleaner."
Siemens' new wastewater treatment system aims to streamline the way in
which fracking water is recycled by reducing the net amount of waste to
be disposed of and by making the process more efficient.
Tioga County installed a similar unit last fall, designed to treat
nearly 300,000 gallons of water from Marcellus Shale drilling and other
local operating wells each day. Siemens also hopes to bring the water
treatment units directly to well sites, thereby eliminating costs
associated with transporting water to and from a treatment facility.
"It reduces [drillers'] operating costs both on delivering fresh water
and having to haul away wastewater to another facility," said Kevin
Warheit, product manager for Siemens Water Technologies. "Truck traffic
is also reduced in some of these rural areas."
Unlike its Tioga County counterpart, the Siemens' unit in New Castle is
not currently handling Marcellus Shale waste.
Though Advanced Waste Services used to treat fracking water, it halted
those services this spring after the Pennsylvania Department of
Environmental Protection requested that gas drilling operators stop
delivering shale wastewater to 15 facilities, including the New Castle
Sanitation Authority, where Advanced Waste Services discharges its
treated water. The state also asked that those facilities cease
discharging water that had been diluted or treated for high
concentrations of total dissolved solids.
The request followed up on regulations that Pennsylvania overhauled in
August 2010 under then-DEP secretary John Hanger.
Until last summer, groups had applied for permits to discharge drilling
wastewater without treating it for dissolved solids. Concentrations as
high as 300,000 parts per million would wind up in the state's
waterways, though the safe drinking water standard allows for only 500
parts per million.
Mr. Hanger said today virtually no wastewater is discharged into rivers
and streams without treatment.
That hasn't precluded the New Castle location from putting the new
Siemens' technology to use treating wastewater produced from industrial
waste and some oil and non-Marcellus Shale natural gas wells. The DEP
request would not preclude Advanced Waste Services from contracting
with Marcellus Shale drillers, taking the technology directly to well
sites, where water could be treated for reuse in fracking, Mr. Cialella
said.
It's a long journey from dirty wastewater to clear, treated water and
freshly pressed filter cakes.
The New Castle plant processes upward of 130,000 gallons of water
daily. That liquid is reduced to about 36,000 gallons of sludge, with
the remaining solids from that mixture separated into the chalky cakes.
Water enters the facility in large trucks -- a typical load measures
about 5,000 gallons -- and is scanned by radiation detectors for any
radioactive or hazardous materials. If the liquid passes the
preliminary inspection, most of it heads into loading tanks while a
small sample is sent to the lab to evaluate suspended solid
concentration, pH level and other chemical properties.
After assessing the water sample in the lab, Advanced Waste Services
begins to process the batch using Siemens technology.
The first tank -- called the reaction tank -- chemically treats the
water to separate the mixture into a clear component that sits atop a
thick layer of sludge by adjusting the pH and adding reactants that
cause the undissolved particles to clump together. As the suspended
solids stick together and settle out, the tank periodically pumps out
the accumulated sludge.
Eventually, the remaining liquid -- now a far thicker mixture --
travels to filter presses, which squeeze out nearly all the moisture
and produce the lime-coated filter cakes. Each press has a capacity of
about 10,000 gallons, and solids are compressed into 80 dense cakes.
Those cakes are placed in landfills; the water is tested again and then
discharged to the New Castle Sanitation Authority.
The process recovers about 70 percent of the water initially brought in
for treatment, said Mr. Cialella.
The final product, according to Mr. Warheit, has a high salinity
content, around 40 percent -- by comparison, seawater is about 3
percent salt -- but is otherwise clean enough to drink.
"You could take the water that comes out of our units, run it through
an evaporator and you could make drinking water," Mr. Warheit said. "It
would be purer than what comes out of the tap."
Water usage by the Marcellus Shale drilling industry has become a
controversial subject, in part because of fears over how the process
will impact water supplies nearby. That debate aside, in terms of
actual water used, industry representatives argue that their operations
make up just a fraction of a percent of the state's total.
"We are an incredibly small user of water, relatively speaking," said
Matt Pitzarella, a spokesman for Range Resources, a leading Marcellus
Shale operator headquartered in Fort Worth, Texas. "Recreation, like
common swimming pools, uses way more water than we do."
While issues around fracking will continue to be debated, there seems
to be little doubt that it has fueled innovation in the treatment of
wastewater.
Though Advanced Waste Services has not handled Marcellus Shale
wastewater since early August, the company is among a growing number of
facilities with technology that can treat water at well sites,
something that more drillers are doing. State College-based Rex Energy
treats and recycles wastewater at well sites, as does Range Resources.
A number of energy and technology companies are offering services
similar to the water treatment done by Siemens' technology.
Aquatech, a Canonsburg-based company that develops water purification
technology, is marketing a mobile wastewater treatment unit that
distills water to eliminate dissolved impurities. The unit is mounted
on a 53-foot trailer, said Devesh Mittal, vice president of industrial
solutions, and will make a technology that has long been used to
desalinate seawater available for fracking and drilling.
Wastewater recycling technology that barely existed in 2008 has become
widespread as Marcellus Shale drilling has increased and environmental
regulations have tightened, said Mr. Hanger, the former DEP chief.
The industry as a whole recycles and reuses about 70 percent of
drilling wastewater today, he added, with some companies preserving
nearly 100 percent.
"This is a huge success story for the environment, it's a huge success
story for the industry, and of course it's a huge success story for the
companies that have developed the technology," Mr. Hanger said.
Alison Griswold: agriswold@post-gazette.com or 412-263-1410.