Water Treatment Key to Natural Gas Drilling
March 1, 2010
Pennsylvania’s prolific Marcellus Shale natural gas basin has given the state an opportunity to create high-paying, green-tech jobs while providing cleaner energy for the nation. However, critical water resource problems have the potential to kill this exciting opportunity unless both water disposal and water re-use challenges can be solved.
The opportunity is in producing clean-burning natural gas – and lots of it. Recent technological innovations in horizontal drilling and hydraulic fracturing have reopened the 54,000-square-mile Marcellus Shale Basin, stretching across Pennsylvania and portions of New York, Ohio and West Virginia. Officials estimate that the Marcellus Shale has the potential to produce nearly 500 trillion cubic feet of gas – enough to supply all of the needs in the United States for nearly two decades. The vision of an era of natural gas, a cleaner energy for the nation, coming from Pennsylvania and surrounding states, is poised to take off in a big way.
But there is a problem. Before this vision can become a reality, acute water disposal and supply restrictions must be solved. The new fracturing technology being deployed to access the Marcellus shale gas 6,000 feet below the surface requires up to 2 million gallons of water per well to be injected into the ground at tremendous pressure. When that water flows back to the surface, it returns with high amounts of total dissolved solids (TDS), or naturally occurring salts that dissolve in frac water, and must be disposed of in an environmentally safe manner. To date, this dirty salty water has been trucked off-site to commercial and municipal sewer treatment plants. These plants are not capable of removing the salts, but merely dilute the dirty water with other wastewaters in order to comply with discharge requirements to the state’s waterways. When the high-TDS water is discharged into Pennsylvania’s watersheds, numerous human and aquatic health concerns arise, including allegations of huge kills of fish, mussels and other aquatic life. Late last year, the state acted, ordering that on January 1, 2011, all water used in the drilling of natural gas wells will be prohibited from being put back into Pennsylvania’s waters, unless it is first treated to remove the salts.
This ruling, in turn, has threatened to halt the state’s natural gas expansion, limiting the creation of tens of thousands of jobs, and keeping cleaner-burning natural gas away from East Coast customers hungry for a cleaner source of energy than either coal or imported oil. Without an economical and sustainable water resource solution, further development of the huge Marcellus Basin is at risk.
“If you’re not removing the salts, you’re not really solving the problem,” says Stan Berdell, president of BLX Inc., a natural gas producer in western Pennsylvania. “Our industry has no choice but to limit our growth if we can’t find a way to clean the salt out of this water so that it can be re-used again and again for our next frac jobs.”
A response has come from a New Mexico company, Altela Inc., which has come up with a solution for BLX’s natural gas wells near Eau Claire, Pa., (coincidentally in keeping with the town name’s meaning: “clear water,” in French). The two companies recently placed into operation a new water purification unit directly at the wellhead that purifies the frac water to remove the salts and other contaminants, so that BLX can use the water again and again for the same frac process. And when they are done with the water, it can go back into the river, in a state said to be purer even than drinking water.
“Recent water restrictions from the Pennsylvania Department of Environ-mental Protection (DEP), both from the freshwater side as well as the wastewater disposal side, will limit the pace of tapping Marcellus natural gas,” says David Kohl, of CWM Environmental Inc., a local environmental company. “Until an economically viable water desalination process proves itself in the field, industry tends to be skeptical. Well, now that problem has been addressed with this Altela unit.”
The new water treatment unit recently started purifying water at the BLX wellhead, and results show a complete success in the purification process. The mobile system is 45 feet long and 8 feet wide – similar in size to a semi-tractor trailer. It continuously is converting the brackish frac water into water that is less than 50 mg/liter in salt concentration – about 10 times cleaner than municipal drinking water.
“This new technology has created a unique opportunity for Pennsylvania’s shale-gas industry to beneficially re-use and expand water supplies. The natural gas industry can now become a key element of environmental sustainability and stewardship here in the northeastern Unites States,” says Berdell.
This new desalination process is designed to economically remove salts and other contaminants with a movable unit that sits directly at the gas wells. The economical factor of the system is centered around its non-pressurized technology, for which it can use inexpensive plastics, rather than corrodible metal, to purify these brackish waters. Its recent success in the Marcellus builds upon the company’s prior installations in the western United States and Canada, including receiving the first-ever water discharge regulatory permit to place clean treated oil-field water directly into the most pristine reach of the Colorado River.
Pennsylvania’s DEP estimates that 16 million gallons per day of freshwater will be used by the shale-gas industry in 2010, and will increase to 19 million gallons per day by 2011. Pennsylvania’s natural gas industry, which is poised to roar back to life and produce thousands of jobs and clean energy for decades to come, now has a powerful water management solution to move forward in an environmentally sustainable manner. Companies now can continue to drill the wells in the massive Marcellus Shale, extract the natural gas, recycle the water, and then put that water into Pennsylvania’s rivers, cleaner than drinking water. Natural gas wells in the Marcellus Shale basin now can be completed in a sustainable manner, providing a clean source of energy to the northeast United States for decades to come, without having to sacrifice the quality of the state’s pristine rivers and waterways.