A chemical product designed to kill bacteria in hospitals is gaining traction in the oil and gas industry as a solution for treating hydraulic fracturing water. Excelyte, which has been successfully tested on flowback water from the Piceance and Marcellus shale basins, is being tested in eastern Utah’s Uintah Basin for use in hydraulic fracturing, well maintenance and treatment of flowback water, said Integrated Environmental Technologies (IET) CEO David LaVance in an interview with Rigzone.
The water treatment solution is similar to bleach in the sense that chlorine is the active ingredient, but unlike bleach, which is caustic with a high alkaline content, Excelyte is Ph-neutral and benign to humans. However, the product is deadly to aerobic and anaerobic bacteria in water used in hydraulic fracturing.
Excelyte is also effective in killing viruses, and the product has yet been tested on a bacteria it couldn’t kill, including anthrax, said LaVance. Excelyte also is non-toxic and undetectable 90 days after use. Hypochlorous acid, the main active ingredient in Excelyte, has been known for decades as an effective biocide, first being identified as one of the agents used in the body to kill pathogens such as bacteria and viruses in the body.
The chlorine part of the molecule is primarily responsible for the biocidal action, with the remainder of the molecule acting as an oxidizing agent, which has a high affinity for the sulfur in hydrogen sulfide. The sulfur precipitates out of the solution as it oxidizes. IET has devised a method to manufacture the product efficiently and reliably, so it can be used in many applications, ranging from hospital disinfection and food processing to use in oil and gas.
“We did not have the useful product until we determined how to make the product in a Ph-neutral way,” said LaVance. Excelyte is ideal in that it will not impact the effectiveness of hydraulic fracturing fluid or proppants, said LaVance. It also is not corrosive to machinery, and is effective in removing deadly hydrogen sulfide.
The company was established a decade ago to develop Excelyte, originally intended for use in hospitals. The product’s effectiveness in killing bacteria in hospital settings and on fruits and vegetables eventually led to the product’s migration into oil and gas, LaVance explained.
The product now has approval from the U.S. Environmental Protection Agency for use in hospital disinfection, food processing, veterinary practices and oil and gas. Benchmark Performance Group held the license for several years, and did its own testing, along with introducing the product to other companies, primarily for hydraulic fracturing.
Yates Petroleum was one of the original users of the producer for well maintenance. IET is working with about 10 companies in the oil and gas market, either in testing or in use. The impact of hydraulic fracturing on water resources in terms of supply consumption and water quality has led to interest in a water treatment solution effective in killing bacteria without leaving toxic remains over a long period of time.
Control of bacterial growth often is accomplished using biocides such as glutaraldehyde, particularly in multi-stage, high-volume hydraulic fracturing of shale, according to a case study presented at the Society of Petroleum Engineers’ International Symposium on Oilfield Chemistry in 2011.
A study of Excelyte’s use in the Marcellus shale play indicates that it does not persist in flowback water beyond a few days, and that the bacteria count stays at less than 10 cells/mL for up to 81 days after Excelyte’s application to slickwater fluid. The company has successfully deployed Excelyte on the Barnett, Haynesville, and Granite Wash shale regions following its initial deployment in the Marcellus, according to the paper.