“When you’re looking at 400° F and 10,000 psi pressure, you just can’t get completion equipment off the shelf,” said TXM Managing Director Gaary Lavold in the operator’s Budapest office. “It takes specialized equipment. Also, the area has few fractures so we have to induce fractures. We also have some H2S problems, so this is a very challenging area in which to operate.”
"Right now, everyone is waiting on TXM to develop their wells. If they are successful, others will definitely follow,” Kramberger said. Hungary’s major operator Magyar Olajipari Vallalat (MOL), which recently celebrated its 70th anniversary as an oil and gas producer, says the potential is well worth the technological challenges that accompany operations in the Mako Trough. “There is a huge potential for unconventional gas there,” Dr. József Dorman, senior fluid technology expert for MOL Plc., said from the company’s Szolnok, Hungary, office. “There’s a big push for unconventional gas below19,680 ft.” Getting to it and getting it out, however,may require the latest in technology, but with some of the tightest environmental regulations in the world, technical developments must be tempered with maintaining the ecological requirements mandated for all members of the European Union (EU). “With all these countries being members of the EU, the environmental regulations are very tight and getting tighter each year. It’s impossible to dump (drilling wastes) anywhere within Central Europe,” said M-I SWACO Operations Manager Michael Brehm.
Those restrictions place distinctive pressure on fluid companies,which normally would recommend oil-based drilling fluids to cope with the extreme heat and pressure of deep gas wells.With invert-emulsion fluids not yet permitted for use in Central Europe, M-I SWACO went back to the drawing board to come up with an environmentally acceptable water-based fluid that would also meet the high performance standards required of drilling deep wells.
“In Hungary, the existence of deep tight gas is well acknowledged and is being targeted by TXM, MOL and Toreador (Hungary Ltd.) and others. Drilling into these tight gas reservoirs means drilling very deep and hot wells with high mud densities.
In addition to these challenges, environmental regulations must be considered, so our technical solutions are somewhat limited,” said Regional Technical Services Manager Pavel Marinescu.
To address those limitations, the local operation conducted extensive lab tests in its technology centers in Stavanger and Houston,which led to the development of an ultra-high temperature water-based fluid system. The as-yet uncommercialized system has proven to be successful.
Completing these wells also means dealing with very high pressures,which require heavy brines or other completion solutions, he added. For the latter, Marinescu specifically mentioned a high temperature version of the company’s widely accepted WARP FLUID TECHNOLOGY, which employs micronized barite as a weighting agent. He said discussions are under way with TXM,which is considering the new technology.
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