Distinguished Speaker Andrzej Wojtanowicz
March 15 @ 10:00 am - 11:00 am
Dr. Andrzej Wojtanowicz of LSU Graduate Seminar: Well Integrity Loss due Gas Flow behind Casing – Mechanism, Diagnosis, and Remediation
Abstract: The seminar overviews LSU research program concerning external integrity failure in wells causing gas flow behind the well’s casing – an early-time gas migration dubbed “flow after cementing,” (GFAC), and late-time gas migration known as sustained casing pressure (SCP). Both problems involve hazard of surface air pollution or subsurface gas breaching that might destabilize the well or contaminate groundwater.
Mechanism of GFAC resulting from well hydraulics, time-dependent consistency and filtration of cement slurry is explained with data from laboratory and field experiments. Discussed are GFAC – preventive techniques of cement placement – particularly the method developed at LSU for designing top pulsation of the annular cement after its placement and statistics of the method’s field performance.
Late-time gas migration causing SCP is explained using typical pattern of the regulatory-required casinghead pressure bleed-off and buildup (BB) tets that has been mathematically reproduced at LSU. We employed the resulting software to statistically analyze ffield data from 19 wells affected by sustained casing pressure and we developed quantitative criteria for assing risk of SCP that could replace the existing qualitative approach to regulating SCP.
I will also discuss the LSU research project concerning removal of SCP by surface intervention at wellhead to avoid subsurface operation that involves a workover rig at the well site. The Buoyant Kill technique stops annular gas migration by gravity displacement of the liquid above the cement top with an immiscible heavy (kill) fluid. The project involved a series of tests – from desktop selection of compatible kill fluid to floor-top visualiztion of the kill fluid injection and settling, to pilot-size testing of fluid dispav=cement preformance, to the fullscale demonstration of the process in the pressurized 2750-foot experimental well at LSU.
Bio: Andrew K. Wojtanowicz, Texaco Environmental Chair and Professor in the Craft and Hawkins Petroleum Engineering Department at the Louisiana State University, has also held faculty positions at the AGH University of Science and Technology (AGH UST) in Krakow, Poland (1997-1989), and the New Mexico Institute of Mining and Technology in Socorro, New Mexico (1983-84). More recently, in 2008-2009, Wojtanowicz was a Visiting Distinguished Professor of Petroleum Engineering in The Petroleum Institute in Abu Dhabi, United Arab Emirates, and in the fall of 2019 he worked as Visiting Distinguished Professor for the University of Chongqing in China. A United Nations’ expert in drilling engineering, Wojtanowicz has also worked for the petroleum industry as a drilling engineer, drilling supervisor, and drilling fluids technologist in Europe and Africa. He has MS degree in miningpetroleum engineering, and PhD and DSc degrees in petroleum engineering from AGH UST. He also holds Honorary Professorship in Technical Sciences of the President of Poland. Wojtanowicz studies have been reported in 10 books, 84 journal publications, and 154 conference proceedings. In 1992-93 he worked for Conoco Inc. as an Environmental Research Fellow developing the dewatering technology for closed-loop drilling systems. In 1996, Petroleum Engineer International awarded him a Special Meritorious Award for Engineering Innovation – water coning control technology using wells with Downhole Water Sink (DWS). Since 1997, Wojtanowicz has directed a Joint Industry Project (JIP) concerning R&D and field implementation of DWS. Presently, he also leads an industry-sponsored R&D initiative, Sustained Casing Pressure Program, addressing diagnosis and remediation of well integrity loss due gas migration. Wojtanowicz served as the 2003-04 SPE Distinguished Lecturer of the Downhole Water Separation technology, received the SPE 2003 Health Environment and Safety Award, and the SPE 2008 Distinguished Achievement Award for Petroleum Engineering Faculty. He also received seven different awards for service and contributions to ASME Petroleum Division for his 11-year service as the Editor of ASME Transactions Journal of Energy Resources Technology, from 2000 to 2011, and for organizing and chairing, annually, the Petroleum Technology Symposium of the ASME Ocean Offshore and Arctic Engineering conference (OMAE), since 2012 – present. In 2008, Wojtanowicz is a registered petroleum and environmental engineer in Louisiana.