Previous Talks

Wednesday, September 8th, 2010

A Laboratory Study on Wellbore Strengthening

Quan Guo, M-I SWACO

Abstract

Lost circulation or loss of large volumes of drilling fluids to the formation is one of most costly wellbore stability problems.  Much progress has been made in recent years about the ability to “strengthen” a wellbore to reduce the incidence of lost circulation. Wellbore strengthening techniques are now widely applied in the drilling industry.  However, there is considerable controversy on how these strengthening techniques work and on under what conditions they work.

This presentation will present a laboratory study to address the various issues in applying wellbore strengthening through particulate loss prevention materials (LPM).  The fracture aperture, wellbore pressure, fracture closure pressure, pore pressure and fluid loss to the rock matrix are represented in this laboratory setup.  Several hundred tests have been performed to investigate various important issues such as seal or block location, performance of various LPM types and particle size distributions, sizing of LPM with respect to fracture aperture, effect of fluid density. The presentation will also highlight how to select the appropriate strengthening treatment and its application under different conditions.

Speaker Biography

Quan Guo is currently a Manager of Industry Initiatives and a Research Fellow at M-I SWACO, a Schlumberger Company.  Previously, he was with TerraTek from 1992 to 2000, and with Advantek International from 2000 to 2003.  He has a BS degree in Mathematics and Mechanics from Lanzhou University, China; a MS degree in Engineering Mechanics from Huazhong University of Science and Technology, China, and a Ph.D. in Mechanical Engineering from Northwestern University, Illinois, USA.

Wednesday, February 13th, 2008

Increased Assurance in Cuttings Re-Injection – A Geomechanics Perspective

Quan Guo, M-I SWACO

Abstract

Downhole injection of drilling and production wastes involves grinding of the E&P wastes with the presence of water to make an injectable slurry and injecting the conditioned slurry into a deep formation under high pressures to create hydraulic fractures. The technology, often referred as cuttings re-injection (CRI), is very similar to conventional hydraulic fracturing, although the injection duration and volume in CRI are often much larger. CRI has shown success in both onshore and offshore operations and is often the most cost effective and environmentally sound solution for managing drilling and production wastes.

While CRI technology is advancing rapidly bringing with it more critical CRI projects in less favorable environments, it also poses many challenges as these projects are more complicated or critical in environmentally sensitive areas. Historical acceptable performance of CRI in specifically areas of the world, characterized by particular and localized formation and geo-mechanics conditions, have mislead the value of this solution because of adventurous extrapolation of local best practices in a general context. A CRI disposal solution must be supported by a sound engineering assessment, a risk assessment via simulation of different “what if” scenarios that provide operators a window of probabilities. In fact, projects where local best practices were extrapolated and generalized without specific understanding the in-situ geo-mechanics and formation conditions, have lead to project delays and cost overruns. This presentation will present a geomechanics perspective, with case examples, towards risk management and increased assurance of successful CRI projects.

Speaker Biography

Dr. Quan Guo is currently a Global Technical Advisor in Geomechanics with M-I SWACO since 2003. Previously, he was with TerraTek from 1992 to 2000, and with Advantek International from 2000 to 2003. His current primary technical focus is on subsurface issues related to drilling fluids and E&P waste injection. He has a BS degree in Mathematics and Mechanics from Lanzhou University, China; a MS degree in Engineering Mechanics from Huazhong University of Science and Technology, China, and a Ph.D. in Mechanical Engineering from Northwestern University, Illinois, USA.