Field Pilot to Remove Pyrobitumen Blockage from Oil and Gas Reservoirs with the PRIstine Process

In the spring of 1998, PTAC assisted PRI in the launch of a project for the world’s first field pilot of the new PRI invented PRIstine process to remove pyrobitumen blockage in oil and gas reservoirs. Pyrobitumen is a naturally occurring insoluble material in most of the worlds carbonate reservoirs, which blocks the reservoir permeability. The first pilot of the PRIstine process is scheduled to begin shortly in an oil reservoir in central Alberta. AOSTRA has awarded PRI $140,000 additional funds to support PRIstine field pilot treatments to be started before the end of 1999. The objective is to test the process in a gas well in Alberta in addition to the currently scheduled oil well pilot. PTAC and PRI plan to host an information session shortly to call for proposals from industry for sites for the test.

Pyrobitumen is found in carbonate formations worldwide. In Western Canada carbonates are found in significant quantities up to 6 wt%. Pyrobitumen is a carbon-rich deposit, insoluble in organic solvents, which reduces permeability and occludes reservoir porosity. There is no commercial process to remove pyrobitumen. PRI has laboratory developed and patented the PRIstine ™ process to remove pyrobitumen through the use of a 15 wt% sodium hypochlorite solution containing an additive package. The PRIstine ™ process has been successfully tested on a wide variety of core material from carbonate and sandstone oil and gas reservoirs. PrairieChem Inc. has a license from PRI to supply the proprietary sodium hypochlorite solution. The process is ready to be used in a field pilot to advance the technology development.

The project goal is to organize and finance a consortium to design, conduct and evaluate a field pilot trial to improve productivity by removal of pyrobitumen with the PRIstine™ process. An industry meeting was held on April 2, 1998 to invite companies to participate and nominate reservoirs for the field test. Anderson Exploration and Husky nominated reservoirs. The Alberta Department of Energy encouraged an application for funding which has been submitted in the amount of $140,000. Due to popular request, a second industry meeting was held on April 21, 1998.

Since acid treatments do not remove pyrobitumen, industry members and service company representatives believe the PRIstine™ process may replace acid treatment for this purpose in carbonate wells worldwide.