Integrated CO2 Pilot in France: Potential Answer to CO2 Mitigation in Bitumen Production
Authors: Denney Dennis 
Published: February 2015

This article, written by Senior Technology Editor Dennis Denney, contains highlights of paper SPE 117600, "The Integrated CO2 Pilot in the SW of France (Oxy com bustion and Geological Storage): A Potential Answer to CO2 Mitigation in Bitumen Production," by Nicolas Aimard and Claude Prebende, Total, and Denis Cieutat, Ivan Sanchez-Molinero, and Remi Tsiava, Air Liquide, prepared for the 2008 SPE International Thermal Operations and Heavy Oil Symposium, Calgary, 20-23 October. The paper has not been peer reviewed.

Development of extraheavy-oil (EHO) fields in Alberta requires much more processing and energy than for conventional oil. The amount of associated greenhouse-gas emissions could be large, and operators are seeking options to reduce them. Carbon capture and geological storage (CCGS) appears to be the most promising option in addition to power-efficiency increase and use of renewable or alternative energies. Oxycombustion could have advantages over post-combustion for CO2 capture in terms of energy efficiency for steam generation.

Introduction

Oil-sands-production and -processing schemes in Alberta require massive quantities of energy.Steam for use in steam-assisted gravity-drainage (SAGD) projects or for the separation of sand/bitumen extracted from miningElectricity for the water-treatment units, pumping units, separation and treatment units, and other usesHeat for treating and upgrading the produced bitumen (in particular the steam/methane reformer for hydrogen production)

To produce these utilities, natural gas is burned, and thermal equipment (i.e., boilers, gas turbines, and furnaces) will generate large quantities of CO2 in the exhaust. To compare this bitumen production with other oil extraction, the ratio of the quantity of CO2 generated per barrel of produced bitumen (extraction and upgrading) is used. To produce synthetic crude oil, acceptable by conventional refineries, eight times more CO2 would be emitted through production mining (or 12 times more through SAGD) than for the extraction of conventional oil.

The objective is to design facilities with the highest-possible energy efficiency. Beyond that, CO2 capture/storage would reduce CO2 emissions dramatically. The facilities must be "capture ready" (i.e., designed with the ability to integrate CO2-capture equipment). Captured CO2 then would be transported under pressure by pipeline to geological storage sites. In Alberta, potential storage sites are deep saline formations, depleted reservoirs, and enhanced-oil-recovery projects in mature oil fields.

In 2006, Total launched an integrated CCGS project in southwest France, near Lacq. A drum boiler was converted into an oxycombustion unit (i.e., oxygen is used for combustion rather than air to obtain a more-concentrated CO2 stream, thus facilitating its capture). The pilot plant will produce approximately 40 tonnes/h of steam for use in other facilities and will emit up to 120 000 tonnes of CO2 over a 2-year period. The CO2 stream then will be treated, compressed, and conveyed by pipeline to the depleted gas field, Rousse, 30 km away, where it will be injected into a deep carbonate reservoir, as shown in Fig. 1.