Shell pressing CO 2 flood initiative in Kansas

Shell CO₂ Co. Ltd. thinks that carbon dioxide flood enhanced oil recovery can be implemented in Kansas by 2000.

Shell made the prediction at a recent meeting of Kansas oil and gas producers following the Kansas Independent Oil & Gas Association annual conference.

Potential

"There are three producing formations in the Southwest Kansas and Central Kansas Uplift regions where we believe CO₂ flooding could recover 100-400 million bbl of incremental oil," said Lanny Schoeling, Shell's Kansas project leader.

Shell plans to introduce CO₂ into the Morrow formation in southwestern Kansas as soon as possible: "We hope to extend the (CO₂) transportation system into Kansas and begin CO₂ flooding in the Morrow during the next several years," said Schoeling.

The Central Kansas area will take longer, because there have been no CO₂ floods there, and a demonstration is needed: "We've begun screening candidate fields that include both Arbuckle and Lansing-Kansas City formations," Schoeling said. "We will design a demonstration program next year and hope to start injecting CO₂ in about 2000."

Criteria

Shell officials met with about 50 independent operators whom it says are responsible for nearly 60% of Kansas oil output and provided them field candidate evaluation criteria.

"To date, we've hired three Kansas consultants to assist with funding proposals and evaluations, and we've identified the major fields that meet our screening criteria, possible implementation problems, and pilot sites," said Schoeling. "These consultants live in Kansas and have extensive experience in the Central Uplift formations."

Shell says suitable CO₂ flooding criteria include: a well depth of at least 2,000 ft, oil gravity greater than 25°, and favorable waterflood characteristics. The Kansas formations meeting Shell's initial screening criteria are the Lansing-Kansas City and the Arbuckle in the Central Kansas Uplift and the Morrow in Southwest Kansas.

Schoeling said that the Lansing-Kansas City and Morrow pass miscibility requirements (1,160-1,260 psi), adding, "We also have had relatively high waterflood efficiency in the Lansing-Kansas City and CO₂ flooding success in the Morrow in northern Oklahoma."

Shell has made some progress in screening the Arbuckle, where lithology, formation permeability, and the oil's gravity appear prospective. "Our current work involves identifying past well-plugging techniques; obtaining additional oil samples for conclusive miscibility lab measurements; and determining residual oil saturation and original oil in place," Schoeling said. "The Kansas University Energy Research Council (Kuerc) has submitted a funding proposal to Kansas Technology Enterprise Corp. to assist with our initial study of the Central Kansas Uplift. Kuerc also plans to submit to DOE this spring a request to help with pilot project funding in the uplift."

Shell is the corporate sponsor for both funding proposals. Kuerc would contract all related project work through pilot completion late in 2000.