The project team of Furness-Newburge, Inc., TechSavants, Inc. and Nicor Gas performed DOE sponsored research from 2000 through 2004 to develop a sonic tool to treat underground natural gas storage wells. One of the primary damage mechanisms for these wells is the formation of scale at the perforations or at the sand face through which the gas flows during gas injection and withdrawal. During well evaluation with backpressure tests (BPT) and multi-rate pressure transient tests (MRPTT), this blockage exhibits itself as a positive skin. The sonic treatment concept is to apply high intensity sound waves to help dissolve and break-up scale that forms at the perforations or the sand face and thereby improve gas/fluid flow.

After initial development of the prototype, the sonic tool was deployed in three separate natural gas storage wells in northern Illinois. The first deployment's purpose was to ensure that the sonic treatment did not damage the well. The second and third field deployments were used to evaluate the sonic treatment's ability to increase productivity as measured by BPT and MRPTT analyses. The second deployment, in a well with a negative skin prior to treatment, showed little or no increase in well productivity. The third deployment, in a well with measured scale damage prior to treatment, showed an increase in well productivity after sonic treatment. Specifically, the skin coefficient dropped from +2.5 to −1.3 and the absolute open flow potential increased 28% from 110 to 141 MMscf/D.

In a separate study, this sonic tool was also deployed in a stripper oil well to see if sonic stimulation could increase oil production. Two treatments six months apart were performed on a well producing 6.2 barrels per day. For oil well deployment, sonic stimulation could improve well production through both viscosity reduction and through opening up blockages in the pores. Well productivity increased 15-30% in the initial period following treatment and then gradually returned to pre-treatment levels after several weeks.

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