Integrating Laboratory Analysis for Evaluating and Improving Disposal/Injection Zones Capacity and Determining Well End of Life

Abstract

Consistent performance and reliable long-term injection of fluids into disposal or injection wells is significantly enhanced by designing and implementing a management program tailored to a changing environment. Variations in the quality of produced water over the life of each well results in variation of disposal fluids. These critical changes, often overlooked, can greatly impact the economics and longevity of a disposal or injection well. Planning ahead and following a step-by-step evaluation method will help diffuse a crisis and determine if the well is at the end of life. This method outline in this discussion, provides a concise evaluation plan to determine the need for increasing injection pressures (when allowed) to maintain injection rates for effective disposal or efficient secondary recovery. Client experiences demonstrate injection water quality greatly influences economics and efficiency. Indications of an injection well in trouble (such as increases in injection pressure required for lower injection rates or to maintain production) often lead to higher electric cost, a possible re-frac or even drilling a new well. This discussion outlines a five basic evaluation procedure in detail. It should be noted, a failure at any point in the process should result in an economic review to determine if the injection well is at the fiscal end of life. A cursory geological and reservoir re-evaluation is the least costly and should be the first step taken to see if the well is near end of life. This re-evaluation is closely followed by a detailed water study, in conjunction with an injectability evaluation, surface equipment review and finally a re-frac proposal if indicated. Designing, implementing, and maintaining a consistent management program for disposal and injection wells will ensure injection can be sustained long term, economically and efficiently.

AAPG Datapages/Search and Discovery Article #90332 © 2018 AAPG International Conference and Exhibition, Cape Town, South Africa, November 4-11, 2018