A Survey of Field Applications of Gel Treatments for Water Shutoff

R.S. Seright and J. Liang – 1994

Abstract

Previously published field results for gel treatments for water shutoff are examined for usable candidate selection guidelines, supplemented by views from seven gel vendors and experts at eight major oil companies. Gel treatments were applied over a remarkably wide range of conditions but with sporadic success — fewer than 45% were successful in two independent surveys. The only candidate selection criterion typically used was producing water/oil ratio. To improve success rates, the source and nature of the water production problem must first be adequately identified. Interwell tracer studies and simple injectivity/productivity calculations are especially useful for diagnosis. Recovery calculations should confirm that considerable mobile oil remains that could be recovered more cost-effectively if a blocking agent can be realistically placed in the correct location.

Improvements are needed in the methods used for sizing gel treatments. The method of sizing should be tailored to the type of channeling problem encountered. Five different types of channeling problems are discussed.

Key Takeaways

  • Fewer than 45% of field gel treatments for water shutoff were successful in two independent surveys — a failure rate driven by inadequate problem diagnosis before treatment selection.
  • The producing water/oil ratio was typically the only criterion used to select candidate wells — an insufficient basis that ignores the source and mechanism of water production and leads to treatment-problem mismatches.
  • Gel treatments were applied over a wide range of conditions without systematic diagnosis — the breadth of application without adequate screening is a primary cause of sporadic results.
  • Interwell tracer studies and simple injectivity/productivity calculations are particularly useful diagnostic tools before gel treatment design — they identify what water cut alone cannot reveal about water production pathways.
  • A recovery calculation confirming meaningful mobile oil remains accessible should be a prerequisite for treatment candidate approval — without this, treatments are often applied where little upside exists.
Read Article

Related Articles