Treatments To Improve the Performance of Injection, Disposal and Water Supply Wells

Abstract

IntroductionService wells are necessary to the efficient recovery of petroleum. If costs are unnecessarily high due to wasted horsepower expended in operating these service wells, the net income from the lease is reduced. For maximum profits, service wells should be maintained at peak operating efficiency, the same as production wells. Many conditions can prevent service wells from Operating at peak efficiency. Evaluation of bottom-hole samples and surface conditions facilitate problem analysis and selection of remedial measures. Acidizing, fracturing, formation clean-up and similar techniques are designed to obtain and preserve maximum permeability in the critical area around the wellbore.ClassificationService wells may be classified as: (1) water injection wells, (2) gas injection wells, (3) brine disposal wells, and (4) water supply wells. Problem identification and elimination can be greatly facilitated by an accurate analysis of well conditions and a subsequent recommendation for proper corrective treatments. Such treatments fall into three categories: (1) initial treatments to permit new wells to operate at maximum capacity, (2) preventive treatments to avoid difficulties inherent in a specific formation or area, and (3) workover treatments to restore maximum operating efficiency to formations which have been damaged. Partial plugging of formation flow channels by various materials is the usual cause of inefficient operations. Such plugging may be due to one or more of the following: 1. Mineral deposits ("gyp") 2. Corrosion products (iron oxide, sulfide) 3. Silicate particles (silt, clay and fine sand) 4. Petroleum residuals (paraffin, asphalt, tar) 5. Organic deposits (bacterial, algeal)