... Abstract Acidizing is often applied in horizontal wells to improve well performance. Acidizing in horizontal wells differs significantly from the acidizing of vertical wells. The length of acid contact is much longer, the formation properties over the contact length likely vary in a larger...

... of calcite by strong acids, weak acids, and chelating agents, as well as the dissolution of plaster of Paris by water. 7 , 8 These systems are influenced by various transport and reaction processes including the transport of reactants to the mineral surface, reversible surface reactions, and products...

... . The formations were found to be mostly carbonates in nature, specifically dolomite, trending to sandy dolomite. Hydrochloric acid was the natural treating fluid for dissolution of the carbonate portion of the rock to improve conductivity and, therefore, production. Those wells with a higher sand content were...

... and the superposition time function, Δt sup , is defined as Abstract The use of an inverse injectivity versus superposition time plot to diagnose the changing skin factor in a matrix acidizing treatment has been presented previously by Hill and Zhu1. The model has been extended to calculate...

... It is well known that acid sludging problems are greatly enhanced by dissolved iron in acid. 2 - 5 Both ferric (Fe +3 ) and ferrous (Fe +2 ) ions exist in acid solutions during treatment.Ferric ion is particularly damaging, as it has been shown to correlate strongly with the acid sludging...

... ABSTRACT Past production results after acidizing treatments on oil and gas wells have been unsatisfactory in many areas due to the use of conventional acid mixtures along with inadequate lab testing and design procedures. This paper presents a means of acid-oil emulsion and sludge testing...

... — — 197 — 7 " 128 — — 195 — TABLE III POST TREATMENT CUMULATIVE PRODUCTION, (BBLS) FOR INTERLAKE WELLS 1 AND 2 Non-gelled Acid Gelled Acid Well No. 1 year 2 years 1 year 2 years 1 84,767 120,618 149,470 241,864 2 83,512 139,257 118,858 --- Well...

... Abstract Nitrogen and carbon dioxide have proved to be very effective production tools. In many fracturing and acidizing jobs, the use of one of these inert gases along with the stimulation fluid has improved the efficiency of the treatment, and sometimes made the treatment possible. A review...