Stephen W. Almond

Factors Affecting Gelling Agent Residue Under Low Temperature Conditions

The effect of breaker concentration, breaker type, break time, crosslinker, and pH of a fluid system on the relative flow reduction caused by a variety of water-based fracturing systems is discussed. Fluids prepared with standard guar and cellulose gelling agents broken at low temperatures in a variety of porous media have been investigated. An entire fracturing fluid system and not just the specific gelling agent are evaluated to determine which fluid should provide the optimum production increase of an oil well from hydraulic fracturing. 16 refs.

Prudhoe Bay Field Study - Return Fluid Analysis

Monitoring ionic content of returned fluids after various acidizing treatments gives insight into actual chemical acid-spending processes that occur downhole. In this study, laboratory tests and field treatments were performed, and the resultant dissolution processes were monitored. Results show that the high siderite concentration (6 to 12%) in the Sadlerochit formation accounts for most ({approximately} 60 to 70%) of the hydrochloric acid spending, as well as {approximately} 10 to 15% of carbonate spending and {approximately} 10 to 15% of clay dissolution during HF acid treatments. The HF spending was primarily on quartz/chert in the laboratory, Field results, however indicate that the secondary clay dissolution process was the primary HF spending reaction.