A Novel Application of New High-Strength Plugging Agent in Baikouquan Oilfield

Abstract

The Baikouquan Oilfield is entering middle and later periods of development. Casing failure, caused by the quality of cementing and casing corrosion, affects the normal production of the well. The number of wells in this situation has been increasing in recent years. Some wells with a high aquifer have no way to achieve effective plugging. The conventional measures have short validity periods and low plugging strengths. They cannot meet the requirements of subsequent fracturing operations and long-term production. Therefore, a new type of plugging agent with high strength, temperature resistance, salt resistance and micro-expansion features was designed and developed. The field test was carried out on four wells in the Baikouquan block, including three wells with a strong water-flooded layer and one well with an upper casing leakage point. A field test showed that the leakage formation was successfully plugged under the condition that the oilfield pressure test value was 30 MPa, with a 100% success rate. The average fluid volume decreases by 51.4%, and the average oil volume increases by 270.8%. The average daily oil volume per well increases by 3.2 t/d. The new plugging agent has the characteristics of no regurgitation, fast cementing speed with the new interface, high cementing strength and construction safety. The above advantages are of great significance in reducing the operation cost of oil and water well production and enhancing oil recovery.

Mechanism of Salt Precipitation Blockage in Low-Producing Gas Wells and the Method of Acidification Blockage Removal

“…Based on different wellbore blocking conditions, various blockage removal agents have been employed. For inorganic blockages, options include hydrochloric acid (HCl), 22 mud acid, 23 chelating agents, 24,25 and other blockage removal fluids. dissolve both organic and inorganic scales simultaneously, 26,27 facilitating the one-step removal of various scales.…”