High-temperature production well design and equipment installation, particularly for deep petroleum reservoirs, geothermal wells, and steam injection applications, present a multitude of challenges for operators due to the elevated thermal environments that impart high temperatures to the produced fluid (e.g., steam, oil, gas, etc.). One of the foremost problems is the uncontrolled heat transfer to outer annuli and heat loss from the production tubing. This can be detrimental to the integrity of outer annuli, may reduce the well productivity and could contribute to the formation of gas hydrates. In order to efficiently produce, inject or flow these fluids through production conduits to other facilities, it is necessary to keep them thermally isolated to prevent severe reductions in flow rate and dramatic changes in pressure that lead to tubular failure. To avoid these problems, high-viscosity insulating packer fluids (IPFs) are employed to insulate production tubing from the exterior pipe and to provide the required hydrostatic force. Effective fluids have a low thermal conductivity and also remain viscosified to eliminate convective heat transfer. Until recently, the packer fluid options fell short of meeting these objectives at elevated temperatures [i.e., ≥ 250°F (121°C)] for extended durations.

Through the extensive investigation of multidisciplinary technologies, a superior-performing solids-free aqueous-based IPF was developed for applications in deep high-temperature environments. The novel system covers a broad density range and exhibits heat transfer between 0.12 – 0.16 BTU/hr ft°F. Ultra high-temperature static aging tests have shown superior gel integrity with no thermal thinning after exposure to temperatures in excess of 500°F (260°C). The utilization of nanotechnology and a system of intermolecular associating synthetic macromolecules allow for the formation of the superior gel structure. In addition to the ultra-high thermal stability, the fluids possess thixotropic flow properties, are hydrate inhibitive and are environmentally friendly by Gulf of Mexico (GOM) standards. This paper presents and discusses the laboratory data generated under simulated high-temperature well conditions.

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