Commentary - Materials Science and Nanotechnology (2018) Volume 2, Issue 1
Route of advanced material to unlock new energy resources.
Lack of high temperature high pressure (HTHP) elastic seal has been the bottleneck for the energy industry to economically and safely explore geothermal energy and heavy oils, which is extremely abundant but under-developed. Once completely unlocked, it would be one of the main alternative resources to compensate for gradual dearth of easy-to reach traditional oil and gas reservoirs. In exploration of these resources, hot fluids are required to be safely sealed in an enclosed system, the temperature of which could easily reach to 600°F+. However, rubberscurrent material options downhole sealing applications- have found prone to decompose when temperatures approach 600°F and even lower in wet wellbore condition. It is no longer suitable for heavy oil and geothermal wells. On the other hand, metal to metal sealing systems may have the temperature tolerance, but lacks necessary elasticity to provide reliable seal over rough sealing surfaces, the most common working conditions in oil and gas industry. Elastic Carbon Composite (ECC) combines the sealing capacity from expanded graphite (EG) with high mechanical strength of metal material. This novel seal material exhibits excellent thermal/ chemical stability, high mechanical strength and reasonable elasticity, thus fills the seal material gap where rubber does not have enough temperature rating and metal lacks enough elasticity to work reliably. Seal produced made from ECC successfully addressed HTHP seal challenges in heavy oil recovery and geothermal well development. For broader acceptance in other industrial sectors, mechanical properties of this material still needs to be improved to overcome its current disadvantages including anisotropic physical property, low tensile strain, and limited elasticity. Development of this novel composite material not only help oil and gas industry to unlock new energy resource to satisfy steadily increasing global energy-demands, but also provide new insight to advanced material community in how to align academic research with industrial applications.Author(s): Lei Zhao*, Zhiyue Xu, Baker Hughes, A GE Company