Exxonmobil Upstream Research Company

Robert Chick Wattenbarger

Robert D Kaminsky

Mori Y Kwan

Hao Huang

Matthew A Dawson

Thomas J Boone

Rahman Khaledi

Owen J Hehmeyer

J Pierre Lebel

Bhargaw L Adibhatla

Jean-Pierre Lebel

Mark S Beckman

Ivan J Kosik

Adam Coutee

Robert Kaminsky

Methods for recovering viscous oil include receiving electrical power from an electrical grid fed by at least one fluctuating electricity supply. The methods also include using at least a portion of the received electrical power to heat a first fluid stream using an electrical heater. The methods also include heating a second fluid stream with a fired-heater using a combustible fuel. The methods further include using both the first and second heated fluid streams to aid oil recovery. In accordance with these methods, the heat output of the electrical heater is adjusted during production operations to at least partially match an estimated mismatch between electrical power supply from and demand on the grid. At the same time, the heat output of the fired-heater is adjusted to at least partially compensate for fluctuations in the electrical heater heat output.

Viscous oil recovery using a fluctuating electric power source and a fired heater

Described are methods of distributing a viscosity reducing solvent to a set of wells terminating in an underground oil reservoir where the variation in the net solvent injection rate is minimized. The net solvent injection rate is the difference between the total solvent injection rate and the total solvent production rate from the set of wells, for example on an instantaneous or daily rate basis. Minimizing this variation can reduce costs associated with surface solvent storage, subsurface solvent storage, and solvent supply, since solvent supply often is least expensive when supplied at near a fixed rate. One option is to operate well pairs and to inject solvent into one well of the pair while producing oil and solvent from the other well of the pair. These methods are particularly useful in solvent-dominated, cyclic or non-cyclic, viscous oil recovery processes.

Method of distributing a viscosity reducing solvent to a set of wells

Described is a way to reduce solvent usage in solvent-dominated oil recovery processes through the use of an emulsion. Injection of an emulsion into an oil reservoir is performed as an alternative or supplement to solvent injection to minimize solvent usage per unit amount of oil recovered. The emulsion may contain solvent and the solvent may form an external-phase of the emulsion. A solvent-external emulsion may be injected and formed using an aqueous liquid or a gas as the internal phase. The emulsion may be an aqueous-external, vapor-internal emulsion with solvent being injected separately or simultaneously. Polymer may be added to viscosify the emulsions and use them for flow diversion in a solvent-dominated process.

Use of a solvent and emulsion for in situ oil recovery

The present invention relates generally to in situ hydrate control during hydrocarbon production when applying a recovery method utilizing cyclic injection of light hydrocarbon solvents. Hydrate formation is limited by creating an energy reserve within a hydrocarbon reservoir adjacent to the wellbore. A heated solvent is injected during an injection phase of a cyclic solvent dominated recovery process to form a heated region adjacent to the wellbore at the end of an injection cycle. The energy reserve is used to act against the evaporative cooling effect caused by subsequent production and associated depressurization to maintain reservoir conditions outside of hydrate formation conditions. In situ conditions are estimated and injected energy amounts are controlled.

Hydrate control in a cyclic solvent-dominated hydrocarbon recovery process

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Houston, TX, United States of America

Robert Chick Wattenbarger