Use of nano-metal particles as catalyst under electromagnetic heating for in-situ heavy oil recovery

Abstract

In order for heavy oil and bitumen recovery to be efficient, all components present within the oil must be produced. To achieve a highly efficient production process it is essential that we are able to produce asphaltenic components and limit their precipitation. Solvent and conventional thermal techniques are largely limited in their ability to crack asphaltenic components; thus, new techniques and catalysts are needed to more efficiently recover heavy oil. When nano-size metal particles are present they catalyze the breaking of carbon–sulfur bonds within asphaltenic components. The result of this process is an increase in saturates and aromatics, while simultaneously reducing the asphaltene content. This process dramatically lowers the viscosity of heavy oil and bitumen by significantly reducing the average molecular weight. This effect can be dramatically increased by having a strong hydrogen donor present and can be completely inhibited by the removal of all hydrogen donors. When conducting these types of reactions in-situ, it is very difficult and expensive to introduce strong hydrogen donors. Therefore, it is imperative that hydrogen donors be created within the oil rather than be introduced from an external source. In this paper, we investigated the effects of microwave radiation, using a 2.45 GHz emitter, on the recovery of heavy oil from a sand pack. Experiments were conducted with and without nano-size nickel catalyst being present. Heavy oil samples were heated at differing power levels until recovery of heavy oil leveled out. In all cases, the nano-nickel catalysts performed better than their microwave-only counterparts due to the increased cracking and vaporization demonstrated by Greff and Babadagli (2011) to take place in the presence of nano-size metal catalysts and microwaves.