Еnergy efficiency improvement in thermochemical oil treatment processes through optimization of heat exchange media flows

Abstract

Under the conditions of high-viscosity oil production intensification and rising energy costs, optimizing heat flows at well production treatment units is a key factor in reducing operational expenditures. Redirecting scarce water steam for enhanced oil recovery needs requires identifying alternative heat sources for internal technological processes. The paper aims to evaluate technological feasibility and efficiency of complete or partial substitution of water steam with an alternative heat medium, specifically hot oil-containing liquid from an adjacent oilfield, within an inlet heat exchanger block. The study was conducted using computer thermodynamic modeling methods, which served as the basis for developing a digital model of the shell-and-tube heat exchanger block with rigorous tube bundle geometry, while the characterization of high-viscosity emulsions was performed based on actual laboratory data of narrow fraction distillation. The simulation analysis proved that a complete replacement of steam with the oil-containing liquid is impossible due to a deficit in the existing heating surface area. Transitioning to a single-phase medium leads to a 45% decrease in the heat transfer coefficient caused by the high viscosity characteristics of the oil. To address this issue, a combined operation mode of the block was developed and substantiated, providing for the joint utilization of two types of heat exchange media (steam and oil-containing liquid). The proposed scheme ensures stable maintenance of the standard oil treatment temperature at 82°C while simultaneously reducing steam consumption by 21%, which releases significant energy resources for oilfield technological needs and logically justifies the necessity for a deep analysis of such systems.