A systematic comparison of various upgrading techniques for heavy oil

Abstract

This study evaluates the economic viability of various post-production upgrading techniques for heavy oil. Heavy oils represent 60% of overall crude oil resources, worldwide. However, there are challenges associated with all phases of operation chain owing to high viscosity and low API. In this study, we present a comparative study of five post-production processing techniques in terms of their recovery factors, and economics.We use five different techniques to study post-production processing of heavy oil: 1) dilution with lighter crude, 2) partial upgrading via visbreaking, and 3) wellsite mini-refinery with three various configurations. Two heavy oil samples are selected based on API gravity and sulfur content. Simulations have been conducted to study various processes for the chosen oil samples. Key parameters controlling each technique have been identified and impact of each parameter have been analyzed with sensitivity studies. Advantages and disadvantages of each process are compared to assess the performance at different operational conditions, including oil price.Results indicate an overall net margin of $1 per barrel for blending, between $7 to $9 per barrel for partial upgrading technique, and between $13 and $20 per barrel for mini-refinery. Moreover, when production rate or the crude price is low, blending yields the best performance as it requires the lowest capital cost. Mini-refinery becomes profitable when production exceeds 20,000 barrel per day or oil price surpasses $ 50 per barrel. In addition, for dilution process operation cost has the largest impact on NPV calculations whereas interest rate and capital cost are most dominant factors for visbreaking and mini-refinery techniques.The main contribution of this work is an economical comparison of different post-production heavy oil processing technologies to identify the optimal process under different conditions.