Innovative Stand-Alone Renewable Thermal Energy System for Viscosity Reduction of Heavy Crude Oil
M. Al-Mahmoodi, A. Al-Janabi, S. Al-Obaidani and N. Al-Rawahi
Abstract
Crude oil is a vital component of the global economy, with diverse applications in various sectors. Nowadays, most of the petroleum reserves correspond to heavy and extra-heavy crude oils that have high viscosity and low API gravity. Viscosity strongly influences the flow of heavy crude oil during pipeline transportation in terms of increasing the pressure drop and consequently increasing the pumping power. Overcoming these challenges is crucial for the cost-effective transportation of heavy crude oil while minimizing capital and operational expenses. This study is devoted to developing an eco-friendly sustainable thermal heating system to minimize the viscosity of heavy crude oils by implementing a novel and creative technique involving integrating solar energy with a phase change material (PCM). A heating station prototype was designed to maintain the crude oil within the viscosity operating limit to less than 100cP (API gravity greater than 20◦API). The presented data showed that during the period 8:49:46 AM to 2:34:46 PM, the solar energy was enough to increase oil temperature to 63.21°C or higher, where the viscosity fallen below the critical threshold of 100 cP, signifying the transition to light crude oil characteristics. To achieve system sustainability, the PCM was used during the time span from 5:49:46 PM to 5:49:46 AM. The stored energy in the PCM during daylight was used to maintain the water temperature within the level required to enhance the oil viscosity. However, a challenge emerged during the time spans 5:50-8:48 AM and 2:40-5:50 PM, during which the gained heat by water was not sufficient to increase crude oil temperature to its minimum level of 63oC. To comply with this challenge, 7 Photovoltaic panels of size 330 W/m2 were integrated into the system, to be utilized during the period marked by the encounter with crude oil possessing a viscosity exceeding 100 cP.
