Use of ultrasound technology to desulfurize and hydrogenate heavy crude oil adds $3.30 to $3.50 in value per barrel of Maya crude according to tests commissioned by the technology developer, SulphCo. SulphCo’s Sonocracking technology upgrades sour heavy crude oils into sweeter, lighter crudes, producing more gallons of usable oil per barrel at lower cost and environmental impact than conventional HDS (Hydro-Desulphurization) units.
SulphCo positions its process as a cost-effective complement to existing refinery HDS units, enabling refiners to avoid or at least reduce the cost of building new, revamping old or operating high-pressure/high-temperature HDS units. In addition, SulphCo’s technology can help to reduce the need for building more hydrogen generation plants.
The SonoCracking technology uses high-power ultrasonic energy on a mixture of crude oil and water in conjunction with inexpensive proprietary catalysts. The use of high-power ultrasound induces cavitations in the processed liquid, creating bubbles which grow, contract and eventually burst under the stress of the ultrasound waves. The bursting generates excess heat and pressure in and around every micrometer and submicrometer-sized bubble.
The entire process takes a few nanoseconds and each bubble behaves as a microreactor accelerating the physical reactions owing to the heat released. The high temperature (10,000 K) and pressure (10,000 psi) conditions cause disruption of molecular bonds.
Free radicals form as a result of the breaking of molecular bonds in the water vapor at the thermolic center of the cavitation bubbles. While a large portion of these free radicals rapidly reform into water vapor, a few bring about the displacement of sulfur in the hydrocarbons. It also results in cracking the bonds of residuum elements, thereby enhancing the crude quality.
The transfer of hydrogen from water to the numerous petroleum streams leads to the removal of sulfur from the crude oil present in these streams. Other than desulfurization, the process also brings about the rupturing of the complex hydrocarbon bonds, resulting in upgrading the value of the hydrocarbon fractions owing to increased product volume and American Petroleum Institute (API) gravity.
SulphoCo commissioned NEXIDEA to analyze the value added in the process using data from recent independent assays of Mexican Maya crude oil before and after treatment with the Sonocracking technology.
Maya crude is Mexico’s main export grade crude and is heavy (22°) and sour (high in sulfur). Accordingly, it sells at a relatively lower price on the world market—$47.06 per barrel last week compared to a global average of $54.36 and Brent at $59.33. Heavy, sour crudes require more processing to meet fuel specifications.
The study explored the economics of replacing normal export blend Maya crude with Sonocracked Maya crude in a typical US Gulf Coast coking refinery. Based on recent pricing (for the 12 months ending September 2006), the study estimated a $3.30 to $3.50 per barrel enhancement to the value of Maya crude oil through the implementation of the Sonocracking( technology.
The evaluation, which utilized a Linear Program model of the typical Gulf Coast coking refinery, considers many variables including pricing, crude oil quality, product specifications, and refinery operating costs. The model assumes a crude slate containing approximately 20% Maya, all of which is replaced with treated Maya in determining the improvement in crude oil value. The improvement is attributed to an increase in the amounts of high-valued products, particularly naphtha and kerosene, present in the treated oil as well as other property improvements which allowed the refinery to optimize its crude and feedstock mix for greatest economic gain.
Due to the specific nature of this analysis, SulphCo plans to undertake a more global economic analysis of the Sonocracking Technology in the future.
SulphCo was awarded The Frost & Sullivan 2006 Excellence in Technology of the Year Award in the field of crude oil refining for the Sonocracking process.