Venezuela’s oil reserves, which played a key role in the recent attack by the United States, are the largest in the world, at around 300 billion barrels. Most of this oil comes from the Orinoco Belt in east-central Venezuela and is heavy or extra-heavy. It is a very dense and viscous oil, similar to bitumen, which is more difficult and expensive to extract and refine than conventional light oil. Yet, despite the disadvantages, the United States has a particular need for this type of crude oil: their refineries were built precisely to process heavy oil, the reserves of which in the world are much more abundant than those of light oil, which are in the process of being depleted.
What characteristics does heavy oil have?
Crude oil is not all the same, but is classified according to its API grade. The higher the API grade, the lower the density of the crude oil: when the API grade is less than 25 it is called heavy oil, when it is greater than 40 it is called light oil. Heavy oil is therefore much denser and more viscous than conventional light oil. Its greater density is due to a composition rich in asphaltenes, resins, sulfur and heavy metals. This, in turn, is the result of degradation processes that occur when the oil migrates towards the surface underground and encounters water containing oxygen and bacteria. This interaction removes the lighter fractions of the hydrocarbons, leaving a heavier mixture similar to bitumen. The largest oil deposits in the world are heavy and extra-heavy oil, like those of Venezuela, and tar sands, like those of Canada.
The critical issues related to the extraction of heavy oil
The high viscosity of heavy oil means that it moves with difficulty, flowing with difficulty into extraction wells, and is therefore much more difficult to recover, although it is found at relatively shallow depths in the Orinoco Belt in Venezuela. More complex extraction techniques are therefore needed, which reduce the viscosity: to this end, thermal methods are used, which use high temperatures, such as the injection of steam at high pressure, and non-thermal methods which consist in the dilution of the heavy oil using solvents capable of fluidizing it. Subsequent refining is also more complex than that of light oil and requires specialized facilities. This results in higher costs, compared to those required by the extraction of light oil, and greater energy and water consumption. Added to these critical issues are the soil disturbances created by extraction methods and the problem of disposing of any contaminants in the crude oil, such as heavy metals.
Why Trump wants Venezuelan oil: the advantages
Despite these disadvantages, it must be considered that heavy oil reserves in the world are much more abundant than those of conventional oil. For this reason, heavy crude oil is destined to play an increasingly significant role in meeting global energy needs. Additionally, heavy oil refineries can produce a wider range of products, including asphalt, lubricating oils and diesel, while light oil is better suited to gasoline and kerosene. To this it must be added that, although expensive to produce and refine, heavy oil can be economically sustainable in the presence of adequate structures and technologies. The United States is largely supplied with the latter: along the coast of the Gulf of Mexico there are in fact many refineries built specifically to process heavy oil. Their creation dates back to the last century, when the import of heavy crude oil from Venezuela was particularly profitable. Investing in heavy oil refineries has allowed the United States to tap into resources much larger than those of light oil, for example, those of heavy oil in Mexico and Colombia.
