Heavy Oils and Residua

Petroleum is by far the most commonly used source of energy, especially as the source of liquid fuels (Table 1.2). Indeed, because of the wide use of petroleum, the past 100 years could very easily be dubbed the

oil century

(Ryan, 1998), the

petroleum era

(compare the

Pleistocene era

), or the

new rock oil age

(compare the

new stone age

). As a result, fossil fuels are projected to be the major sources of energy for the next 50 years. In this respect, petroleum and its associates (heavy oils and residua) are extremely important in any energy scenario, especially those scenarios that relate to the production of liquid fuels.