TABLE OF CONTENTS Asphaltenic and viscous heavy oils from bituminous deposits are a huge energy reserve to be exploited in next decades. More than 70 countries possess bituminous deposits. In Canada only, the oil reserve considered to be technically recoverable is estimated to be 280 300 Gb (billion of barrels), larger than the Saudi Arabia oil reserves estimated at 240 Gb (Government of Alberta, Canada, 2002).
In general, upgrading concerns to those processes in which the API gravity of the crude oil or its viscosity decrease. Numerous reducing viscosity methods for heavy oil are currently commercialized [407], involving different means, such as physical methods which do not entail any chemical modification of the crude (e.g., de-asphalting) or the actual chemical conversion of the more heavy molecules into lighter compounds.
The physical methods include dilution, emulsification, addition of surface active agents, etc. Chemical conversion includes those methods involving carbon rejection and those of hydrogen addition . So far, there has not been any bioconversion process that has accomplished the developmental stage; however, there have been some MEOR initiatives, which could be taken as inspiration for upgrading routes. Some of them will be mentioned here as examples, but will be specifically identified as MEOR alternatives.
The enormous amount of energetic resource found as asphaltene rich deposits justify the exploration of a bioalternative for upgrading technologies, from which not even enzymatic cracking of asphaltene molecules should not be excluded.
Heavy crude oil is estimated to be present in reservoirs...
