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R. M. Jadhav and J. S. Sangwai
frequency of deformation for oils of different API gravity (ranging from light to
heavy) obtained from different oilfields in Russia (Ilyin and Strelets 2018). It is
evident that oils of different API gravities behave differently in the presence of
different degrees of deformation (Fig. 5). Oil 1 with the lowest API gravity exhibits
a narrow band between the loss and storage modulus. This indicates that heavy oils
usually have a dominant solid behaviour at ambient temperatures hence the difficulty
in mobilizing them. The deformation rates generate small cracks in the semi-solid
structure of heavy oil. The oil matrix resists the changes in these deformations by
rebounding back to the original structure, which brings forth the elastic nature. This
corresponds to the solid behaviour of heavy oil. As the frequency and amplitude of
shear changes, these small cracks can propagate into larger ones and initiate the flow
of oil which points to the viscous behaviour of oil. These properties are of importance
in understanding how the flow of these oils work and what can be done to improve
it. This is relevant from transportation to processing of these oils. Their interaction
with various chemicals and thermal treatments becomes the basis for understanding
the recovery of these oils.
The processes to recover heavy oils are, however, sometimes too energy exhaustive and complex. Heavy oil recovery takes twice if not more time than the extraction
of light crudes, which puts in perspective the difficulty of the entire process. The
real challenge lies in the optimization of recovery processes. Since most of these
methods utilise steam, the steam-to-oil ratio (SOR) determines the economic value
of the said process. The SOR ratio shift can cause capital costs and requirements of
the process to increase drastically making the process less feasible. Another aspect
of using steam apart from providing heat to reduce viscosity is, it brings chemical
changes in oil composition. Steam causes bond breakage and hydrolysis in oil structure (Clark and Hyne 1984). Usually, the first bond to break is sulphur–carbon as its
dissociation energy is the lowest. The breaking of the sulphur bond helps in achieving low viscosity. This process is termed as aquathermolysis. Aquathermolysis is
one of the main mechanisms in the upgrading of heavy oil. Methods to catalyze the
aquathermolysis reactions draw attention towards nanoparticles and their abilities as
catalysts.
3 Nanomaterials and Their Properties
Nanomaterials are classified as structures at the nanoscale level. They come in various shapes with different arrangements and properties. At such a small scale, their
properties become rather profound. Small structural changes drastically affect the
nature of the particles. The arrangement of the structures can be of various forms such
as nanotubes, crystals, wires, rods and dendrites. They can also be identified based on
their dimensional proportion, 1-dimensional, 2-dimensional, etc. A 1-dimensional
particle will only have one of its sides in the nanoscale (i.e. a nanorod would only
have its radius in nanoscale, and its length could be greater) as such goes for 2- and 3dimensional particles (Tiwari et al. 2012). Figure 6 shows various structures (nanorod
R. M. Jadhav and J. S. Sangwai
frequency of deformation for oils of different API gravity (ranging from light to
heavy) obtained from different oilfields in Russia (Ilyin and Strelets 2018). It is
evident that oils of different API gravities behave differently in the presence of
different degrees of deformation (Fig. 5). Oil 1 with the lowest API gravity exhibits
a narrow band between the loss and storage modulus. This indicates that heavy oils
usually have a dominant solid behaviour at ambient temperatures hence the difficulty
in mobilizing them. The deformation rates generate small cracks in the semi-solid
structure of heavy oil. The oil matrix resists the changes in these deformations by
rebounding back to the original structure, which brings forth the elastic nature. This
corresponds to the solid behaviour of heavy oil. As the frequency and amplitude of
shear changes, these small cracks can propagate into larger ones and initiate the flow
of oil which points to the viscous behaviour of oil. These properties are of importance
in understanding how the flow of these oils work and what can be done to improve
it. This is relevant from transportation to processing of these oils. Their interaction
with various chemicals and thermal treatments becomes the basis for understanding
the recovery of these oils.
The processes to recover heavy oils are, however, sometimes too energy exhaustive and complex. Heavy oil recovery takes twice if not more time than the extraction
of light crudes, which puts in perspective the difficulty of the entire process. The
real challenge lies in the optimization of recovery processes. Since most of these
methods utilise steam, the steam-to-oil ratio (SOR) determines the economic value
of the said process. The SOR ratio shift can cause capital costs and requirements of
the process to increase drastically making the process less feasible. Another aspect
of using steam apart from providing heat to reduce viscosity is, it brings chemical
changes in oil composition. Steam causes bond breakage and hydrolysis in oil structure (Clark and Hyne 1984). Usually, the first bond to break is sulphur–carbon as its
dissociation energy is the lowest. The breaking of the sulphur bond helps in achieving low viscosity. This process is termed as aquathermolysis. Aquathermolysis is
one of the main mechanisms in the upgrading of heavy oil. Methods to catalyze the
aquathermolysis reactions draw attention towards nanoparticles and their abilities as
catalysts.
3 Nanomaterials and Their Properties
Nanomaterials are classified as structures at the nanoscale level. They come in various shapes with different arrangements and properties. At such a small scale, their
properties become rather profound. Small structural changes drastically affect the
nature of the particles. The arrangement of the structures can be of various forms such
as nanotubes, crystals, wires, rods and dendrites. They can also be identified based on
their dimensional proportion, 1-dimensional, 2-dimensional, etc. A 1-dimensional
particle will only have one of its sides in the nanoscale (i.e. a nanorod would only
have its radius in nanoscale, and its length could be greater) as such goes for 2- and 3dimensional particles (Tiwari et al. 2012). Figure 6 shows various structures (nanorod