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Kinetic studies of the esterification of free fatty acid (FFA) of rubber seed oil (RSO) for biodiesel production was investigated in this work. Esterification of RSO was carried out in batch experiments using a 1 litre round bottom flask placed on a constant temperature magnetic stirrer. The effect of catalyst concentration (1 – 2.5 vol.%), methanol to oil ratio (1:5 – 1:2 v/v) and temperature (45 – 60o C) on the acid value (AV) of the fatty acid methyl ester (FAME) was investigated. Integral method of kinetic data analysis for constant volume batch reactor systems
was used to study the reaction kinetics with the assumption that the reaction was irreversible. The AV of the FAME was found to decrease as the catalyst concentration was increased. It was also observed that methanol to oil volume ratio of 1:2 gave the least AV as time for esterification reaction was increased. At a temperature of 55o
C, the least AV was recorded after esterification reaction time of 90 min. The kinetics of esterification revealed a second order reaction in FFA with an average rate constant of 0.267 L/mol min. Activation energy and collision frequency factor
were also estimated to be 21.2091 kJ/mol and 671.155 L/mol min respectively.

Numerical simulations of isothermal turbulent gas-solid flow in the riser of a pilot-scale
circulating fluidised bed reactor has been carried out using FLUENT CFD software. An
Eulerian-Eulerian multiphase flow model was used. The constitutive equations in terms of
the granular temperature based on the kinetic theory of granular flow are used to
determine the solids pressure, shear and bulk viscosity. The granular temperature is
determined using both the algebraic and differential transport models. The kε model is
used for the gas phase turbulence. The predicted particle velocity and concentration are
compared with experimental data collected by Huang et al 1 in a riser of 15.1 m in height
and 0.10 m in diameter with particles of 67 μm mean diameter. In general, the measured
trends are well predicted by both the models of granular temperature. However, the
predictions obtained using the differential transport model for the granular temperature
are in a better agreement with data compared with those obtained using the algebraic
model.

This study investigated the effect of retrofitting and systematic upgrade of the Hydro-
cyclone De-oiler unit during produced water treatment. The internal orifice of the oil
reject cones attached to the end of the oil reject Liners was mechanically and
sequentially increased and the performance tested from 1mm up to 2.0mm; and then
dimensioned to a maximum of 3.0mm internal diameter. A single centrifugal pump
(maximum flow-rate of 199m3/hr (30,000 Barrels per Day) and a pressure of 10 -15 barg), was installed along a 6-inch produced water outlet spool of source production separator leading to the De-oiler. This was done in order to boost the operating pressure of the Hydro-cyclone De-Oiler unit to at least, the threshold limit of 5.7 bar-g. Keeping the operating pressure of the De-oiler below 4.2 bar-g, increasing the internal diameter of the oil reject Liner Cone orifice, followed by soaking and cleaning up of the clogged Liner tangential inlet with a 4:1 dilute hydrochloric acid, resulted in an increase in the reject oil production rate from 1.19 barrels per day/orifice to 4.45 barrels per day/orifice (a 374% increase). The introduction of the booster centrifugal pump increased the hydrocyclone operating pressure from an inlet pressure of about 3.5 bar-g to 7.0 bar-g, accelerated the outward acting centrifugal and G-forces to about 10 times its original value and increased the rising velocity of oil droplet size. The Hydro-cyclone De-oiler increased produced water throughput from the critical flow-rate of 77.0 m3
/hr to a maximum capacity of 201 m3 /hr. The main contribution of this research is the fact that produced water treatment unit Hydro-cyclone De-oiler oil reject flow-rate can actually be enhanced to about 177% with about 300% increase in initial oil reject cone orifice internal diameter; as long as the critical pressure drop ratio across the De-oiler or choked flow ratio is below 1.0 bar-g.

First break picking involves detecting the onset arrivals of refracted signals from a single
signal source at the individual receiver in a receiver array. First-break picking can be done
manually or automatically. This work outlines the procedures and benefits of automatic picking
from first arrivals using monitor records obtained from reflection survey in Sufyan Oil Field,
Sudan. The first breaking was done using SeisOptPicker. Reliable picking was ensured by
applying linear move out (LMO) to the data before picking. This was reversed after picking.
The length, in milliseconds, of the time window for the automatic picker to look for the first
arrival on a trace was set to a value of 20-ms to accommodate the large distance between the
nearest and farthest offset. The start time search from last first break pick was set at 0
milliseconds. This means that it will not look for the pick at a time earlier than the current pick.
Traces where the first arrival comes in earlier than the preceding trace were rejected. The
results obtained from the automatic picks were compared with results from conventional
refraction survey. The Sufyan prospect Low Velocity Layer (LVL) consists mainly of three
layers from both refraction survey and parameters computed from first break automatic picks
from production survey. The average thickness of first layer obtained from refraction is 20.0m
as against 22.4m obtained from automatic picks. The velocities calculated for these layers are
435m/s and 400m/s from the refraction and automatic picks respectively. The second layer
thicknesses obtained from the refraction survey and automatic picks from production survey
approaches are 52.8m and 50.0m. Their velocities in the same order are 931m/s and 800m/s.
The consolidated layer average velocity calculated from refraction survey and automatic picks
from production survey are 1850m/s and 1848m/s respectively. The LVL parameters obtained
from automatic first break picks from production survey can be used for static corrections in
the Sufyan oil field without conducting dedicated refraction surveys.

The reservoirs in MGT field, deep offshore Niger Delta Basin Nigeria were studied with the aim of undertaking risk analysis of the identified prospects within the field through geological and volumetric assessments. Petrophysical analysis was carried out using two offset wells comprising gamma ray, resistivity, neutron, density and sonic logs. Seven reservoir sands (A-G) with structural traps, were carefully analyzed through well log and seismic interpretation. Amplitude extraction generated on the reservoir sands showed that only reservoirs: C and E are of goods and quality of possible hydrocarbon prospects. The hydrocarbon volume in place was estimated to be 46.4 and 386 million barrels for Reservoirs B and E respectively. The AVO generated for liquid factor indicated AVO Type III which points out a setting where unconsolidated reservoir sands are encased in higher impedance shales. The results of the study showed that MGT Field has a good hydrocarbon potential however, the geological and volumetric risk analysis of the reservoirs revealed moderately low chance of success of the identified prospect.