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Polycyclic aromatic hydrocarbons (PAHs) are a group of priority pollutants that are persistent, ubiquitous, and toxic, which are released to the environment through natural and anthropogenic sources. The effectiveness of bentonite clay modified with hexadecyl pyridinium bromide has been explored for the removal of five PAHs, fluorene, phenanthrene, anthracene, fluoranthene and benzo[k]fluoranthene from spiked aqueous solutions and synthetic petroleum refinery wastewater. The studies were carried out using batch and fixed-bed column adsorption methods. The effects of various experimental parameters such as pH, mass of sorbent, contact
time and temperature on adsorption were evaluated in a series of batch experiments. The selected working parameters were then used in the fixed-bed column experiment. The removal efficiency of the adsorbent in the batch method ranged from (84 to 97 %) while for the fixedbed column adsorption it ranged from (93 to 99%). Removal of the PAHs from the synthetic petroleum refinery wastewater was higher (91 to 99%) than that from
spiked aqueous solutions (84 to 97 %). The adsorption affinities were related to the hydrophobicity of the PAHs as
determined by their log Know values which were in the order; benzo[k]fluoranthene > fluoranthene > anthracene > phenanthrene > fluorene.

Polycyclic aromatic hydrocarbon (PAHs) is classified as persistent hazardous organic priority
pollutants produced by anthropogenic as well as natural activities. The present study
investigates the kinetics, isotherm, and thermodynamic behavior of five PAHs (fluorene,
phenanthrene, anthracene, fluoranthene and benzo[k]fluoranthene) for their adsorption onto
a Nigerian bentonite clay modified with hexadecylpyridinium bromide. Kinetic models of
pseudo-first order (Lagergren) and pseudo-second order (Ho–McKay) were evaluated for the
kinetic studies and intra-particle diffusion (Weber and Morris) model was applied for the
adsorption mechanism. The results suggest the better applicability of pseudo-second order
model (> 0.99) and the mechanism of the adsorption was found to be intra-particle diffusion
with occurrence of some other mass transfer mechanisms. Among the isotherms, Langmuir,
Freundlich and Temkin models were used for the equilibrium studies, Langmuir isotherm
models exhibited the best fit (> 0.80). The calculated values of RL and n were between 0-1 and
n > 1 respectively, indicating the favorability of the adsorption process. The thermodynamic
parameters: Gibb’s free energy change, ΔG was found to be negative, indicating that the
adsorption process was spontaneous and feasible. The positive values of the enthalpy ΔH and
entropy ΔS changes indicate the endothermic nature of the adsorption process and increase in
the degree of randomness at the solid–liquid interface as well as good affinity of PAHs towards
the adsorbents.

On the basis of the effort by the Delft University of Technology to produce hot water for heating purposes (Delft Geothermal Project, DAP), the Buntsandstein Reservoirs of the Triassic Detfurth and Volpriehausen Formations in the West Netherlands Basin have been identified and delineated for geothermal energy development. The objective was to identify the quality and indicate the distribution of these geothermal energy reservoirs for the purpose of generating electricity. In the light of this, four seismic surveys are interpreted and integrated with well data, which are analysed and interpreted for stratigraphic and structural frameworks, followed by analysis of petrophysical properties. Two porosity/permeability relationships are used for calculating net-to-gross (N/G) at
various permeability cut-offs such as 0.1mD, 1mD, 10mD and 100mD. Net sand ranges from 0.14m to 58.04m for 10mD and 0.1mD permeability cut-offs respectively. Based on different scenarios the average porosity ranges from 6.5% to 16.2% and N/G ranges from 0.6% to 30.8%. Heterogeneity remains an issue of concern, but it is believed that they will generally not serve as a barrier or baffle to flow. The zone in and around Wells MON-03, P18-A-02, P15-01 and P1514 in the central part of the study area show the best reservoir intervals based on average porosity
and N/G values. This zone is therefore recommended as the most plausible for the geothermal energy development project, it is also characterized with depths in the excess of 3,000m and estimated temperatures in excess of 1400C, which are well above the required values for generating electricity.

This study evaluates and analyses the performance of Ibom Power Plant from 2014 to 2016
based on performance indices such as capacity factor, load factor, plant capacity, utilization
factor, overall efficiency, and thermal efficiency. The operating margin which is the emission
factor (CO2 emission factor) that refers to the group of existing power plants whose current
electricity generation would be affected by the proposed clean development mechanism
(CDM) project activity was also determined. Data obtained from the Power Plant inventory
records and fault logbook includes monthly energy generation and number of failures for the
period under study. Results obtained from the analysis showed that the average capacity factor
was 28.89%, the typical load factor as calculated was 88.23%; plant capacity was estimated
to be 1,673,160MWH and the average generating capacity from plant records was
483,333.84MWH. The averages of the overall and thermal efficiencies were 27.37% and
27.92% respectively. Using the CO2 emission factor of 56 KgCO2/GJ, the weighted operating
margin emission factor (EFOM,y1-y3) was determined to be 26.17 KgCO2 /MWH and this was
attributed to increase in economic activities in Akwa Ibom State. Low plant availability as a
result of breakdown or failures, disruption of gas supply and other such factors were identified
among other reasons as key issues responsible for the power plant’s low performance.

Seismic data, Well log data and 3D object generated training image were made available for the study. Visual inspection of the seismic data revealed channel fills in Hatch field Offshore Niger Delta Basin. Two continuous reservoirs named reservoir-D and reservoir-E were penetrated by four and five wells and their lithofacies correlated across the field. The reservoirs in the field were investigated for their lithofacies and channel sand distribution using Multiple Point Geostatistics algorithm of Single Normal Equation Simulation (SNESIM) and Filter-based Simulation (FILTERSIM). The results from the simulations revealed that the training image mean, and
variance is 0.60083 and 0.239835. The mean and variance ensemble histogram for reservoir-D using SNESIM algorithm is 0.598 and 0.240, and that for reservoir-E is 0.599 and 0.240. The mean of means and the mean of the variance ensemble histogram for reservoir-D using FILTERSIM algorithm is 0.681 and 0.217, and that for reservoir-E is 0.683 and 0.216. The results shows that the SNESIM algorithm shows greater similarity to the training image mean and variance than the FILTERSIM algorithm and thus would be preferred in Hatch field.