RESUMEN
It has been proposed that providing energy for cooking and lighting would solve over 65% of energy needs in rural communities. The use of biomass resources has been found not sustainable as other bioproducts such as biodiesel and bioethanol depend on it. More so that there is a depletion of bioresources in some parts of the world. The shift into animal waste such as poultry droppings and cattle dung has huge prospects, but it is not sustainable in the long term as rural farmers depend on it. The use of human excreta is the most available and sustainable due to the human population. This research aims to provide a workable blueprint of biogas production to meet energy needs. The research considers a laboratory-scale experiment whose result is used to project the medium-scale biodigester. Microbial culturing from human waste is used to initiate the codigestion of human excreta and powdered chicken feathers. It is observed that this procedure drastically reduces the high nitrogen content in the biogas and improves its methane and carbon dioxide content. It is observed that the scaled-up biodigester in a worst case scenario can function at 67%. Design parameters are documented for the onward adoption of the technique.
RESUMEN
This research investigates the combined effect of grain size and water salinity on oil recovery. Water flooding experiment was carried out using unconsolidated formation from Niger Delta. Five groups consisting of five samples, were tested for the effective interaction of two factors (grain size and salinity) and how they affect oil recovery. Each group was assigned a particular grain size while the prepared brine concentration was varied within a specified range. The selected grain sizes were obtained from laboratory sieve analyses. For each sand sample, the same concentration of brine used in saturating it was poured into the accumulator and connected to the flooding tube to displace a column of crude oil. The control valve was opened to cause oil displacement. The amount of brine used to displace the crude oil was ten times the pore volume and all the oil in each sample was recovered by the saturated brine solution. Laboratory investigations show that oil recovery was highest for brine concentration of 15,000 ppm; this was also the case in relation to oil recovery and sand grain sizes.
RESUMEN
Investigation of the corrosion degradation behaviour of mild steel in an admixture of coconut shell and egg shell (CS-ES) based nano-fluid was presented in this study. Mild steel coupons were immersed in different concentrations (nine concentrations and the control as a reference) of the developed nano-fluid for a period of 24, 48, 72, 96, 120, 144 and 168 h. Corrosion rate was calculated based on ASTM Standard G1-03 standard practice for preparing, cleaning and evaluation of corrosion test specimens. Open circuit potential measurements (OCP) were also carried out. The potential of the steel samples in the nano-fluid with respect to time was investigated. This dataset could be used in evaluating the performance of mild steel in CS-ES based nano-fluid.
RESUMEN
Naturally occurring radioactive materials (NORMs) and the presence of toxic metals in drilling fluids/their additives have raised research interests in recent times owing to the risks associated with the exposure times for drillers of petroleum wells. In this study, two drilling fluids A and B were formulated, while two other Mud Samples C and D were obtained from drilled shale and shale-sand formation zones. All four fluids were collected and analyzed for the presence of radioactive and heavy metals. Lead (Pb), mercury (Hg), cadmium Cd), zinc (Zn), chromium (Cr), aluminum (Al), arsenic (As), nickel (Ni), and copper (Cu) were detected in the mud samples. The heavy metal contents of the mud samples are in the following decreasing order of magnitude Hg > Pb > Cd > Cr. In Samples A-D, Hg, Pb, Cr, and Cd were found to have significant concentrations, and the concentrations of these metals increased in the mud samples after they were used for drilling. The concentration of Hg was above the permissible limit. Also, the concentrations of Pb, Cu, As, and Al found in Mud Samples A and B can cause skin irritations over long-term exposures, while Cd, Hg, Zn, and Ni present in the samples were within levels that can cause lung infections or immune breakdown when ingested over long periods. The quantities of Cd, Hg, and Cu detected in Mud Samples C and D can cause skin irritations over long-term exposures, while those of As, Zn, Ni, and Al were seen to have the potential to cause dermal infections/diseases. Based on the results obtained, the cancer risk for the drilling crew lies within 1.1 × 10-3 - 7.7 × 10-3 HQ. The highest dose rate, radium release, and external hazard index were obtained for Mud Sample C whose radium equivalent was judged to be far below the critical safe limit for the drillers. The radium equivalent activity for the two field mud samples (C and D) were estimated to be 27.467 and 22.978 Bq kg-1, respectively, which is the maximum activity obtained for the analyzed samples. The maximum radium equivalent activity for Mud Sample C was estimated as 27.48 Bq kg-1 with a corresponding external hazard index of 0.7. Based on the analysis, there is a significant correlation between the concentration of heavy metals and the radionuclides found in the mud samples.
