Arid Zone Journal of Engineering, Technology and Environment (AZOJETE)
Not a member yet
627 research outputs found
Sort by
Validation of wet chemistry method as alternative to gas chromatography for biogas methane content determination
Get PDFAnaerobic digestion technology has the potential for simultaneous waste treatment and biogas generation. Its rate of dissemination and adoption in most developing countries has however, slowed down for many years partly due to inadequate research facilities such as advanced gas measuring equipment, and associated cost of analyses. This study, therefore, tested and validated the use of classical wet chemistry analysis method (CWCAM) as a readily accessible and cheaper alternative to gas chromatographic method (GCM), for determining the proportion of methane (CH4) in produced biogas. Biogas samples were simultaneously collected every week in 5 ml and 20 ml hypodermic syringes, from a digester in which cassava vinasse (CV) was being codigested with poultry droppings (PD), using ruminal fluids of cattle (RFC) as inoculum. While samples in 5ml syringes were analyzed using the GCM, the 20 ml samples were analyzed using the CWCAM, to determine the percentage of methane in the biogas samples collected each week. The corresponding volumes, corrected to standard temperature and pressure (STP) condition was then calculated. The results from both analytical methods were statistically analyzed and compared using the Data Analysis tool in Microsoft Office Excel. The difference in results from the two methods ranged from -3 to +2.9% with CWCAM giving slightly higher values of methane percentage. Overall, a relatively high coefficient of determination (R2 = 0.9728) and low standard error (SE = 1.4) of the regression equation between the two sets of results indicate that the two methods may be used interchangeably.
 
The Effects of Atmospheric Attenuations on C, Ku and Ka Frequency Bands on Satellite Communication System
Get PDFThis paper presents the effects of atmospheric attenuations on C, Ku and Ka microwave frequency bands. The atmospheric attenuations such as cloud, rain, oxygen and water vapour have a much significant effect on the transmitting and receiving of signals over satellite communication especially in locations prone to rainfall. This paper analyzed the effects of atmospheric attenuation on satellite communications in selected location in the city of Aba. The rainfall, cloud and gas data were measured and collected from the Nigerian meteorological agency for a period of three months using simulink model to determine the frequency bands within the areas affected by bad weather condition. The method employed the use of Matlab and International telecommunication union radiocommunication sector (ITU-R) prediction model which include the fuzzy logic system to improve the received signal on satellite communication. The results obtained shows that for the exceedance time of 0.01, the attenuation values recorded during the rainfall at elevation angles of 100, 200, 300 and 400 are 14.0440, 17.84080, 25.32430, 13.45070, 17.67230, 24.05440, 14.37360, 18.35890, 26.18720, 13.12440, 16.62090, 23.31440, 12.70280, 16.03920 and 22.36270 while for the exceedance time of 1.00, the attenuation values recorded are 0.639130, 0.88553, 1.41930, 0.605330, 0.834540, 1.32490, 0.62090, 0.91320, 1.48480, 0.585040, 0.804960, 1.26970, 0.560440, 0.767250 and 1.2080 respectively. Therefore, the work reported here showed that the effects of satellite connection which suffers from poor signal quality due to atmospheric disturbances in the study area was minimized.
 
Remediation of Crude Oil-Contaminated Soil Using Vermicompost in the Niger Delta Area of Nigeria
Get PDFVermicompost is the product of the decomposition process using various species of worms, to create a mixture of decomposing vegetable or food waste, bedding materials, and vemicast. This process is called vermicomposting, while the rearing of worms for this purpose is called vermiculture. Adsorption of toxic metals has been achieved using Vermicompost, but there is dearth of knowledge in adsorption of crude oil using Vermicompost. This study brings to knowledge the effectiveness of earthworm waste (vermicompost) use for the remediation of crude oil contaminated soils. The remediation methods adopted were batch and column processes conditions. Characterization of the vermicompost and crude oil contaminated soil were performed before and after the soil washing using Fourier transform infrared (FTIR), scanning electron microscopy (SEM), X-ray fluorescence (XRF), X-ray diffraction (XRD) and Atomic adsorption spectrometry (AAS). The optimization of washing parameters, using response surface methodology (RSM) based on Box-Behnken Design was performed on the data from laboratory experiments. Machine learning models [Artificial neural network (ANN), Adaptive Neuro Fuzzy Inference System (ANFIS). ANN and ANFIS were evaluated on the observed and predicted percentage removal of crude-oil using the coefficient of determination (R2) and mean square error (MSE)]. Removal efficiency ranged from 29% to 98.9% for batch process remediation and 56% to 92% for column process remediation. Optimum values of the experimental factors were absorbent dosage of 34.53 g, adsorbate concentration of 69.11 (g/ml), contact time of 25.96 (min), and pH value of 7.71, for batch and column processes. Removal efficiency obtained from the multilevel general factorial design experiment ranged from 56% to 92% for column process remediation and 56% to 92% for column process remediation with the same optimum values of factors. Coefficient of determination (R2) for ANN was (0.9974) and (0.9852) for batch and column process, respectively. This result show strong correlation between the observed and predicted values for batch and column process, respectively, the coefficient of determination (R2) for RSM was (0.9712) and (0.9614), which also demonstrates agreement between observed and predicted values. For the batch and column processes, the ANFIS coefficient of determination was (0.7115) and (0.9978), respectively. Machine learning models appear to be capable of predicting the removal of crude oil from polluted soil using vermicompost
Hydrochemistry of Surface and Groundwater in Parts of Birnin Kebbi Northwestern Nigeria
Get PDFA hydro-chemical investigation of drinking water sources in Birnin Kebbi Old Town and its environs, in northwestern Nigeria, was carried out to determine the potability and suitability of the groundwater for domestic and agricultural uses. Twenty-three water samples were collected from these communities, and their physical and chemical parameters, such as electrical conductivity, total dissolved solids, pH, and temperature, were evaluated. Both the chemical and heavy metal analyses were conducted at the Multi-User Laboratory, Usmanu Danfodiyo University, Sokoto. The results obtained indicated that physical parameters like TDS and EC and chemical parameters like Mg2+, Ca2+ and HCO32- are high, while Cr2+, Fe2+, Ni, and Pb2+ have values that are below the NSDWQ recommended limits. While Na2+, Cu2+, Cl-, and NO3- have values far below the NSDWQ set limit, The Schoeller and Piper diagrams show the dominant water type in the study area to be Ca-Mg-HCO3. However, the Gibbs plot shows the dominant source of the water to be the precipitation domain due to the dissolution of carbonate rocks, while the Wilcox diagram shows that all the water samples in the study area have low salinity. Application of Nemerow’s pollution index method shows that the majority of the sampling locations displayed high NPI values, especially for Ni2+ and Pb2+. The NPI Ni2+ values for eleven (11) out of twenty-three samples, making up 47.83%, have NPI values that range from 7.53 to 90.01, making them unsuitable for drinking purposes. The NPI values for Pb2+ for six (6) samples, making up about 26.09%, have high NPI values that range from 36.37 to 172.56, depicting a high level of pollution
Analysis of Rainfall Trend in Benin and Warri Cities of Southern Nigeria
Get PDFIn this study the trends and patterns in the rainfall of Benin and Warri cities in Southern Nigeria were examined. Rainfall data (1983-2014) for Benin and Warri cities were used. The mean, standard deviation, coefficient of skewness, coefficient of kurtosis, coefficient of variation and standardized anomaly index were used as statistical tools to analyze the data and establish the distribution of rainfall in these cities. SPSS 17 and Minitab 16 were used to analyse the data the data obtained. The result of the trend analysis revealed that the year 2005 recorded the lowest annual rainfall of 229.10mm and 1925.8mm for Benin and Warri respectively. The years 2008 and 2011 recorded the highest rainfall of 4489.8mm and 3068.70mm for Warri and Benin respectively. The mean annual rainfall for the study period was 2162.46mm. The annual rainfall trend indicated a progressive increase in the annual rainfall during the period of study. The implications are that 2011 and 2008 recorded the highest rainfall event, including heavy rainfall, that can lead to flooding for Benin and Warri respectively while 2005 recorded the lowest rainfall events that can lead to drier year, potentially affecting crop yield in both cities. It is recommended that water resources managers should make adequate arrangement on how to prevent flooding by designing and constructing water carrying structures, including adequate urban and regional planning
Evaluating the Effect of Temperature and Prolong Storage on Hibiscus Cannabinus (kenaf) Extracts in Drinking Water Treatment
Get PDFAccess to clean drinking water is a fundamental human right. Yet, improved drinking water is still a major challenge in many developing countries today, retarding progress and human development. This study investigated the coagulation performance of denatured kenaf crude extract (KCE) in water treatment using a jar tester. To assess its coagulation performance, KCE suspension samples were heated at 60, 97 and 140 °C for 2, 4 and 6 h while the remaining samples were stored for 3, 5, 7, 10 and 14 days respectively prior to the test. The results show that maximum turbidity removal of approximately 98, 97 and 99% was achieved with sample heated to 60, 97 and 140 °C from 86% recorded with the unheated sample. Interestingly, KCE which had been stored for 3-day duration achieved maximum turbidity removal of 84% compared with the 88% recorded with the fresh sample, although at a dosage, far lower (40 mg/l) than that of the fresh sample (80 mg/l). Therefore, the use of denatured KCE by heating is advantageous for people in developing countries which resulted in improved turbidity removal performance. Conversely, storing the crude sample did not improve the efficiency but its performance was remarkable at lower dosage.
 
Assessment of Arsenic in Groundwater in Monguno, Borno State, Nigeria
Get PDFArsenic contamination poses a severe health threat in the semi-arid region of North-eastern Nigeria, particularly in Monguno town, Borno State. This study rigorously evaluated groundwater arsenic concentrations in 102 samples from various boreholes across Upper, Middle, and Lower aquifers of the Chad Formation, utilizing the Palintest Digital Arsenator Test Kit. To ensure precision, each water sample underwent analysis twice, totaling 204 tested and analyzed samples. Furthermore, the geographical coordinates of the 102 boreholes were meticulously mapped using QGIS (Quantum Geographic Information System), providing a visual representation and analysis of the arsenic presence. Findings revealed that only 3 samples met the WHO recommended threshold, 56 fell within the 10-50 µg/L range, signifying a low risk, while 43 samples exceeded 50 µg/L, breaching safety limits. Prolonged exposure to high arsenic levels can lead to severe health implications. A comprehensive human health risk assessment considered parameters such as Average Daily Dose (ADD), Hazard Quotient (HQ), and Cancer Risk (CR). Notably, for 43 water sources with arsenic concentrations exceeding 50 µg/L, Hazard Quotient (HQ) values ranged from 1.2 to 5.3, indicating potential health risks. These elevated values underscore potential carcinogenic and non-carcinogenic hazards in Monguno. A direct linear relationship was observed between HQ and arsenic concentrations across all samples, reinforcing the correlation. Despite the absence of specific reference values for Monguno, the analogous trend in North Central Nigeria reinforces this observation. Urgent collaborative efforts are imperative for intervention and remediation, emphasizing the need for cooperation between government agencies, non-governmental organizations, research institutions, and the local community. Continuous research and monitoring are vital to understanding arsenic sources and distribution, ensuring the long-term effectiveness of remediation measures, and securing safe drinking water access for the community
Socio-Economic Characteristics of Residents in Correlation to Groundwater Source in Ikenne Local Government Area, Ogun State, Nigeria
Get PDFThe study examines the residents’ socio-economic characteristics as correlates of groundwater source in Ikenne Local Government Area, Ogun State, Nigeria. The objectives addressed in this study are analysis of the socio-economic characteristics of the residents; sources of groundwater; and relationship between residents’ socio-economic attributes and groundwater source in the study area. A total of two hundred and seventy-two (272) respondents across all the six political wards of Iperu and Ilisan, were administered using questionnaires. Data collected were analysed using frequency distribution, percentage, ANOVA (it is used to establish if there is significance different between variable), Correlation and Regression. The study revealed that there is no significant difference in socioeconomic background of the residents (p > 0.05) except for educational attainment. It was found that correlation exists between groundwater source and marital status, education, income and occupation with exception of gender. Regression results established that 82 % of variability in groundwater source is predicted by residents’ socioeconomic characteristics. It could be concluded that socioeconomic background of the residents significantly influences their source of groundwater. It is therefore imperative that governments at all levels need to come up with policies and programmes that will enhance peoples’ socioeconomic status, thereby enhancing their ability to provide an improved water source
Assessment of Air Quality of Service Stations in a Built-Up Area: A Case Study of Lagos Metropolis
No full textEmissions emanating from commercial facilities in high dense area are subject of concern as more people are being hospitalised or suffering from long term exposure to poor air quality. Thus, there is the need to conduct assessment of air quality and other hazardous emissions in some commercial facilities. This paper presents the air quality index, formaldehyde and environmental emissions emanating from four service stations in Lagos metropolis. Four different filling stations were strategically selected from dense localities and monitored for about 8hrs per day for 30 days. The level of air qualities is assessed respectively for these locations. The data is time-averaged over the period of the data acquisition, and the results are presented. The air quality index for all the service stations were found to be below the recommended threshold by the World Health Organization (WHO) guidelines. The CO, CO2 and HCHO emissions have similar pattern with respect to all locations monitored. Further analyses of emissions from different stations revealed that there is significant difference in service station B (SS B) from service station D (SS D) for CO2 emissions at 95% confidence as Pvalue (0.04) is less than 0.05. A proportion of 51% of CO2 can be accounted for by the emission variability in the service stations. However, there is no significant difference in the other emissions patterns at 95% confidence as Pvalue is greater than 0.05 (Pvalue >0.05) for AQI, CO, HCHO and TVOC emissions. In general, the emissions within the selected built-up areas were found not to sufficiently harm service station workers for short term exposure
Partitioning nutrients cycling in a constructed subsurface wetland treating piggery wastewater for pollution control
Get PDFPiggery wastewater management is an environmental concern due to the risk of nutrient pollution on surface and groundwaters. In surface and subsurface flow constructed wetlands, nutrient removal show inconsistency, and the contributions of their various partitions remain unclear; making the optimization of Constructed Wetlands (CW) systems difficult. Pennisetum clandestinum plants and sediment in constructed wetlands play important roles in nutrient polishing and reduction but their capacities have not been partitioned. An experimental constructed Horizontal Sub-Surface Flow Wetland (HSSFW) planted with Pennisetum clandestinum was fed from a piggery wastewater source at Akwa Ibom State University (AKSU). Samples of piggery wastewater were collected before and after each six respective days of detention in the wetlands. Nutrient mass balances and effluent qualities of the partitions were evaluated based on World Health Organization (WHO) and Nigeria Environmental Standards Regulation Enforcement Agency (NESREA) benchmarks. Nitrogen detention by sediment, plant uptake, denitrification and water column partitions in planted HSSFCW varied between 4.32-18.3, 8.71- 40.3, 6.6-17.4 and 24-80.37% respectively, while the unplanted HSSFCW nitrogen detention varied between 5.3-24.3, 6.3-16, 59.7- 88.4% respectively. Phosphorus detention in planted HSSFCW varied between 7.2-45.2, 3.5-28.6 and 26.2-89.3% for sediment, plant and water column concentrations respectively, while the unplanted HSSFCW phosphorus equilibrium between sediment and water column fluctuated between 9.8-55.6% and 44.4-90.2% respectively. NESREA benchmarks was generally attained in three days. The result outlined the importance of plant uptake and sediment storage as major nutrient removal pathways in wastewater polishing and improving pollution control. Increasing the proficiency of these compartments would also improve removal efficiency and reduce nutrient impact on land and water.