Advanced Materials Research Vols. 62-64

Abstract: Energy supply and utilization is one of the economic indices of regional development and standard of living. Energy availability in the rural areas of Nigeria is fast becoming a great challenge with the high cost of cooking gas and kerosene and environmental problems associated with firewood. The paper demonstrated the use of a pilot model study (floating drum plant) of bio-decomposition of animal waste (cattle dung and fodder) in an anaerobic condition (single batch system) to generate methane for domestic cooking. This is a unique way of waste management with additional values of energy accessibility, reliability, quality, cost and benefits including environmental and social aspects. Method involved the pre-treatment of the substrate and its inoculation. Material compositions were batched by weight. Gas produced was monitored for 10 times at 3 days interval effective from the fifth day of retention. Efficiency increased to peak at the 11th day (32.8% of the total cumulative, TC) and reduced to 1.2% TC at the 22nd day.

Abstract: The levels of emissions of gaseous pollutants from indoor fires within the conventional apartment types in Benin City have been studied. In Nigeria indoor smokes from domestic activities and mosquito coils occur in a significant number of houses. This study was conducted using carbon monoxide as a tracer gas within smoke in households over Benin City. Measurements were conducted using the most common residential building-type (flats) in the region. Sampling was done at 0.1m AGL, 1.0m AGL, 2.0m AGL and ceiling height to ascertain vertical distribution. The study indicated that huge levels of CO ranging between 25 and 40 ppm were observed in the self-contained or bachelor’s flat with windows closed during the night for guard against mosquitoes and crawling insects, while similar apartments with windows opened during the night equipped with protective mosquito nets showed CO concentrations with levels of between 28 and 42 ppm. The results of both house-types were significant when compared with values of the World Health Organization (WHO) and Federal ministry of environment (FMENV) acceptable limits for indoor CO concentrations.

Abstract: The thermo-physical properties of some varieties of sawdust and some additives are presented. They are thermal conductivity, heat capacity and specific gravity. The methods of investigation used are Lee’s Disc Apparatus, heat balance and gravimetric method respectively. The sawdust specimens were obtained from six varieties of wood. The additives employed on two typical sawdust samples are cement and silica clay. The values of thermal conductivity range between 0.440 and 0.204 W/m K, and heat capacity between 58,644.08 and 29,584 J/kg K. The highest specific gravity is 0.256 and the least value is 0.107. It was observed that as the clay content increases, specific gravity and the thermal conductivity also increases while the specific heat capacity decreases.

Abstract: Batch treatment of palm oil mill effluent (POME) was investigated using physical, chemical and biological methods. Physiochemical parameters such as pH, sulphate (SO42-), total dissolved solids (TDS), total suspended solid (TSS), chloride ion (Cl-), biological oxygen demand (BOD), chemical oxygen (COD) and metals (Fe2+, Zn2+, Ca2+ and Mg2+) concentrations were determined using American Public Health Association (APHA) methods. The results revealed that significant treatment was achieved at each stage. However, the biological method proved to be the best with percentage reductions of 45.6%, 97.6%, 71,0%, 50.1%, 80.4%, 93.8%, 72.0%, 85.4%, 93.2%, 77.7%, 86.2% and 85.7% for pH, SO42-, TS, TDS, TSS, Cl-, BOD, COD, Fe2+, Zn2+, Ca2+ and Mg2+ respectively. The concentrations after treatment were in conformity with the minimum acceptable standard of FEPA and WHO.

Abstract: Among the multitude of problems existing in the fast urbanizing towns and cities in Nigeria, Solid waste appears to be the most prominent in recent years. Solid waste is seen in huge heaps on any piece of unused land, around buildings and in the open market places. Living with solid waste littered around appears to be an acceptable way of life among the people in most cities in Nigeria in recent years. The work reported in this paper involves a preliminary study of residential solid waste management in the Lagos metropolis in Nigeria. A site-specific study was carried out to estimate the quantity of residential solid waste generation, disposal and management in the metropolis. Structured questionnaires were applied to collect primary information such as size of households, income, Educational level etc. from households. The results obtained indicated that the problem of insufficient available data, insufficient funding, poor understanding of solid waste management by the PSP operators and poor publics attitude are the causes of solid waste crisis in Nigeria. Proposal on strategies for the improvement of the effectiveness of the PSP operators in Lagos metropolis has been presented.

Abstract: The production of an improved sawdust briquette, as an alternate source of fuel has been achieved. In addition to sawdust other constituents of the briquette were silica (sharp sand), starch and kerosene. The density, ash content, calorific values and moisture content of briquette were determined. The composition of starch and kerosene was constant throughout the experiment. It was observed that as silica percentage was increased, there was an increase in the briquette calorific value until maximum value of 20%. The sample which gave the best calorific value was with percentage compositions of 60% sawdust, 20% silica (sharp sand), 5% kerosene and 15% starch with a calorific value of 12.68mJ/kg .The produced briquette had a higher calorific value than wood and other agro waste it was compared with.

Abstract: The feasibility of treating brewery effluent using bio-catalysts (enzymes) was investigated. Carbohydrase, lipase, protease and a mixture enzyme made of carbohydrate and lipase were used. Brewery wastewater samples were collected and analyzed for 96 hrs, at intervals of 12 hrs. The physiochemical properties: biological oxygen demand BOD, chemical oxygen demand COD, total suspended solid (TSS), total dissolved solid TDS, pH, phosphorus (PO4), ammonium nitrogen (NH4-N), total hydrocarbon (THC) were determined using APHA standard method of analysis. The concentrations of the physiochemical properties of the brewery effluent decreased with increasing biodegradation time, for the various enzymes used. However, the different enzymes gave different percentage reductions of each of the physiochemical properties. The order of percentage reduction for the enzyme systems is mixed enzyme > carbohydrase > lipase > protease > control. Hence, the mixed enzyme gave the best results of 90%, 90%, 50%, 100%, 91.6% and 100% reductions for COD, BOD, TSS, NH4-N, PO4 and THC, respectively after 96 hrs. of biotreatment. However, the control gave the least percentage reductions of 6.9%, 5.3%, 16.4%, 7.1%, 5.8% and 50.0% for COD, BOD5, TSS, PO4, NH4-N, and THC respectively.

Abstract: The water cycle is an obvious mode of transmission of enteric diseases. Bacteriologically polluted water is potentially dangerous to health because of possible outbreak of typhoid, dysentery and cholera epidemics. In this paper major sources of drinking water in Ado Ekiti and its environs were examined for physical, chemical and biological qualities. These consists of wells in Adebayo, Ajilosun, Odo-Ado and other suburbs; most popular sachet waters (pure water) produce in Ado- Ekiti and the Pipe-borne water from the state water cooperation (Ureje treatment plants). The results were analyzed using t-distribution method of data analysis and World Health Organization (WHO) Standard was applied. The wells were found to be a little more acidic. All the samples showed high calcium content and some gave total hardness value above WHO standard. 70% of the samples, failed bacteriological test. Samples examined give a wider coverage of drinking water sources in Ado-Ekiti, Ekiti State.

Abstract: The movement of sediment such as sand, silt or gravel by flowing water is of interest to a wide range of engineering disciplines. This study is aimed at developing models, which can be used to predict the magnitude and levels of sediment concentration in Ogbese and Owena Rivers in Ondo State S.W. Nigeria for engineering design purposes. Data were collected from field investigations conducted at the respective sampling stations on the two rivers. The live bed concept used was derived from Liu – Hwang (1954) resistance equations and that of Einstein-Brown (1981) sediment transport concept. The problem was reduced to that of a power law relationship. These data ere fitted into the power relationship to obtain the predicted model of the form: F1Q = k2k1, where the parameters F1Q is the dimensionless sediment discharge,  is the dimensionless bed shear stress, k1 and k2 are sediments transport coefficients. Calibrating the models yielded the values of k1 and k2 for Ogbese river as 0.592 and 0.865 and for Owena river as 0.335 and 1.197 respectively. When tested the predicted models for Ogbese and Owena rivers performed well in comparison with the established models such as Ackers and White (1973), Engleund and Hansen (1967), Yang (1973) a\and Karim (1998). It is concluded that the models developed would be useful for engineering design purposes for Ogbese and Owena rivers.

Abstract: A WaterCAD hydraulic network model of the existing Ikpoba Hill Benin City water distribution system was constructed and calibrated for steady state simulation studies using the network’s physical, operational and calibration data. The model was then used for available fire flow analysis and system improvement design. Our study reveals that the existing network has available fire flow of O l/s and hence cannot provide needed flow for fire suppression. However, the proposed improved network with increased diameters of existing pipes and which also takes into account expected future growth has available fire flow of between 29.6l/s and 40l/s at the nodes in the network.On the basis of available fire flow at the nodes in the system, hydrant tagging, numbering and colour coding which can effectively increase the fire fighting ability of the fire department can be undertaken.