41 research outputs found
Examining the Physicochemical and Microbial Qualities and Mineral Content of Selected Brands of Bottled Water Marketed and Consumed in Asaba, Delta State, Nigeria
The quality of bottled water sold in Asaba, Delta State, Nigeria, was investigated in this study. Six (6)
brands of highly consumed bottled water were randomly selected for evaluation of physicochemical parameters, metallic
and nonmetallic inorganic constituents, and microbial properties. The study revealed that physicochemical parameters
such as pH, TDS and Chloride ranged between 6.63±0.03-7.54±0.02, 3.3±0.8-88.4±6.1 and 2.48±0.6-39.3±3.6
respectively, while the metal contents were highly variable amongst the bottled water examined. The study also showed
from bacteriological analysis, that 5.2 % of tested samples had Klebsiella sp., Streptococcus faecalis and Pseudomonas
aeruginosa. Values for the physicochemical and non-metal inorganic elements were below the prescribed maximum limits
of the World Health Organization (WHO) and Standard Organization of Nigeria (SON). Generally, the bottled waters
were found to be microbiologically safe, going by the results of total coliform and heterotrophic plate count and were also
not contaminated by heavy metals. A direct comparison of the values obtained with the mineral water categorization
system showed low mineral content and hence most suitable for low-sodium diets. The study recommends regular
monitoring and analysis of bottled waters sold and consumed in Nigeria for quality assurance
Fertilizer and Sanitary Quality of Digestate Biofertilizer from the Co-digestion of Food Waste and Human Excreta
This research was aimed at assessing the fertilizer quality and public health implications of using
digestate biofertilizer from the anaerobic digestion of food wastes and human excreta. Twelve (12) kg
of food wastes and 3 kg of human excreta were mixed with water in a 1:1 w/v to make 30-l slurry that
was fed into the anaerobic digester to ferment for 60 days at mesophilic temperature (22–31 �C). Though
BOD, COD, organic carbon and ash content in the feedstock were reduced after anaerobic digestion by
50.0%, 10.6%, 74.3% and 1.5% respectively, nitrogen, pH and total solids however increased by 12.1%,
42.5% and 12.4% respectively. The C/N ratios of the feedstock and compost are 135:1 and 15.8:1. The
residual total coliforms of 2.10 � 108 CFU/100 ml in the digestate was above tolerable limits for direct
application on farmlands. Microbial analysis of the digestate biofertilizer revealed the presence of
Pseudomonas, Klebsiella, Clostridium, Bacillus, Bacteroides, Penicillum, Salmollena, and Aspergillus. Klebsiella,
Bacillus, Pseudomonas, Penicillum and Aspergillus can boost the efficiency of the biofertilizer through
nitrogen fixation and nutrient solubility in soils but Klebsiella again and Salmollena are potential health risks
to end users. Further treatment of the digestate for more efficient destruction of pathogens is advise
Drinking Water Quality and Public Health of Selected Towns in SouthWestern Nigeria
database in the study area where none existed previously.
Groundwater samples from bore-holes, hand-pump,
and hand-dug wells of four densely populated towns in South-
WesternNigeria were analyzed in respect to physicochemical
factors, biological factors, and the metals Nickel (Ni), Lead
(Pb), Cadmium (Cd), Zinc (Zn), Copper (Cu), and Iron (Fe)
for six consecutive months from September 2012 to February
2013 to give mean values for each town and water source.
Total aerobic plate, total coliform bacteria, and Escherichia
coli (E. coli)were detected in most of thewater samples from
the different towns and sources considered. Except for total
suspended solids and total solids, the physicochemical parameters
of all the samples were within permissible limits. The
concentrations Pb, Ni, Cr, and Cd were above the minimum
permissible limits. The presence of coliforms and E. coli in
the groundwater samples indicates fecal contamination. The
microorganisms isolated in this study include Enterobacteriaceae,
Staphylococcus aureus, E. coli, Citrobacter, Klebsiella,
Pseudomonas,Bacillus, and Micrococcus species. The
analysis of variance of data obtained from this study shows that bore-hole water samples were safer for drinking that
water samples from hand-pump, and hand dug wells across
the communitie
Assessment of Some Geotechnical Properties of Nigerian Coastal Soil: A Case-Study of Port-Harcourt Beach Mud
Soils naturally exhibit variable engineering properties and thus make the geotechnical
characterization of soil for sustainable design and construction of infrastructure imperative. This study was
undertaken to investigate the geotechnical properties of the underlying soils of the Port-Harcourt Beach Mud, Rivers
State, Nigeria. Five boreholes namely BH1, BH2, BH3, BH4 and BH5 were drilled using hand auger at different
depths of 300mm, 350mm, 400mm, 450mm and 500mm respectively. Basic geotechnical tests were then performed
on the samples in the laboratory to determine their properties. Results obtained showed that the area is underlain
predominantly by poorly graded sands based on the Unified Soil Classification System (USCS). The soil material had
an average Moisture Content of 71%, Liquid Limit of 13%, Plastic Limit of 11%, Plasticity index (PI) of 2% and
Hydraulic Conductivity (K)of 2.88 x 10-1 cm/s. The high values of K show that the aquifer system in the area is
prolific. The soil material however met the requirements of the Nigerian General Specifications for use as subgrade in
the construction of roads
Optimization of biogas from chicken droppings with Cymbopogon citratus
Optimization of biogas production and quality from chicken droppings by anaerobic co-digestion withCymbopogon citratuswas investigated. The anaerobic digestions of chicken droppings, chicken droppingswithC. citratusas well asC. citratusalone were carried out for a period of 30 days at an average ambienttemperature of 33.1�2�C using identical reactors (AeC) respectively. Results obtained indicate thatchicken droppings produced on the average 1.8 L/kg/day of biogas, co-digestion of chicken droppings andC. citratusproduced 1.3 L/kg/day of biogas whileC. citratusalone produced 1.0 L/kg/day with estimatedaverage methane content of 41.71%, 66.20% and 71.95% for reactors AeC respectively. The water boilingrates of biogas from chicken droppings, chicken droppings withC. citratus, andC. citratusalone were0.079 L/min, 0.091 L/min and 0.12 L/min respectively, after the gases were scrubbed with water andslaked lime. It was observed that notwithstanding the higher biogas volumetric yield from chickendroppings digested alone, the co-digestion of chicken droppings withC. citratushad better gas qualitywith respect to the methane content present and cooking rate. This study has shown that the methanecontent of biogas from animal manure substrates could be improved by co-digestion with energy plant
Geotechnical Properties of Clayey Soil Stabilized with Cement-Sawdust Ash for Highway Construction
The study was conducted to investigate the different effects of cement-sawdust ash and cement on a
clayey soil sampled from Mandate Lodge, Landmark University, Omu-Aran, Nigeria. The binder mix of cementsawdust ash (CSDA) was mixed in a ratio of 1:1. The CSDA and cement were added to the soil samples at varying
percentages of 1.5, 3.0, 4.0, and 7.0% by weight of the soil. Atterberg limits and strength tests (unconfined compressive
strength (UCS) and direct shear (DS) test) were performed on the samples to determine the suitability of the stabilized
soil as a construction material in highway pavement.Atterberg limit test result showed that the addition of 7% cement
decreased the liquid limit from 58% to 42% and plasticity index from 18% to 3%, while the addition of 7% CSDA
decreased the liquid limit from 58% to 48% and plasticity index from 18% to 4%. The atterberg limit test results also
showed that the stabilized clayey soil samples met the requirements of the Nigerian General Specifications of maximum
plasticity index (PI) of 30% and liquid limit (LL) of a maximum of 50% when used as a subgrade material in highway
construction. The strength test result showed that the strength values of the samples increased with binder addition and
met with the requirement for use as a subgrade material in highway construction
Geotechnical properties of clayey soil stabilized with cement-sawdust ash for highway construction
The study was conducted to investigate the different effects of cement-sawdust ash and cement on a clayey soil sampled from Mandate Lodge, Landmark University, Omu-Aran, Nigeria. The binder mix of cement sawdust ash (CSDA) was mixed in a ratio of 1:1. The CSDA and cement were added to the soil samples at varying percentages of 1.5, 3.0, 4.0, and 7.0% by weight of the soil. Atterberg limits and strength tests (unconfined compressive strength (UCS) and direct shear (DS) test) were performed on the samples to determine the suitability of the stabilized soil as a construction material in highway pavement. Atterberg limit test result showed that the addition of 7% cement decreased the liquid limit from 58% to 42% and plasticity index from 18% to 3%, while the addition of 7% CSDA decreased the liquid limit from 58% to 48% and plasticity index from 18% to 4%. The Atterberg limit test results also showed that the stabilized clayey soil samples met the requirements of the Nigerian General Specifications of maximum plasticity index (PI) of 30% and liquid limit (LL) of a maximum of 50% when used as a subgrade material in highway construction. The strength test result showed that the strength values of the samples increased with binder addition and met with the requirement for use as a subgrade material in highway construction