Biodegradation of polycyclic aromatic hydrocarbons in crude oil-contaminated soil using composted market waste

Release of crude oil and its products into the environment has resulted in many problems that are of global concern. The objective of this study was to determine effect of Composted Market Waste (CMW) on the degradation of Polycyclic Aromatic Hydrocarbons (PAHs) in crude oil-contaminated soil. Pot experiment was carried out with 1 kg of soil in 7 litres perforated container contaminated with 10 % w/ w crude oil, followed by amendment with CMW at 0, 350 and 450 g. The soil was analysed for PAH after 21 days using GC-FID. Acenaphthylene, Acenaphthene, Phenanthrene, Benzo (g,h,i) perylene, Indeno (1,2,3-cd) perylene, Pyrene and Benzo (b) fluoranthene were present in the crude oil-contaminated soil. Concentrations of PAHs at the end of the experiment were 188.40, 38.45 and 32.73 ppm in control, 350 and 450 g respectively. Composted market waste enhanced degradation of PAHs in crude oil- contaminated soil.Keywords: PAH, Degradation, Crude oil, Compos

Effect of Processing and Storage on the Trace Metal Concentration and Freshness Quality of Catfish (Clarias gariepinus)

The freshness quality of fish is altered by enzymatic and microbial activities, necessitating the application of fish preservation technology. This study assessed trace metals concentration and freshness quality of Catfish (Clarias gariepinus) preserved by oven-drying, brining/oven drying and smoking. The fish were processed to average moisture contents of 15 ± 5 %. Processed fish samples were stored in perforated plastic containers for 11 successive weeks at room temperature and assessed weekly for levels of trace metals (Fe, Zn, Cd, Pb) and physical attributes of odour, flavour and texture. Microbial load was assessed by total viable count (TVC) and biochemical activity by total volatile nitrogen (TVN). The freshness quality of processed fish decreased with increasing storage time and all samples preserved using the three preservation methods contained levels of trace metals below the recommended limits for trace metals in fish and are therefore safe for human consumption. Keywords: Preservation, trace metals, freshness quality, total viable count, total volatile nitroge

Plastic waste as strength modifiers in asphalt for a sustainable environment

This research took the form of an investigation into the applicability of polyethylene terephthalate (PET) as strength modifiers in asphalt road construction. Samples of thoroughly washed, naturally dried and shredded PET wastes were collected. The optimum binder content (OBC) of the unmodified asphalt mix was determined. The bitumen used for the control mix was replaced with PET waste in 1, 3 and 5% proportions. Another sample was prepared with the addition of 1, 3 and 5% of PET waste while the OBC was fixed. The samples were subjected to Marshall Stability (MS) and Marshall Flow (MF) tests. Bulk density (BD), void in total mix (VTM), and void filled with bitumen (VFB) were determined. The results were compared with standards. The PET content obtained that conforms to the specification in AASHTO, ASTM and Nigeria Federal Ministry of Works standards was found to be 1% addition to OBC by weight of aggregate. This percentage PET content was 15% by weight of bitumen with BD, VTM, VFB, MF and MS being 2.38 kg/m3, 3.33%, 82.20%, 4.00 mm and 17.01 kN, respectively. The 1% PET modified asphalt was found to be useful for pavement construction and reduces the quantity of plastic waste in our environment

Optimization study of bioethanol production from sponge gourd ( Luffa cylindrica )

Staff Publicationily available and under-utilized. In this study, SG as a potential source for production of ethanol was studied under statistically optimized conditions. SG was collected, peeled, dried, milled and sieved (1mm). Several pretreatment methods were employed on SG namely: steam explosion, alkaline, combination of alkaline and steam explosion, zinc chlo- ride and sodium sulphite. Central Composite Design (CCD) of Response Surface Methodol- ogy (RSM) was used to design and determine the optimum parameters for glucose yield as well as the fermentation for bioethanol production. The best pretreatment method for sponge gourd was investigated to be sodium sulphite pretreatment with a glucose yield of 6.65 kgm −3 . The sodium sulphite pretreated SG was modelled, optimized and validated with R 2 of 0.9974 at p < 0.05. Glucose production was optimal at conditions: sodium sulphite (9% w/w), temperature (100 °C) and reaction time (60 min) resulting in glucose yield of 6.673 kgm −3 . From the CCD, the factors that gave the highest ethanol concentra- tion of 6.84kgm −3 were inoculum size (7.5 v/v), fermentation time (24 h) and nitrogen source (inorganic). The study concluded that sponge gourd could be a potential feedstock for bioethanol production and would prevent under-utilized agro-waste materials

Qualitative assessment of six-animal dungs in university teaching and research farm

Animal dungs constitute environmental nuisance. This made the daily generated dungs of animals (poultry, rabbit, sheep, goat, pig and cattle) from university teaching and research farms to be comparatively studied for essential elements (N, P, K, Zn and Cu) and heavy metals (Cd and Pb) for their qualities. Animal dungs were sampled four times in 1st, 6th and 12th month interval from May 2018 to May 2019, bucked and analysed for N, P, K, Zn, Cu, Cd and Pb using standardized methods. The data obtained were subjected to descriptive and inferential statistics. Level of N was highest: 1.23 ± 0.17 mg/ kg in poultry dungs in the 12th month. Order of levels of P in all the dungs was observed to be rabbit &gt; cattle &gt; sheep &gt; goat &gt; poultry &gt; pig while order of the determined K was poultry &gt; rabbit &gt; cattle &gt; goat &gt; sheep &gt; pig and were significantly (p &lt; 0.05) different from the 1st to the 12th month. Level of Zn increased in rabbit, sheep and cattle dungs across the months. Levels (mg/ kg) of Cu: 3.27 ± 1.02 and Pb: 0.53 ± 0.26 were highest in pig dungs in the 1st month. Order of presence of the elements was Zn &gt; Cu &gt; Pb &gt; Cd with no possibility of detrimental effects because of their low contents. Elemental contents of the animal dungs differ with potential for sustainable utilization in quality.Keywords: Animal dungs, Essential elements, Heavy metals, Detrimental effects, Nigeri

Quantitative depth estimation using analytic signal at low-latitude for ground gravity survey of Gbede, Oyo State

This paper presents the insitu gravity survey of basement complex rock in Southwestern Nigeria. In the E-W direction, LaCoste and&nbsp; Romberg Gravity Meter type G309 was used to carry out a ground gravity survey where ten traverses were established over a distance of 1000 m by 500 m with station spacing of 20m and a traverse interval of 50 m. Observed gravity values were corrected, analyzed and&nbsp; interpreted quantitatively. The corrected bouguer gravity data were presented as bouguer anomaly graphs. Analytic Signal at low-latitude was adopted to compute the depth to source of iron-ore for a contact, a thin sheet (dyke) and a horizontal cylinder. The result revealed a depth range of 5.45 m-8.25 m for a contact, 9.44 m-14.29 m for a thin sheet (dyke) while a depth range of 12.31 m-18.05 m was estimated for a horizontal cylinder respectively. An average depth of 11.81±3.64 m was estimated for the entire area irrespective of the structural model, this was compared with published magnetic results of the study area and a small disparity of potential field measurements was recorded. The overall computed results signified the existence of iron mineral deposits at low depths across the study area

Assessment of Heavy Metal Pollution of Wetland Soils in Ijokodo, Oyo State, Nigeria

Wetlands soils play significant roles in agricultural food production, but are susceptible to heavy metal contamination from recharge waters and/or agrochemicals. This study investigated distribution and level of pollution of heavy metal in soils of Ijokodo wetland, Oyo state, Southwest Nigeria. Twenty soil samples (top and sub soils) were collected randomly within the wetland in October, 2019 and analyzed for Mn, Fe, Cu, Zn, Pb, Cd, Co, Cr and Ni using standard methods. The degree of heavy metal pollution was assessed by comparing metal concentrations to sediment quality guidelines and soil quality thresholds. The results show that soil within the Ijokodo wetland is moderately polluted with cadmium and nickel at concentrations that could cause adverse impact to the wetland ecosystem. The correlation matrix and PCA both show recharge waters, agricultural inputs and parent rock composition as important sources of metals in the wetland. The presence of heavy metals in wetland soils above permissible limits is of human health concern and calls for continuous monitoring of Ijokodo wetland soils to check heavy metal enrichment above the accepted regulatory limits