From ‘Vagabonds’ to Ethnobotanical Relevance: Weeds of the Campus Sites of Olabisi Onabanjo University, Ago-Iwoye, Nigeria

A survey of the weed flora of the campus sites of the Olabisi Onabanjo University was undertaken. Several visits were made to the disturbed and undisturbed vegetation of the sites for collection of weeds after which the weeds were prepared in accordance with conventional herbarium practice. A total of seventy-three (73) weed species belonging to twenty-seven (27) families were identified and found to be present within the area of study. The family Poaceae seems to have the highest number of weed species (twelve) available within the area followed by Asteraceae with ten (10) species. Amaranthaceae, Cyperaceae and Euphorbiaceae are also in abundance. These weeds have been discovered to be useful, against the mindset of the uninformed that they are useless or ‘vagabond’ plants. Medicinal uses as well as percentage occurrence of each family are presented. From this study it is obvious that the University sites are not only rich in plant biodiversity but that the plants are also very rich in socio-economic values. It is therefore advisable that these plants should be protected from going into extinction so that all would not be lost due to developmental activities

Modeling of Criteria Air Pollutant Emissions from Selected Nigeria Petroleum Refineries

The dispersion models were used to estimate or predict the concentration of air pollutants or toxins emitted from sources such as industrial plants, vehicular traffic or accidental chemical releases. In this study, the Industrial Source Complex Short Term (ISCST3) emission dispersion model was used to measure the ground level concentration of criteria air pollutants within 50 km radius of location. This model considered emissions from major point sources of pollutants in four existing and twenty-three proposed Nigeria petroleum refineries. The obtained ground level concentration for 24-hr averaging periods of the criteria air pollutants at sensitive receptor around each of the refineries was compared with the National Ambient Air Quality Standards (NAAQS) of Nigeria, World Bank and World Health Organization (WHO) to determine their level of compliance. The highest ground level concentration predicted to be 450 - 1875 μg/m3 for 24-h averaging period was obtained at Tonwei Oil Refinery, Ekeremor Local Government, Bayelsa State, while the lowest ground level concentration predicted to be 0.0099 - 0.1 μg/m3 for 24-h averaging period was obtained at Amakpe International Refinery, Eket Local Government, Akwa Ibom State. Percentage set limits of criteria air pollutants ranging from 0.02% to 94.5% are within the set standard limits and no health risk is associated with areas around the plant’s locations while percentage set limits of criteria pollutants ranging from 1.1 to 55.6 folds of the standards exceed the maximum permitted limits, hence affecting areas around the plants. The air quality standards guiding petroleum refinery emissions must be strictly considered, in order to ensure that the ground level concentrations do not exceed the required standard limits and prevent the adverse effects of air pollution in the Nigeria airshed

Ultimate and Elemental Analysis of Some Common Charcoal in Southwestern Nigeria

Common charcoals from different wood species were collected, identified and prepared for analysis. Ultimate and elemental analyses were carried out. In this study, identified charcoal were characterized. The result showed that in the ultimate analysis, Carbon, Hydrogen and Oxygen are the major content of the charcoal samples and are of great importance for the heating value. Sulphur and Nitrogen content were resent in low in quantity. XRF was used in the elemental analysis and the following elements were detected (Na, Cr, Ni, Cd, Al, K, Mn, P, Ca, Si, Mg, Ti, Fe) In the charcoal samples, the percentages of Si and Al are high while the percentages of (Cd, Fe, Na, Ti, Ni, Mg, P, K, Cr) were low. Percentage of silicon was between 50% to 65% in Albizia zygia, Milicia excelsa, Terminalia avicennioides, Funtumia elastica, Milletia thonningii and Hevea brsiliensis with Hevea brasiliensis having the highest which suggested high slagging propensity. Anogeissus leiocarpa, Afzelia bipindensis, Vitellia paradoxum, and Burkea africana have high Na/K. The ratio of Ca/ Mg is greater than 2 in all the samples. LOI ranges from 54.56 – 7.88% with a mean of 25.978±22.909%

Gaseous Emission from the Combustion of AGO from the KRPC in Nigeria

Refined petroleum products from Kaduna refinery and petroleum company serves as a source of energy to the nation but gaseous emission from the combustion of these refined products can be harmful to the ecosystem. Gaseous emission from the combustion of AGO of different volumes from Kaduna Refinery was characterized for gaseous air pollutants using the E8500 combustion analyzer. The concentrations for the gaseous emission from the combustion of AGO were 45.84 mg/m3 HC, 16.33 mg/m3 CO, 206.33 mg/m3 NOx for 10 mL. 76.39 mg/m3 HC, 44.33 mg/m3 CO, 689.33 mg/m3 NOx for 20 mL 102.59 mg/m3 HC, 0 mg/m3 CO, 692.67 mg/m3 NOx for 30 ml. 154.97 mg/m3 HC, 0 mg/m3 CO, 1459 mg/m3 NOx for 40 ml. 141.88 mg/m3 HC, 0 mg/m3 CO, 1516.33 mg/m3 NOx, for 50 ml. This study shows that CO and HC exceeded the acceptable limit for stationary sources while NOx and SO2 were below the acceptable limit. Hence, there is a need for rapid response and urgent attention from government and regulatory bodies to put in place policies that will help minimize the effect of these emissions

ESTIMATION OF EMISSION FACTOR FROM THE COMBUSTION OF AGO, PMS AND DPK FROM THE KADUNA REFINERY AND PETROLEUM COMPANY IN NIGERIA

Air emissions from the combustion of AGO, PMS and DPK were characterized for gaseous air pollutants using an E8500 combustion gas analyzer. The measured concentrations were used to calculate the emission factors of the pollutants. The emission factors for the gaseous emission from AGO were for 10 ml of AGO, HC was 4.584E-05 g/l, CO was 1.633E-05 g/l, NOx was 0.00021 g/l, and zero values were recorded for both CO2 and SO2; for 50 ml of AGO, HC was 0.000142 g/l, NOx was 0.001516 g/l and zero values were recorded for both CO, CO2 and SO2. From PMS were for 10 ml of PMS, HC was 6.9846E-05 g/l, CO was 0.00017 g/l, NOx was 0.00034 g/l, and zero values were recorded for both CO2 and SO2; for 50 ml of PMS, HC was 8.731E-05 g/l, CO was 0.000213 g/l, NOx was 0.0008 g/l, SO2 was 3.76E-06 g/l and CO2 was 0.0066 g/l. From DPK were for 10 ml of DPK, HC was 3.4923E-05 g/l, CO was 2.1667E-05 g/l, NOx was 0.000089 g/l, and zero values were recorded for both CO2 and SO2; for 50 ml of DPK, HC was 6.1115E-05 g/l, CO was 4.0667E-05 g/l, NOx was 0.000191 g/l and SO2 was 2.667E-06 g/l. This study shows that For 10 ml, DPK had the minimum emission factor for HC, AGO had the minimum emission factor for CO, DPK had the minimum emission factor for NOx. For 50 ml, AGO had the minimum emission factor for CO, SO2, DPK had the minimum emission factor for HC, NOx. Therefore, AGO and DPK can act as a source of fuel with the best sustainable environmental effects

Investigation of Air Emissions from Artisanal Petroleum Refineries in the Niger-Delta Nigeria

The increase in price of the available refined petroleum products for local consumption in Nigeria had led to the emergence of indigenous technology for petroleum refining in some parts of the Niger Delta region. This study, therefore characterized and quantified artisanal refineries’ gaseous emissions for possible air pollutants based on various unit operations involved and evaluated their impacts. It measured the emissions directly from source using E8500 Portable Combustion Analyzer. It also categorized oven sizes/processing capacity of the refineries into various ranges in order to estimate emissions according to processing capacity. The result revealed that; pollutants emission varied significantly between the unit operations and increased with increase in processing capacity. When the emissions were compared with daily limits set by the Environmental Guidelines and Standard for Petroleum Industry in Nigeria (EGASPIN) 2002, the emissions (CO, NOx, and SO2) breached the available set limits. While with the Federal Environmental Protection Agency (FEPA), 1991 set limits for emissions from stationary source; HC and CO breached their limits. SO2 and H2S breached their lower limits but were below the upper limit, while NOx emissions were found within its set limit. The study concluded that, Nigeria Artisanal Petroleum Refineries are sources of air pollution, as they impact the host environment

Experimental Investigation of the Electrical Resistivity of Cement Dust

Electrical resistivity is one of the important particle–based factors influencing the performance of an Electrostatic Precipitator (ESP), a particulate control device commonly employed in most cement industries in Nigeria. Therefore, this study investigated the electrical resistivity of Cement Kiln Dust (CKD) across nine locally-operated cement manufacturing plants in Nigeria with the aim of tracing causes of performance problems associated with the ESP used for dust control in the plants. Samples of CKD were collected from the ESPs of these plants and tested for their resistance using the two probe method. The measured electrical resistivities were in the range of 108 – 1011 Ω·cm and showed strong dependence on temperature and slight variation with particle size. The CKD’s resistivity increases as temperature rises from ambient to about 250℃ and declines as temperature rises above 300℃; Nevertheless, the resistivities are adaptable for efficient ESP performance in the collection of cement dust

Factors Influencing Innovation and Competitiveness in the Service Sector in Nigeria: a Sub-Sectoral Approach

Abstract This study examined the factors that influence innovation and competiveness in the indigenous Nigeria's oil and gas servicing firms. Th is was done with a view to making appropriate strategic recommendations to enhance firm-level innovativeness so as to increase indigenous participation in the sub-sector. The study, wh ich used primary and secondary data sources, was based on a sample of the indigenous oil and gas servicing firms in Nigeria. Four types of questionnaire were ad ministered in each firm. A total of 400 questionnaires were administered on heads of Production, Engineering, Finance and Administration in the firms out of which 70% were returned and found suitable for analysis. This was supplemented with field observations and interviews. Secondary data were sourced fro m the internet and other published sources. The data so obtained were analysed using descriptive and inferential statistics. The technological factors that accounted for the innovation performance included the educational qualifications, training and prior work experience of the heads of technical department, nu mber of r&d staff and training, innovation, and, r&d investment. The important non-technological factors included interaction with co mpetitors, consumers, suppliers and training institution. In conclusion, our study found out that the most important factors that influence innovation in the sub-sector are r&d expenditure and training. Keywords R&d Expenditure, R&d Staff, Train ing, Educational Level, Innovation Background The Nigerian economy since the last four decades has become reliant on the oil and gas sector, which accounts for more than 90 percent of export revenues and 41 percent of her Gross Domestic product (GDP

Proximate analysis of some common charcoal in Southwestern Nigeria

analyses were carried out. The study aimed to characterize the identified charcoal and suggest the best charcoal that will give the minimal pollution effect. The result showed that the moisture content of the charcoal ranges between 3.26 and 8.40 wt% with an arithmetic mean of 5.36 ±1.50 wt%, the volatile content ranges between 3.05 and 13.62 wt% with an arithmetic mean of 7.20 ±3.55 wt%, the fixed carbon ranges between 76.83 and 90.57 wt% with an arithmetic mean of 83.54 ±4.60 wt%, and the ash content ranges between 3.09 and 5.18 wt% with an arithmetic mean of 3.87 ±0.70 wt%. The heating value of charcoal of different wood species were determined using Bomb calorimeter. Afzelia bipindensis has the highest ash content while Hevea brasiliensis has the lowest ash content. The heating value ranges 31.82–39.42 kJ/kg with a mean of 35.375 ±2.673 kJ/kg. This shows that Burkea africana could be best for use as a cooking fuel for households and restaurants because it has the best fuel property in terms of moisture content

The effect of air-fuel ratio on tailpipe exhaust emission of motorcycles

This article presents the actual AFR of the vehicular emission from the tailpipe data of motorcycles with petrol engine in Southwest Nigeria. It also presents the ratio between the actual air-fuel ratio (AFRactual) and the ideal/ stoichiometric air-fuel ratio (AFRideal) known as the equivalence air-fuel ratio or lambda (λ). This was compared with the expected value for lambda by the catalytic technology for exhaust gases emission, which is 1 (± 5%). In this study, over 95% of the sampled motorcycles have higher lambda values than expected, thereby emitting very high concentrations of carbon monoxide (CO), hydrocarbon (HC), and carbon dioxide (CO2). The Portable, Hand- Held, battery-operated Kane automotive 4-gas analyser with detector tube (Model Auto 4-1) was used to measure the automobile emissions. The air-fuel ratio is a significant indicator and very important measure for gasoline engine performance controlling and tuning, and anti vehicles exhaust emissions pollution reasons [1]. Internal combustion (IC) gasoline fuelled engines exhaust gases emission depend heavily and mainly on the air-fuel ratio. For a gasoline fuelled engine, carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) exhaust gases emission are significantly influenced by air-fuel ratio. CO and HC are majorly generated or produced with rich air–fuel mixture, while NOx with lean air-fuel mixtures which mean that there is no fixed air-fuel mixture for which it can obtain the minimum for all exhaust gases emission [2]. This study can help in reducing fuel consumption, improving the quality of fuel combustion and reducing vehicle exhaust emissions in Nigeria