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- ItemOpen AccessPersonal exposures to particulate matter in various modes of transport in Lagos city, Nigeria(Cogent Enviromental Science, 2016-11-17) Odekanle, Ebenezer Leke; Fakinle, Bamidele Sunday; Akeredolu, F.A; Sonibare, JacobUrban air pollution continues to be a major problem in Nigerian cities. Most studies of air pollution in Nigeria have concentrated on the background air quality and its eects on people outside vehicles. However, it has been suggested that in-vehicle pollution is often worse than pollution outside the vehicle. This study focuses on personal exposures to PM10 and PM2.5 in various modes of transportation in Lagos city. Six roadways which are representative of commercial, industrial, and residential areas of the city were selected. Measurements were made inside four major modes of transportation in the city: cars, buses, Bus Rapid Transit (BRT), and walking for PM10 and PM2.5. Measurements were done for each mode twice a day (morning and afternoon) for 12days. The highest average PM10 and PM2.5 concentra- tions were measured for pedestrian (476.35 and 216.60μg/m3, respectively) dur- ing rush hours. The result showed that pedestrians were found to be exposed to the highest average PM10 and PM2.5 concentrations, while commuters in cars, BRT and buses were exposed to respective decreasing concentrations of PM10. Similarly, commuters in BRT were exposed to the lowest concentrations of PM2.5 regardless of time of day. The results obtained were much higher than the results for London but comparable to Mexico city and Taiwan’s results. This study has provided information that can help commuters to choose appropriate travel behavior that can minimize their exposure to particulate matter
- ItemOpen AccessPeriodic characterization of alkylnaphthalenes in stack gas and ambient air around a medical waste incinerator(Springer-Verlag GmbH Germany, 2017) Adesina, Olusola Adedayo; Sonibare, Jacob Ademola; Diagboya, Paul N.; Adejuwon, Adesuji; Famubode, Temitope; Bello, Josiah O.Due to the subtle occurrence of environmental polycyclic aromatic hydrocarbon (PAHs) pollution from incinerators, it is seldom considered a significant source of PAH pollution. However, considering the recent build-up of toxics in urban air, this may be a serious concern around the incinerator vicinity due to the potential consequences of PAHs on human health.Hence, this study determined 11 alkyl-naphthalene contributions from a hospital waste incinerator (HWI_0) into ambient air receptor points (HWI_1 to HWI_5) for a 1-year period: June 2014–May 2015. The HWI_0 and ambient gases were sampled using filter-sorbent sampling system and polyurethane foam (PUF) passive samplers, respectively, and all alkyl-naphthalenes were determined using GC-MS. Results showed that the source concentrations were in the range of 0–14.0 ng/m3 and generally higher than the receptor points. The receptor point concentration trends were mainly HWI_1 > HWI_2 ≥ HWI_3 ≥ HWI_5 ≥ HWI_4. Multivariate receptor model analysis suggested high correlations between source and the receptor points though there might be some significant contributions from other emission sources. The average monthly concentrations (Σalkyl-naphthalene) at HWI_0 and the receptors HWI_1, HWI_2, HWI_3, HWI_4 andHWI_5were 67.4 ± 24.3, 57.9 ± 20.1, 42.8 ± 16.9, 39.7 ± 12.2, 36.5 ± 22.2 and 37.8 ± 15.4 ng/m3, respectively. Though these concentrations were lower than the estimated minimal risk level (MRL) for chronic inhalation exposure to naphthalene and its derivatives 0.003 mg/m3, continuous exposure to these pollutants might result in chronic effects. Finally, this study may be used to evaluate the environmental contribution of alkyl-naphthalenes from typical medical waste incinerator in Nigeria.
- ItemOpen AccessGround level concentration of some air pollutants from Nigeria thermal power plants(Taylor & Francis, 2016-08-12) A. J, Adesanmi; Bamidele Sunday, Fakinle; Jamiu Adetayo, Adeniran; Rafiu Olasunkanmi, YusufPower sector in Nigeria is undergoing structural reforms aimed at improving and expanding the current generation capacity, using thermal power plants. Ground level concentrations of air pollutants emitted from natural gas-powered thermal power plants were estimated using the American Meteorological Society-Environmental Protection Agency Regulatory Model (AERMOD). The average 24-h ground level concentrations of CO, NOx, SO2, particulate matter (PM), and volatile organic compounds (VOCs) were 31.88–72.79; 61.33–104; 0.61–3.91; 0.21–1.52; and 0.19–1.09 µg/m3, respectively. There is need for continuous monitoring of ground level concentration of pollutants around the thermal power plants to guarantee the safety of the environment in the host communities
- ItemOpen AccessEstimation of sulphur dioxide emission from consumption of premium motor spirit and automotive gas oil in Nigeria(Cogent Environmental Science, 2017-05-17) Okedere, O.B.; Ajala, Olawale E.; Sonibare, Jacob; Adesina, OlusolaAbstract: This paper estimated the annual levels of sulphur dioxide (SO2 ) from consumption of premium motor spirit (PMS) and automotive gas oil (AGO) across the States and Regions of Nigeria. This was with a view to estimating the per capita and land distributions of emissions. Annual fuel consumption, average fuel sulphur contents and emission factors were combined to estimate the annual levels of SO2 . Per capita and land distributions of emissions were then established using population and land area, respectively. Results showed that Lagos and Ogun States had the maximum SO2 emissions from consumption of PMS and AGO, respectively, in 2012. Between 2001 and 2014; most of the SO2 emissions from consumption of PMS and AGO came from the South-western and South-southern regions of the country, respectively. Based on projected future fuel consumption, annual SO2 emissions from utilization of PMS and AGO are projected to further increase over their 2014 estimates. Interim measure suggested for mitigation of SO2 emission is the importation of refined products with highly reduced sulphur contents. Medium to long-term measures include building of more refineries locally to make use of Nigeria’s crude oil which is generally low in sulphur content and a massive improvement in the country’s energy generation so as to lower the demand pressure on refined petroleum products.
- ItemOpen AccessEffect of Emulsification Process Conditions on the Properties of Water-in-Bitumen Emulsion( Journal of the Japanese Association for Petroleum Technology, 2017-01) Alade, Lekan; Yuichi, Sugai; Sasaki, Kyuro; Ademodi, BayoSteam or hot water injection into the bitumen reservoir leads to the formation of water-in-bitumen emulsions which exhibit higher viscosity compared to the original bitumen; and thereby affects production flow. The understanding of the effect of formation process conditions on the nature of this emulsion could assist in production improvement, design and simulation of post-production separation system. In this work, water was dispersed in bitumen phase at different temperatures (50-180°C) and mixing speeds (11.7-23.3s⁻¹). Emulsification properties such as percentage emulsification (extent of water dispersion into the bitumen), and the particle size of emulsion were analyzed to evaluate the effects of the process conditions. Ultimately, correlations have been presented to predict emulsion properties from the process conditions