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1.
Heliyon ; 7(3): e06398, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33732932

RESUMO

This study presents a review of sources and atmospheric levels of anthropogenic air emissions in Nigeria with a view to reviewing the existence or otherwise of national coordination aimed at mitigating the continued increase. According to individual researcher's reports, the atmospheric loading of anthropogenic air pollutants is currently on an alarming increase in Nigeria. Greater concerns are premised on the inadequacy existing emission inventories, continuous assessment, political will and development of policy plans for effective mitigation of these pollutants. The identified key drivers of these emissions include gas flaring, petroleum product refining, thermal plants for electricity generation, transportation, manufacturing sector, land use changes, proliferation of small and medium enterprises, medical wastes incineration, municipal waste disposal, domestic cooking, bush burning and agricultural activities such as land cultivation and animal rearing. Having identified the key sources of anthropogenic air emissions and established the rise in their atmospheric levels through aggregation of literature reports, this study calls for a review of energy policy, adoption of best practices in the management air emissions and solid wastes as well as agriculture and land use pattern which appear to be the rallying points of all identified sources of emission. The study concluded that the adoption of cleaner energy policies and initiatives in energy generation and usage as against pursuit of thermal plants and heavy dependence on fossil fuels will assist to ameliorate the atmospheric loadings of these pollutants.

2.
Heliyon ; 6(11): e05384, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33210001

RESUMO

Incorporating chicken feather fibre (CFF) into natural based-nanocomposite comprising of glycerine plasticized-cassava starch binder with bentonite (BNT) as nanofiller, a thermal insulator (TIN) was synthesized. Central Composite Design (CCD) Response Surface Methodology was employed to carry out the experimental design using two factors (CFF and BNT) along with one response (thermal conductivity) to produce nine materials as insulators, comprising of 0%, 5%, and 10% BNT based on 8 g initial weight of CFF. A sample without CFF was used as the control. Developed thermal insulators were subjected to thermal conductivity tests using Lee's disc method at a steady state. The best insulator is TIN-4 with the lowest thermal conductivity of 0.0313 W/(mK) and the highest insulation property of 114.63 m2k/W, while TIN-10 with no CFF has the highest thermal conductivity of 0.0549 W/(mk) and lowest insulation property of 48.1603 m2k/W. Proportionate use of chicken feather fibre in starch-clay nanocomposite will help synthesize an effective thermal insulator with minimum cost.

3.
Data Brief ; 31: 105804, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32577450

RESUMO

More than 1.3 billion tons, a third of the total food produced, is wasted annually, and it has been predicted to increase in the coming years. Food waste significantly contributes to greenhouse gas (GHG) emissions resulting in the release of about 3.3 billion tonnes of CO2 into the environment yearly. Hence this large amount of wastes, with adverse environmental effects, needs to be appropriately managed. New technologies such as Anaerobic digestion, fermentation, and gasification are being used to produce renewable energy, which in turn reduces the increasing level of food wastes in the environment. Pyrolysis of biomass materials or food wastes produces high-value energy products or bio-oil that can possibly replace non-renewable fossil fuels when it is upgraded. In this study, pyrolysis (thermal treatment in the absence of oxygen) of plantain and yam peels to produce bio-oil, was investigated. The pyrolysis conditions, wide temperature ranges at an interval of 100 °C (200-700 °C), absence of a catalyst (AOC), the use of zeolite -Y catalyst using two separate heterogeneous catalysis procedures were imposed and used to produced bio-oil. In the first procedure, the pyrolysis gases were allowed to rise through a zeolite-Y catalyst bed (HTC). And in the second procedure, the plantain or yam peel feedstock was first mixed uniformly with the zeolite-Y catalyst before pyrolysis (HMC). The GC-MS machine was used to analyze or characterize the obtained bio-oil while proximate analysis and XRF machine were used to characterize the plantain and yam peels feed. The residue, biochar, from the pyrolysis process, was also characterized using the XRF machine.

4.
Ecotoxicol Environ Saf ; 198: 110656, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32334203

RESUMO

The occurrence and distribution of microplastics (MPs) for two seasons (dry and raining) were investigated based on 10 sections of OX- Bow Lake Yenagoa, Nigeria for surface water and sediments. MPs were abundant in colour and dominated by fibrous items. For dry season, Polyethylene terephthalate (PET) and Plasticised polyvinyl chloride (Plasticised PVC) were the predominant MPs; they both account for 72.63% and 10.9% of surface water and sediment samples. The raining season accounted for Plasticised (PVC) 81.5% and low-density polyethylene 4.2% respectively. The raining and dry seasons MPs were characterise by µ-FTIR. Beads and pellets were most common MP shapes in both water and sediment samples for the two seasons. The results showed that there is high presence of MPs in OX -Bow Lake.


Assuntos
Sedimentos Geológicos/química , Lagos/química , Microplásticos/análise , Polietileno/análise , Chuva , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Nigéria , Estações do Ano
5.
Data Brief ; 24: 103867, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30976639

RESUMO

Central composite design (CCD) approach of the response surface methodology design of experiment was adopted to determine the production of fermentable sugars after enzymatic conversion of alkaline peroxide oxidative pretreated sugarcane bagasse lignocellulose. MINITAB 16 statistical software was used to design the experiments, evaluate and interpret data generated during the process. The effects of factors such as time, hydrogen peroxide concentration, and temperature on treated biomass for reducing sugars (RS) production were investigated. Operating pretreatment conditions (low-high design levels) were reaction time (6-10 h), hydrogen peroxide concentrations (1-3%v/v), and reaction temperature (60-90 °C). With the desirability of optimization of 1.000, optimal reducing sugar yield after enzymatic hydrolysis was validated to be at 100.2 °C, reaction time of 4.6 h, and hydrogen peroxide concentration of 0.3% with optimum RS yield of 153.74 mg equivalent glucose/g biomass.

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