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Article
Publication date: 16 March 2011

M. Menkiti and O. Onukwuli

Coag-flocculation behavior of Brachystegia eurycoma coagulant (BEC) in respect of pH variation in coal washery effluent has been investigated at room temperature using various…

22

Abstract

Coag-flocculation behavior of Brachystegia eurycoma coagulant (BEC) in respect of pH variation in coal washery effluent has been investigated at room temperature using various dosages of unblended BEC. Coag-flocculation parameters such as order of reaction α, rate constant (K and Ks), coagulation period, τ1/2 e.t.c were determined. Turbidity measurement was employed using the single angle nephelometric method while BEC processing was based on work reported by Adebowale and Adebowale. Maximum parameter values are recorded at K of 6.6667×10-3m3/kg.s; dosage of (0.2 and 0.4kg/m3), pH2 and τ1/2 of 1.7293s while the minimum values are recorded at 5.00×10-4m3/kg.s, dosage of 0.3kg/m3, pH 6 and τ1/2 of 23.0572s. Minimum value of coag-flocculation efficiency is >98%; thus establishing BEC as a potential effective coag-flocculant. Parameters obtained lie within the range of previous works and confirm that the theory of perikinetics holds for coag-flocculation of the coal washery effluent using BEC at the experimental conditions.

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World Journal of Engineering, vol. 8 no. 1
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 20 February 2014

M. Menkiti and O. Onukwuli

Chitin Derived Coag-flocculant (CDC), is a cheap, abundant and eco-friendly deacetylated cationic polymer applied in this study at a pilot scale for the treatment of Brewery…

34

Abstract

Chitin Derived Coag-flocculant (CDC), is a cheap, abundant and eco-friendly deacetylated cationic polymer applied in this study at a pilot scale for the treatment of Brewery Effluent (BRE). The study investigates the influence of varying BRE pH on the coag-flocculation kinetics and behavior of the aggregation process at varying CDC dosages. The best coag-flocculation performance is recorded at rate constant, Km, of 0.0003 l/mg·min, half life, τ1/2, of 0.6846 min, pH of 4, dosage of 100 mg/l and efficiency, E (%) of 99.8791. Minimum efficiency (%) > 96 was achieved at 3 minutes of coag-flocculation, establishing CDC as an effective water treatment agent at the conditions of the experiment.

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World Journal of Engineering, vol. 10 no. 6
Type: Research Article
ISSN: 1708-5284

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Available. Open Access. Open Access
Article
Publication date: 16 December 2022

Uchenna Luvia Ezeamaku, Chinyere Ezekannagha, Ochiagha I. Eze, Nkiru Odimegwu, Angela Nwakaudu, Amarachukwu Okafor, Innocent Ekuma and Okechukwu Dominic Onukwuli

The impact of potassium permanganate (KMnO4) treatment on the tensile strength of an alkali-treated pineapple leaf fiber (PALF) reinforced with tapioca-based bio resin (cassava…

1695

Abstract

Purpose

The impact of potassium permanganate (KMnO4) treatment on the tensile strength of an alkali-treated pineapple leaf fiber (PALF) reinforced with tapioca-based bio resin (cassava starch) was studied.

Design/methodology/approach

The PALF was exposed to sodium hydroxide (NaOH) treatment in varying concentrations of 2.0, 3.7, 4.5 and 5.5g prior to the fiber treatment with KMnO4. The treated and untreated PALFs were reinforced with tapioca-based bio resin. Subsequently, they were subjected to Fourier transform infrared (FTIR) and tensile test analysis.

Findings

The FTIR analysis of untreated PALF revealed the presence of O-H stretch, N-H stretch, C=O stretch, C=O stretch and H-C-H bond. The tensile test result confirmed the highest tensile strength of 35N from fiber that was reinforced with 32.5g of cassava starch and treated with 1.1g of KMnO4. In comparison, the lowest tensile strength of 15N was recorded for fiber reinforced with 32.5g of cassava starch without KMnO4 treatment.

Originality/value

Based on the results, it could be deduced that despite the enhancement of bioresin (cassava starch) towards strength-impacting on the fibers, KMnO4 treatment on PALF is very vital for improved tensile strength of the fiber when compared to untreated fibers. Hence, KMnO4 treatment on alkali-treated natural fibers preceding reinforcement is imperative for bio-based fibers.

Details

Arab Gulf Journal of Scientific Research, vol. 41 no. 3
Type: Research Article
ISSN: 1985-9899

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Article
Publication date: 15 April 2014

M. Menkiti, C. Nwoye and O. Onukwuli

Chrysophylum albidium seed shell was utilized as an adsorbent for suspended and dissolved particle removal from coagulated coal washery effluent. Several parameters were…

26

Abstract

Chrysophylum albidium seed shell was utilized as an adsorbent for suspended and dissolved particle removal from coagulated coal washery effluent. Several parameters were investigated using batch mode and 23 full factorial central composite designs (CCD) (for optimization purposes). There exist single generality in optimal values for acid treated shell (ASAA) and salt treated shell (ASAS) at pH 6.8, 30°C, 10g/L dose, 30 min equilibrium time and 1g adsorbent mass for batch mode and CCD, respectively. Equilibrium data sufficiently fit the Langmuir isotherm (R2 > 0.99 and SSE (%) ≤ 0.093). Pseudo-second order kinetics provides best correlation (R2 > 0.99 and SSE (%) < 0.1) with experimental data. Thermodynamics constants (ΔG°, ΔH° and ΔS°) were respectively evaluated as -122.190 KJ/mol, 69005.967 J/mol and 228.146 Jmol-1K-1 for ASAA and -1537.455 KJ/mol, 68008.026 J/mol and 229.523 Jmol-1K-1 for ASAS. The shell biomass promises high potential as an efficient adsorbent since the adsorption process was favorable, endothermic and spontaneous.

Details

World Journal of Engineering, vol. 11 no. 1
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 15 June 2011

M. Menkiti, T. Chime and O. Onukwuli

Fluted pumpkin seed shell, an abundant and inexpensive natural resource in Nigeria, was used as a precursor to adsorbent production for the removal of suspended and dissolved…

38

Abstract

Fluted pumpkin seed shell, an abundant and inexpensive natural resource in Nigeria, was used as a precursor to adsorbent production for the removal of suspended and dissolved particle (SDP) from initially coagulated coal washery effluent (CWE). Key parameters such as contact time, adsorbent dose, pH and temperature were investigated using batch mode. The adsorption equilibrium, thermodynamics and kinetics of SDP on H3PO4 treated shell (FPA) and NH4Cl treated shell (FPS) were examined at specified temperatures. Equilibrium data sufficiently fit the Langmuir isotherm model (R2 > 0.99; SSE < 0.09). The pseudo-second order kinetic model provides the best correlation (R2>0.99;SSE<0.1) with the experimental data. The evaluated ΔG○ and ΔH○ indicate the spontaneous and endothermic nature of the process. This study demonstrates that pumpkin seed shell could be utilized as low cost, renewable, ecofriendly bioadsorbent for the removal of SDP from CWE.

Details

World Journal of Engineering, vol. 8 no. 2
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 17 April 2023

Uchenna Luvia Ezeamaku, Innocent Eze, Nkiru Odimegwu, Angela Nwakaudu, Amarachukwu Okafor, Okechukwu Dominic Onukwuli and Ikechukwu Abuchi Nnanwube

The purpose of this study is to investigate starch mucor (SM) in potassium iodide (KI) as corrosion inhibitor of aluminium in hydrochloric acid (HCl) medium.

67

Abstract

Purpose

The purpose of this study is to investigate starch mucor (SM) in potassium iodide (KI) as corrosion inhibitor of aluminium in hydrochloric acid (HCl) medium.

Design/methodology/approach

The SM in KI was characterized by gravimetric, scanning electron microscopy, electrochemical impedance spectroscopy measurements, potentiodynamic polarization and gas chromatography-mass spectrometer techniques. The inhibition efficiency was optimized using response surface methodology.

Findings

The result revealed that the inhibitor inhibited corrosion at a low concentration with the rate of inhibition increasing as the concentration of the inhibitor increased. The inhibition efficiency increases as the temperature was increased with slight incorporation of the inhibitor (SM in KI). This indicates that the corrosion control is both inhibitor (SM in KI) and temperature dependent.

Originality/value

The research results can provide the basis for using SM in KI as corrosion inhibitor of aluminium in HCL medium. Mixed-type inhibitor nature of SM was proved by cathodic and anodic nature of the polarization curves.

Details

Pigment & Resin Technology, vol. 53 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 13 February 2017

Ali Bahadir, Turgay Kar, Sedat Keles and Kamil Kaygusuz

The purpose of this paper is to investigate fast pyrolysis of maple fruit as an energy sources. This could serve as a solution to the energy sources problem.

238

Abstract

Purpose

The purpose of this paper is to investigate fast pyrolysis of maple fruit as an energy sources. This could serve as a solution to the energy sources problem.

Design/methodology/approach

Fast pyrolysis of maple fruit (samara) was achieved in a fixed bed reactor. The pyrolysis experiments have been conducted on the sample of maple seeds to particularly determine the effects of pyrolysis temperature, particle size and sweep gas flow rate on the pyrolysis product yields.

Findings

The oil of maple fruit from fast pyrolysis has good properties to be a potential candidate as a biofuel or as a source of chemicals. In addition to being environmentally desirable, it can reduce the energy cost, e.g. that Turkey imports a majority of its energy.

Originality/value

The use of maple fruit for fast pyrolysis and pyrolysis conditions impact on the yields of pyrolysis liquid can be considered as novel aspects of this paper.

Details

World Journal of Engineering, vol. 14 no. 1
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 28 April 2014

Weiwei Zhang, Xianlong Jin and Zhihao Yang

The great magnitude differences between the integral tunnel and its structure details make it impossible to numerically model and analyze the global and local seismic behavior of…

524

Abstract

Purpose

The great magnitude differences between the integral tunnel and its structure details make it impossible to numerically model and analyze the global and local seismic behavior of large-scale shield tunnels using a unified spatial scale, even with the help of supercomputers. The paper aims to present a combined equivalent & multi-scale simulation method, by which the tunnel's major mechanical properties under seismic loads can be represented by the equivalent model, and the seismic responses of the interested details can be studied efficiently by the coupled multi-scale model.

Design/methodology/approach

The nominal orthotropic material constants of the equivalent tunnel model are inversely determined by fitting the modal characteristics of the equivalent model with the corresponding segmental lining model. The critical sections are selected by comprehensive analyzing of the integral compression/extension and bending loads in the equivalent lining under the seismic shaking and the coupled multi-scale model containing the details of interest is solved by the mixed time explicit integration algorithm.

Findings

The combined equivalent & multi-scale simulation method is an effective and efficient way for seismic analyses of large-scale tunnels. The response of each flexible joint is related to its polar location on the lining ring, and the mixed time integration method can speed-up the calculation process for hybrid FE model with great differences in element sizes.

Originality/value

The orthotropic equivalent assumption is, to the best of the authors’ knowledge, for the first time, used in the 3D simulation of the shield tunnel lining, representing the rigidity discrepancies caused by the structural property.

Details

Engineering Computations, vol. 31 no. 3
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 11 September 2020

Ernest Mbamalu Ezeh and O.D. Onukwuli

The purpose of this paper is to observe the effect of cheap cow horn ash particles (CHAp) filler as a possible replacement for expensive fillers on the mechanical properties of…

97

Abstract

Purpose

The purpose of this paper is to observe the effect of cheap cow horn ash particles (CHAp) filler as a possible replacement for expensive fillers on the mechanical properties of polyester-banana peduncle fibre (BPF) composites were evaluated using standard procedures.

Design/methodology/approach

Composite was developed using CHAp as a filler component, polyester resin and BPF, with the filler of varying percentage weights (5%, 10%, 15% and 20%), at particle sizes of 125 µm, using hand lay-up technique. The physicochemical properties of CHAp were examined through x-ray fluorescence (XRF), X-ray diffractometer (XRD), transmission electron microscopy, scanning electron microscope, energy dispersion spectrometric analysis (EDS) and density. Mechanical properties of the developed composites were also examined.

Findings

The results showed that the tensile properties and impact strength of the composites reduced marginally with the incorporation of the cow horn ash particle as a filler. However, the flexural strength of the composites increased progressively with the incorporation of BPF as the fibre loading increased. The major constituents of CHAp were CaO from XRF study, calcite (CaCO3) from XRD study and Ca in EDS study in accordance with the analytical parameter, which showed a major component of calcium. The high value of CaCO3 in CHAp improved flexural and impact strengths of the composites. CHAp presented around solid and irregular shape particle characteristic of most fillers with an average particle size of 98.13 nm. The tensile and flexural strengths of the polyester matrix composites obtained at 7.5% BPF: 7.5% CHAp was 117.87 MPa depicting satisfactory mechanical characteristics.

Originality/value

Generally, cow horn ash particle exhibited adequate filler component potential in composite production in keeping with its property effects on the mechanical properties of polyester-BPF composites.

Details

World Journal of Engineering, vol. 17 no. 6
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 19 June 2019

Ali Akbar Abbasian Arani, Ali Arefmanesh and Hamidreza Ehteram

The purpose of this paper is to recommend a validated numerical model for simulation the flue gases heat recovery recuperators. Due to fulfill of this demand, the influences of…

208

Abstract

Purpose

The purpose of this paper is to recommend a validated numerical model for simulation the flue gases heat recovery recuperators. Due to fulfill of this demand, the influences of ash fouling characteristics during the transient/steady-state simulation and optimization of a 3D complex heat exchanger equipped with inner plain fins and side plate fins are studied.

Design/methodology/approach

For the particle dispersion modeling, the discrete phase model is applied and the flow field has been solved using SIMPLE algorithm.

Findings

According to obtained results, for the recuperator equipped with combine inner plain and side plate fins, determination of ash fouling characteristics is really important, effective and determinative. It is clear that by underestimating the ash fouling characteristics, the achieved results are wrong and different with reality.

Originality/value

Finally, the configuration with inner plain fins with characteristics of: di =5 mm, do = 6 mm, dg = 2 mm, dk = 3 mm and NIPFT = 9 and side plate fins with characteristics of: TF = 3 mm, PF = 19 mm, NSPF = 17·2 = 34, WF = 10 mm, HF = 25 mm, LF = 24 mm and ß = 0° is introduced as the optimum model with the best performance among all studied configurations.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 5
Type: Research Article
ISSN: 0961-5539

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