Open Access Original Research Article

Removal of Hexavalent Chromium from Aqueous Solution Using Unmodified Saw Dust: Batch and Column Studies

C. Tsamo, I. Bachirou, I. Samomssa, T. B. Fouogoung

Current Journal of Applied Science and Technology, Page 1-16
DOI: 10.9734/CJAST/2019/46153

The effects of contact time at three initial concentrations and temperature in batch process and the effects of three initial concentrations and three bed heights in column process were used to evaluate the potentials of unmodified saw dust, a low cost adsorbent in removing Cr(VI) with highly mutagenic and carcinogenic properties from aqueous solution. The material characterized using point of zero charge, FTIR and Scanning Electron Microscopy (SEM) showed that it has good adsorbent properties. Nearly 99% of Cr(VI) was removed in two minutes attaining equilibrium in five minutes for all the initial concentrations tested in batch operation. Langmuir and Dubinin-Radushkevich (D-R) isotherms best fitted the adsorption with maximum adsorption capacities of over 196 mg/g. Adsorption on unmodified saw dust can be physical, ion exchange and chemical depending on the initial concentration and the process is spontaneous and endothermic. The removal efficiency increases with increasing bed height but decreases with increase initial concentration, however, adsorption capacity increases with increase in initial concentration but decreases with increase bed height for column operation. Thomas kinetic model best described the column adsorption over other tested model. Unmodified saw dust can effectively remove Cr(VI) from wastewater in batch and column operations.

Open Access Original Research Article

Assessment of Cassava Effluent Contaminated Soil in Ohimini L.G.A, Benue State, Nigeria

Onyeke Ochu, Amali Okwori

Current Journal of Applied Science and Technology, Page 1-6
DOI: 10.9734/CJAST/2019/44289

Ohimini local government area is famous for its cassava processing cottage industries in benue state. The processing of cassava tubers into garri incurs large volumes of waste fluid (effluents) that contaminates the soil around such areas. Therefore the study is aimed at assessing the impact of cassava wastewater on soil quality at selected garri processing areas of benue state. The study was carried out at five wards within ohmini local government area during the dry season in june, 2017. Exchangeable bases, ph, % organic carbon, % organic matter and cyanide levels of soils receiving the wastewater (impacted) as well as soils not receiving  wastewater (control) were analysed according to standard methods and variations were observed. Impacted soil had a foul smell and strongly alkaline (8.59) with a ph value ranged at (7.35-9.25), cyanide levels ranged at (1.22-4.16), % organic carbon and %organic matter ranged at 0.60-2.07 and 1.69-6.50 respectively. All parameters analysed had higher values at impacted soil than the control samples except potassium(k). Cassava wastewater alters soil properties, therefore with the large number of individuals carrying out this activity thus, it is necessary to analyse soil properties in such areas to curb or halt further alterations of the soil in the area.

Open Access Original Research Article

Influence of Storage Conditions on Fuel Functionality of Palm Oil Methyl Ester

S. Nandi, J. Singh, S. Gangil

Current Journal of Applied Science and Technology, Page 1-14
DOI: 10.9734/CJAST/2019/46270

The stability of biodiesel generally depends on the nature of the fatty acid composition of the parent oil. Unsaturated compounds are significantly more reactive to oxidation than saturated compounds. The palm olein vegetable oil, derived from crude palm oil, contains higher unsaturated compounds in comparison to other forms of palm oils. An experiment was intended to investigate the impact of storage degradation of palm oil methyl ester in terms of fuel chemical properties, engine performance and exhaust emission. The degradation study was carried out by keeping methyl ester of palm oil, derived from raw palm olein oil through base catalytic trans-esterification, in two different environment conditions (one in a transparent closed-lid container exposed to light and another in a container exposed to air and light) at three different temperature (5°C, 25°C and 38°C) over 10 months. It was observed that degradation of biodiesels through oxidative reaction led to a series of changes in its properties, with severely increase in peroxide value, acid value and decrease in heating value at higher temperature storage irrespective of storage conditions. The fuel sample with the highest degradation rate, after 10 months of storage, was considered for the evaluation of engine performance and emission by making blends with petroleum diesel at a different proportion. And the comparisons were made with fresh biodiesel blends and diesel fuel.  The engine performance of the biodiesels (fresh and oxidized) and their blends were similar to that of diesel fuel with a non-significant difference in thermal efficiency, but higher fuel consumption. The emission quality (CO and smoke density) of oxidized biodiesel was significantly better than that of fresh biodiesel and diesel fuel. But, the NOx emission was comparatively higher than diesel fuel for both the biodiesel. The effect of fuel oxidation on the NOx emissions was also found to be 3% to 4% higher.

Open Access Original Research Article

Implementation Evaluation Metrics for Enterprise Resource Planning Solution – A Case of Kibabii University

Samuel Mungai Mbuguah, Franklin Wabwoba, Chrispus Kimengich Wanjala

Current Journal of Applied Science and Technology, Page 1-9
DOI: 10.9734/CJAST/2019/46085

Most institution of higher learning are implementing and Enterprise Resource planning (ERP) in automating various activities. The architecture of most of the ERP is based on the Service Oriented Architecture (SOA) where each module can be called as service. In most of the contract signed between the vendor and the university, payment is tied to the level of implementation. The Question is how to then measure the level of implementation? This paper proposes a metric that could be used in evaluation of the degree of implementation. The metric was derived based on an acceptance test on each of functionality of module as per terms of reference. The result of a test was rated as a Fail, Pass, or Query The result was then coded such that a fail was assigned a zero (0), pass one (1) and query a half (½). From which a metric was derived which measures the level implementation.

Open Access Original Research Article

Modelling the Condensed Water Discharge Rate in an Air Conditional System in South West, Nigeria

O. S. Bamisaye, P. K. Oke

Current Journal of Applied Science and Technology, Page 1-13
DOI: 10.9734/CJAST/2019/46188

Aims: This work is aimed at developing an empirical model for predicting condensed water discharge rate in an air conditional system, most especially in Nigerian offices.  

Study Design: Quantitative study. Relevant data on condensate discharge rate was collected.

Place and Duration of Study: An office located within the School of Engineering and Engineering Technology Building of the Federal University of Technology, Akure, Ondo State, Nigeria, between November 2015 to April 2016.

Methodology: The method used consists of data collection and readings such as condensate volume, dry bulb temperature, relative humidity, sensible heat ratio, and dew point temperatures. A split type air-conditioning unit with a cooling capacity of 2500 W, using refrigerant and rated air flow rate of 400 m3/hr was used to determine the amount of condensate rate.

Results: The result of six-month data collected showed that a total of 528 L of condensed water was collected at the split type air conditional unit. The highest condensate discharge rate of 1.07 L/hr was recorded on 6th and 7th April 2016. The coefficient of determination, R2, obtained for first, second and third order multiple linear regression model were 0.964, 0.9793, and 0.9803 respectively. The developed multiple linear regression model was used to compare the experimental and predicted values of the condensate from the air conditional unit used for the study.

Conclusion: The developed model offers ease of prediction and forecasting of the amount of condensate discharge rate. This study confirms that relative humidity, sensible heat ratio, dry bulb temperature, and dew point temperature are the most significant factors contributing to an increase in condensate discharge rate.

Open Access Original Research Article

Mass and Energy Balance Analysis of Pneumatic Dryers for Cassava and Development of Optimization Models to Increase Competitiveness in Nigeria

S. A. Adegbite, A. Abass, O. J. Olukunle, A. P. Olalusi, W. B. Asiru, W. Awoyale

Current Journal of Applied Science and Technology, Page 1-11
DOI: 10.9734/CJAST/2019/46215

The use of locally fabricated flash drying system is a major challenge for the production of High Quality Cassava Flour (HQCF). Thus, this study focuses on analysis of pneumatic dryers for cassava processing and its significance relates to its promise to further our understanding of the performance of the existing design models of pneumatic dryers and to identify new way to improve drying performance of the dryers. Four different design models of pneumatic dryer for HQCF drying were evaluated at three cassava processing centers. The dryers were subsequently modified based on minimum air. The dryer models were assessed based on energy efficiency, specific heat consumption and thermal efficiency. The highest energy efficiency was recorded for the positive, single cyclone system, dryer model 2 (+1C) which increased from 63.27 to 78.55% while its specific heat consumption was reduced from 3.79 to 3.06 MJ/kg after modification. Furthermore, the modification reduces the fuel consumption in all the dryer models by 22%, 14%, 14% and 16% respectively. Thus, it is established that the positive, single cyclone system had the better drying performance of all the dryer models evaluated.

Open Access Original Research Article

Analytical Design Method for Widening the Intertrack Space

Wladyslaw Koc

Current Journal of Applied Science and Technology, Page 1-13
DOI: 10.9734/CJAST/2019/46393

Widening the intertrack space is one of the basic elements of shaping the geometric layout of the railway track. It significantly influences the obtained speed of trains. The solutions applied so far do not provide favorable kinematic conditions due to the occurring distribution of curvature along the length of the track. In the paper a new approach is made to the problem of widening the intertrack space by presenting a thesis that it is necessary to form it using two joined curves of appropriate curvature distribution. It has been assumed that along the widening length there appear segments of variable curvature in extension zones of both the curves, whereas in the central zone the curvature is constant. To solve the problem use has been made of the analytical design technique, employing the identification of the curvature distribution by different equations. Particular attention has been given to the nonlinear distribution of curvature, regarded as the most advantageous undertaking. To obtain a specific final ordinate in the widening the intertrack space it is necessary to obey a sequential correction procedure of the adopted geometric parameters.

Open Access Original Research Article

Effect of Activated Carbon on Re-Conversion Reaction of Cu/LiCl/C Electrode with LiPF6/Methyl Difluoroacetate Electrolyte

Katsuo Hashizaki, Shinsaku Dobashi, Shigeto Okada, Toshiro Hirai, Jun-ichi Yamaki, Zempachi Ogumi

Current Journal of Applied Science and Technology, Page 1-12
DOI: 10.9734/CJAST/2019/46501

Transition-metal chlorides are known to suffer from dissolution in organic solvents. However, our previous investigation revealed that in the Li/CuCl2 battery, the dissolution of CuCl2 cathode materials could be suppressed by using LiPF6/methyl difluoroacetate (MFA; CHF2COOCH3) electrolyte. And, the Cu/LiCl electrode could both charge and discharge in LiPF6/methyl difluoroacetate (MFA) electrolyte as the re-conversion reaction cathode of Li/CuCl2 battery. However, the capacity is only half the theoretical value of 399 mAh g–1. This is because cuprous is hardly oxidized to cupric during charging due to copper disproportionation reaction.

In this study, activated carbon was added to the Cu/LiCl electrode in order to promote the production of CuCl2, and to improve the capacity. The physical properties of the activated carbon were found to have significant effects: activated carbon with a large specific surface area and micropore volume enabled CuCl2 deposition, and improved the capacity of the Cu/LiCl/C electrode to approximately 300 mAh g–1.