LAUTECH Journal of Engineering and Technology (LAUJET)
Not a member yet
571 research outputs found
Sort by
SOME NUTRITIONAL AND PHYSICAL CHARACTERISTICS OF KEREWA AND UC-82B TOMATO POWDER AS AFFECTED BY CONCENTRATION LEVELS OF FOAMING AGENTS AND MICROWAVE POWER USING FOAM MAT DRYING METHOD
No full text Moisture content of tomato (Licopersicon esculentum Mill.) is very high, so easily damaged due to physical impact, enzyme and microbes’ activity. Further processing is necessary in order to improve shelf life, one way is drying method. Tomato powder was produced from two varieties (Kerewa and UC-82B) using Foam mat drying method Glycerol Monostrate (GMS) and skimmed milk were used as forming agents at concentration level of 1%, 2% and 3% with Carboxyl Methyl Cellulose (CMC) as a stabilizer at different levels of microwave power (240W, 385W and 540W). The effects of concentration level and microwave power level was determined on quality and nutritional properties (colour, Rehydration ratio, lycopene and ascorbic acid) of the reconstituted tomato powder. The color change was affected by all factors with UC-82B variety having the maximum color change, indicating that Kerewa variety would be preferable in terms of color. Rehydration ratio for both varieties was constant for all levels of factors considered while Concentration levels did not significantly affect the properties. Microwave power affected the color change and ascorbic acid content of the finished products. There was an increased level of Color change and reduction in Ascorbic acid with increased power level. Lycopene contents in the final products was higher for skimmed milk as compared to GMS
ADSORPTION ISOTHERM, KINETIC AND THERMODYNAMIC STUDIES FOR REMOVAL OF TOTAL DISSOLVED SOLID FROM PAINT WASTEWATER USING ACID MODIFIED MUCUNA SHELL
Get PDFPresent study was conducted to investigate the removal of total dissolved solid (TDS) from paint wastewater (PW) by using eco-friendly biomass of phosphoric acid modified mucuna shell (MSA). Characterization of MSA is done by (i) proximate analysis (ii) surface chemistry by FTIR (iii) surface physical morphology by SEM technique (iv) structural analysis using X-ray diffractometer. Batch experiment was carried out to determine effect of parameters such as pH, biosorbent dose, contact time and temperature. Adsorption capacity of the experimental results was fitted into four isotherm model; Langmuir, Freundlich, Temkin and Dubinin-Radushkevich, but the Freundlich isotherm model was found to have higher correlation coefficient, implying MSA had heterogeneous surface. The adsorption kinetic has been described by pseudo-first-order, pseudo-second-order, Elovich and intra-particle diffusion model. It was observed that the rate of TDS adsorption follow pseudo-second-order model. Free energy of adsorption (?G^o), enthalpy (?H^o) and entropy (?S^o) changes are calculated to know the nature of adsorption. The calculated value of ?G^o at 303K-323K indicates that the adsorption process is spontaneous. From the calculation, values of ?H^o and ?S^oshows positive sign, which indicates that the adsorption process is endothermic in nature and the positive,?S^osuggested increased randomness at the solid/interface
OPTIMIZED PRODUCTION OF BIOETHANOL BY FERMENTATION OF ACID HYDROLYZED-CORN STOVER EMPLOYING SACCHAROMYCES CEREVISIAE YEAST STRAIN
Get PDFIn this study, corn stover was converted into ethanol using a locally-fabricated bioreactor and process conditions were optimized. The corn stover biomass used as substrate was milled, screened to 200 ?m and hydrolyzed with between 0.1-0.5 M HCl. The hydrolysis experiment was carried out for substrate concentrations of 20, 25, and 30% (w/v) of milled bagasse prepared in a 1000 mL glass jar containing distilled water. For each substrate concentration, the time, temperature, and acid concentration were varied between 10 – 60 min., 80 – 97 °C, and 0.1 – 0.5 M, respectively to find the optimum glucose yield. Glucose concentration in the optimum hydrolysate sample was determined using glucose oxidase method. Fermentation experiment was conducted in the bioreactor using 700 ml of the hydrolysate and Saccharomyces cerevisiae supplemented with minerals to yield ethanol of 21.47 g/L after 48 hours. A linear regression model developed after analysis of variance was able to predict the concentration of glucose produced during the acid hydrolysis, and the optimum ethanol yield of 21.47 g/L compares well with previous reported yield values found in literature
CHEMICAL AND MECHANICAL PROPERTIES OF LOW CARBON STEEL: INSIGHT FROM PROCESS PARAMETERS
Get PDFThe ability of steel bar to function well in structural applications is a function of its mechanical properties. Many factors account for the variations in the mechanical properties of low carbon steel. Therefore, understanding the influence of Physical and chemical compositions on their mechanical properties is essential for material development and applications. This study therefore, explored the effects of the section sizes ranging from 10mm - 16 mm in diameters. Chemical compositions of the steel samples were carried out using XRF. Tests samples were machined using lathe machine and their tensile, hardness and impact properties were determined. Results showed that their carbon contents ranged from 0.01% to 0.25% and the ultimate tensile strength and the yield strength properties decreased with increase in sample diameter. Hence, the diameters of the rods have great influence on the mechanical properties of the materials. The results of this study are relevant to steel industries that produce low carbon steel and structural engineers that make use of this steel in construction
EXPERIMENTAL DESIGN AND DEVELOPMENT OF LOCALLY MADE PARABOLIC TROUGH SOLAR THERMAL COLLECTOR UNIT
Get PDFThe design and analysis of Parabolic Trough Solar Thermal Collector (PTSTC) system used to generate hot/steam water for domestic and industrial purposes were carried out. The parametric studies were also conducted on the collector, study the effectiveness of hot water production for potential applications. The PTSC was designed with Parabolic Software version 2.0. The fabrication and design were done with a combination of reflector surface, reflector support, absorber pipe and wooden stand. The absorber pipe was painted in black colour while the trough was manually operated. The flow of water in the system follows the recycling process repeated during data acquisition. The ambient temperature, the inlet and outlet temperature of the receiver and total solar radiation on the PTSC were recorded. Different flow rate of the Heat Transfer Fluid (HTF) was tested at 0.021, 0.022, 0.023 and 0.024 kg/s respectively. Collected data showed the maximum outlet water temperature attained as 72oC. The average outlet temperature increased from 36oC at 10:30 hour to 69.84oC at 16:00 hour. The average beam radiation during the collection period was 699 W/m2. Different flow rates show that the lower the flow rate, the higher the efficiency of the system. The study revealed that the developed parabolic trough solar collector is viable for the production of sterilized water and low stage steam for domestic and industrial purposes
DEVELOPMENT OF AN INTELLIGENT WEB BASED DYNAMIC NEWS AGGREGATOR INTEGRATING INFOSPIDER AND INCREMENTAL WEB CRAWLING TECHNOLOGY
Get PDFThe World Wide Web is a rapidly growing and changing information source. This reality is gradually replacing the traditional way users obtain news or information. Traditionally, individuals get their news or information from print media, such as newspapers and magazines. Although, the advent of the internet has made things a lot easier by making this digitalized news accessible from anywhere in the world, either through news websites or dedicated applications. However, the growth and change rates make the task of finding relevant and recent information harder. Users are still faced with the challenges of visiting numerous websites just to get updated or informed on a specific type of news. This creates a problem as users have to always memorize different URLs and visit numerous websites just to view a specific type of news. Therefore, the need to develop an intelligent web based dynamic news aggregator that will provide a digital platform for individuals to easily find news pertaining to a particular topic in real time becomes imperative. It crawls the web, searches for news agencies and return a specific news of interest to the user. To address the shortcomings of existing news aggregators, this work was implemented by integrating the intelligent web based dynamic news aggregator, into an infospider web crawling technology. This is achieved applying a stochastic selector and incremental web crawling technology that crawls the entire seed urls. This system was implemented with the PHP scripting language developed to access the PHP-crawler using Aptana Studio as the Integrated Development Environment (IDE), Bootsrap3 and jQuery were used to provide a set of style sheets and JavaScript libraries to simplify the client-side scripting. The application was deployed and tested using the apache web server and a personal computer
DESIGN AND FABRICATION OF COMBINED ELECTROMAGNETIC AND MAGNETIC DRUM-BELT CONVEYOR SEPARATOR
Get PDFMineral processing operations are faced with many challenges which include effective separation of unwanted materials generated through the extraction process from the bulk material. Magnetic device is a machine used for separating magnetic materials from non-magnetic materials by inducing the magnetic flux. Magnetic and electromagnetic separators are widely used as primary separation equipment. This work was centred on the design and construction of a laboratory-sized dual purpose magnetic and electromagnetic separator for separating the magnetic particles from the rest of the bulk mineral or ferrous materials from foundry sand in a single system. The main components of the equipment include: the hopper, conveyor belt rotating drums, pulley and belt, electromagnet. The approaches to achieving the result reported include the design conceptualization, design calculation, design drawing using the AutoCAD and Inventor software, fabrication and assembly of components. The evaluation showed that electromagnetic separation is more efficient than magnetic separation. The equipment was fabricated at an average cost of 224,000:00 naira
SUSTAINABLE ENERGY ANALYSIS OF NIGERIAN ROAD TRANSPORTATION SECTOR: EFFECTS OF INFLUENCED FUEL DEMAND PATTERNS
Get PDFPetrol and diesel utilisations in the Nigerian road transportation sector have been assessed, using exergy efficiency and improvement potential as parameters. The mean petrol engine exergy efficiency was 13.05%, while that of diesel engines was 10.79%. The average improvement potential of petrol engines was 2.07×1011 MJ, which was 75.6% of average input exergy. Diesel engines had an average improvement potential of 5.15×1010 MJ, which was 69.2% of average input exergy. Practical constancy of the exergy efficiencies of the engines left input exergy values as the sole determining factors of improvement potentials of the systems. Petrol fuel was found to be utilised, away from sustainable path, more than diesel fuel. This observation was found attributable to subsidisation of petrol downstream sector and simultaneous deregulation of the diesel downstream sector as well as the preponderance of petrol engines in the road transportation sector. In conclusion, it was recommended that a mechanism be put in place to check the unsustainable petrol fuel utilisation in the transport sector
POWER SYSTEMS OPERATION IMPROVEMENT CONSIDERING LOSS MINIMIZATION AND VOLTAGE STABILITY ENHANCEMENT
Get PDFThe challenge of energy and power losses during electrical energy transmission from generation plants to users is a major problem that cannot be over-emphasized. These Losses are inevitable because they are inherent in the conduction of electrical energy through physical means but can be minimized. This paper presents a VSC-PSO method for optimizing the power system operation by simultaneously minimizing the loss and enhancing the voltage stability which are the objective functions. The optimal power flow (OPF) was performed on IEEE 30-bus system with Newton Raphson algorithm implemented in MATLAB simulation software. The simulation results showed that the VSC-PSO approach performed more excellently with concurrent consideration of line loss reduction and voltage stability improvement when compared with other methods in literatur
EXPLOITING GENETIC ALGORITHM IN STRING CASH DISPENSE DISPUTE
Get PDFThe cash transaction dispense dispute seems to be an ugly daily experience to bank customers. Most times the customers’ debited funds would not be auto reversed within the 24 hours given by inter-switch. At this point, customers have to report officially to their banks to get the problem sorted out manually by filling the dispute form. In some cases, after filling the form, they have to wait for at least seven business working days before the un-dispensed debited funds are reversed. This might be very excruciating on the customer, especially when un-dispensed cash is the only money on him/her. In this paper, our core interest is to solve the problem of delay in reversing debited funds using a genetic algorithm approach based on numerical integration. The result of the new system revealed how dispensed disputes are resolved within seconds without delay using the optimal fitness function values of the genetic algorithm that validates the customers’ claims and makes refunds. The system is independent of inter-switch and its flexibility allows customers to report their dispensed dispute online, especially when it is not reversed within allotted seconds. The research paper data set and the results were tested and analyzed using MATLAB software application