LAUTECH Journal of Engineering and Technology (LAUJET)
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OPTIMIZATION OF PROCESS PARAMETERS FOR NATURAL GAS SWEETENING USING ASPEN HYSYS AND RESPONSE SURFACE METHODOLOGY
Get PDFAmines process remains the most economic and efficient technology available today for the removal of acid gases. However, the costs associated with pumping higher flow rates and cost of increased energy needs for the regeneration of solution can undermine the economic feasibility of the project portfolio. The absorber pressure, the composition and temperature at which the sour gas is available dictates sour gas and amine flow rates needed to meet the sweet gas specifications. To improve absorber capacity for a given sweet gas specification, optimization are commonly carried out using spread sheet with an adjust function to manipulate sour gas flow rate for fixed amine flow rate. This study performed optimization using response surface methodology on a simulated and calibrated amine plant. The result shows that the optimum operating conditions for 96% CO2 removal were temperature of 30 oC, mass flow rate of 868.75 kg/hr and 20 numbers of plates. In conclusion, using experimental design and response surface methodology the parameter manipulation for attainment of optimal conditions is overcome
ASSESSMENT OF NOISE POLLUTION IN HIGH DENSITY AREA OF ILORIN METROPOLIS
Get PDFNoise is an environmental pollutant that has continue to increase with an increase in population, Urbanization, and the general desire of man to acquire advanced technologies in transportation, construction, recreation and entertainment among others. In an attempt to provide solutions that will ameliorate pollution problem in urban centres of developing nations especially, the present study investigated the sources of noise pollution in very busy areas. Four very busy areas of Ilorin metropolis, Nigeria were randomly selected and used as case studies of a typical noise polluted city of a developing nation. Noise assessment quantities such as LAeq, L10, L90 TNI, LNP LD LN and LDN were used to assess and establish the background noise, peak noise and dominant noise sources at these locations. Results of this study shows that the major source of noise pollution in Ilorin metropolis can be attributed to traffic, where the TNI ranged between 88 - 120 dB (A), and LNP from 86 – 107 dB (A). Other intrusive sources of noise pollution at the studied locations could be attributed to the noise from business transactions, roadside media operators, individual electricity, hawkers advertising their wares and indiscriminate use of public address systems (PBS) for business promo and religious activities. Results show that the areas under study were noise polluted as they exceeded the standard provided by the world health organization (WHO)
MODELLING OF A PRE-HOSPITAL EMERGENCY CARE FLOW PROCESS USING TIMED COLOURED PETRI NETS
Get PDFPre-hospital emergency care service is a major gateway to the Accident and Emergency Department that determines the rate of quality emergency service in hospitals. In this paper, Timed Coloured Petri Nets (TCPN) formalism is employed to model a pre-hospital emergency care flow process which is characterized by ambulance localization and emergency call responses using Osun State Emergency Management Ambulance Service (O’ambulance) as a case study. The developed TCPN model consists of Next Arrival Call (NAC) and Process Emergency Call (PEC) modules. The NAC module abstracted the emergency calls that were received by one (1) call receiver agent being utilized while the PEC module abstracts the operation (services) carried out in the units. The developed TCPN model was simulated using Coloured Petri Nets (CPN) tools while its validation was explored by comparing the simulated and actual rescue team average response time and turn-around times of the rescue teams in operation at the considered case study. The simulation results of the developed TCPN model yielded maximum Average Waiting Times (AWT) of 1.65 and 0.35 minutes using one and two emergency call receiver agents, respectively. Also, the simulation results showed that 7.05, 26.17 and 35.13 minutes were recorded as minimum values for Rescue team Average Response Time (RART), Rescue team Turn-around Time in case of non-critical (RTTNC) and Rescue team Turn-around Time Critical (RTTC), respectively. Similarly, the simulation results showed that RART, RTTNC and RTTC yielded maximum values of 15, 34 and 41.62 minutes, respectively. Statistically, there were no significant differences between the simulated and the real number of patients entering the health centre at 5% level. This gave a confirmation that the developed TCPN model accurately described the pre-hospital emergency care flow process under study. The developed TCPN model could serve as a referential model for studying and improving pre-hospital emergency care flow process in a named ambulance centre
OPTIMIZATION OF PROCESSING PARAMETERS AND QUALITY ATTRIBUTES OF FRIED COCOYAM CHIPS
Get PDFThe influence of frying temperature and time on the quality characteristics of deep-fat fried cocoyam chips was investigated using Central Composite Design (CCD) in Response Surface Methodology (RSM) consisting of two independent variables (frying temperature and time). The dependent variables were moisture content, oil content, colour, texture and shrinkage. The cocoyam tubers were cut into uniform slice of 3 mm thickness and fried at different temperature (150 – 190 oC) and time (5 – 9 minutes). Frying conditions significantly influenced all dependent variables at p<0.05. Coefficients of determination (R2) of the models ranged from 0.891 to 0.998 which indicated that the variables were adequately fitted to the regression equation and could highly predict the quality attributes of deep fried cocoyam chips. The optimum conditions were frying temperature of 190 oC and frying time of 7.59 minutes. This gave 7.85% moisture content, 11.59% oil content, 63.81 colour, 5.32 N crispness and 13.14% shrinkage. 
HISTOGRAM NORMALIZATION TECHNIQUE FOR PREPROCESSING OF DIGITAL MAMMOGRAPHIC IMAGES
Get PDFDigital mammogram has become the most efficient tool for early breast cancer detection modalities and pre-processing these images requires high computational capabilities. Pre-processing is one of the most important step in the mammogram analysis due to poor captured mammographic image qualities. Pre-processing is basically used to correct and adjust the mammogram image for further study and classification. Many image pre-processing techniques have been developed over the past decades to help radiologists in diagnosing breast cancer. Most studies conducted have proven that a pre-processed image is easier for radiologist to accurately detect breast cancer especially for dense breast. Different types of techniques are available for pre-processing of mammograms, which are used to improve image quality, remove noise, adjust contrast, enhance the image and preserve the edges within the image. This paper acquired 20 digital mammograms from Mammographic Image Analysis Society (MIAS) database and uses Histogram Normalization algorithm for pre-processing of the mammograms. A percentage of 95% was obtained. It was observed that the pre-processed mammographic images displayed breast abnormalities clearer with little or no noise
INVESTIGATION OF SOFTWOOD ASH,HARD WOOD ASH AND RICE HUSK ASH AS A PARTIAL REPLACEMENT OF ORDINARY PORTLAND CEMENT IN CONCRETE
Get PDFCement is known globally to be the most expensive constituents of concrete. During its course of production, the CO2 which is released has negative impacts both on human’s health and other inhabitants in the community. These problems however have called for sourcing suitable and effective waste products as an alternative to cement in concrete. Hard wood ash(HWA), Soft wood ash (SWA) and Rice husk ash(RHA)were investigated experimentally to know their suitability as cementitous materials partially replaced for cement in concrete. The calcination was done under controlled temperature 450 ºC andSWA,HWA and RHA were found to belong to class N pozzolaniccementitous materials. The design concrete mixed was 1:2:4 at water cement ratio 0.6, and 0%. 5%, 10%, 15% and 20%percentage replacement were used. The results revealed a general trend of decrease in compressive strength of the concrete as percentage replacement with SWA, HWA and RHA increased but increased as curing age of concrete increased from 5% to 20%. All the samples had highest compressive strength at 5% replacement with 19.3N/mm2, 19.1N/mm2and 16.3N/mm2 for SWA, HWA and RHA respectively at curing age 28 day while the lowest values were observed when percentage replacement was 20% with 12.7N/mm2, 12.5N/mm2 and 9.7 N/mm2 at the curing age 28 day for HWA, SWA and RHA accordingly.The type of used was found to have played major role in affecting the compressive strength and other parameters obtained for the concrete produced. However, 5% percentage replacement with the highest compressive strength at the curing age 28 day and the lowest water absorption values were observed to be the most suitable. The SWAwas therefore found to be the most suitable cementituous material followed by HWA and RHA was the least
MONTE CARLO SIMULATIONS FOR UNCERTAINTY QUANTIFICATION: MATHEMATICAL FOUNDATION AND IMPLICATION OF UNDERLYING ASSUMPTIONS
Get PDFMany problems in petroleum engineering involve solving multivariable complex integrals and analytic calculation is rarely possible in most practical cases. Numerical approximation appears to be practicable. However, majority of existing numerical solution of a D–dimensional integral with a relative accuracy (?) requires a computation time proportional to ?-D. Hence, the use of Ordinary Monte Carlo simulation (OMCS) in uncertainty quantification has gained tremendous attention. In reality, when historical data is available, variables are not independent and identically distributed (iid). The direct sampling of variable under this condition is not expected to be easy and use of OMCS can be erroneous. Methods based on Markov Chains will offer reasonable solution to this problem. This study evaluates simulation methods for quantifying uncertainty in reservoir forecast. The implications of underlying mathematics and assumptions that characterizes them were covered. The p5-p10–p50–p90-p95 uncertainty envelopes from different methods were presented using a case study from Niger Delta. The result is useful for identification and selection of effective tools in uncertainty quantification in the oil industry
OPTIMIZATION STUDIES OF TURBIDITY REMOVAL IN ASA RIVER WATER USING CARICA PAPAYA SEEDS AS COAGULANT
Get PDFThis study evaluated the potential of Carica papaya Seed (CPS) as a coagulant for water treatment. Surface water samples from Asa River in Ilorin, Kwara State, Nigeria were collected for the study. The trace metal levels were determined using Inductively Coupled Plasma-Mass Spectroscopy (ICP- MS) . Treated CPS was obtained from its seed using soxhlet extraction in ethanol .It was then applied for the removal of turbidity and trace metals in the surface water samples. The trace metal results showed the presence of Cu (6.07 ppb), Fe(394.16 ppb), Cr(21.50 ppm), Zn (6.69 ppb) and Ti (13.08 ppb) in the samples of the river water. Optimization studies was carried out for turbidity removal using Full Central Composite Design (FCCD) under the Response Surface Methodology (RSM). The results obtained showed that the maximum turbidity removal of 94.92% was achieved at optimum conditions; coagulant dose (0.47 g), contact time (15.17 min) and agitation speed (791.33 rpm). Also, all the trace metals were found to be below detection limit after contacting with the modified Carica papaya seed
ANALYSES OF COPPER CONCENTRATIONS IN PALM KERNEL CAKE FROM THREE INDUSTRIAL PALM KERNEL OIL MILLS.
Get PDFPalm kernel cake, a by-product of palm kernel seed oil processing was analysed for its metallic contamination as livestock feed without modification or Zinc supplementation. Metalloid analysis of cake from industrial output revealed Copper II ion (Cu2+) concentration in quantities dangerous to livestock. Samples of Palm kernel cake, De-oxidised cake and Palm kernel oil products from industrial lines were analysed to determine sources of contamination in the cake using flame photometry, flame emission spectroscopy and Atomic Absorption Spectrometry. The sources of contamination were traced to the feed quality, materials of construction of the expeller section and degree of purification of bye-product and waste discharged. Preliminary investigation in fresh fruit showed that copper was a component, in the range of 14.43±0.4 and 17.03±0.6 (µg/g) but higher copper content was later found associated with by–products at higher concentrations along the process lines, especially at the crushing and solvent extraction stages. To take care of high copper concentrations and obtain less contaminated cake from industrial practices with a good inventory mechanism with free and dried kernel with concerns to the materials of construction to enhance continuous usage of cake as livestock feed supplement was proposed
RICINUS CUMMUNIS AS FEEDSTOCK FOR RAW VEGETABLE OIL EXPRESSION VIA MECHANICAL EXTRACTION PROCESS: OPTIMIZATION STUDY
Get PDFCrude castor oil (CCO) extracted by Mechanical extraction process (MEP) using mechanical screw press has attracted much attention and widely recognized as one of the useful methods of expressing oil from any feedstock. Therefore, in this study, the use of Ricinus Cummunis as feedstock to produce raw vegetable oil is studied. This study was performed using design of experiment (DOE), emphasis is on response surface methodology (RSM) based on three independent variables at five levels of central composite design (CCD) with ? = 2. The extraction process variables are reaction temperature (40-200 oC), force (550-750 kN) and mass (20-100 g). Interactions between the variables were found to possess’ significant effect on the yield of crude castor oil. However, a coefficient of determination (R2) value of 0.99 shows the fitness of a second-order model for this study. The mathematical model developed is found to be adequate to describe the experimental parameters range and also provide a statistically accurate prediction of the optimum expression of oil yield. At 199.45 oC reaction temperature, 745.38 kN force and mass of 99.88 g, an optimum crude oil yield of 31.01% at 0.9 efficiency model prediction was obtained, which means mechanical extraction process has the ability as a cost effective process to express oil from any feedstock containing oil