Papers by nwankwojike nduka
International journal of mechanical and production engineering research and development, 2020
A simulation model for producing different types/qualities of ceramic tiles from ohiya clay-felds... more A simulation model for producing different types/qualities of ceramic tiles from ohiya clay-feldspar-quartztalc-pyrophyllite mix was developed in this study to advance industrial scale utilization of abundant natural clay reserve at Ohiya in Abia State of Nigeria. This clay mineral remained stranded in the hands of local artisans and small scale investors due to associated defects in most ceramics produced from it using existing/foreign formulations. The effects of varied formulations of ohiya clay, feldspar, quartz, talc and pyrophyllite on the linear shrinkage, modulus of rupture, water absorption, apparent porosity and bulk density of their associated tiles were empirically assessed and simulated using response surface based desirability analysis. The developed simulation predicts optimal settings of these materials for producing any desired tile. Experimental results revealed the simulation's prediction accuracy of over 99% and 47:24:3:20:6 as optimal mix of ohiya clay, feldspar, pyrophyllite, talc and quartz for standard floor tiles production. The respective linear shrinkage, modulus of rupture, water absorption, apparent porosity and bulk density of 8.08%, 52.59kg/cm3, 2.48%, 5.01% and 2.09g/cm 3 exhibited by tiles developed using this product design conformed to ISO/NIS set standards. Production of standard floor tiles of 0.0929m 2 with this optimal formulation yielded zero defect and 4.64% savings. Hence, adoption of the developed simulation for producing any desired type/quality of ceramic tile from ohiya clay is recommended
The influences of the driving power, P cake breaker speed, c N auger speed, a N and helix angle, ... more The influences of the driving power, P cake breaker speed, c N auger speed, a N and helix angle, of a palm nut-pulp separating machine on its
International Review of Mechanical Engineering-IREME, Feb 28, 2019
An integrated machine has been designed and developed to aid mass production of unparboiled roast... more An integrated machine has been designed and developed to aid mass production of unparboiled roasted breadfruit kernel in order to avert persistent scarcity of this unique nutritious snack. The machine was fabricated using local sourced standard materials with electric motor, roaster, dehuller, blower, kernel and shell discharging chutes as its major components. Performance analysis revealed that this system eliminated human contact with the breadfruit nuts during processing while 0.74kg/h, 93.63% and 167.93kJ/kg constitute its throughput, efficiency and specific energy consumption respectively. Thus, adoption of this innovation is recommended as a veritable option for quality roasted breadfruit kernel production since it reduced drudgery and improved hygiene.
Journal of Emerging Trends in Engineering and Applied Sciences, 2012
A palm nut-pulp separator consisting of a cake breaker, auger separator, hopper, 3HP electric mot... more A palm nut-pulp separator consisting of a cake breaker, auger separator, hopper, 3HP electric motor, nut and pulp discharging chutes was designed, fabricated and evaluated. The results of its performance test indicated 90.05% and 419.92kg/h as the efficiency and throughput of the separator respectively. The results of the comparative analysis of introducing this machine in semi-mechanized small scale palm fruit processing showed significant differences in the amount of palm oil extracted and palm oil loss to pressed fibre in the existing semi-mechanized methods and this new technique. Also the results indicated no significant difference (at α = 0.05) in the oil loss to palm nuts between the two processes irrespective of the type of fruit processed. The average quantity of palm oil extracted is greater while oil loss to fibre is low when the mechanized process with palm nut-pulp separation was used and also this new technique eliminated nut breakage and second pressing operation. All materials used for fabrication were sourced locally, and the estimated cost of producing this machine is one hundred and twenty seven thousand, one hundred and sixty naira (₦127,160.00).
Journal of Emerging Trends in Engineering and Applied Sciences, 2012
This paper assessed the benefits of introducing a palm nut-pulp separating machine in the small s... more This paper assessed the benefits of introducing a palm nut-pulp separating machine in the small scale palm fruit processing. The parameters evaluated and compared between the new semi-mechanized palm fruit processing method with the nut–pulp separation step and the existing semi-mechanized method include the FFA content of palm oil extracted, processing time, cost of production and revenue/profit yield. The results showed no significant difference (at α = 0.05) in the FFA contents of palm oils extracted from the same variety and quality of fruit in the two methods. Also the time and cost of processing 900kg of palm fruits were reduced from 227.40 seconds to 170.40 seconds and from ₦6750.00 (≈$42.19) to ₦5250.00 (≈$32.81) with the introduction of the palm nut-pulp separating machine. In addition, results further revealed that the new mechanized method with palm nut-pulp separation step yielded average revenues of ₦23.53 (≈$0.15) and ₦37.53 (≈$0.24) per unit mass of dura and tenera fruits processed respectively while the existing technique yielded ₦16.74 (≈$0.11) and ₦27.78 (≈$0.17) respectively. The summary of the costs and revenue involved showed that the semi-mechanized method with nut-pulp separation step yielded a profit of ₦7611.00 (≈$47.57) and ₦9807.00 (≈$61.30) over the existing method when an optimal throughput (900kg) of dura and tenera fruits were processed respectively.
Proceedings of the International Conference on Industrial Engineering and Operations Management
Journal of Vibration Engineering & Technologies
Frontiers in Energy, 2014
In this paper, the end-use efficiencies of the different energy carriers and the overall energy e... more In this paper, the end-use efficiencies of the different energy carriers and the overall energy efficiency in the Nigerian residential sector (NRS) were estimated using energy and exergy analysis. The energy and exergy flows were considered from 2006 to 2011. The overall energy efficiency ranges from 19.15% in 2006 to 20.19% in 2011 with a mean of (19.96±0.23)% while the overall exergy efficiency ranges from 4.34% in 2006 to 4.40% in 2011 with a mean of (4.31±0.059)%. The energy and exergy efficiency margin was 15.58% with a marginal improvement of 0.07% and 0.02%, respectively when compared with previous results. The contribution of the energy carriers to the total energy and exergy inputs were 1.45% and 1.43% for electricity, 1.95% and 3% for fossil fuel and 96.6% and 95.57% for bio-fuel. The result shows that approximately 65% of the residence use wood and biomass for domestic cooking and heating, and only a fraction of the residence have access to electricity. LPG was found to be the most efficient while kerosene, charcoal, wood and other biomass the least in this order. Electricity utilization exergy efficiency is affected by vaporcompression air conditioning application apart from low potential energy applications. In addition, this paper has suggested alternatives in the end-use application and has demonstrated the relevance of exergy analysis in enhancing sustainable energy policies and management and improved integration techniques.
West African Journal of Industrial and Academic Research, 2013
A water pipeline network analysis with a case study of Owerri in Imo State, Nigeria municipal wat... more A water pipeline network analysis with a case study of Owerri in Imo State, Nigeria municipal water reticulated system has been undertaken. What prompted this study is that the case study has a lot of fluctuations in its head loss. Also, the discharge is not proportional to the pipe diameter. The study therefore adopted simultaneous loop flow correction method because it computes simultaneous flows corrections for all loops, hence, the best since computational procedures takes into account the iterative influence of flow corrections between loops which have common pipes. After applying the simultaneous loop flow correction analyzer in a twenty-four sampled pipeline network, a drastic reduction in head loss and regular line along the axis was observed. Besides, the rate at which the water flows was observed to be proportional to the pipe diameter. Hence, the method is a useful aid in planning, designing and operating of reticulated pipeline network for higher efficiency and improved ...
West African Journal of Industrial and Academic Research, 2013
A water pipeline network analysis with a case study of Owerri in Imo State, Nigeria municipal wat... more A water pipeline network analysis with a case study of Owerri in Imo State, Nigeria municipal water reticulated system has been undertaken. What prompted this study is that the case study has a lot of fluctuations in its head loss. Also, the discharge is not proportional to the pipe diameter. The study therefore adopted simultaneous loop flow correction method because it computes simultaneous flows corrections for all loops, hence, the best since computational procedures takes into account the iterative influence of flow corrections between loops which have common pipes. After applying the simultaneous loop flow correction analyzer in a twenty-four sampled pipeline network, a drastic reduction in head loss and regular line along the axis was observed. Besides, the rate at which the water flows was observed to be proportional to the pipe diameter. Hence, the method is a useful aid in planning, designing and operating of reticulated pipeline network for higher efficiency and improved ...
Industrial Engineering Letters, 2018
The key goal of predicting the state expectation of an engineering system is to predict the remai... more The key goal of predicting the state expectation of an engineering system is to predict the remaining life of the system so as to aid in maintenance decision-making activities. In this paper, a maintenance model for predicting the state expectation of industrial machines has been developed. It incorporates various stages of deterioration and maintenance states. Given that a current state has been attained, from inspection and diagnosis, this model is capable of computing the predicted average time before a system failure occurs. This study focuses on using real data of an industrial Bottle filler machine to test the effectiveness of the State Expectation model and its effect on the reliability and maintainability of the machine. The model is tested for various scenarios by changing one of the main parameters during each calculation while others are kept constant. For the state duration sensitivity analysis, as the failure rate continuously increases from 0.0178 to 0.7060, the expect...
Industrial Engineering Letters, 2018
Equipment Condition Management used for predicting the performance parameters required for mainte... more Equipment Condition Management used for predicting the performance parameters required for maintenance decision making was developed. This program predicts the state probabilities and maintenance action recommendation based the predetermined alert levels. The maintenance program software was developed from the derived stable state probability models using algebraic substitution and computation of the breakdown data and operational data of the MTTF, MTTR, λ and µ of these equipment/component(s) at PM and CM states with implementation algorithm. The models were derived using mechanistic modeling technique such that all the relevant variables of the reliability process were accounted for. Validation analysis of this simulation revealed its prediction accuracy of over 99%. Therefore, its use in the monitoring and evaluation of the health conditions of production systems remains very essential. Keywords: Mechanistic model, process parameter, stable state probabilities, prediction algorit...
International Review of Mechanical Engineering-IREME, Jul 31, 2013
An integrated digester-separator-screw press machine for digesting sterilized palm fruit, separat... more An integrated digester-separator-screw press machine for digesting sterilized palm fruit, separating the digested mash into nuts and pulp before pressing only the digested pulp for palm oil extraction was developed and evaluated. This machine, designed based on the modified palm oil and nut extraction process and fabricated using locally sourced standard materials, eliminated drudgery in the loading and discharging of intermediate materials among the digestion, nut-pulp separation and pressing operations in the new process. The major components of this machine include an electric motor, feed hopper, horizontal digesting unit, cake breaking unit, auger separating unit, screw press and discharging outlets for palm nut, palm oil and pressed fibre. Performance test analysis revealed nut breakage index, average throughput and palm oil extraction efficiency of this machine as zero, 204.51kg/h and 97.44% respectively. Thus, the integrated machine constitutes a veritable option for quality palm oil and nuts production boost in small and medium scale palm fruit processing.
Industrial Engineering Letters, 2015
Separator Optimuz used for predicting the optimal operational parameters required for replicating... more Separator Optimuz used for predicting the optimal operational parameters required for replicating (manufacturing) palm nut-pulp separating machine with different capacities in line with the varying scales/budgets of oil palm fruit processors was developed. This program also predicts the throughput, energy consumption and operation time expected of this machine when fabricated with a given set of operational parameters. The Separator Optimuz was developed from the derived throughput (TP) and energy consumption (SE) models of the separator using algebraic substitution/computation and non-linear programming algorithms in which the SE is minimized subject to the constraints of any desired TP value and limits of the machine parameters. The models were derived using mechanistic modeling technique such that all the relevant variables of the machine as well as properties of the processed materials (digested palm fruit mash, palm nut and pulp) were accounted for. Comparative analysis of this software predictions and experimental results revealed over 99% prediction accuracy. In addition, with the Separator Optimuz the specific energy consumption, cake breaker and auger speeds of a 900kg/h machine reduced from 16.41kJ/kg, 2821rpm and 2116rpm respectively of response surface optimization to 80.95J/kg and 733.13rpm for both speeds. Thus, the energy saving potentials and stability of this machine improved with this application. Separator Optimuz is therefore recommended for predicting optimal operational parameters of palm nut-pulp separator before manufacture to ensure efficient operation and low cost of quality palm oil and nut production. Key Words: Mechanistic model, optimal operational parameter, palm nut-pulp separator, prediction, Separator Optimuz
International Journal of Thermofluids
Network analysis technique was used in this study to establish the optimal duration and labour co... more Network analysis technique was used in this study to establish the optimal duration and labour cost of overhauling ABB type 13D gas turbine in Nigeria as well as the critical jobs that required adequate management attention/supervision in order to check corrupt upward review of project cost that characterized this sector resulting from intentional delays in the execution of turbine overhauling projects in this country. Results showed one thousand, two hundred and forty- three (1243) hours or approximately 155.38 days (at 8 working hours per day) and four million, twelve thousand and five hundred
This paper assessed the benefits of introducing a palm nut-pulp separating machine in the small s... more This paper assessed the benefits of introducing a palm nut-pulp separating machine in the small scale palm fruit processing. The parameters evaluated and compared between the new semi-mechanized palm fruit processing method with the nut–pulp separation step and the existing semi-mechanized method include the FFA content of palm oil extracted, processing time, cost of production and revenue/profit yield. The results showed no significant difference (at α = 0.05) in the FFA contents of palm oils extracted from the same variety and quality of fruit in the two methods. Also the time and cost of processing 900kg of palm fruits were reduced from 227.40 seconds to 170.40 seconds and from N6750.00 (≈$42.19) to N5250.00 (≈$32.81) with the introduction of the palm nut-pulp separating machine. In addition, results further revealed that the new mechanized method with palm nut-pulp separation step yielded average revenues of N23.53 (≈$0.15) and N37.53 (≈$0.24) per unit mass of dura and tenera fr...
A palm nut-pulp separator consisting of a cake breaker, auger separator, hopper, 3HP electric mot... more A palm nut-pulp separator consisting of a cake breaker, auger separator, hopper, 3HP electric motor, nut and pulp discharging chutes was designed, fabricated and evaluated. The results of its performance test indicated 90.05 % and 419.92kg/h as the efficiency and throughput of the separator respectively. The results of the comparative analysis of introducing this machine in semi-mechanized small scale palm fruit processing showed significant differences in the amount of palm oil extracted and palm oil loss to pressed fibre in the existing semimechanized methods and this new technique. Also the results indicated no significant difference (at α = 0.05) in the oil loss to palm nuts between the two processes irrespective of the type of fruit processed. The average quantity of palm oil extracted is greater while oil loss to fibre is low when the mechanized process with palm nut-pulp separation was used and also this new technique eliminated nut breakage and second pressing operation. All...
This study used Linear Programming technique to determine the ratio of dura to tenera palm fruits... more This study used Linear Programming technique to determine the ratio of dura to tenera palm fruits required for optimal performance of oil palm sector and other sectors that depends on it. The investigation was based on a latest modified mechanical palm fruit processing method involving separation of digested fruit mash into palm nut and pulp before pressing of the digested pulp for palm oil extraction. Contrary to the general view that tenera production is best for commercial purpose, this optimization result revealed 23:20 as the optimal dura/tenera ratio required in this sector. The result also indicated a profit of $0.41 from processing of dura and tenera palm fruits in this ratio over processing of the same quantity (1000kg fresh fruit) of tenera alone. In addition to this profits improvement, implementation of this fruit production ratio in this sector will also raise the availability of palm kernel oil and cake to rally with their ever increasing industrial applications withou...
Optimal products design for producing standard ceramic porcelain products from Ohiya clay was det... more Optimal products design for producing standard ceramic porcelain products from Ohiya clay was determined in this study using desirability function analysis. Results revealed that the alumino-silicate constitutes 91% of the total mineralogical composition of Ohiya clay and 42:32:20 at a firing temperature of 1250/1300 oC; 42:33:17 at a firing temperature of 1300 oC; 41:32:27 at a firing temperature of 1000 oC as the optimal mix of the clay, feldspar and silica for producing standard low/high voltage insulators, tiles and tablewares respectively. The production of the 11 kV electric insulator, 400 × 400 mm tile, serving dish at optimal settings are respectively six hundred and twenty-five naira (₦625), three hundred and twenty-two naira (₦322), three hundred and four seven (₦347) against the market prices of one thousand naira (₦1000), three hundred and fifty naira (₦350), four hundred and twenty naira (₦420) respectively. This translates to 60%, 9% and 21% in profit for these product...
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Papers by nwankwojike nduka