6 research outputs found

    Characterization of Catalytic Porous Medium Using Platinum for Micro-combustion Application

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    In this study, catalytic alumina porous medium has been fabricated by using platinum as an active material for micro-combustion application. Platinum has been deposited onto porous medium surface via wet impregnation method. The porous medium undergoes surface modification process via wash coating method using gamma alumina (γ-Al2O3) solution, before being impregnated with platinum in order to increase the surface area. The surface morphology of porous medium entirely changes from smooth “solid-rock” into rough “sand-like” after the wash coating process. The amount of platinum deposited onto the treated porous medium is 1.66 wt.%. LPG combustion analysis shows that the combustion is successfully occur inside the catalytic porous media with overall efficiency of 71%

    CFD Simulation of Air-Piloted Downdraft Gasification Process: A Comparative Study Between Coal and Palm Kernel Shell as Feedstock

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    A fixed bed downdraft gasifier model based on computational fluid dynamic (CFD) framework was developed to investigate the influence of feedstock (palm kernel shell [PKS] and coal) on the quality of syngas produced via the gasification process. Euler–Euler approach was utilized in this study to describe the gas and solid phases. Realizable k-ε turbulence model was used to evaluate the constitutive properties of the dispersed phase and the gas phase behavior. This simulation model was validated by comparing the syngas composition of gasification simulation of coal with previous research, which yielded the overall accuracy result of 83.2%. This study also highlighted that PKS gasification produced 53.74% and 90.51% higher composition of H2 and CO respectively as compared to coal gasification. Whereas coal gasification produced 81.35%, 71.31% and 52.29% higher composition of CH4, H2O and CO2 respectively as compared to PKS gasification. Hence, PKS produced 66.2% higher combustible gas of H2 and CO than coal. PKS is thus considered as a potential renewable feedstock for gasification process as an alternative to the non-renewable coal. In addition, PKS gasification produced 52.29% lesser composition of CO2 as compared to coal gasification

    CFD Simulation of Air-Piloted Downdraft Gasification Process: A Comparative Study Between Coal and Palm Kernel Shell as Feedstock

    Get PDF
    A fixed bed downdraft gasifier model based on computational fluid dynamic (CFD) framework was developed to investigate the influence of feedstock (palm kernel shell [PKS] and coal) on the quality of syngas produced via the gasification process. Euler–Euler approach was utilized in this study to describe the gas and solid phases. Realizable k-ε turbulence model was used to evaluate the constitutive properties of the dispersed phase and the gas phase behavior. This simulation model was validated by comparing the syngas composition of gasification simulation of coal with previous research, which yielded the overall accuracy result of 83.2%. This study also highlighted that PKS gasification produced 53.74% and 90.51% higher composition of H2 and CO respectively as compared to coal gasification. Whereas coal gasification produced 81.35%, 71.31% and 52.29% higher composition of CH4, H2O and CO2 respectively as compared to PKS gasification. Hence, PKS produced 66.2% higher combustible gas of H2 and CO than coal. PKS is thus considered as a potential renewable feedstock for gasification process as an alternative to the non-renewable coal. In addition, PKS gasification produced 52.29% lesser composition of CO2 as compared to coal gasification

    Prediction model of hand arm vibration exposure among hand-held grass-cutters in Malaysia

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    Prolonged exposures to hand-transmitted vibrations from grass-cutting machines have been associated with increasing occurrences of signs of occupational diseases related to the hand-arm vibration syndrome (HAVS). However, there are no specific processes available that cover the objective and subjective health cause-effects of the hand arm vibration risk factors during onsite operations. Most of the existing vibration control measures have not extensively integrated administration and engineering techniques to be utilized as health prediction screening models. Therefore, the main objectives of this study are to integrate the engineering and administration control approach for reducing HAVS among hand-held grass-cutting workers and to determine the significant correlation of the objective and subjective measurement variables of the Hand Arm Vibration Exposure Risk Assessment (HAVERA) on hand arm vibration symptoms and disorders. The study was conducted in two stages: evaluation of the HAVERA variables (Stage 1) and development of the health prediction cause-effect model of the HAVERA process using multiple linear regressions and feed forward neural network programming (Stage 2). For the onsite measurement, the daily vibration value depicted an exceeded exposure action value of 2.5 m/s2 for both hands; and experiences of any finger colour change were claimed by 80% of the 204 subjects. This shows that the HAVERA process provided a good indication of HAVS which are reported as vascular, neurological and musculoskeletal disorders. In the right and left hand prediction model development, the results of the neural network model demonstrated a higher reliability performance as compared to the linear model for hand grip strength and hand numerical scoring assessment. The prediction of the HAVERA model using the neural network method has been developed for monitoring health conditions due to hand-transmitted vibrations among hand-held grass-cutting workers in Malaysia

    Study on temperature uniformity of thermal spreader integration with microcombustor for thermoelectric power generator

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    The effect of material, thickness and the magnitude of heat generated by microcombustor on heat distribution along thermal spreader for thermoelectric power generator are investigated. Impact of various materials and physical properties was studied upon sample 3 cm × 3 cm. The effect of thermal conductivity, specific heat capacity and thickness towards temperature uniformity of thermal spreader is observed. The result provides temperature profile of the thermal spreader dependencies of the source of heat. Results show that copper is the best thermal spreader material for thermoelectric power generator

    Countrywide survey on ISO 9001-certified companies in Malaysian construction industry

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    This article reports part of the results collected from 100 ISO 9001-certified companies in the Malaysian construction industry for a PhD research. Construction industry has bad public image because of safety, delay and quality issues. This is due to extreme segmentation and fragmentation of the supply chain, which cause difficulties in managing quality in construction industry. Due to low quality and low productivity, there is a need to implement ISO 9001 quality management system. This article helps to address the lack of data and information identified by CIDB Malaysia by documenting the extent to which Malaysian construction companies are accredited with ISO 9001 certifications, summarising the motivations behind the pursuit for ISO 9001 certifications, investigating the reasons for firms to obtain and maintain ISO 9001 certifications status in their organisations, and reviewing the extent to which ISO 9001-certified companies have gained benefits through the implementation of ISO 9001 quality management system. The results reveal that companies in the Malaysian construction industry adopt ISO 9001 certifications mainly to enhance their competitive processes and competitive performance to enable them to operate more efficiently
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