bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of an occupational risk using injury safety indicators
Authors: Rumyantseva N , Primak E , Uljanov A , Kiss V
Published: December 2019

An analytical data mining approach to the assessment of an occupational risks is proposed and based on the use of an injury safety indicator, which allows to determine the degree of safety (hazard) of the workplace, to carry out statistical processing of the results collected with its help, which will help with further planning of labour protection measures. The results of an occupational risk assessment with the use of an injury safety indicator make it possible to predict the levels of occupational risks at various workplaces, which makes it possible to develop the optimal management decisions for the preservation of the life and health of workers in enterprises. The prospect of using data mining methods in the tasks of labour protection management at an enterprise opens up the possibility of creating decision-making mechanisms that take into account the dynamic state of the working environment and make it possible to increase the validity of the choice of priority labour protection measures.
Effect of coatings on the sprinkler deflector
Authors: Balabanov I , Tanklevskiy A , Yusupdzhanov V , Babikov I , Arakcheev A
Published: December 2019

One of the most important tasks in the construction and maintenance of buildings and compartments is to ensure fire safety of the premises. In general, the most reliable, effective and cost-effective way to ensure fire safety is the introduction of automatic fire extinguishing systems (afes), in particular water-based, which effectively protect people and property. This article will present the results on the selection of the deflector of the sprinkler for certification in the center of fm global, and considered the influence of the coating on the deflector of the sprinkler.
Determination method of sprinklers with electrical activation in case of internal fire
Authors: Babikov I , Tanklevskiy A , Arakcheev A , Tarantsev A
Published: December 2019

The issues of determination of sprinklers with electrical activation of a sprinkler automatic fire extinguishing system with electrical activation in case of fire source occurring in a compartment and activation of one of the sprinklers are investigated. The problem of preventive activation of sprinklers is formulated; its solution will allow determining the minimal quantity of sprinklers and their coordinates which will ensure localization and even extinguishing using mush less water, as if activation of sprinklers was implemented in a traditional way – by heating their bulbs with ignition products. Examples are given.
Optimization of oil palm empty fruit bunch gasification temperature and steam to biomass ratio using response surface methodology
Authors: Halim N H A , Saleh S , Samad N A F A
Published: December 2019

An experimental work of empty fruit bunch gasification was conducted by using the bubbling fluidized bed to study the effect of the gasification temperature and steam biomass ratio (SBR) on the synthesis gas yield, Lower Heating Value (LHV) and Cold Gas Efficiency (CGE). Response Surface Methodology (RSM) was used to design the gasification experiment from the temperature range of 800 – 1000°C and SBR range of 0.5 – 1.5. Thirteen number of runs were generated based on Central Composite Design (CCD) with five replicated center points. Three regression models for predicting synthesis gas yield, LHV and CGE were developed and Analysis of Variance (ANOVA) was performed in this study. From ANOVA, the most influencing factor was gasification temperature which obtained higher F-value compared to SBR. The numerical optimization was also conducted in order to obtain the optimum condition to maximize the synthesis gas yield, LHV and CGE. From numerical optimization, gasification temperature of 800 °C and SBR of 1.14 were determined as the optimum condition which contributes to the maximum synthesis gas yield, LHV and CGE which are 1.25 Nm3/kg, 10.49 MJ/Nm3 and 90.72% respectively. The percentage error between the predicted and actual value of response variables was calculated and the error obtained lesser than 1%. Thus, it confirmed that the models obtained can be used to optimize the gasification of the empty fruit bunch.
Anhydrous weight loss kinetics model development for torrefied green waste
Authors: Jamin N A , Samad N A F A , Saleh S
Published: December 2019

One of the compositions of municipal solid waste (MSW) is green waste (GW) that collected from landscaping, garden, yard and trimming waste. GW has potential in becoming a biomass feedstock, but poses some drawbacks such as high moisture content, low heating value, high O/C and H/C ratios. Implementation of torrefaction as pre-treatment will improve the GW properties. During torrefaction, biomass is decomposed and leads to anhydrous weight loss (AWL). The estimation model for AWL is significant to study thermal degradation of GW. The aim of this work is to study two steps reaction in series for AWL prediction. GW were torrefied under inert condition at 240-300°C, 10°C/min heating rate and 30 minutes holding time using thermogravimetric analysis (TGA). Two steps reaction series model named Di Blasi and Lanzetta with extended non-isothermal phase is used in developing the AWL model. From initial guess, the parameters of activation energy and kinetic constant are adjusted to fit the calculated AWL to experimental AWL data by applying nonlinear optimization ‘lsqcurvefit’ routine in Matlab. The estimated kinetic parameters been used for AWL model and later being compared to experimental data from TGA. Good agreement obtained between experimental and model data indicating good kinetic parameters estimation
Integrating microwave heating pre-treatment to improve torrefaction of food waste
Authors: Ismail M , Abdul Rasid R , Abdul Rahman R N U , Ahmad N S , Mohd Radzuan M A W
Published: December 2019

The food waste (FW) disposal is one of the main issues of concern, as it affects environmental and sustainable development in Malaysia. FW should be utilized to produce more valuable products such as energy. However, FW is characterized by its low high heating value (HHV) and high moisture content and which lower the energy efficiency during energy production process. To overcome this problem, torrefaction assisted by microwave heating pretreatment is used to upgrade FW properties to produce solid biofuel which is called as biochar. The objective of this study is to investigate the feasibility of microwave (MW) heating power at 240 W for 5 min to enhance the quality of torrefied FW. The pre-treated FW is then torrefied at three different temperatures (280, 300 and 320 °C) for 30, 45 and 60 min. The torrefied FW was then characterized in terms of ultimate and proximate analysis, HHV, mass and energy yield as well as its functional groups. The optimum condition of torrefaction in this study was 320°C and 30 min with HHV of 23.82 MJ/kg, 95.54% of energy yield and 84.28% of mass yield. This suggests that torrefied FW with MW heating pre-treatment has the potential to be used as an energy source.
Aspen Plus simulation and optimization of industrial spent caustic wastewater treatment by wet oxidation method
Authors: Chandraseagar S , Abdulrazik A H , Abdulrahman S N , Abdaziz M A
Published: December 2019

Spent caustic is a waste generated by petrochemical refineries, which used to eliminate acid components such as hydrogen sulphide (H2S) and mercaptans from the refined product streams. A study was carried out on simulation and optimization of spent caustic wastewater treatment system by using Aspen Plus based on wet air oxidation (WAO) method. WAO method uses air under elevated temperature and pressure to carry out oxidation in the aqueous phase. Process flow diagram (PFD) of WAO method was drawn and relevant input data was keyed in Aspen Plus according to experimental results on WAO. Both results were validated and the results were match each another as the percentage of allowable error between both the results were less than 5 %. After that, optimization was carried out to determine the optimum ratio of spent caustic feed flow rate to air flow rate and operating temperature of the flash separator unit involved in the process. From the optimization results, it can come to a conclusion that 1: 9.2 is the minimum spent caustic feed flow rate to air flow rate ratio and optimum operating temperature of flash separator unit is 140°C in order for maximum flow rate of CH3SSCH3 in offgas stream in this simulation model of spent caustic wastewater treatment system using WAO method.
Integrating ILS in dissolving palm fruit cellulose
Authors: Mansor K N , Halim M A M , Ali N , Rahman W Z W A , Abdullah S B
Published: December 2019

Ionic liquids (ILs) are introduced to improve the production of palm oil in industry in order to extract more thus lowering the oil losses. The main objective of this study is to investigate the potential of sulfate-based ILs in dissolving palm fruit cellulose. The interpretation study was done in lab scale by dissolving cellulose (that directly extracted from palm fruit) in ILs and percentage of cellulose dissolved is calculated based on weight percentage dissolved. The highest average percentage dissolving of cellulose was 10.67 wt% with condition concentration of sulfate-based ILs is 9000 ppm and the mixing time was two hours. In a nutshell, the higher concentration of ILs and more mixing time will achieve higher percentage of cellulose dissolved.
Synthesis of optimal biogas production system from multiple sources of wastewater and organic waste
Authors: Misrol M A , Wan Alwi S R , Lim J S , Manan Z A
Published: December 2019

Biogas is one of the products that can be produced from wastewater or organic waste. Given the input streams for biogas digester can come from multiple sources rich in organic compound, optimization can be performed to maximise the production. In an industrial park with several types of industry, wastewaters and/or organic wastes from the industries or surrounding area can be used as feedstock for biogas production. Compared to conventional industrial park, Eco-Industrial Park (EIP) could be the appropriate platform for implementation as it advocates for industrial symbiosis through materials exchange and minimisation of waste, which are also in-line with the circular economy concept. In this study, a superstructure applicable for an EIP, which consists of multiple biogas sources, biogas digester, biogas upgrading, and biogas demands are developed. The model considers parameters which can affect biogas production quality and quantity such as Chemical Oxygen Demand (COD), Carbon/Nitrogen ratio (C/N ratio), and temperature. It also considers percentage of methane lost, removal efficiency of Carbon Dioxide (CO2), electricity cost, capital cost of the selected biogas digesters as well as the cleaning and upgrading units. The main objective of the mathematical model is to maximise the profit generation from biogas generation for the EIP centralized biogas production plant. The model is solved by using General Algebraic Modelling System (GAMS) software. Case study conducted shows that anaerobic closed lagoon is selected as digester for the industrial wastewaters, while water scrubber is suggested as the biogas upgrading technology. A yearly profit is estimated at USD13,700,000, which is generated from selling of 279nm3 of purified biogas. This may suggest that generating biogas from several sources of industrial wastewater and organic waste could be potentially feasible, thus reducing unnecessary pollutant while capturing the carbon source as an additional revenue stream.
Towards water integration in Eco-Industrial Park: An overview of water recovery from industries
Authors: Sa’ad S F , Zailan R , Wan Alwi S R , Lim J S , Manan Z A
Published: December 2019

Water integration among different industries in Eco-Industrial Park brings a promising opportunity in reducing freshwater consumption by implementing industrial symbiosis concept. Mixing of wastewater from industries might be cost-effective, however, it is not the best option for water reuse since different reuse option requires different water qualities and treatment. Thus, wastewater segregation based on the wastewater source and quality is required. This paper reviews the potential wastewater source from the industry and wastewater recovery prior to be reused. The review is based on the literature survey from the industries, suppliers and guidelines. From the survey, wastewater sources that can be recovered for reuse option are water generated as by-product, wastewater from the cleaning operation and utility operation. These wastewater sources cannot be mixed because each source has different types of contaminant content. Appropriate water quality can be achieved through primary, secondary and tertiary treatment. Advance technology such as membranes are efficient to remove non-desirable compounds from wastewater. The treated wastewater can provide a viable solution as an alternative water source to ease water-related stress and wastewater segregation can reduce the burden of the treatment.
Superstructure optimization of bioethanol production from corn stover
Authors: Azizan S S , Effendy N F I , Handani Z B
Published: December 2019

Bioethanol is a liquid fuel that can be produced from various raw materials. The first generation of bioethanol which are starch and sugar has begun to decline as these materials are considered to be the food sources for human as well as animals. However, the rise of production of bioethanol from the second generation which are the lignocellulosic materials has been proven to give a lot of benefits to mankind instead. Various technologies were studied in order to design an optimal processing route for bioethanol production from lignocellulosic biomass. A superstructure on the available process technologies which include the three main technologies, the pretreatment, sugar conversion, separation and purification was first developed before screening it down to a final superstructure. All of the data have been used in this study were collected from open literature and followed by the selection and development of the models required in order to solve the generic models and problems by using an optimization software, the Generic Algebraic Modelling System (GAMS). The optimization results indicate that the optimal processing route in producing bioethanol from lignocellulosic biomass include the technologies of steam explosion, dilute acid followed by fermentation, beer and dehydration of ethanol on zeolite for each process interval with maximum yield of 2238.4 kg/h.
Study of natural gas powered solid oxide fuel cell simulation and modeling
Authors: Nafees A , Abdul Rasid R
Published: December 2019

Solid oxide fuel cell (SOFC) system has been proposed to address the issue of waste gas emission due to gas flaring in oil and gas industry. System has unique advantage of consuming the waste gases and generating electricity as bye product. To analyze and quantify the proposed benefits, a robust cell performance model is highly desirable. A detailed understanding of SOFC component including electrode, electrolyte, interconnect, fuel processing and electrochemical reactions are first step in accurate determination of characteristic performance of the system. For this purpose, a review of modeling philosophies of SOFC system was undertaken in this study. Specifically, SOFC simulation and modeling using commercial software such as Aspen Plus, Aspen Hysys was focused in detail. SOFC models available in literature are either mathematical model or numerical models and ever evolving and improving. SOFC simulation rely on split approach due to absence of built-in module. Authors have developed an Aspen Hysys simulation model using split approach and discussed briefly here. Split approach approximates the SOFC phenomena, thereby inducing error. To overcome this deficiency, authors are developing a MATLAB based user model that can be integrated using ‘user unit operation’ available in Hysys. Details of the MATLAB program approach is included.
Performance modelling and validation on co-gasification of coal and sawdust pellet in research-scale downdraft reactor
Authors: Mansur F Z , Faizal C K M , Samad A F A , Atnaw S M , Sulaiman S A
Published: December 2019

Co-gasification of the fossil fuel with the biomass is considered a very promising clean energy opt-in reduce the greenhouse gas emission. The main objective of this research is to develop a simple and reliable model provided as a preliminary tool to evaluate the performance of the co-gasification of sub-bituminous coal with densified biomass (sawdust pellet, SP). The simulation model using Aspen Plus was validated with the experimental data for minimization of the Gibbs free energy model. Three performance parameter; the calorific value of the syngas (CVsyngas), syngas yield (Ysyngas) and gasification efficiency (ŋGE) were studied along with three different control parameter. The increase of the sawdust pellet blending ratio denoted in a decrease of the CVsyngas, Ysyngas and ηGE ranged from 3.00-6.00 MJ/Nm3, 1.20-2.20 Nm3/kg and 25%-37%, respectively. On the contrary, effect of the gasification temperature at the various blending ratio exhibits an increase for all the performance parameters. In addition, ERair resulted in the decline of the CVsyngas from 8.50 to 1.58 MJ/Nm3 and ηGE from 52 to 15% while vice versa for Ysyngas. Furthermore, it is found that the result obtained from the developed model agrees well with the experimental data that have been conducted in replicate.
Influenced of Ni loading on SBA-15 synthesized from oil Palm ash silica for syngas production
Authors: Razak H A , Abdullah N , Setiabudi H D , Yee C S , Ainirazali N
Published: December 2019

The nickel loading (1-3wt.%) effect on SBA-15 prepared via sol-gel method for dry reforming of methane (DRM) was investigated. Silica source of sodium silicate-oil palm ash (Na2SiO3-OPA) was obtained from extraction of OPA using mass ratio Na2SiO3/P123~2.9. The SBA-15 was synthesized via hydrothermal treatment reflux route at treatment temperature of 80 °C. A vertical stainless steel fixed-bed reactor was applied for catalytic DRM process at 800 °C, atmosphere pressure and ratio CH4:CO2 is 1:1 for 30 h. Characteristic of structure SBA-15 was successfully analyzed by TEM, indicates to the positive role of Na2SiO3-OPA as silica sources. XRD, BET and FTIR results revealed that 2Ni/SBA-15 exhibited high surface area (460.89 m2/g) and pore diameter (6.53 nm), small NiO particle (14.71 nm) which assist good metal dispersion and led to better metal-support interaction. The increase of Ni loading from 1 to 3wt.% results in lowering the surface area and pore volume of catalyst as more Ni particles tend to agglomerate and positioning on the SBA-15 pores. The performance of Ni/SBA-15 catalyst in DRM decrease with the trend of 2Ni/SBA-15>3Ni/SBA-15>1Ni/SBA-15 whereby the H2/CO followed the order of 2Ni/SBA-15≈3Ni/SBA-15>1Ni/SBA-15.These studies revealed the Ni loading influences the metal-support interaction and significantly affect the H2/CO production.
Electro-oxidation of renewable glycerol to value added chemicals over phosphorous-doped Pt/MCNTs nanoparticles
Authors: Ahmad M S , Cheng C K , Ong H R , Abdullah H , Khan M R
Published: December 2019

In the present work, Pt/MCNTs and P-dopedPt/MCNTs catalysts were synthesized via hydrothermal method and utilized for glycerol oxidation reaction (GOR). The catalysts were physio-chemically characterized by Brunauer-Emmett-Teller (BET), X-ray diffraction, field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) to investigate pore size, pore volume, structure and morphology of the catalysts. A remarkable reduction in BET surface area was found for P-dopedPt/MNCTs which 1.56 time less than the sole MNCTs is confirming the incorporation of phosphorous into the pore channels of Pt/MCNT. The TEM analysis of P-dopedPt/MCNTS demonstrated the uniform distribution of Pt nanoparticles over multiwalled carbon nanotubes with an average particle size of 6.23 nm. The activity and stability of the catalysts were analysed for GOR using cyclic voltammetry (CV) and chronoamperometry (CA). The CV testing showed the higher current density for P-doped Pt/MCNTs (28.33 A/m2) which is 2 times higher than the Pt/MCNTs (14.20 A/m2) current density. The synthesized products were analysed by high performance liquid chromatography (HPLC) analysis which demonstrated the selective synthesis of tartronic acid as a major product with maximum yield. It was found that the P-dopedPt/MCNTs have higher selectivity for tartronic acid and glyceric acid as compared to its counterpart.
Characterization of a novel terpolymer containing maleic anhydride-co-stearyl methacrylate-co-benhely acrylate for wax inhibition application
Authors: Elganidi I , Elarbe B S , Abdullah N , Ridzuan N
Published: December 2019

Wax deposition in petroleum pipelines is deliberated as one of the most severe operational issues, and extraordinary efforts have been made to remediate and prevent this flow assurance problem. Using, polymeric pour point depressants (PPD) as a wax control strategy to improve the fluidity of waxy crude oil and reduce the pour point have received significant attention. The purpose of the current research is to synthesize novel terpolymers which used as PPD and viscosity improvers. The synthesis process occurred via polymerization of stearyl methacrylate (SMA), benhely acrylate (BA), and maleic anhydride (MA) monomers using free radical polymerization method in toluene as a solvent, and (1 wt%) benzoyl peroxide (BZP) as initiator. The chemical structure of the prepared terpolymer was characterized by FTIR and NMR. Also, the crystallization behavior of paraffin wax was investigated by differential scanning calorimetry (DSC). Experimental investigations furnish that the synthesized PPD showed high yield (87%) at the concentration (1:1:1) of BA-co-SMA-co-MA. From FTIR and 1HNMR characterization results observed that maleic anhydride moiety, alkyl chain moiety, and methacrylate moiety are existing in the prepared terpolymer. Furthermore, DSC analysis showed that the glass transition temperature of the prepared terpolymer is weakly stated over a wide temperature range.
Characterization of dehydrated keratin protein extracted from chicken feather
Authors: Alashwal B Y , Gupta A , Husain M S B
Published: December 2019

Keratin is one of the most important biomaterials due to its relatively good biocompatibility, high physicochemical with excellent mechanical properties and good film coordination ability. Chicken feathers are a major waste in poultry industries however, 90% of pure keratin can be obtained from the total featherweight. Chicken feathers are abundant of keratin protein which can be considered as a suitable protein source and used as a component in the cosmetic and pharmaceutical industry. The aim of this study is to extract keratin protein from chicken feather source. The chemical structure of the keratin protein was examined by Fourier transform infrared spectroscopy (FTIR). The results showed the presence of, Amide I-III bands, which gave critical information on the protein conformation and alteration in backbone structure of the keratin., Surface morphology analysis was described by Scanning electron microscopy (SEM). The extracted keratin was found to present aspheric shaped, small microspheres with smooth surface. Meanwhile the X-Ray Diffraction results showed the crystalline form of the chicken feather dehydrated keratin. The diffraction peak was indexed for the β-sheet crystalline structure of keratin. In conclusion, the characterization of keratin extracted from chicken feathers was successfully performed using the abovementioned analyses.
Properties of microcrystalline cellulose prepared from oil palm empty fruit bunch at different sulfuric acid concentration and hydrolysis temperature
Authors: Sukaimi J , Wan Abdullah W N H , Supian M A F , Jamari S S , Mohd Azman N A , Mohamad S , Ali M F
Published: December 2019

Microcrystalline cellulose (MCC) is a biodegradable crystalline powder that normally isolated through acid hydrolysis process of cellulose. However, the implication of high concentration of acid, such as more than 5M sulfuric acid (H2SO4) in MCC production is concerned. Therefore, this work studies the effect of low acid concentration (1.5, 2.5 and 3.5 M) and hydrolysis temperature (40, 60 and 80 °C) for the MCC isolation from oil palm empty fruit bunch (EFB) assisted with steam explosion process cellulose fibers. Yield, crystallinity and chemical properties of the isolated EFB-MCC were discussed and compared with the commercial MCC. The crystallinity result shows the range of 72 – 77% for the isolated EFB-MCC. The highest crystallinity (77%) achieved at 3.5M H2SO4 at 80°C, similar to the crystallinity of the commercial MCC. As for the yield, the trend is decreasing severely as the increment of temperature, however small reduction of yield detected at different H2SO4 concentration. While for the chemical properties, FTIR spectra illustrated consistent wavenumbers detection for the EFB-MCC, commercial MCC and exploded EFB-Cellulose. It can be concluded that the optimum condition for the acid hydrolysis process is 1.5M H2SO4 at 60 °C with the middle range of crystallinity (74.7 %) and yield (82.4 %).
Three different types of tea as surfactant in liquid exfoliation of graphite: green tea, black tea and oolong tea
Authors: Ismail F S , Yusoh K , Zainal Abidin A S , Abdullah A H , Ismail Z
Published: December 2019

Liquid phase exfoliation (LPE) with surfactant-assisted is a method to produce graphene that used water and surfactant as solvent. Tea is one of possible surfactants that can be used in LPE of graphite as it reduced the surface tension energy of water (72.75 mJ m−2) to ~40 – 50 mJ m−2which is suitable level to exfoliate graphite. Three different types of tea were used as surfactant through one-step production of graphene which were green tea (GT), black tea (BT) and oolong tea (OT). The exfoliation of graphite in each tea solutions were successful as the UV spectra of supernatant samples show peak at 270 nm which indicates the C – C bond of graphene flakes. Morphology analysis (AFM) of resulted graphene samples show that graphene sheets have sharp edges caused by sonication process. The effect of sonication time was being investigated in this work. Green tea has higher exponent factor of time (1.715) compare to black tea (1.033) and oolong tea (0.762) due to high quantity of small molecules of polyphenols present in green tea solution. Thus, it is better to used GT as surfactant in LPE of graphite compare to BT and OT.
Synthesis of alumina from aluminium can waste to be applied as catalyst support for biodiesel production
Authors: Bin Mokaizh A A , Wirman N , Shariffuddin J H
Published: December 2019

Abundant of aluminum beverage cans are normally discarded after use have caused considerable land pollution and environmental problems. This research is therefore aimed to synthesize alumina from aluminum can waste which is one of the most common kind of waste. The objective of this research is to synthesize and characterize alumina produced from aluminum can waste, and to be applied as catalyst support in the biodiesel production. In this study, the alumina from aluminum can waste was produced via Sol-gel method by varying the aging time. Characterization of alumina was performed by using FTIR, XRD, BET, and SEM-EDX. The synthesized alumina was used as catalyst support for potassium nitrate catalyst to be applied in biodiesel production by using transesterification reaction of cooking oil. The biodiesel produced was analyzed by using gas chromatography-mass spectrometry (GCMS) and FTIR. The experimental results revealed that the alumina powder synthesized at room temperature have high surface area which are suitable to be used as catalyst support of producing biodiesel. In conclusion, it has been demonstrated that it is possible to produce alumina from aluminum can waste that can be used as catalyst support for biodiesel production. From the GCMS and FTIR results, it was proven that biodiesel is produced.
CO2 removal via promoted potassium carbonate with glycine: solubility measurement at elevated pressure
Authors: Isa F , Zabiri H , Shaarif M A
Published: December 2019

Potassium carbonate promoted with glycine is considered as potential candidates for CO2 removal process as it demonstrated less energy usage during the regeneration process. Hence, in order to model the process at upscale condition, the loading of CO2 into the promoted solvent is measured at temperature (30-60 0C) over the elevated pressure (10 bar) using high pressure solubility cell. The equilibrium solubility data is measured for 15wt% potassium carbonate + 3wt% glycine and 20wt% potassium carbonate +5 wt% glycine. This work aims to study the solubility of CO2 into the promoted solvent at higher operating pressure, thus the vapor liquid equilibrium (VLE) can be derived and further facilitate the development of simulation for CO2 absorption process at the upscale condition. Results show that the CO2 is less favor to absorb into the promoted solvent at high temperature since the process is exothermic, thus increasing temperature would decrease the tendency of the absorption process. The comparative analysis also showed that solubility is improved at higher pressure as greater force assist to alleviate the surface stress of the solution.
Simulation of pressurized water scrubbing process for biogas purification using Aspen Plus
Authors: Abu Seman N , Harun N
Published: December 2019

Biogas produced from anaerobic digestion process has a major amount of biomethane (bioCH4), carbon dioxide (CO2), and traces amount of impurities. It must undergo biogas cleaning first to remove the impurities depending on the requirement of the applications. Pressurized water scrubbing is the most applicable method for removing CO2 because of its simplicity, low cost, and low toxicity. This study aims to develop a pressurized water scrubbing process model for biogas purification using Aspen Plus software. Several process parameters such as absorber column pressure and liquid to gas (L/G) ratios were varied to investigate their effects on bioCH4 purity and percentage of CO2 removal. The simulated results show good agreement with previous work and agreed well with the typical standard concentration of bioCH4 of over 95% to be used as vehicle fuels or in a gas grid.
Characterization of bioactive compounds extracted from patchouli: Comparing microwave-assisted hydrodistillation and hydrodistillation methods
Authors: Abdurahman N H , Sundarajan S
Published: December 2019

Microwave-assisted hydrodistillation (MAHD) is a promising and advanced technology that uses microwave heating to extract essential oils from dry leaves. Currently available conventional methods are time consuming, thermally unsafe and require costly solvents. In the current study, MAHD and traditional hydrodistillation (HD) techniques were compared and their effectiveness in the separation of the essential oil from dry patchouli leaves have been studied. The patchouli oil that obtained from MAHD and HD extraction methods were characterized using gas chromatography-mass spectrometry (GC-MS) analysis and the impact of the two extraction methods on the plant morphology were observed using scanning electron microscopy (SEM) analysis. The results indicated that MAHD method extracted 5 % of essential oil at solid to solvent ratio of 1:12 g/ml from patchouli leaves as compared to 4 % obtained using HD method at 45 minutes of extraction time. In addition, MAHD method can retain 16 compounds while only 11 chemical compounds were extracted using HD. Thus, MAHD showed a greater potential for better production of the essential oil from patchouli leaves as compared to HD method.
Performance profiling of UV-grafted forward osmosis polyethersulfone membrane using multivariate classical scaling technique
Authors: Rahman A F H A , Mohd Yunus M Y , Nasaruddin T S L M T A , Harun N , Abu Seman M N
Published: December 2019

In this work, Classical Scaling (CMDS) method was used to develop a set of membrane profile performance for various types of UV-grafted polyethersulfone (PES) membrane. Previously, there is no such profiling has been considered. The main motivation of the profiling is to determine what is the most preference impact factor which significantly influence the membrane strength during application. Initially, nine (9) different samples of modified PES membranes were prepared mainly by adopting numerous characterization parameters of acrylic acid monomer concentration and grafting time. Three (3) performance indicators namely water permeability (A), solute permeability (B) and structural parameter (S) were used as representing the foundation of membrane performance profile. In particular, the Euclidean and City-block scales were utilized to build up the multivariate profile based on two dimension configurations. The key finding suggests that the modified membranes were easily clustered based on its grafting mechanism. From the general observation on the compressed CMDS dimensional space, samples that fall above the x-axis in Euclidean scale configuration and those scattered samples in the City-block scale have relatively larger pores. Thus, the CMDS profiling tends to favor the pore size as the dominant impact factor in characterizing the membrane performance based on the three specified parameters that investigated.
Comparison of optimal solvent extraction stages between P204 and [A336][P204] for the separation of europium and gadolinium
Authors: Ismail N A , Mohd Yunus M Y , Abdul Aziz M A , Abidin M A
Published: December 2019

This study was designed to compare between the number of extraction stages required by 2-ethylhexyl phosphoric acid mono 2-ethylhexyl ester P204 and ionic liquid-based system of [A336][P204] in a cascade counter-current extraction process for the separation of europium (Eu) and gadolinium (Gd). Eu and Gd were chosen for this study as these metals are among the strenuous due to low availability in nature and small separation factor. The value of the separation factor (β) of both extractants, was obtained from the experimental work, while other process parameters were calculated using the counter-current model developed by Xu Guangxian. Extraction of Eu using [A336][P204] was found optimum at 3.5 M of nitric acid, with organic to aqueous (O/A) ratio of 9:1, while the optimum condition for P204 was determined at 3.0 M of hydrochloric acid and 9:1 of O/A ratio. The optimized β value for P204 was identified lower (β:2.38) compared to the condition for [A336][P204] (β:3.44). In order to obtain the optimal number of separation stages, the target purity and recovery rates were set to 99.9% and 90% respectively for both extractants. From the Xu model, the results show that [A336][P204] extractant requires at a minimum of four and two extraction and scrubbing stages respectively for maintaining the desired outputs. Meanwhile, P204 extractant needs to develop at least eight extraction stages as well as five scrubbing stages to produce the same production capacity. This finding generally suggests that [A336][P204] is favorable over P204 for the separation of europium and gadolinium particularly from the viewpoint of economic interest.
Diffusion coefficients of trivalent rare earth/actinide ions in acid and alkaline aqueous solutions
Authors: Liyananadirah M S , Deraman M R , Ibrahim W H , Harun N
Published: December 2019

Leaching is one of the key process of rare earth (RE) element recovery. This paper was set out to validate the effectiveness of acid/alkali in RE leaching by measuring the limiting ionic conductivity (λo), self-diffusion coefficient (Di) and overall diffusion coefficient (DAB) to obtain a clear insight on the transport properties of ions and salts in aqueous solution. The calculation diffusivity of Di
which is diffuse individual ions in pure water and DAB
diffuse in chemical reagents were determined using Nernst-Haskell equation, applicable for 25°C. The results of D
i
were found to be consistent with experimental data from the literature where most of calculation and experiment data are less than 5% error. The final outcome had managed to confirm that NaOH is best reagent for most RE element leaching, which suits the common practice of the industry.
Supported liquid membrane for acetic acid extraction: Screening of membrane support preparation factors
Authors: Malid S A A , Saufi S M , Harruddin N
Published: December 2019

It is essential to remove acetic acid from the biomass hydrolysate during the biorefinery process. The product yield can be effected by the acetic acid due to it inhibition to the microorganism used during the fermentation. Supported liquid membrane (SLM) can be used to remove the acetic acid. The membrane support plays important role in the SLM process. However, due to the use of the commercial membrane support, lack of studied was conducted on the fabrication of custom made membrane support for the SLM process. In the current study, two level full factorial design was employed to screen three fabrication factors during preparation of polyethersulfone-graphene membrane support via vapor induced phase separation technique. The factors screened were temperature of water bath (A) (30-60 °C), exposure time (B) (10-60 s) and air humidity (C) (70-90 RH%). The response was evaluated based on the extraction percentage of the acetic acid from 10 g/L aqueous acetic acid feed solution. All three main factors were significant to the SLM performance. Air humidity factor (C) gave the highest contribution of 28.96% among the main factors. In term of the interaction between factors, water bath temperature (A) and exposure time (B) give the most significant effect with 45.01% percentage of contribution. The highest extraction percentage of the acetic acid using SLM system was 75.95% using the membrane prepare at 30 °C water bath temperature, 10 s exposure time and 70% air humidity.
23 fractional factorial design for polymer based thin film composite (TFC) membrane synthesis for CO2/CH4 separation
Authors: Ghazali A A , Roshan R K , Abd Rahman S , Abdul Wahab M S , Hazleen N S , Mandayar N
Published: December 2019

Membrane technology is dominating the industry as an attractive approach for biogas purification due to its outstanding performance. Recently, there have been intensive efforts in the development of better separation efficiency of membrane which include altering the materials and modifying the methods in preparing the membrane. A well-formed membrane is when they achieved both high permeability and excellent separation ability. Therefore, this study is focusing on identifying the best processing factors in PVC/Pebax thin film composite (TFC) membrane development towards CO2/CH4 separation by employing 23 fractional factorial design (FFD). A total of three factors; immersion times (5 & 15 min), Pebax concentration (1 & 5 wt%) and number of coating layers (1 & 4) were chosen to run simultaneously with CO2 permeability and ideal selectivity as the responses for this study. The results show that the most influential factors that affect the permeability are immersion time and Pebax concentration, while for selectivity are Pebax concentration and number of coating layer. The best condition was known to maximize the permeability and selectivity. The identified conditions were immersion time for 15 min, Pebax concentration at 5wt% and 4 layers of coating which gave CO2 permeability and gas selectivity of 19612 Barrer and 7.15, respectively. The outcome of this study indicates that FFD was suitable to minimize and eliminate factors by considering the interaction among the factors involves in membrane film synthesis for excellent gas separation performance. Besides, the existence of Pebax layer was verified by visual interpretation using Scanning electron microscopy (SEM) and Fourier Transform Infrared (FTIR).
A road map to generative safety culture: An integrated conceptual model
Authors: Shahid A , Zaidi M S , Azizan R
Published: December 2019

Evidence has shown that maturity models are a popular means of assessing safety culture in organizations. Maturity models involve defining maturity stages or levels from less to more advanced safety cultures. A maturity model is a descriptive model in the sense that it describes essential, or key, attributes that would be expected to characterize an organization at a particular level. Existing culture maturity models still lacks a concise roadmap of strategies that can guide an organization to progress through the maturity stages from less to advanced. This work proposes a concept to integrate the present general and workplace models and techniques that provides a roadmap to generative safety culture. In doing so, a summary of the current general and workplace literature will be provided, method to integrate them to develop an integrated conceptual model for a generative safety culture, as well as the final integrated model is discussed. This conceptual model can be the basis for further research in order to provide a comprehensive picture of the safety culture improvement and maturity process. Lastly, implications for specific interventions to develop targeted safety culture improvement practices and work towards achieving generative safety culture will be discussed.
Risk analysis of offshore pipeline due to third party damages
Authors: Amri E , Sulaiman N S , Alaw F A
Published: December 2019

The third party damage also known as external factor that contributed to pipeline failure was an unexpected event that considered as threats to human safety. In this work, two risk assessment approaches namely qualitative and quantitative were adopted to predict and measure the causes of offshore pipeline failure due to the third party damages. Qualitative analysis involving causal and consequences of an event was developed using Bow-tie (BT) model to determine the contributing parameter of an event. The parameters obtained were then converted to Bayesian Network (BN) for a quantitative approach. Based on the qualitative analysis, the major threats identified in third party damage were categorized into “anchor impact” and “impact” meanwhile the consequences were human safety, marine life ecosystem and economical loss. Statistical data from PARLOC 2012 were utilized for BN model and transformed into conditional probability table (CPTs). the results generated indicate that the major contribution to pipeline damage was “trawling”. The utilization of Bow-tie and BN analysis may complement the risk analysis of offshore pipeline due to third party damage for more informed pipeline maintenance decisions.
Development of compliance checklist system for landed housing construction activities
Authors: Annuar S N H S M , Sukadarin E H , Zakaria J , Aziz H A
Published: December 2019

In the construction industry (landed housing), most of the accidents and near-misses in occur due to unsafe behavior of the employers and employees. Lacking compliance with regulations is also one of the causes of accidents and near-miss occurrence in the construction industry including for landed housing development). This paper aims to identify Building Operations and Works of Engineering Construction (BOWEC) requirements under Factories and Machinery Act with Regulations (Act 139), Law of Malaysia for landed housing construction activities. Behavior-Based Safety (BBS) approach is used to develop a compliance checklist based on the BOWEC requirements. The developed checklists were validated in terms of its validity by using case study in the construction industry. After the validation processes, the final checklist is ready to be used. The final checklists are divided into two parts; (1) the checklist for the employer and (2) the checklists for employees. Workplace assessment was conducted using the developed checklist. The finding reveals that more than half of the construction activities are comply with the legal requirements.
The implementation of lean manufacturing and ergonomics in Small Medium Enterprise – Case study
Authors: Rose A N M , Ab Rashid M F F , Nik Mohamed N M Z , Jubri M A S
Published: December 2019

Productivity can be increased by eliminating of all wastes. The objective of lean manufacturing is to eliminate wastes. Commonly, there are seven wastes known as transport, inventory, motion, waiting, over processing, overproduction and defects. However, ergonomics is a process to improve the working posture by designing or arranging a workplace, system and material handling. The aim of this study is to improve the productivity through the integration of basic lean manufacturing and ergonomics in the food company. The walkthrough and distribution of questionnaire have been conducted in this company. Each activity was observed to identify non-value-added activity and work related muscular skeletal disorder (WMSD) that affect the productivity by using questionnaire, motion study and Rapid Upper Limb Assessment (RULA). The questionnaire result has shown that the most of wasted motion is in weighing and measuring activity. In addition, all workers in this process were affected by the musculoskeletal disorder at their neck and shoulder. All movement were simulated through Delmia software. The RULA score shows that the worker had experienced pain at the arm and wrist. The score also suggested that the process should be changed immediately. The changes might reduce the worker’s pain and increase the productivity.
Compression power requirements for Oxy-fuel CO2 streams in CCS
Authors: Daud N K , Martynov S , Mahgerefteh H , Nasuha N
Published: December 2019

CO2 compression systems are commonly designed assuming negligible amount of impurities in CO2 fluid, it is of practical interest to evaluate the impact of impurities in oxy-fuel streams on the compression power requirements. Compared to more traditional postcombustion and pre-combustion capture methods, oxy-fuel technology produces a CO2 stream with relatively high concentration of impurities that may require partial or a high level of removal and whose presence can be expected to increase the costs of CO2 compression. Four types of compression technologies employed include four-stage compressor with 4 intercoolers, single-stage supersonic shockwave compressor, three-stage compressor combined with subcritical liquefaction and pumping and three-stage compressor combined with supercritical liquefaction and pumping. The study depicts that decrement of the impurities content from 15 to 0.7%v/v in the CO2 streams reduced the total compression power in the compression system. The study also concludes that three-stage compressor combined with subcritical liquefaction and pumping can potentially offer higher efficiency than four-stage compressor with 4 intercoolers for almost pure CO2 streams. In the case of raw oxy-fuel mixture, that carries relatively large amount of impurities, subcritical liquefaction proved to be less feasible, while supercritical liquefaction efficiency is only marginally lower than that in the four-stage compressor with 4 intercoolers.