bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microwave-assisted in situ transesterification of wet microalgae for the production of biodiesel: progress review
Authors: Fazril I , Shamsuddin A H , Nomanbhay S , Kusomo F , Hanif M , Ahmad Zamri M F M , Akhiar A , Ismail M F 
Published: June 2020

Abstract
Continuous efforts are done by scientists in the quest of finding sustainable alternatives for fossil fuels. Various feedstock have been carefully selected to be utilized in the production of biodiesel. Microalgae has garnered a lot of attention as early as in the 80s and is regarded as one of the most promising feedstock to displace fossil fuel. However, the utilization of microalgae as feedstock in a mass production of biodiesel comes with considerable challenges. One of the main obstacles is the high cost involved in processes such as drying and the subsequent lipid extraction of the biomass. These two energy extensive processes created a bottleneck in the biodiesel production at a large scale. As a remedy, direct or in situ transesterification of the wet microalgae biomass can be applied to entirely circumvent the two processes; hence substantially reducing the production cost. However, the presence of water in the wet microalgae biomass posed a challenge in the transesterification process. This paper covers the specific techniques of utilizing microwave irradiation during the in situ transesterification of wet microalgae biomass.
Properties and environmental impact of available firewood in Brunei Darussalam
Authors: Yazdani M G , Ligoh N. , Ali M.H. 
Published: June 2020

Abstract
Five types of firewood used in Brunei Darussalam is identified. Properties, such as wood density, moisture percentage, ash content and elemental composition of plants were determined and correlated with the calorific value and evaluated in relation to their properties and environmental impact when burned. It was revealed that the firewood with the highest calorific value does not necessarily constitute the best option as fuel, if elemental composition is taken into account. The variation of the wood density, calorific value, ash contains and elemental composition C, N, and their indirect impact on the environment are discussed in this paper.
Effect of operating parameter on the anaerobic digestion oil palm mesocarp fibre with cattle manure for biogas production
Authors: Saidu M , Yuzir A , Salim M R , Richard A , Afiz B 
Published: June 2020

Abstract
Anaerobic digestion is a complex biological process resulting in the conversion of biodegradable organic matter into biogas and mineralized material. Anaerobic digestion involves the breakdown of biomass by a concerted action of a wide range of microorganisms in the absence of oxygen. The biological pre-treatment was used to reduce the lignocellulose content of substrate. Laboratory experiment was carried out in single stage 10 L bioreactors. The reactors were named R1, to R10 at different mixture conditions with organic loading of 1.62 and 2.11 g VS at HRT of 10 days. The result was stable at the initial stage, within the first 10 days was high and was attributed to the consumption of easily degradable COD. These indicate that there is stable COD removal efficiency for the anaerobic digestion of treated OPMF with CM and seeded with POME. The results showed the level of COD removal efficiency was observed and upon the steady state of the reaction. In this experiment, the results indicate that chemical oxygen demand (COD) reduction in reactor R1 shows the best result of the average removal efficiency value of 37.9 %. Although, ambient temperature was adopted, it still shows a high COD removal efficiency in R1 and may be associated to a more stable reaction. This indicated that pre-treated OPMF produced a better COD removal efficiency than the untreated OPMF. The removal efficiency started with 18 % and continued to increase to 38 %. The removal efficiency became relative stable until day 30 which give the highest percentage removal of 45 % which was achieved with a high OLR (2.11 kg VS L−1 d−1). The reductions continued in the same trend until day 20 and remained stable till the end of the experiment. This indicates that the available microorganisms have been exulted by day 20 and this corresponds to a drop to the rate of biogas production. Operating parameters considered in this study have an influence on the rate of biogas produced during anaerobic digestion. The results show that COD, do influence the rate of biogas production.
Interlocking compressed earth bricks as low carbon footprint building material
Authors: Asman N S A , Bolong N , Mirasa A K , Asrah H , Saad I 
Published: June 2020

Abstract
The building construction significantly contributes to the carbon growth due to the high carbon emissions produced by buildings and their effects on climate change. Malaysia has devoted to reduce the carbon dioxide emission by the year of 2020. Therefore, the Interlocking Compressed Earth Bricks (ICEB) has been introduced as an alternative for low carbon building material. This paper studies the carbon footprint of Interlocking Compressed Earth Bricks as a walling structure in buildings or residential houses. The Interlocking Compressed Earth Bricks system is an improvement from the conventional brick production where the brick is fabricated by compressed method (not fired), thus reducing the carbon emissions. This paper presents a cradle-to-gate carbon emission study of a multi-story residential building in a Community house in Tawau, Sabah by using the life cycle assessment (LCA) methodology. The total carbon of the buildings using conventional FCB and ICEB construction are 405.75 kgCO2/m2 and 264.50 kgCO2/m2, respectively, which are comparable with the results of similar studies found in the literature. In order to achieve low-carbon buildings for the residential houses in Sabah, the use of ICEB as alternative materials with low carbon intensities and sustainable construction practices are suitable and recommended. The result shows that the implementation of Interlocking Compressed Earth Bricks contributes to carbon footprint reduction of 35% from the conventional and suitable to be used as a low carbon footprint building material.
Citrus aurantiifolia and citrus microcarpa fruit peels waste as eco-friendly natural coagulants
Authors: Dollah Z , Sahat N A , Hamzah N , Musir A A , Ramli R 
Published: June 2020

Abstract
Turbidity is one of the importance of physical water quality parameter in the water treatment process. Aluminum sulfate (alum) and ferric chloride are the most widely groups of chemical coagulant and have been extensively used to remove turbidity. However, there are several flaws relates to the environmental issue and impose health risk to the consumer. Fruit peel waste as a natural coagulant is one of the alternative techniques in minimizing the usage of chemical coagulant in water treatment. This research focused on a combination of ratio 60:40 and 80:20 of citrus microcarpa peels and citrus aurantiifolia peels to act as a natural coagulant for turbidity removal. Furthermore, the effect of mixing duration is determined to establish the optimum mixing duration for the highest turbidity removal. Standard practice using jar test were performed in synthetic turbid water using kaolin. The highest turbidity removal occurred at optimum ratio of 80:20 with 77.6% efficiency removal where the optimum mixing duration was found to be at 120 rpm of rapid mixing at 3 minutes, 50 rpm of slow mixing at 20 minutes and 60 minutes of settling time. The study demonstrated that combination of citrus aurantiifolia peels and citrus microcarpa peels have the potential to be used as natural coagulant for a future alternative in water treatment.
Recovery of nano-lignin from anaerobic treated palm oil mill effluent (AT-POME)
Authors: Ismail H S , Ibrahim A H , Abidin C Z A , Ridwan F M 
Published: June 2020

Abstract
Lignin is the main polymers in woody biomass aside cellulose and hemicelluloses Recently, nano-lignin is gaining importance due to the increasing demand for bio-based and bio-active nanomaterial fillers for many applications such as in composite and textile industries. Palm oil mill effluent (POME) is the main wastewater produce by palm oil mills. Anaerobically treated (AT-POME) contains high soluble lignin due to the anaerobic digestion of cellulosic material in POME. Nano-lignin was precipitated by adjusting the initial pH of AT-POME during the sonication process. Sulfuric acid (H2SO4), nitric acid (HNO3), hydrochloric acid (HCl) and phosphoric acid (H3PO4) were used to adjust the initial pH of AT-POME. Result shows that sulfuric acid was the most suitable acid to be used as it could recovered 96% of the soluble lignin in AT-POME. The presence of ultrasonic during the precipitation process had reduced the size to 383.4 nm. The optimum operating parameter for lignin recovery is at pH 4 using sulfuric acid and sonicated at 80 watts for 15 minutes. This study shows that sonication could reduce the size of precipitated lignin from AT-POME. In addition, removal of lignin from AT-POME also reduced the COD content of AT-POME.
The development of wastewater coagulant derived from Artocarpus heterophyllus
Authors: Zakaria H A , Mansor W S W , Zahari N S 
Published: June 2020

Abstract
Conventional method of wastewater treatment may include the usage of inorganic coagulants which may cause significant environmental effects. This research was carried out to focus on development of coagulant derived from Artocarpus heterophyllus as wastewater treatment agent. In this research, the coagulant derived from Artocarpus heterophyllus seeds and peels was produced by chemical activation process. Samples were prepared in the form of powder at 90 micromillimeter pore size and sulphuric acid (H2SO4) with concentration of 0.6M was used as activation agent and the activation temperature was set at 400°C for two hours. The coagulant samples were prepared by dissolving the seeds and peels of Artocarpus heterophyllus with H2SO4 at 1:8 (w/v) ratios then 0.1g of each sample was tested against 10ml of synthetic kaolin wastewater. The physical and chemical characterization of the sample was done by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM) and Brunauer, Emmet and Teller (BET) while the adsorbent effectiveness were tested using turbidity meter. FTIR results showed that the functional group in the samples corresponds well with existing literatures. XRD analysis has found that the samples were amorphous in structure. The BET surface area of Artocarpus heterophyllus coagulant seeds and peels is 216.8152 m2/g and 281.0723 m2/g respectively proved that the surface area of both samples become larger after heated which signifies larger surface area and pore diameter of the adsorbent. Result obtained through turbidity meters found that 11% (w/v) Artocarpus heterophyllus seeds coagulant showed 59.69% in turbidity removal while 14% (w/v) Artocarpus heterophyllus peels coagulant showed 76.88% in turbidity removal. This study had confirmed the efficacy of Artocarpus heterophyllus as coagulant up to an acceptable degree, however further study are needed to guarantee better percentage in turbidity removal.
Study of water quality for Sungai Perlis, Perlis during high and low tides
Authors: Che Ali S N A , Kamarudzaman A N , Jalil M F Ab 
Published: June 2020

Abstract
The aims of the study are to establish the pollutant profile along Sungai Perlis during high and low tides based on physical and chemical parameters and relate the water quality with the land used along the river. Sungai Perlis is the main river in Perlis, Malaysia with size of river basin approximately 310 km2. Three station points were selected along Sungai Perlis which are one station at the upstream, one station at the middle stream and one at the downstream. Six parameters were selected which are DO, BOD, COD, TSS, AN and pH. From the findings, the water quality index during high tide for upstream and downstream of Sungai Perlis are in Class II, whereas during low tide, it classified in Class III. However, no changes in water quality index during high and low tides for middle stream of Sungai Perlis, which is in Class III. The pollutant profiles also showed that the river were less polluted during high tide compared to low tide. The land use activities along Sungai Perlis include residential areas, recreational, agricultural, commercial, construction and fisheries located at Kuala Perlis which are directly and indirectly also contributes to the water quality of Sungai Perlis.
Study on biohydrogen production using different type of carrier materials in attached growth system
Authors: Ashah M A , Lutpi N A , Wong Y S , Ong S A , Malek M A 
Published: June 2020

Abstract
Renewable energy is known as clean energy with free from greenhouse gas emissions and global warming effects. It is generated from natural resources and one of the most promising renewable energy is biohydrogen. Biohydrogen production gets a great attention around the world because it could remove organic biomass and at the same time supplying clean hydrogen energy. In this study, three support carriers were used namely granular activated carbon (GAC), glass beads (GB) and moringa oleifera seeds (MOS). The main keys of this study was to identify the best support carrier that capable to enhance the biohydrogen production in attached growth system using Palm Oil Mill Effluent (POME) as feedstock. On the other hand, the physicochemical of the attached-biofilm were also investigated by using Scanning Electron Microscopy (SEM). Other parameter such as hydrogen concentration, volume of biogas, and kinetic study by using modified Gompertz equation has also been studied. At the end of the study, the best performance of biohydrogen production was performed by using GAC with hydrogen yield (HY) = 1.52 mol H2/mol glucose and the hydrogen production rate (HPR) = 58.50 mmol H2/l.d, followed by GB which is HY = 1.43 mol H2/mol glucose and HPR = 54.840 mmol H2/l.d and the last, MOS with HY = 1.08 mol H2/mol glucose and HPR = 41.44 mmol H2/l.d. This study has shown that proper selection of support carrier could reflect the evolution of biohydrogen production.
Biohydrogen production from palm oil mill effluent with Moringa Oleifera seeds as support carrier in attached growth system
Authors: Hamid W Z W A , Lutpi N A , Wong Y S , Ong S A , Malek M A 
Published: June 2020

Abstract
Biohydrogen production by dark fermentation is one of the attracting alternatives for renewable energy in worldwide. By employing immobilized cells, hydrogen production and cell density could be improved. This study aimed to investigate the efficiency of Moringa Oleifera Seeds (MOS) immobilized cells in enhancing the biohydrogen production using repeated batch fermentation under mesophilic condition, 37°C. The efficiency of MOS as support carrier, effect of the initial pH (5.0-7.0) and performance of raw and diluted Palm Oil Mill Effluent (POME) using MOS immobilized cells were investigated using anaerobic sludge as inoculums. The cumulative hydrogen production results were fitted into a modified Gompertz equation to find the maximum hydrogen production. MOS immobilized cells was more efficient in producing hydrogen compare to suspended cells (without MOS). The optimal pH obtained using MOS immobilized cells was found to be at pH 6 using raw POME with the maximum hydrogen production (Hm) of 122 mL, the maximum hydrogen production rate (Rm) of 39.0 mL/h, and 560 ppm of hydrogen concentration.
Analysis of sediment load under combined effect of rainfall and flow
Authors: Shams S , Ratnayake U , Abdul Rahman E K , Alimin A A 
Published: June 2020

Abstract
An increase in sediment load resulting from extreme weather event can affect the capacity of existing water infrastructure, for example, decreasing reservoir capacities, creating obstacles and reducing the navigation depth, or eroding bridge piers by scouring actions. A number of studies have been carried out on factors affecting sediment yield and transport but only a few studies being done on the combination of both rainfall and flow on the sediment load. Therefore, the aim of this study is to identify the impact on sediment load comprising of well-graded silica sand due to combined effect of flow and rainfall. This research has two objectives; firstly, to study the relationship between flow, rainfall, and sediment load and secondly to devise an experiment to investigate how combination of flow and rainfall could affect sediment load with the help of Advanced Environmental Hydrology System. Thirty-six sets of experiments were conducted on a 2 m long, 0.2 m wide and 0.15 m deep channel, moulded in the Armfield S12 MKII on a 1% constant slope with six different readings of rainfall ranging from 6 to 72 mm/hr and by varying the flow ranging from 0.5 to 3.0 L/min to observe the different trends and changes to sediment load when rainfall and flow varies. This experimental study demonstrates a combination of both rainfall and flow resulted in a stronger linear correlation with sediment load.
Increasing awareness on household rainwater tanks as supplementary water supply for island municipality in the Philippines
Authors: Gato-Trinidad Shirley 
Published: June 2020

Abstract
The Australia-ASEAN Council of the Department of Foreign Affairs and Trade through Swinburne University of Technology implemented the project, “Australian Design Rainwater Tanks for Households and Schools in the Philippines”. The project involved working with relevant local counterparts for proper design, installation and management of rainwater tanks for effective rainwater harvesting from schools and households in Philippines. A Local Government Unit staff and rainwater tank supplier and installer from the Philippines visited Melbourne to learn more about the storm water management projects by Knox City Council, SouthEast Water and the water supply treatment plant operated by Melbourne Water. A rainwater tanks manufacturer in Melbourne was also visited to keep inform of the latest design, proper installation and management of rainwater tanks. The project also involved the installation of rainwater tanks to schools and households in Dimasalang, an island municipality in the Philippines. Data collection on water consumption from rainwater tanks is in progress.
Multivariate statistical assessment of Klang River, Selangor, Malaysia
Authors: Manaff A I N A , Muhammad N S , Abdullah J 
Published: June 2020

Abstract
Rivers are the main source of raw water supply in Malaysia, which accounts for more than 80% of the total resources. Currently, development activities, industrial areas and other socio-economic activities have affected the quality of river water, especially in Sungai Klang. The main objectives of this study are to determine the water quality classification for several stations along Klang River and to perform multivariate statistical analysis of the water quality data. A total of 13 monitoring stations and 6 water quality parameters from 2005 to 2014, provided from the Department of Environment, Malaysia were analysed. This study found that the water quality varies spatially and temporarily. Klang River is classified as clean and polluted the upstream and downstream of the river, respectively. However, in general, Klang River is considered as polluted and thus extensive treatment is required before it can be used for domestic purposes. This study also found that the water quality of Klang River is affected by the land use activities surrounding area.
Performance evaluation of a retrofitted multi-cyclone using computational fluid dynamic
Authors: Dewika M , Rashid M , Hasrizam C M , Khairunnisa M P , Norruwaida J , Sara Y Y 
Published: June 2020

Abstract
Multi-cyclone is widely used in industries as air pollution control device due to several advantages over other available separation units such as its low capital, operating, and maintenance cost and as well as its usability under a wide range of operational conditions. However, it is merely a pre-cleaner as it is inefficient in collecting fine particulate especially, particulate matter with size less than 10 µm (PM10) and below. Hence a simple, cost-effective retrofit on a Conventional Multi-cyclone (CMC) with the motivation of increasing its overall performance on fine particulate emission control was carried out. The retrofit was performed by creating higher negative pressure inside the dust hopper of the CMC by extracting 10% and 24% from the total volumetric airflow rate of the unit with the means of an external Induced Draft Fan. The Computational Fluid Dynamics (CFD) with Reynold Stress Model (RSM) turbulence model was performed and validated using experimental data to gain a better understanding in pressure distribution, velocity profile and particulate movement between the CMC and the Retrofitted Multi-cyclone (RMC). The CFD results show deviation between 0% to 8% for pressure at inlet and outlet of cyclone compared to the experimental results. In addition, CFD results depict that the RMC has higher pressure at the inlet and lower pressure inside dust hopper of CMC, which cause the finer particle to be pulled in through suction outlet. Also, the emission of fine particulate is reduced in RMC by 9% to 16%. compared to the CMC. Moreover, the phenomena at the suction duct can be clearly explained with the usage of CFD. The finding suggests that a simple, cost-effective retrofit at the multi-cyclone has increased the overall performance in the fine particulate collection, and the understanding of the phenomena could be enhanced by the CFD.
Utilising formulated filter aids for toluene removal in filtration plant
Authors: Masdiana N. , Rashid M. , Norruwaida J. , Hajar S. , Nabila Z. , Ammar M. R. 
Published: June 2020

Abstract
Filtration together with dry sorbent injection of activated carbon is widely used for VOCs removal in contaminated flue gas in incineration process. In addition, the sorbent acts as filter aids to the fabric media that enhance the efficiency of the filtration process. This study introduced a newly three in one formulated filter aids known as PrekotAC, which is a combination of PreKot™ and activated carbon. Similarly, a four in one filter aids known as TrikotAC, a combination of three materials PreKot™, activated carbon and lime is also introduced in this study. The adsorption of the formulated PrekotAC10:90 and TrikotAC10:5:85 on toluene was investigated in this study. The results showed that PrekotAC10:90 was able to adsorbed more toluene compared to TrikotAC10:5:85. However, formulated filter aids TrikotAC10:5:85 able to reduce the pressure drop across the filtration plant compared to PrekotAC10:90. The ability to reduce pressure drop in fabric filtration system means that the formulated material able to prolong the cleaning cycle of the filter plant which simultenously preserve the life span of the filter bag.