Wong Yee Shian
Thumbnail Image
Preferred name
Wong Yee Shian
Official Name
Wong, Yee Shian
Alternative Name
Wong, Yee-Shian
Wong, Y. S.
Wong, Yee Shian
Yee-Shian, Wong
Y S Wong
Main Affiliation
Scopus Author ID
56004092100
Researcher ID
M-6006-2015

Research Output

Filters

51
Reset filters

Settings
Now showing 1 - 10 of 51
Thumbnail Image
Publication

Synergistic Effect Between Iron and Food/Microorganism (F/M) Ratio in Biological Wastewater Treatment

2022-01-01 , Subramaniam L.S. , Nabilah Aminah Lutpi , Wong Yee Shian , Ong Soon An , Nazerry Rosmady Rahmat , Siripatana C.

Biological wastewater treatment is mainly dependent on the actions of microorganisms that can be used to treat wastewater. Microorganisms will start to stick together when they degrade the organic matter in wastewater for food and flocculate to settle the pollutants. This study aimed to investigate the effect of food to microorganism (F/M) ratio and iron in a biological process using aerobic treatment. For this purpose, four aerobic tanks (A, B, C, D) were set up using activated sludge as the seed sludge, air pump as air diffuser to provide oxygen to the system, and three litres of synthetic medium as carbon source for each tank. A specific amount of iron (II) sulfate was added into tanks B, C, and D with the weight of 3 g, 6 g, and 9 g, respectively. Tank A act as a control, and no iron dosage was added. The F/M ratio for tanks A, B, C, and D were 0.8, 0.5, 0.4, and 0.3 mg BOD/mg MLVSS, respectively. The aerobic tanks were operated for 40 days in sequential batch mode and sampling was collected four times per week to observe the COD and MLVSS. This study has found that Tank D shows the best performance compared to all tanks with 84.71% COD removal efficiency and a fivefold increment of microorganism growth rate. These findings suggest that a relationship exists between the iron and F/M ratio to enhance the aerobic treatment process.

View
Thumbnail Image
Publication

Photocatalytic Degradation of Sugarcane Vinasse Using ZnO Photocatalyst: Operating Parameters, Kinetic Studies, Phytotoxicity Assessments, and Reusability

2022-02-01 , Kee W.C. , Wong Yee Shian , Ong Soon An , Nabilah Aminah Lutpi , Sam Sung Ting , Audrey Chai Yee Chieh , Eng K.M.

Abstract: Photocatalytic degradation performance is highly related to optimized operating parameters such as initial concentration, pH value, and catalyst dosage. In this study, the impact of various parameters on the photocatalytic degradation of anaerobically digested vinasse (AnVE) has been determined through decolourization and chemical oxygen demand (COD) reduction efficiency using zinc oxide (ZnO) photocatalyst. In this context, the application of photocatalytic degradation in treating sugarcane vinasse using ZnO is yet to be explored. The COD reduction efficiency and decolourization achieved 83.40% and 99.29%, respectively, under the conditions of 250 mg/L initial COD concentration, pH 10, and 2.0 g/L catalyst dosage. The phytotoxicity assessment was also conducted to determine the toxicity of AnVE before and after treatment using mung bean (Vigna radiata). The reduction of root length and the weight of mung bean indicated that the sugarcane vinasse contains enormous amounts of organic substances that affect the plant's growth. The toxicity reduction in the AnVE solution can be proved by UV–Vis absorption spectra. Furthermore, the catalyst recovery achieved 93% in the reusability test. However, the COD reduction efficiency and decolourization were reduced every cycle. It was due to the depletion of the active sites in the catalyst with the adsorption of organic molecules. Thus, it can be concluded that the photocatalytic degradation in the treatment of AnVE was effective in organic degradation, decolorization, toxicity reduction and can be reused after the recovery process. Graphical abstract: [Figure not available: see fulltext.].

View
Thumbnail Image
Publication

Caffeine-containing wastewater treatment and bioelectricity generation in up-flow constructed wetland-microbial fuel cell: Influence of caffeine concentration, operating conditions, toxicity assessment, and degradation pathway

2022-04-01 , Teoh T.P. , Ong Soon An , Ho Li Ngee , Wong Yee Shian , Nabilah Aminah Lutpi , Oon Y.L. , Tan S.M. , Ong Y.P. , Yap K.L.

This study explored the potential of caffeine being utilized as the fuel for the microbes to produce electrons for electricity generation in up-flow constructed wetland-microbial fuel cell (UFCW-MFC). The effect of caffeine concentration was investigated to identify the availability of UFCW-MFC in the conversion of caffeine to electrons for electricity production; and the effect of operating conditions (circuit connection, supplementary aeration, and plant) was studied to determine their significance in the treatment of caffeine containing wastewater. The UFCW-MFC achieved about 98% of decaffeination efficiency regardless of caffeine concentration; while a decrease of efficiency was observed when UFCW-MFC operated without supplementary aeration and plant (~93%). COD removal efficiency decreased correspondingly to the increase of caffeine concentration, which could be contributed by the higher concentration of caffeine and its intermediates. The degradation pathway of caffeine in UFCW-MFC was explored in this study. It was remarkable that ammonia was produced and converted to ammonium ions during caffeine catabolism. Supplementary aeration and macrophyte play a crucial role in removing excess caffeine, intermediates as well as accumulated ammonium ions. The toxicity assessment revealed that caffeine was degraded to less toxic products. The closed circuit connection not only contributed to electricity generation but also enhanced the caffeine and COD removal efficiency by 4.6 and 5.4% in the anaerobic region, respectively. The increase of voltage and maximum power density from phase I to phase IV indicated that caffeine could be converted to electrons by the anaerobes for electricity production.

View
Thumbnail Image
Publication

Up-flow constructed wetland-microbial fuel cell: Influence of floating plant, aeration and circuit connection on wastewater treatment performance and bioelectricity generation

2020-08-01 , Teoh T.P. , Ong Soon An , Ho Li Ngee , Wong Yee Shian , Oon Y.L. , Oon Y.S. , Tan S.M. , Thung W.E.

The influence of floating plant (Eichhornia crassipes), supplementary aeration and circuit connection on wastewater treatment performance and electricity production using up-flow constructed wetland-microbial fuel cell (UFCW-MFC) were investigated in this study. This study was operated for four stages, where stage I was conducted without plant and aeration; stage II was planted with Eichhornia crassipes; supplementary aeration was provided in stage III; stage IV was operated in open circuit. The supplementary aeration showed the most significant effect on the performance of UFCW-MFC compared to floating plant and circuit connection. The optimum performance of wastewater treatment and electricity production was found in stage III as the oxygen was supplied by the floating plant and supplementary aeration for the degradation of organic matters as well as the generation of bioelectricity. The chemical oxygen demand (COD), NH4+ and NO3− removal efficiencies were 99 %, 96 % and 44 %, respectively. E. crassipes and supplementary aeration improved the dissolved oxygen (DO) concentration at the cathodic region and enhanced the NH4+ removal by 10 % (Stage II) and 67 % (Stage III) compared to the non-planted bioreactor (stage I). Closed circuit also performed 6 % better than open circuit at sampling point 1 (S1) in COD reduction. The maximum power density, voltage output, coulombic efficiency and normalized energy recovery were 45.46 ± 3.83 mW/m3, 291 ± 62 mV, 2.15 %, 15.09 Wh/kg COD and 0.31 W/m3, respectively.

View
Thumbnail Image
Publication

Biohydrogen production from palm oil mill effluent with Moringa Oleifera seeds as support carrier in attached growth system

2020-06-10 , Hamid W.Z.W.A. , Nabilah Aminah Lutpi , Wong Yee Shian , Ong Soon An , Malek M.A.

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.

View
Thumbnail Image
Publication

Effect of operating temperature in the anaerobic degradation of palm oil mill effluent: Process performance, microbial community, and biokinetic evaluation

2022-09-01 , Audrey Chai Yee Chieh , Wong Yee Shian , Ong Soon An , Nabilah Aminah Lutpi , Sam Sung Ting , Kee Wei Chin

This research paper presents the thermophilic anaerobic digestion (TAD) of palm oil mill effluent (POME), which is an extension of a previously conducted mesophilic anaerobic digestion (MAD) study. An anaerobic suspended growth closed bioreactor was operated at various hydraulic retention times (HRT) between 24 and 8 days. The effect of operating temperature on the performance, microbial identification, and biokinetic coefficients was evaluated. Performance was quantified by the production of biogas and the chemical oxygen demand (COD) reduction efficiency. Biogas production in TAD (64.56 L/day) was higher than MAD (46.76 L/day). A higher COD reduction efficiency was also achieved in TAD (90.90%) compared to MAD (89.66%). Other than that, more species of methanogenic bacteria were also identified in TAD through 16S rDNA. Furthermore, the modified Monod model implemented in the biokinetic evaluation revealed that higher values of maximum substrate utilization rate (rx,max) and maximum specific biomass growth rate (μmax) contributed to the better performance in TAD. The high rx,max value explains the higher COD reduction efficiency obtained in TAD. The critical retention time (θC) in TAD is also higher than MAD, making it less prone to the washout of active microbes when operating near low retention times. Additionally, TAD also achieved higher methane yield (YCH4) as opposed to MAD. The extension study concluded that the TAD of POME demonstrated improved performance in terms of biogas production and COD reduction when evaluated against the previously conducted MAD.

View
Thumbnail Image
Publication

Hybrid system of photocatalytic fuel cell and Fenton process for electricity generation and degradation of Reactive Black 5

2017-01-01 , Noradiba Nordin , Ho Li Ngee , Ong Soon An , Abdul Haqi Ibrahim , Wong Yee Shian , Lee Sin Li , Oon Yoong Sin , Oon Yoong Ling

A novel hybrid system composed of a photocatalytic fuel cell (PFC) and Fenton reactor was developed with the aim to degrade the azo dye Reactive Black 5 (RB5) and generate electricity. Compared to previously established system of bioelectro-Fenton system, microbial fuel cell (MFC) system has significant challenge in the development and operation system. Therefore, PFC is used instead of MFC to generate electrons for the Fenton system. The effect of azo dye (RB5) on each PFC and Fenton reactor was investigated. The experimental results showed that maximum power output was achieved in the absence of dye in the Fenton reactor of this hybrid system. Furthermore, higher degradation efficiency of RB5 could also be observed in the PFC reactor in this hybrid system.

View
Thumbnail Image
Publication

Transformation from biofiltration unit to hybrid constructed wetland-microbial fuel cell: Improvement of wastewater treatment performance and energy recovery

2023-05-01 , Teoh T.P. , Koo C.J. , Ho Li Ngee , Wong Yee Shian , Nabilah Aminah Lutpi , Tan S.M. , Yap K.L. , Ong Soon An

This study aimed to compare the performance of biofiltration, constructed wetland, and constructed wetland microbial fuel cell (CW-MFC). The transformation from a biofiltration unit to a hybrid CW-MFC was demonstrated with the advantages of improvement of wastewater treatment while generating electricity simultaneously. The introduction of plants to the upper region of the bioreactor enhanced the DO level by 0.8 mg/L, ammonium removal by 5 %, and COD removal by 1 %. The integration of electrodes and external circuits stimulated the degradation rate of organic matter in the anodic region (1 % without aeration and 3 % with aeration) and produced 5.13 mW/m3 of maximum power density. Artificial aeration improved the nitrification efficiency by 38 % and further removed the residual COD to an efficiency of 99 %. The maximum power density was also increased by 3.2 times (16.71 mW/m3) with the aid of aeration. In treating higher organic loading wastewater (3M), the maximum power density showed a significant increment to 78.01 mW/m3 (4.6-fold) and the COD removal efficiency was 98 %. The ohmic overpotential dominated the proportion of total loss (67-91 %), which could be ascribed to the low ionic conductivity. The reduction in activation and concentration loss contributed to the lower internal resistance with the additional aeration and higher organic loading. Overall, the transformation from biofiltration to a hybrid CW-MFC system is worthwhile since the systems quite resemble while CW-MFC could improve the wastewater treatment as well as recover energy from the treated wastewater.

View
Thumbnail Image
Publication

Pilot scale single chamber up-flow membrane-less microbial fuel cell for wastewater treatment and electricity generation

2017-04-06 , Thung W.E. , Ong Soon An , Ho Li Ngee , Wong Yee Shian , Fahmi Muhammad Ridwan , Oon Yoong Ling , Oon Yoong Sin , Harvinder Kaur Lehl

Pilot scale up-flow membrane-less microbial fuel cell (UFML-MFC) was constructed to study feasibility of the bioreactor for simultaneous degradation of organic substance and electricity generation. The performance of the UFML-MFC was evaluated with different anode electrode (cube carbon felt and stacked carbon felt) in terms of voltage output, chemical oxygen demand (COD) and Coulombic efficiency (CE). Carbon flake were used as cathode in the UFML-MFC. UFML-MFC was operated in three stages where included batch-fed, end of batch fed and semi-continuous. The Cube carbon felt as anode have the better performance in terms of voltage output and electricity generation in all 3 stages. Maximum voltage output was 0.311 ± 0.004 V at 75% of COD reduction and thus CE was 0.15%. The result shows the operational mode is the key to improve the voltage output and also COD reduction.

View
Thumbnail Image
Publication

Microbial fuel cell operation using monoazo and diazo dyes as terminal electron acceptor for simultaneous decolourisation and bioelectricity generation

2017-03-05 , Oon Yoong Sin , Ong Soon An , Ho Li Ngee , Wong Yee Shian , Oon Yoong Ling , Harvinder Kaur Lehl , Thung Wei Eng , Noradiba Nordin

Monoazo and diazo dyes [New coccine (NC), Acid orange 7 (AO7), Reactive red 120 (RR120) and Reactive green 19 (RG19)] were employed as electron acceptors in the abiotic cathode of microbial fuel cell. The electrons and protons generated from microbial organic oxidation at the anode which were utilized for electrochemical azo dye reduction at the cathodic chamber was successfully demonstrated. When NC was employed as the electron acceptor, the chemical oxygen demand (COD) removal and dye decolourisation efficiencies obtained at the anodic and cathodic chamber were 73 Â± 3% and 95.1 Â± 1.1%, respectively. This study demonstrated that the decolourisation rates of monoazo dyes were ∼50% higher than diazo dyes. The maximum power density in relation to NC decolourisation was 20.64 mW/m 2 , corresponding to current density of 120.24 mA/m 2 . The decolourisation rate and power output of different azo dyes were in the order of NC > AO7 > RR120 > RG19. The findings revealed that the structure of dye influenced the decolourisation and power performance of MFC. Azo dye with electron-withdrawing group at para substituent to azo bond would draw electrons from azo bond; hence the azo dye became more electrophilic and more favourable for dye reduction.

View