Kesan kepekatan mangan terhadap biojerapan mangan oleh pencilan Bacillus cereus tempatan

Masalah pencemaran mangan (Mn) yang terkandung dalam air sangat bertoksik kepada hidupan kerana boleh menyebabkan pengumpulan pada gastro usus, penurunan tahap hemoglobin dalam darah, ketoksikan saraf, rasa mual, air kelihatan coklat kemerahan, dan juga paip tersumbat. Dalam ujikaji yang dijalankan, Mn yang terkandung dalam air dirawat dengan menggunakan pencilan Bacillus cereus tempatan. Biojerapan mangan dilakukan dengan menggunakan tiga kepekatan mangan iaitu 25, 40 dan 100 mg/L. Analisis yang terlibat dalam kajian ini adalah analisis ketumpatan optik (OD), pH, kepekatan mangan, biojisim dan unit pembentukan koloni (CFU). Keputusan menunjukkan OD, pH dan juga biojisim meningkat mengikut masa menggambarkan pertumbuhan bakteria. Kepekatan Mn menurun daripada 25, 40 dan 100 mg/L kepada 10.2, 18.6 dan 52.2 mg/L dengan peratus penyingkiran masing-masing sebanyak 55, 53 dan 50 % selepas 48 jam tempoh eraman. Manakala peratus pengambilan Mn oleh B.cereus menurun apabila kepekatan awal Mn ditingkatkan. Oleh yang demikian, proses biojerapan Mn oleh pencilan B.cereus tempatan dipengaruhi oleh peningkatan kepekatan awal Mn

Biological treatment of Pb and Zn using sequencing batch reactor

Effective wastewater treatment is essential to prevent water resources from being polluted. Usually, wastewater treatment can be divided into three distinct types; physical, chemical and biological treatment. This research aims to biologically treat Pb and Zn using the Sequencing Batch Reactor (SBR) system. There were four stages involved in the operation of SBR, which include; filled, react, settle and draw. The dissolved oxygen (DO) was controlled in the range of 2-5 mg/L, while the pH was maintained at the range of pH 6.5-7.5. Synthetic wastewater was used as influent with a C:N ratio of 200:40. In total, there were three HRT’s tested, which were 8, 24 and 48 hrs respectively. Additionally, the water quality parameters analysed were (chemical oxygen demand) COD, ammonium, mixed liquor suspended solid (MLSS) and heavy metal Pb and Zn in the effluent. The average percentage of COD removals in this research was 66.0% while the average heavy metal removal for Pb and Zn were 97.1% and 94.7%, respectively. Therefore, based on the three hydraulic retention times, (HRT’s), HRT 48 showed the highest performance in removing Pb and Zn

Nurturing Innovative and Creativity Through Open Ended Laboratory: JKKP Experience

AbstractInnovative approaches that require active involvement of the students in the learning activities are necessary to ensure the targeted learning outcomes are achieved. An open ended laboratory (OEL) assignment is introduced as part of the effort to provide suitable learning platform. This paper describes the implementation of the OEL and its impact on the overall students learning experience. They are graded based on the originality, creativity and innovation of their laboratory assignment as well as presentation of results and discussion. Initially we found the students faced some difficulties because they were not familiar with such laboratory assignment. Marks for innovation and creativity in the OEL assignments were found to be more than 50%, indicating that students innovative and creativity were nurtured during this assignment

Application of Response Surface Method in Reverse Osmosis Membrane to Optimize BOD, COD and Colour Removal from Palm Oil Mill Effluent

Palm oil mill effluent (POME) is typically non-biodegradable and has high concentration of organic matter that represented as COD, BOD and Colour values. The correlation of concentration and pH of POME, and Trans membrane pressure (TMP) of Reverse Osmosis (RO) membrane was optimized by response surface method using a second order polynomial model with central composite design (CCD) which is a part model of response surface method (RSM) in Design-Expert® software. The main limits that influenced the parameters removal i.e. concentration of POME, pH of solution and transmembrane pressure were empirically determined at laboratory level and successfully optimized using RSM. The best conditions were determined from 3D response surface and 2D contour graphs i.e. 10.05% of POME concentration at pH 3.0 and TMP 0.50 kPa to yield the last values of COD, BOD and Colour i.e. 24.1372 mg/L,  24.33 mg/L and 11.76 PtCo, respectively.  The results show that the response surface method effective to reduce the number of experiment

Enhancement in Monitoring for Integrated Project Implementation

AbstractIntegrated project for Year III has been introduced by the Department of Chemical and Process Engineering since 2007/2008 session. This project integrates three or four compulsory subject for each semester. The purpose of this project was to minimize student work load and help student to understand how each courses are related. Project monitoring is one of the procedures to evaluate the performance of integrated project. Since implementation of this project, the coordinator of integrated project will give feedbacks to the students on their performance after they have completed presenting their project. Even though this method is quite sufficient for student to learn their mistake unfortunately similar mistakes was repeated during their final year design project in final year. In order to overcome this problem, student self-assessment for integrated project was introduced during Semester II, Session 2011/2012. The results show that the students were able to detect their mistakes and errors, and some correction was done to their project

Recognition of Relevant ORP, pH, and DO Bending Points in Ammonia Removal from Drinking Water through Online BAF System

This study was undertaken to identify the relevant bending points in ORP, pH, and DO profiles in ammonia removal through online monitoring. A novelty BAF system as newl application for drinking water treatment that equipped with ORP, pH, DO NH4 + and NO3 − sensors was used. Two types of polluted drinking water strength (low and high strength) with various NH4 + concentrations and aeration flow were treated at a fixed-time reaction of 24 h. Experiments were conducted at four track studies (TS) of TS1 (NH4 += 50 mg/L, aeration = 0.3 L/min), TS2 (NH4 + = 100 mg/L, aeration = 2.0 L/min), TS3 (NH4 += 100 mg/L, no aeration) and TS4 (NH4 += 10 mg/L, aeration = 0.1 L/min). The results showed that the removal of NH4 + was more than 95% for TS1, TS2, and TS4. From the online monitoring performances, DO elbow and ammonia valley appeared in ORP and pH profiles, respectively. Similarly, new positive plateaus were observed in DO, indicating that the nitrifiers stopped to consume the DO after NH4 + was completely removed. Hence, based on the bending points, the aeration system is possible to be automatically stopped just after DO elbow and ammonia valley appears in order to save the energy consumption and to shorten the time demands for the drinking water treatment process

Characterization of chromate reducing Pseudomonas aeruginosa strain Mie3 isolated from Juru River sludge and its potential on Azo dye decolorization

Chromate and azo dyes are common compounds used in the industrial applications and released into the environments. Therefore studies of bioremediation treatment methods should involve the removal of both pollutants. In this study, we report, a novel chromate reducing bacteria with the capability to decolorize 4 type of dye namely Amaranth Dye, Biebrich Scarlet, Direct Blue 71 and Methanil Yellow under aerobic conditions. The isolate identified as Pseudomonas Aeruginosa strain MIE3 and reduced 52% of 150 ppm potassium dichromate (Cr(VI)) in the nutrient broth after 24 hours incubation under shaking condition at 150 rpm. Optimization using one factor at a time (OFAT) showed the optimal conditions for chromate reduction include nutrient broth concentration was 8 g/L, temperature between 30 and 35oC, and pH was 7.8. The ability of this bacterium to detoxify these toxicants make the bacterium a valuable tool for future wastewater and soil bioremediation

Biogas production under different inoculum to palm oil mill effluent ratio

Palm oil mill effluent (POME) is a wastewater generated from palm oil industries that rich with organic and nutrients which can becomes an excellent substrate for biogas production. A comprehensive study was carried out to study the effect of different ratio of inoculum to POME substrate for biogas production. In addition, the removal efficiencies of biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammoniacal nitrogen (AN), total nitrogen (TN) total suspended solid (TSS), volatile suspended solid (VSS) were also evaluated. Bio-methane potential (BMP) was used by manipulating temperature and HRT which were set to 28-32 °C and 30 days. The BMPs were operated under different ratio of inoculum to substrate at ratio of 20:80, 30:70 and 40:60. Highest cumulative biogas yield obtained was 1990 mL in the BMP containing 30:70 (inoculum:substrate) followed by the ratio of 40:60 with 1055 mL and 20:80 with 345 mL. Maximum TSS and VSS removal efficiency were 27% and 55%, recorded in 30:70 respectively, while in 40:60 and 20:80 were 23% and 12% and 8% and 51% respectively. The removal of TN was also high at 30:70 with 79% removal. Removal efficiency of COD was in BMP of 20:80 with 54% removal while BOD removal was seen the highest in 40:60 ratio BMP. Lastly, the AN were managed to be removed about 95% in 20:80 BMP. The results obtained in this study indicated that with different ratio od inoculum to POME substrate can enhance biogas production and quality of POME prior discharge to environment

Statistical optimization of the phytoremediation of arsenic by ludwigia octovalvis in a pilot reed bed using response surface methodology (RSM) versus an artificial neural network (ANN)

In this study, the removal of arsenic (As) by plant, Ludwigia octovalvis, in a pilot reed bed was optimized. A Box-Behnken design was employed including a comparative analysis of both Response Surface Methodology (RSM) and an Artificial Neural Network (ANN) for the prediction of maximum arsenic removal. The predicted optimum condition using the desirability function of both models was 39 mg kg-1 for the arsenic concentration in soil, an elapsed time of 42 days (the sampling day) and an aeration rate of 0.22 L/min, with the predicted values of arsenic removal by RSM and ANN being 72.6% and 71.4%, respectively. The validation of the predicted optimum point showed an actual arsenic removal of 70.6%. This was achieved with the deviation between the validation value and the predicted values being within 3.49% (RSM) and 1.87% (ANN). The performance evaluation of the RSM and ANN models showed that ANN performs better than RSM with a higher R2 (0.97) close to 1.0 and very small Average Absolute Deviation (AAD) (0.02) and Root Mean Square Error (RMSE) (0.004) values close to zero. Both models were appropriate for the optimization of arsenic removal with ANN demonstrating significantly higher predictive and fitting ability than RSM

The aeration effect in pilot reed bed to phytoremediate water containing Lead (Pb)

A pilot reed bed study was conducted with the aid of aeration to remove lead (Pb) contaminated water using Scirpus grossus L. f. The plants were grown in sand medium in pilot-scale reed beds, and exposed to water containing Pb in a various concentration (10, 30 and 50 mg/L) with aeration rate of 2 L/min. The samples were taken on day-1, day-14, day-28, day-42, day-70 and day-98. The results showed that Pb concentration in water decreased 74% on day-7, 80% on day-14, 99% on day-28 and reach 100% on day-48 for treatment 10 mg/L. Pb concentration decreased 91% on day-7, 93% on day-14 and then on the day-28 the reduction reached 99% for treatment of 30 mg/L. For Pb treatment of 50 mg/L, the reduction reached 92% on day-7, 96% on day-14, and 99% on day-28. The sand adsorbed Pb up to 7.91×10-4 mg/kg for 10 mg/L, 1.07×10-3 mg/kg for 30 mg/L and 2.41×10-3 mg/kg for 50 mg/L. Pb uptake by plant was 2286 mg/kg on day-98, 4174 mg/L on day-28 and 8297 mg/kg on day-14 for 10, 30 and 50 mg/L, respectively. The highest Bioaccumulation Concentration (BC) was 10618 for 10 mg/L on day-28, 81311 for 30 mg/L and 81467 for 50 mg/L both on day-42, with the Translocation Factor (TF) related to the same day of these BC were 0.13, 0.24, and 0.35 respectively. The highest TF value for 10 mg/L were 0.7 on day-98, 0.38 for 30 mg/L on day-70 and 0.59 for 50 mg/L on day-14