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Treatment of palm oil mill effluent using sandwich ultrafiltration technique
Get PDFNowadays, the treatment of palm oil mill effluent (POME) has become a major critical issue in Malaysia that needs to be highlighted. This is due to the extreme organic matter in POME that needs to be treated properly to tackle the environmental issue. POME is a thick brownish viscous liquid waste with an unpleasant odour, and high in colloidal suspension and organic matter. With the needs to solve the problems in terms of environmental protection, economical viability, and sustainable development, a recent innovative ultrafiltration technique using multiple membranes known as “sandwiches membrane”, has been extended for POME treatment. This work was carried out to evaluate the potential of pre-treatment methods (adsorption-settling-surface filtration) prior to ultrafiltration treatment and to investigate the potential of ultrafiltration membrane using single and sandwich configurations to reclaim clear water in the POME. This work is divided into two parts which are: (1) pre-treatment stage prior to ultrafultration membrane and (2) POME treatment using sandwich membranes. For the pre-treatment of POME prior to ultrafiltration there were two stages involved; adsorption with settling treatment and surface filtration. In the first stage, the combined effects for adsorption with settling experimental conditions such as adsorbent dosage, treatment time and stirring speed in one hour settling time were investigated. The performance of the adsorption and settling stage using palm kernel shell-based activated carbon (PKS-AC) was based on the analysis of the suspended solid. The supernatant was then pipette out and subjected to simple surface filtration, under vacuum through Whatman® qualitative filter paper, Grade 4 (20-25 μm) and finally to Whatman® qualitative filter paper, Grade 3 (6 μm) before proceeding to the ultrafiltration process. For ultrafiltration membrane treatment, dead-end filtration mode was used. Two 5 kDa flat sheets regenerated cellulose (RC) ultrafiltration membranes were sandwiched together in various orientations without any spacer in between. The effect of operating pressure, stirring speed and pH on the permeate flux and qualities namely total solid, dissolved solid, suspended solid,biological oxygen demand (BOD5), chemical oxygen demand (COD),and turbidity were also investigated. The pollutant concentration percentage reduction for the first stage of pre-treatment using 0.20g/L of PKS-AC at 39.82 rpm stirring speed in 35.94 min and 60 min of sedimentation time of POME showed a significant reduction in term of total solid (67.30%), dissolved solid (47.11%), suspended solid (71.26%), BOD5 (63.23%), COD (42.38%) and turbidity (63.31%) respectively. In the second stage of pre-treatment, the pollutant concentration was further reduced to 65.36%, 48.75%, 87.57%, 84.5%,48.9% and 78.9% for total solid, dissolved solid, suspended solid, BOD5,COD and turbidity respectively. After the pre-treatment stage, the membrane technique was applied with purpose to further reduce the pollutant concentration and reclaiming the crystal clear water that complied with WHO water reuse standard. Result for single membrane was compared to those of sandwich with various configurations. Interestingly, SB-sandwich configuration with bottom membrane in the reverse orientation significantly reduced almost 99% of pollutant in raw POME. The best conditions using SB-sandwich was achieved at pH 8,600 rpm of stirring speed and by applying 2 bar of operating pressure for 90 min of operating time with 47.24 L/m2h of permeate flux. Applying these conditions successfully reclaimed clear water with low concentration of total solid (138 mg/L), dissolved solid (123 mg/L),suspended solid (15 mg/L), BOD5 (90 mg/L), COD (113.3 mg/L) and turbidity (0.8 NTU) from POME. Moreover, by comparing between the single and SB-sandwich membrane, showed some differences in pollutant reduction: total solid (11.45%), dissolve solid (0.28%),suspended solid (53.85%), BOD5 (60%), COD (14.12%) and turbidity (70.12%). Hence, by applying the combination technique of adsorptionsettling- surface filtration (pre-treatment) with sandwich membrane ultrafiltration technique successfully treat POME and reclaim crystal clear water that complied with WHO water reuse standard
Effect of regenerated cellulose of ultrafiltration membranes on POME treatment
No full textPalm oil mill effluent (POME) in palm oil industry has become a big issue of environmental pollution to be solved urgently and critically. This wastewater consists of water, oil, and natural sediments. Hence, in this study, the work was carried out to investigate ultrafiltration process feasibility for treating palm oil mill effluent. Palm kernel shell bioactivated carbon (PKS-AC) adsorbent was used in adsorption treatment (pre-treatment) was used to reduced solid particles in POME. For adsorption treatment, POME was stirred with 0.20 g/L of PKS-AC at 39.94 minute and sediment for one hour. Membrane separation was subsequently applied to further treat the pre-treated POME. In this study, the permeate flux was found to be dependent to pressure applied, solution pH and stirring speed. An optium conditions was achieved at pressure 2 bar, with solution pH 8 using stirring speed 600 rpm. Considerable amount of POME pollutant is also reduced by used membrane for TS, DS, SS, BOD5, COD and turbidity were 625.32 mg/L, 445.32 mg/L, 180 mg/L, 1296 mg/L, 541.76 mg/L, and 16.20 NTU respectively. Thus, this result show that the pollutant in POME was reduced significantly using this technique
Turbidity and suspended solid reduction from palm oil mill effluent using coconut shell charcoal
No full textAn attempt was made to the changes of turbidity and suspended solid of palm oil mill effluent (POME) using activated biocarbon (bio-char) made up from coconut shell. The complete study was done in batch mode to investigate the effect of various operating parameters. The effect of treatment time, adsorbent dosage, agitation speed and pH was significantly effect on the turbidity and suspended solid in POME. Using 0.5 g of coconut shell charcoal (CSC)/100 ml at pH 4.2 with 90 rpm agitation speed in 10 minute the turbidity and suspended solid was reduced up to 84.3 % and 86.7% respectively. As a huge reduction of turbidity and suspended solid in POME, it could be a lucrative technique for treatment of domestic wastewater generated in palm oil sectors
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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