1,720,958 research outputs found
Water consumption and wastewater generation from small-scale crude palm oil extraction in Ghana
Full text linkCrude palm oil extraction is one of the sources of livelihood in Ghana’s Central Region. However, the water use and wastewater generation associated with the industry have not been given adequate attention. This study assessed the water consumption and wastewater generation by small-scale crude palm oil extraction mills in the region. Twenty-five (25) mills were selected from four palm oil-processing local government areas in the region. An interview guide was used to obtain information about the operations of the mills and corroborated through structured observations. Water consumption and wastewater generation were measured using a graduated plastic bucket. Water for processing was found to be sourced from hand-dug wells (56%), treated piped water (20%), boreholes with handpumps (16%) and rivers (8%). Water was bought at US2.89 (piped water) per cubic metre. The recurrent cost of water was the same as that paid for domestic use. For a litre of palm oil produced, 0.760-2.391 litres of water were consumed and 68-82% returned as wastewater. Sixty-eight percent of the water was used for boiling. The distance to water source influenced the consumption, with higher water consumption recorded for mills with on-plot water sources. Higher recurrent costs of water did not necessarily lead to lower water consumption. There was no significant difference in the water consumption and wastewater production between the wet and dry processing methods. The small-scale palm oil processing industry requires attention to manage a potential competition between commer-cial and domestic water use in rural and small towns
Application of Palm Kernel Shell Granular Filter Medium for Decolourisation and COD Removal from Clarified Palm Oil Mill Effluent
Full text linkPalm oil mill effluent (POME) is characterised by high colour, COD and solids. Extraction and drying of the suspended solids for reuse as solid fuel shows great promise. However, the clarified wastewater may require further treatment to meet discharge limits. This study was aimed at evaluating the efficiency and kinetics of COD and colour removal from clarified POME using palm kernel shell (PKS) granular filter media and a sand filter as reference. The wastewater was collected from a small-scale palm oil processing mill in the Abura Aseibu Kwamankese District of Ghana and clarified using a solid-liquid separation system. The filter media of particle size 1.18mm was packed into acrylic cylinders (6cm dia.) to a height of 35.4 cm. The characteristics of influent wastewater and filter media were determined prior to the experiment following standard methods. Each filter was run as a batch system under anaerobic conditions by maintaining a minimum supernatant height of 10cm. Effluents were drawn from the bottom of each filter after 0, 24, 48, 72, 96, and 120 h for analysis using standard analytical methods. The removal efficiencies for the PKS and sand filters were, respectively, 77% and 79% for COD and 69% and 62% for colour. The COD removal was consistent with first-order kinetics for both PKS and sand filters. However, colour removal in PKS and sand filters followed second- and zero-order kinetics respectively. The correlation coefficients of the selected kinetic models show a strong correlation between the experimental and predicted results. Further research is required to establish the retention time required to bring the pollutant levels below the allowable limits for discharge into the environment
Qualitative Assessment of Palm Oil Mill Wastewater from Small-Scale Processing Mills in Ghana
No full textPalm oil production in Ghana is dominated by informal small-scale mills that produces about 80% of the national production. These mills have been noted for violating environmental regulations. This research was aimed at characterizing palm oil mill wastewater produced by small-scale mills in Ghana to better understand the extent of environmental damage. Four processing mills were selected from Abura Aseibu Kwamankese District of Ghana. Wastewater samples were collected from each of the four processing mills in March 2020 (peak production season). Samples were collected in opaque plastic containers and stored under 4 °C. Parameters measured were pH, total solids, TSS, TDS, BOD5, COD, total nitrogen, phosphorus, potassium and oil and grease using standard analytical methods. The mean characteristics of the wastewater were pH (4.5 ± 0.05), total solids (3,976 ± 1,397 mg/l), TSS (3,976 ± 1,397 mg/l), TDS (358 ± 158 mg/l), BOD5 (21,877 ± 4,728 mg/l), COD (56,357 ± 3,441 mg/l), COD:BOD5 (2.6), total nitrogen (246 ± 86 mg/l), phosphorus (60 ± 16 mg/l), potassium (156 ± 24 mg/l), and oil & grease (527 ± 198 mg/l). The mean concentrations of 6 out of the 7 parameters were over 2-orders of magnitude higher than the Ghana effluent discharge standard. The pH, TDS, BOD5 and COD of the wastewater from boiling were higher than for clarification. The current practice of disposing raw wastewater into the natural environment by the small-scale processing mills is negatively affecting the environment
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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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