Biosand Filtration as a Green Approach to Septic Tank Effluent Management in a Tertiary Institution in Ghana

Sewage and household effluents at some institutions in Ghana have been discharged into the ocean for years. Thisdegrades environmental media and is detrimental to ecological systems. The Three Local Plastic Barrel-Biosand Filter (TLPB-BSF) is an innovation on the slow sand filter that has been used to prevent discharge of raw sewage into the environment. The study aimed to test the performance of a modified BSF on sewage tank effluent and assess suitability of the filtrate for non-drinking purposes at a tertiary institution renamed KOTU to maintain confidentiality. Method: A filtration system made of three modified interconnected BSF was constructed on-site, with last filter connected to a storage tank. The modification was the provision of an additional media (charcoal) in the second barrel. Two sample collections were made from the system one week apart. The pre-filtrate samples were raw septic tank effluent (STE) and the samples obtained after running system was Biosand filter effluent (BSFE). Samples were analysed for physical and microbiological parameters at designated laboratories. Measured values of the parameters in pre-filtrate and filtrate samples were compared with EPA (Ghana) reference values. The removal efficiency of a parameter was computed as the difference between pre-filtrate and filtrate values expressed as a percentage of the pre-filtrate value. Results: Most of the effluent parameters from the BSF were within the EPA standards, while others were unacceptable. Removal efficiencies obtained for the parameters were: Ni trogen (83.3%), Phosphorus (89.5%), Total Suspended Solids (71.3%), Total Dissolved Solids (66.2%), Total coliform (99.9%), Faecal coliform (99.7%) and E. coli (97.6%). Conclusion: BSF is effective for upgrading physical and microbial quality of sewage at household and institutional level, prior to discharge in the environment. It produced a filtrate that met most of EPA standards for irrigation of non-edible crops

Knowledge Levels of Extension Agents and their Perceived Impact of Climate Change on Extension Service Provision in Ghana

This study examined the knowledge levels of extension agents and their perceived impact of climate change on extension service provision in Ghana. Specifically, it examined awareness levels of agents on the causes, effects and methods for mitigating climate change. It also determined their perceived impact of climate on extension service delivery. A structured questionnaire was used to elicit information from a sample size of 192 respondents from 10 regions in Ghana who were randomly selected. The data were analyzed using frequency, percentages, mean, and standard deviation. Data was further analysed qualitatively by content analysis given the prevalent use of Likert type scale analyses. The findings showed that majority of the respondents were males within the age range of 40 to 49 years, married with above 15years work experience in extension service provision. They possessed high awareness of the concept - climate change, and need for farmers to be exposed to new technology. The study concluded that extension workers have to be abreast of innovations in agriculture and there is a need for incorporation of meteorological information in extension messages to farmers. It was recommended that extension agents should embrace a more innovative and participatory approaches of providing services

Book Reviews

This issue of the CJAS includes reviews of two important books: The Mind of Africa by William Abraham, that was recently re-issued in paperback, and Building the Nation: Seven Notable Ghanaians, edited by Mercy Akrofi- Ansah and Esi Sutherland-Addy. We think that these commentaries provide critical illumation of these important texts, and we are grateful to Professor Emeritus Ivan Addae-Mensah, and Drs Amoah-Boampong and Richmond Kwesi for their thoughtful reflections

Understanding Lateritic Ore Agglomeration Behaviour as a Precursor to Enhanced Heap Leaching

Although nickel (Ni) laterite ores constitute the majority of Ni mineralization resource world-wide, in contrast to Ni sulphides, their processing via conventional beneficiation (e.g. multi-gravity and flotation) and hydrometallurgical routes is intractable as they are predominantly low grade and complex, both mineralogically and chemically. Due to their physico-chemical character-istics, low grade lateritic ores require more aggressive but costly chemical and hydrometallurgical techniques (e.g., leaching in high pressurized tanks) for value metal (Ni and Co) extraction. Processing such ores through cost-competitive heap (4-10 m high) leaching as an alternative, requires successful agglomeration of the feed into robust and porous granules. To date, produc-ing of granules with desirable attributes poses a major geotechnical challenge to industry. In the present work, we investigate agglomeration behaviour of siliceous goethite Ni laterite ore and selected oxides and clay minerals (hematite, quartz and kao-linite) which constitute the predominant host gangue phases of typical low grade Ni laterite ores. Fundamental knowledge and understanding of the agglomeration mechanisms and kinetics which are essential for producing robust real ore granules, and pivotal to the subsequent heap leaching process, are gleaned. Isothermal, batch agglomeration tests involving 30 and 44 % w/w sulphuric acid solution as a binder indicated that 5 – 40 mm granules of differing roughness and morphologies were produced in 8-14 min. The results showed feed characteristics (e.g., mineralogy and particle size distribution) and binder content (15-25 wt.%) dependent agglomeration behaviour. Slow agglomerate nucleation and growth were displayed by the kaolinite clay min-eral whilst the oxides exhibited faster agglomeration kinetics. Siliceous goethite feed ore fine/coarse ratio, H2SO4 binder dosage and acid content, product drying temperature and aging conditions, all showed significant impact on agglomeration mecha-nisms (e.g., particle wetting, nucleation and growth processes) and granule attributes (e.g., size and strength). Agglomerates strength increased with increasing fine/coarse particle ratio

Operational Risk Management Systems Implementation in Ghanaian Banks: The Critical Success Factors

This quantitative study investigates the critical success factors for effective implementation of operational risk management systems in Ghanaian banks. A validated survey instrument was used in the data collection across 30 commercial banks in Accra. Factor analysis was deployed to extract the most critical success factors in testing all eight hypotheses. The Pearson correlation result reveals that independent variables: Risk Governance, Risk Management Policy, Risk Management Planning, Customized Risk Management Process, Risk management Implementation, Risk Management Training, Risk-based Performance Appraisal and Risk Management Culture were positively and statistically significant with effective ORMS implementation in Ghanaian banks. Hence, the eight independent variables were identified as critical success factors for effective ORMS Implementation in Ghanaian banks. The study recommends that top management should invest into the development of comprehensive risk management plans and policies, and to integrate these policies into the overall strategic risk culture for an effective ORMS implementation in their banks. The study made other key recommendations

Hispidulin And Other Constituents Of Scoparia dulcis Linn

Phytochemical investigation of the ethanol extract of the whole plant of Scoparia dulcis, has resulted in the isolation of 4, 5, 7-trihydroxy-6-methoxyflavone, commonly called hispidulin and a steroidal glycoside, β-sitosterol-β-D-glucoside.  This is the first isolation of the two compounds from S. dulcis. Also isolated and characterized were the previously reported 6-me-thoxybenzoxazolinone, friedelan-3-one and scopadulcic acid B. Structural elucidation was done on the basis of spectroscopic data interpretations (IR, UV, NMR and EIMS).  Using the Tetrazolium-based colorimetric selective assay, hispidulin was found to be inactive against HIV-1/IIIB in MT-4 cells whereas the same test on the aqueous extract of the plant was positive

Parasitoid complex of fall armyworm, spodoptera frugiperda, in Ghana and Benin

Open Access Journal; Published online: 21 Jan 2020The fall armyworm, Spodoptera frugiperda, a moth originating from the American continent, has recently invaded most African countries, where it is seriously threatening food security as a pest of cereals. The current management methods rely heavily on the use of synthetic insecticides but there is a need for more sustainable control methods, including biological control. Surveys were conducted in two West African countries, Ghana and Benin, to determine the native parasitoid complex and assess parasitism rates of S. frugiperda. Samples of S. frugiperda eggs and larvae were collected in maize fields located in 56 and 90 localities of Ghana and Benin, respectively, from July 2018 to July 2019. Ten species were found parasitizing the pest, including two egg parasitoids, one egg–larval, five larval and two larval–pupal parasitoids. The two most abundant parasitoids in both countries were two Braconidae: the egg‐larval parasitoid Chelonus bifoveolatus and the larval parasitoid Coccygidum luteum. Parasitism rates were determined in three Ghanaian regions and averages varied from 0% to 75% between sites and from 5% to 38% between regions. These data provide an important baseline for the development of various biological control options. The two egg parasitoids, Telenomus remus and Trichogramma sp. can be used in augmentative biological control and investigations should be conducted to assess how cultural practices can enhance the action of the main parasitoids, C. luteum and Ch. bifoveolatus, in the field. Understanding the parasitoid complex of S. frugiperda in Africa is also necessary before any development of classical biological controls involving the introduction of parasitoids from the Americas

Modeling Memorization and Forgetfulness Using Differential Equations

{\bf Research Context}: The aim of the study was to use differential equations to model memorization of students based on a given data taking into account forgetfulness.\\\noindent {\bf Research Methods}: The purpose of this paper was to decipher the rate at which students memorized the stuff that required memorization in the area of axioms and proofs of theorems as well as considering the fact that they will forget some of them along the way. The usage of differential equation was employed to model the trend. The paper contributes to the literature by documenting that students can memorize large number of stuff even beyond their perceived imaginations.\\\noindent {\bf Conclusion}:  This study employed the usage of differential equations to model the rate at which students could memorize a given number of axioms and proofs, considering the fact that they will forget some of them along the way. Persons who are able to absorb and retain more are able to recollect better than those who can absorb more and retain less.  On the other hand, those who can absorb less and retain more have an upper hand in recollection over those who can absorb more and retain less. Consequently it is better to have a higher retention constant than a higher absorption rate. Factors like the learning strategy, learning materials, learning environment, study mates have either a positive or negative influence on an individual's absorption and retention in the long term