Sustainable wastewater management:exploring the option of greywater reuse in a developing country – Ghana

The research explored greywater reuse strategies in a developing country. Quality and quantity estimation of greywater was assessed which established the detrimental effect of unregulated discharge of greywater into the environment. The study experimented the use of a locally produced adsorbent in reducing targeted contaminants in greywater and further studied associated behaviour relating to users. The local material was successful in reducing the targeted pollutant to the recommended guideline values. The study also established that, preference for greywater reuse was more geared toward non-potable uses. The research concludes that to convince household heads to adopt greywater treatment and reuse systems, specific drivers of intentions must be addressed in the campaign

Rainwater harvesting potential of University of Cape Coast campus: a GIS approach

This study accesses the potential of rainwater harvesting as an alternative to conventional water supply scheme in University of Cape Coast. The study involves estimating the surface area of rooftops on the University of Cape Coast campus by using Geographical Information System (GIS), obtaining the mean annual rainfall from the meteorological survey department and determining the quantity of rainwater that can be harvested on UCC campus. Satellite imagery of the whole campus is obtained with Google Earth. Thematic Maps are generated for 2008 to 2012. The volume of rainwater is then calculated for each year. From the calculation, it is realized that an average volume of 178,441m3 of rainwater can be harvested each year. The average water demand of the university during peak seasons is estimated to be 548.1m3 per day. This implies that, the rainwater can serve the University for about 325 days

Influence of mineralogy on upgrading of Polish copper ores

Upgrading curves play a significant role in the visualization and analysis of mineral separation results. Analysis of any separation from the upgrading point of view takes into account certain basic components such as the yield and content. Since these components can be combined into an unlimited number of new parameters, there are many upgrading curves. Each curve has its own unique way of analysing separation results. However, all these curves are generated from separation results without considering the influence of mineralogy on them. The thesis centres on the influence of mineralogy on the upgrading of Polish copper ore. The literature part of this thesis reviewed the theory of upgrading and separation curves. Many upgrading curves and their characteristics are described. Chemometric analysis and their application are also discussed in the literature part and mathematical equations for the upgrading of separation results reviewed. The data used for this thesis was obtained from three mineral processing plants in Poland and included data on flotation results, mineralogy results and litho logical layer percentages. Geological samples were taken from different mining areas of the processing plant with sandstone, shale and dolomite as the lithological layers. Fuerstenau and Halbich upgrading curves are used for the approximation and determination of upper maximum practical copper content respectively. Fuerstenau upgrading curves are drawn for the flotation results. These curves were approximated with a characteristic equation into a single parameter which characters the whole upgrading curve. This parameter was changed into a parameter F on the Fuerstenau upgrading curve through an equation. The maximum practical copper content (MPC) in the concentrate was obtained by using the Halbich upgrading curve. Maximum theoretical copper content (MTC) was determined through calculation from the mineralogical results. A calibration curve was developed which correlates maximum practical content and upper maximum theoretical content. Chemometric analyses between the copper content, the flotation parameter and mineralogical results were conducted to identify the influence of minerals on flotation and copper content in the concentrate. The same analysis was conducted on the flotation parameter and the lithological layer results. The results of the experiments showed that galena and pyrite are detrimental to the flotation of copper while the presence of bornite enhanced the copper content in the concentrate. Lithological chemometric analysis showed shale as responding poorly to flotation. The calibration curve which was developed can aid in forecasting and predicting the copper content in the concentrate by conducting mineralogical analysis. This curve is, however case specific and cannot be applied to other ores with different mineralogical characteristics

Extraction and Characterisation of African Star Apple (Chrysophyllum albidum) Seed Oil and the Adsorptive Properties of the Fruit Shell in Ghana

This research work was undertaken to determine the physicochemical parameters of oil from the seeds of African Star Apple (Chrysophyllum albidum) and further evaluate the adsorptive properties of the fruit shell. The oil was extracted using hexane with the soxhlet apparatus at a temperature of 65°C for 4 hours. The results showed an average oil yield obtained of 11.6%, specific gravity of 0.92kg/m3, the refractive index of 1.464 at 30°C, an acid value of 7.72 mg KOH/g, a free fatty acid value of 3.16 g/100g, saponification value of 200.56 mg KOH/g, and an iodine value of 70.64 g/100g. A Fourier Transform Infrared (FTIR) study on the oil identified some triglycerides, carbonyl, alkane, and alkene compounds. Adsorptive studies of the fruit shell for the removal of dye were also performed after chemical activation with CaCl2, MgCl2, and ZnCl2. The kinetics of the adsorption favoured a pseudo-first-order reaction pathway for CaCl2 with R2 of 0.941 while ZnCl2 and MgCl2 favoured a pseudo-second-order reaction pathway with R2 of 0.914 and 0.973, respectively

Greywater Characteristics, Treatment Systems, Reuse Strategies and User Perception-a Review

This paper presents a literature review of the quality of greywater generated in different, especially developing, countries, constituents found in greywater, some treatment systems, natural materials for treatment, some reuse strategies and public perception regarding greywater reuse. The review shows that generation rates are mostly influenced by lifestyle, types of fixtures used and climatic conditions. Contaminants found in greywater are largely associated with the type of detergent used and influenced by other household practices. Many of the treatment systems reviewed were unable to provide total treatment as each system has its unique strength in removing a group of targeted pollutants. The review revealed that some naturally occurring materials such as Moringa oleifera, sawdust, can be used to remove targeted pollutants in greywater. The study further showed that user perceptions towards greywater treatment and reuse were only favourable towards non-potable purposes, mostly due to perceived contamination or lack of trust in the level of treatment offered by the treatment system

Predicting greywater reuse for potable and nonpotable purposes in a developing country - a theory of planned behaviour approach

This study was aimed at predicting greywater reuse in a municipality of a developing country using the theory of planned behaviour (TPB). It sought to identify the beliefs that influence people's intentions to reuse greywater for potable and nonpotable purposes. Residents within the municipality completed a questionnaire designed with the TPB constructs and other demographic data. Results revealed an excellent fit for potable reuse intention and a mediocre fit for nonpotable reuse intentions. Attitudes and behavioural control were the constructs that significantly influenced intentions to reuse greywater for both potable and nonpotable purposes. Location of the source of water to the respondents and level of education were introduced as background factors. Location of the source of water had no significant direct or indirect influence on intentions to reuse greywater for potable or nonpotable purposes. Level of education had a nonsignificant indirect and direct effect on intentions to reuse greywater for potable purpose but is mediated through attitudes and perceived behavioural control for nonpotable reuse intentions. Strategies aimed at promoting greywater reuse should be targeted at a specific reuse option and not a wholesale intervention that is expected to address all reuse interventions.</p

Synthesis and Characterization of Modified Kaolin-Bentonite Composites for Enhanced Fluoride Removal from Drinking Water

Fluoride-contaminated drinking waters are known to cause severe health hazards such as fluorosis and arthritis. This paper presents the encapsulation of iron oxide nanoparticles in kaolin-bentonite composites adsorbents (KBNPs) for the removal of fluoride from drinking water by adsorption compared with kaolin-bentonite composite (KB). Adsorbents with an average weight of ∼200 mg and ∼7 mm diameter (granules) were prepared in the ratio of 10 : 10 : 0.1 for kaolinite, bentonite, and magnetite nanoparticles, respectively. The granules were air-dried and calcined at 750°C and contacted with 2 mg/L sodium fluoride solution at varying time periods. The adsorbents were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) formulation, and Brunauer–Emmett–Teller (BET), whereas the adsorption mechanism and the kinetics were explained using the Langmuir isotherm, Freundlich models, and pseudo-first-order and pseudo-second-order models. The results showed that the BET surface areas for the granules were 10 m2/g and 3 m2/g for KBNPs and KB, respectively. The SEM images for the adsorbents before and after adsorption confirm the plate-like morphology of kaolin and bentonite. The FTIR analyses of bentonite (3550 cm−1–4000 cm−1) and kaolin (400–1200 cm−1) correspond to the structural hydroxyl groups and water molecules in the interlayer space of bentonites and the vibrational modes of SiO4 tetrahedron of kaolin, respectively. The KBNPs composites also recorded a fluoride removal efficiency of ∼91% after 120 minutes compared with 64% for KB composites without Fe3O4 nanoparticles. The adsorptions of fluoride by the KBNPs and KB granules were found to agree with the Freundlich isotherm and a pseudo-second-order kinetic model, respectively. The results clearly show that the impregnation of clays with magnetite nanoparticles has significant effect in the removal of fluoride, and the implication of the results has been discussed to show the impact of clay-magnetite nanoparticles composites in the removal of fluoride from contaminated water