Richard Buamah - Academia.edu (original) (raw)

Papers by Richard Buamah

Journal of Environmental Chemical Engineering, 2016

Abstract Studies conducted in the past have shown aluminum oxide coated bauxite (AOCB) and alumin... more Abstract Studies conducted in the past have shown aluminum oxide coated bauxite (AOCB) and aluminum oxide coated charcoal (AOCC) as versatile and potential fluoride adsorbents. This study focused on the feasibility of regenerating AOCB and AOCC by recoating and stabilizing the exhausted media. Using bench scale and short column experiments the adsorption capacities, kinetics and filter run times of the fluoride removal process were determined. The toxicity and leaching of the adsorbed fluoride from exhausted adsorbents were also investigated. Recoating of exhausted AOCC and AOCB in order to regenerate them was feasible empirically with three regeneration cycles. The fluoride adsorption capacities of the AOCC and AOCB were restored and even increased after the first episode of regeneration. The adsorption capacity of the AOCC was 1.5 times greater than that of the AOCB. In the column experiments AOCC1 and AOCB1 showcased longer filter run times. The aluminum oxide coated onto all exhausted media was stable and did not leach into solution.

Journal of Science and Technology (Ghana), 2016

The prevalence of high concentrations of fluoride (i.e. > 1.5 mg/l) in groundwater in the Norther... more The prevalence of high concentrations of fluoride (i.e. > 1.5 mg/l) in groundwater in the Northern part of Ghana especially around the Bongo communities has been an issue of concern. Owing to the arid nature of these localities, the inhabitants (who are mainly peasant farmers), rely more on groundwater sources for their drinking water. With the strenuous nature of their job and the warm weather conditions, the farmers generally consume more water, thus becoming more vulnerable to dental and skeletal fluorosis. This study focused on the removal of fluoride from groundwater by employing surfactant modified zeolites (SMZ) synthesized using locally available kaolin material as precursor. The zeolite synthesis involved calcination of kaolin, alkaline fusion and hydrothermal treatment. The final product was modified with 5g/L Hexadecyltrimethylammonium bromide (HDTMABr). The zeolite was characterised by Xray Diffraction (XRD), Energy Dispersive Xray (EDX) and Scanning Electron Microscopy (SEM) and the modified form employed in batch fluoride removal studies. The fluoride adsorption kinetics was studied using model water with varying initial fluoride concentration. From the EDX analysis, the synthesized zeolite NaLSX was found to comprise predominantly Oxygen (60%), Silicon (15%), and Aluminium (13%). The SEM showed the zeolite NaLSX crystals to be octahedrally shaped. The unmodified zeolite NaLSX was incapable of adsorbing fluoride ions but the surfactant modified zeolite adsorbed fluoride. The fluoride adsorption capacity of the modified zeolite was pH dependent and peaked at pH 6.0-7.0.

Water Supply, 2013

High fluoride levels beyond the recommended value of 1.5 mg/L have been detected in several groun... more High fluoride levels beyond the recommended value of 1.5 mg/L have been detected in several groundwater wells in Northern Ghana. This occurrence has led to the capping of many high yielding wells that hitherto have been major sources of drinking water for the populace in these arid areas. Most of the fluoride removal technologies applied in the area has not been versatile in effectively removing fluoride because of the varying water qualities. This study focused on screening adsorbents including high aluminium or iron containing bauxite ores, fabricated zeolite and activated Neem seeds for removal of fluoride from drinking water. The model water used was prepared by simulating the prevailing groundwater quality in Northern Ghana. The high aluminium bauxite ore (HABO) had the highest fluoride removal capacity. Within the pH range tested (5–7), the fluoride removal decreased with increasing pH. Occurrence of sulfate, chloride and nitrate in the model water reduced the fluoride removal...

Water Supply, 2009

Most drinking water production plants use rapid sand filters for the removal of manganese from gr... more Most drinking water production plants use rapid sand filters for the removal of manganese from groundwater. The start-up of manganese removal on newly installed sand media is slow, taking several weeks till months. Reducing this period in order to prevent the loss of water during this phase has become an issue of concern. In this study pilot and bench scale experiments were conducted to investigate the mechanism, influence of operational conditions (e.g. filtration rate, manganese loading) and measures that enhance manganese removal capacity of the sand media. Other filter media were investigated with the objective of finding suitable substitutes for the sand. The development of the adsorptive/catalytic coating the sand media in a pilot plant was very slow, notwithstanding the relatively high pH of 8. Low manganese concentration and more frequent backwashing resulted in a longer start up period of the manganese removal. It can not be excluded, that nitrite has a negative effect as w...

Water Science and Technology, 2009

For the removal of iron from groundwater, aeration followed with rapid (sand) filtration is frequ... more For the removal of iron from groundwater, aeration followed with rapid (sand) filtration is frequently applied. Iron removal in this process is achieved through oxidation of Fe2 + in aqueous solution followed by floc formation as well as adsorption of Fe2 + onto the filter media. The rate of oxidation of the adsorbed Fe2 + on the filter media plays an important role in this removal process. This study focuses on investigating the effect of pH on the rate of oxidation of adsorbed Fe2 + . Fe2 + has been adsorbed, under anoxic conditions, on iron oxide coated sand (IOCS) in a short filter column and subsequently oxidized by feeding the column with aerated water. Ferrous ions adsorbed at pH 5, 6, 7 and 8 demonstrated consumption of oxygen, when aerated water was fed into the column. The oxygen uptake at pH 7 and 8 was faster than at pH 5 and 6. However the difference was less pronounced than expected. The difference is attributed to the pH buffering effect of the IOCS. At feedwater ...

Water Practice & Technology, 2014

Chlorine is one of the many disinfectants used to ensure bacteriological safety of drinking water... more Chlorine is one of the many disinfectants used to ensure bacteriological safety of drinking water. Usually residual chlorine is maintained within the distribution network to combat any probable re-contamination of the distributed water. This residual free chlorine, however, decays in water due to its reaction with the bulk water and the pipe material or deposits on the pipe walls. This study aimed at determining and modelling chlorine decay in the Kumasi water distribution network (KWDN) and determined locations where residual chlorine boosting is necessary. A double-jacketed batch reactor and a constructed pilot distribution system (PDS) were used to determine the bulk and wall decay coefficients. The PDS was run using aged PVC pipes (15–20 years), asbestos concrete pipes (40–50 years) and cast iron pipes (84 years) that have been in use in the KWDN. The SynerGEE® hydraulic model was used to identify the ‘zero chlorine’ points and predict top-up quantities. The bulk decay coefficie...

The study aimed at assessing chlorine decay and its impact on water quality in the Kumasi Water D... more The study aimed at assessing chlorine decay and its impact on water quality in the Kumasi Water Distribution Network, the second largest in Ghana. A Pilot Distribution System (PDS) was constructed with three different pipe materials excavated from the existing network; PVC pipes (15 - 20 years), Asbestos Concrete pipes (A.C., 40 - 50 years) and Cast Iron pipes (C.I., 84 years). The PDS was run with model water with two (2) predetermined residual chlorine concentrations of 0.74 mgl/L and 1.44 mg/L. The loss in chlorine residual and the deterioration in water quality was assessed over a hydraulic retention time (HRT) of 24 hours. Under the conditions tested, the C.I. pipes consumed chlorine faster possibly due to large encrustation on the pipe walls thereby compromising bacteriological safety of the water. Chlorine loss in cast iron pipes was also associated with pH drop, increase in colour and turbidity at HRT ≥ 2 hours. For all pipes under test, microbial re-growth was observed afte...

Applied Water Science

A data-based multivariate method such as response surface methods and desirability function is co... more A data-based multivariate method such as response surface methods and desirability function is considered advantageous for analysing coagulation treatment optimization. Thus, this study investigated the optimization of coagulation–flocculation using response surface methodology. The parameters investigated were pH, alum dose and alkalinity. The optimum coagulation conditions for the individual responses: turbidity, colour, residual aluminium and phenanthrene were pH 7.0, alum dose 80.0 mg/L and alkalinity 80.0 mg/L; pH, 6.5, alum dose 70.0 mg/L and alkalinity 90.0 mg/L; pH, 7.0, alum dose 63.2 mg/L and alkalinity 80.0 mg/L and pH 6.2, alum dose 80.0 mg/L and alkalinity of 80.0 mg/L, respectively. The model equation derived from the optimization study was adequate for predicting the response values. The quadratic model was significant (p < 0.0001), and it had a high correlation (R2, 0.746–0.975) and an insignificant (LOF, p > 0.05) lack of fit.

Journal of Environmental and Public Health, Apr 30, 2019

Arabian Journal of Geosciences, 2021

High metal concentrations in water and soil solution result in greater plant uptake and/or leachi... more High metal concentrations in water and soil solution result in greater plant uptake and/or leaching of metals. The objective of this research was to ascertain the effects of variations in heavy metal concentrations on phytoremediation processes. Two macrophytes, Typha capensis and Heliconia psittacorum, were engaged in the remediation of arsenic, lead, mercury, and cadmium. The plants were dosed with varying concentrations of heavy metals. The plants were exposed to the investigation by inductive coupled plasma-mass spectroscopy (Agilent 7700 × arrangement ICP-MS produced for complex framework examination). The exposure of the heavy metals under varying concentrations of the heavy metals showed that the level of uptake by the macrophytes was dependent on the level of concentration available in the soil/water. This conclusion implicitly implies that the quantity of heavy to be absorbed by the macrophytes depends largely on the capacity of the macrophyte to absorb a particular kind of heavy metal.

American Journal of Environmental Sciences, 2018

The evaluation of the rate of heavy metal absorption by aquatic plants; Typha capensis and Helico... more The evaluation of the rate of heavy metal absorption by aquatic plants; Typha capensis and Heliconia psittacorum was carried out for the removal of Hg, As, Cd and Pb from water and soil. Uptake of Hg, As, Cd and Pb by these aquatic plant species in metal contaminated water and soil were studied in batch culture experiment. The plants were irrigated with standard heavy metal simulated solutions. After 10, 20, 30 and 40 days, plant samples were subjected to analysis by Inductive Coupled Plasma-mass Spectroscopy (Agilent 7700x series ICP-MS developed for complex matrix analysis). The rate of the heavy metal uptake by the T. capensis far exceeded that of the H. psittacorum in both the roots and shoots. Arsenic, cadmium and mercury showed considerable uptake by both macrophytes in the shoots than that of the roots; indicating the high absorption capacities of the three metals by the macrophytes. It was evident that arsenic, cadmium and mercury exhibited systematic rate of absorption by t...

International Journal of Energy and Water Resources, 2019

The new international rules led by the Library of Congress-Resource Description& Access are widel... more The new international rules led by the Library of Congress-Resource Description& Access are widely used worldwide. This rule applies to the description of all types of document resources that may or may not be available in the future, and the resource has more provisions, more specific provisions, and more content, and is used by multiple countries and OCLC (the world's largest library joint cataloging agency). The paper sorts out the characteristics and cataloging status of Chinese minority literature, and analyzes the advantages and difficulties of minority literature cataloging based on RDA rules.

Journal of Science and Technology (Ghana), 2015

Journal of Water Supply: Research and Technology-Aqua, 2008

Iron oxide coated sand (IOCS) is a potential adsorbent for metallic ions, e.g. arsenic, lead, man... more Iron oxide coated sand (IOCS) is a potential adsorbent for metallic ions, e.g. arsenic, lead, manganese etc., however the effect of process conditions and the mechanism of its adsorption of Mn(II) have not been thoroughly investigated. This study determined the capacity, rate, mechanisms involved and the effect of process conditions on the adsorption of Mn(II) onto IOCS using laboratory scale

Journal of Contaminant Hydrology, 2012

The presence of excess fluoride in groundwater in the Northern region of Ghana has resulted in th... more The presence of excess fluoride in groundwater in the Northern region of Ghana has resulted in the closure of many boreholes for drinking water supply to avoid the incidence of fluorosis and other related health effects. The fluoride concentration in 357 groundwater samples from the area ranged between 0.0 and 11.6mg/L, with a mean value of 1.13mg/L. Piper graphical classification, correlation coefficients, principal component analysis (PCA) and thermodynamic calculations were used as an approach to gain insight into the groundwater chemical composition and to help understand the dominant mechanisms influencing the occurrence of high fluoride waters. Spatial join procedure was used to examine the relationship between the underlying geology of the study area and fluoride distribution. Six groundwater types were identified for the area: Ca-Mg-HCO(3), Ca-Mg-SO(4), Na-Cl, Na-SO(4), Na-HCO(3) and mixed water type. PCA performed on the groundwater chemical data resulted in 4 principal components (PCs) explaining 72% of the data variance. The PCs represented the predominant processes controlling the groundwater chemistry in the study area which include; mineral dissolution reactions, ion exchange processes and evapotranspiration processes. PHREEQC calculations for saturation indices for the groundwater samples indicated they were largely saturated with respect to calcite and under-saturated with respect to fluorite, suggesting that dissolution of fluorite may be occurring in the areas where it is present. A review of the PCA results and an evaluation of the equilibrium state of the groundwater based on the saturation indices, suggest that some of the processes controlling the overall groundwater chemistry in the study area also influenced the fluoride enrichment. These predominant processes include the dissolution of the mineral fluorite, anion exchange processes (F(-)/OH(-)) involving clay minerals and evapotranspiration processes. Elevated fluoride levels in the study area were found to occur predominantly in the Saboba and Cheriponi districts and also in the Yendi, Nanumba North and South districts. These areas are underlain by the Middle Voltain formation (Obossom and Oti beds), comprising mainly of sandstone, limestone, conglomerate, shale, arkose and mudstone. Results of the hydrochemical analysis show that aside from the boreholes with elevated concentrations of fluoride (beyond 1.5mg/L), groundwater in the study area based on the parameters analyzed is generally chemically acceptable and suitable for domestic use.

Chemical Engineering Journal, 2013

h i g h l i g h t s Removal of excess fluoride in drinking water is important to protect public h... more h i g h l i g h t s Removal of excess fluoride in drinking water is important to protect public health. The search for suitable fluoride adsorbent continues to be of interest. Coating of pumice surfaces with aluminum for fluoride removal was found promising. Approach of study was based on the HSAB concept and on use of indigenous materials. Aluminum oxide coated pumice could be useful in countries where pumice is indigenous.