Carbothermal Upgrading of the Awaso Bauxite Ore using Sawdust and Coconut Shells as Reductant

Ghana’s bauxite is exported in the raw state with no value addition. One way to achieve value addition is to carbothermally upgrade the ore into magnetic and nonmagnetic fractions, followed by separation using a magnet. This work investigates the carbothermal upgrading of the Awaso bauxite ore using reductant generated from locally available saw dust (SD) and coconut shells (CNS). Composite pellets of bauxite-reductant were prepared, air-dried and cured for 72 hours. The cured pellets were placed in a fire-clay crucible and heated in a custom-made gas-fired furnace for 30 minutes. The fired composite pellets were separated into magnetic and non-magnetic portions using a low intensity hand-held magnet. The various portions were then characterised using XRD, XRF and SEM analyses. XRD results showed magnetite as the predominant species present in the magnetic fraction whilst the non-magnetic fraction showed alumina as the predominant peaks along with some traces of unreduced hematite, silica, carbon and titania but no hercynite.  Keywords: Bauxite, Palm Nut Shells, Gas-Fired Furnace, Hercynite, Cha

Precipitable Water Comparisons Over Ghana using PPP Techniques and Reanalysis Data

Atmospheric Water vapor is an important greenhouse gas and contributes greatly in maintaining the Earth’s energy balance. This critical meteorological parameter is not being sensed by any of the 22 synoptic weather stations in Ghana. This study presents a highly precise tool for water vapor sensing based on the concept Global Navigation Satellite Systems (GNSS) meteorology and tests the computed results against global reanalysis data. Conventional approaches used to sense the atmospheric water vapor or Precipitable Water (PW) such as radiosondes, hygrometers, microwave radiometers or sun photometers are expensive and have coverage and temporal limitations. Whereas GNSS meteorological concept offers an easier, inexpensive and all-weather technique to retrieve PW or Integrated Water Vapor (IWV) from zenith tropospheric delays (ZTD) over a reference station. This study employed precise point positioning (PPP) techniques to quantify the extend of delays on the signal due to the troposphere and stratosphere where atmospheric water vapor resides. Stringent processing criteria were set using an elevation cut-off of 5 degrees, precise orbital and clock products were used as well as nominal tropospheric corrections and mapping functions implemented. The delays which are originally slanted are mapped unto the zenith direction and integrated with surface meteorological parameters to retrieve PW or IWV. The gLAB software, Canadian Spatial Reference System (CSRS) and Automatic Precise Positioning Service (APPS) online PPP services were the approaches used to compute ZTD. PW values obtained were compared with Japanese Metro Agency Reanalysis (JRA), European Centre for Medium-Range Weather Forecasts Reanalysis (ERA-interim) and National Center for Environmental Prediction (NCEP) global reanalysis data. Correlation analysis were run on the logged station data using the three approaches and global reanalysis data. The obtained results show stronger correlation between the retrieved PW values and those provided by the ERA-interim. Finally, the study results indicate that with a more densified network of GNSS base stations the retrieved PW or IWV will greatly improve numerical weather predictions in Ghana.Keywords: GNSS Signals, PPP, Integrated Water vapour, Precipitable Water, Reanalysis Model

Institutions and Poverty: A Critical Comment Based on Evolving Currents and Debates

Tebaldi & Mohan (2010, JDS) have established an empirical nexus between institutions and monetary poverty. We first, reflect their findings in light of recent development models, debates and currents in post-2010 literature. We then re-examine their results with a non-monetary and multidimensional poverty indicator first published in 2010. Our findings confirm the negative relationship and the nexus disappears with control for average income. Hence, confirming the conclusions of the underlying study that institutions could have an indirect effect on multidimensional poverty. In other words, the poverty eradication effect of institutions is through income-average as opposed to income-inequality. We discuss the confirmed findings in light of implications to: (1) debates over preferences in economic rights; (2) China’s development/outlook; (3) the Chinese model versus sustainable development; (4) the Fosu conjectures; (5) Piketty’s & Kuznets’ celebrated literatures and (6) future research to ascertain the inequality mechanism

Evaluation of Windsond S1H2 performance in Kumasi during the 2016 DACCIWA field campaign

Sparv Embedded, Sweden (http://windsond.com, last access: 22 February 2019), has answered the call for less expensive but accurate reusable radiosondes by producing a reusable sonde primarily intended for boundary-layer observations collection: the Windsond S1H2. To evaluate the performance of the S1H2, in-flight comparisons between the Vaisala RS41-SG and Windsond S1H2 were performed during the Dynamics–Aerosol–Chemistry–Cloud Interactions in West Africa (DACCIWA) project (FP7/2007–2013) ground campaign at the Kumasi Agromet supersite (6∘40′45.76′′&thinsp;N, 1∘33′36.50′′&thinsp;W) inside the Kwame Nkrumah University of Science and Technology (KNUST), Ghana, campus. The results suggest a good correlation between the RS41-SG and S1H2 data, the main difference lying in the GPS signal processing and the humidity response time at cloud top. Reproducibility tests show that there is no major performance degradation arising from S1H2 sonde reuse.</p

Assessment of Heavy Metal Contamination and Distribution in Surface Soils and Plants along the West Coast of Ghana

Onshore oil drilling activity is ongoing at Jubilee oil fields, Ghana. This activity could lead to heavy metal exposure with consequential adverse effects on public health in nearby coastal communities. Therefore, we assessed heavy metal levels and spatial distribution in soils and plants from the west coast of Ghana to obtain baseline values for monitoring heavy metal exposure. Surface soils were collected from six coastal communities, and analyzed for arsenic, cadmium, copper, mercury, lead, selenium and zinc using atomic absorption spectrophotometer. Mean heavy metal concentrations in soil samples were 2.06, 6.55, 0.016, 21.59, 0.18 and 39.49mg/kg for arsenic, copper, mercury, lead, selenium and zinc, respectively. Mean heavy metal concentrations in plants were 2.70, 17.47, 3.17, 91.74, 1.51 and 9.88mg/kg for arsenic, cadmium, copper, lead, selenium and zinc, respectively. Concentrations of arsenic, cadmium and lead in plants exceeded WHO/FAO permissible limits. Enrichment factor for arsenic was significant and extremely high for selenium, while geoaccumulation index showed moderate pollution for selenium. Soil contamination factors for arsenic, lead, and selenium indicated considerable contamination. In view of these findings remediation methods must be adopted to safeguard the communities. The data will be useful for future monitoring of heavy metal exposure in the communities and to assess the impact of the ongoing crude oil drilling activity on the environment

On the Empirics of Institutions and Quality of Growth: Evidence for Developing Countries

We explore a newly available dataset on quality of growth to investigate the effect of institutions on growth quality in 93 developing countries for the period 1990 to 2011. Quality of institutions is measured in term of political risk. The empirical evidence is based on: (i) Ordinary Least Squares (OLS) and Two Stage Least Squares (2SLS) and (ii) cross-sectional and panel data structures. In order to avail room for more policy implications, the dataset is further disaggregated into income levels, namely: Lower middle income (LMIC), low income (LI) and upper middle income (UMIC). Three main findings are established. First, institutions are positively related to the quality of growth. Second, institutions have significantly contributed to growth quality in increasing order during the following time intervals: 2005-2011, 1995-1999 and 2000-2004. Third, the positive nexus between institutions and growth quality is fundamentally driven by LMIC. Policy implications are discussed