Issue 3

Water quality of Edion and Omodo Rivers were assessed chemically from March to October, 2010. The abstracted water samples were also subjected to bacteriological examination. The Rivers were each sampled at upstream and downstream locations. Twenty (20) physico-chemical characteristics which included heavy metals were determined in the laboratory. Air temperature ranged from the mean 30.69 to 31.38 °C, water temperature 26.50 to 27.00 °C, pH 7.05 to 7.15, electrical conductivity 7.99 to 25.55mScm^-1, turbidity 24.11 to 54.65FTU, total dissolved solids 6.14 to 7.78mgl^-1, total hardness 25.10 to 30.38mgl^-1, chlorine 22.06 to 25.02mgl^-1, BOD₅ 0.88 to 2.42mgl^-1, DO 3.81 to 6.50mgl^-1 and the nutrient elements such as  sulphate,  phosphate and Nitrate ranged between 0.03 and 3.81mgl^-1, sodium 1.87 to 3.81mgl^-1 and potassium 1.08 to 1.27mgl^-1. Heavy metals levels were low, ranging from 0.0025 to 5.6650mgl^-1 (Copper 0.0350 to 0.0910mgl^-1, Iron 0.2825 to 0.5112mgl^-1, cadmium 0.0015 to 0.0104mgl^-1, lead 0.0025 to 0.0230mgl^-1, zinc 2.7013 to 5.6650mgl^-1 and chromium 0.0025 to 0.0263mgl^-1). Conductivity, sulphate, zinc and fecal coliform count showed significant difference (P<0.05) with low values indicating good water quality. Water Quality Index (WQI) revealed that Stations 2 and 4 respectively had good water quality. All the characteristics had their values within FEPA Limit except for Zn (> 3.0mgl^-1).

The idea of wastewater application on soils, returned to Western Hemisphere during 1950-60. Modern living requires an increased per capita use of water for coverage of individual needs. Nowadays, two main principles related to water management seem to gain the attention of both the scientific communities and the stakeholders: 1.water saving in irrigation of agricultural crops without the reduction of food production, and 2. water saving during human use and industrial activity can only be promoted through water recycling. The increasing water demands at the level of Mediterranean countries are continuously intensified, because of the influence of a number of factors such as agricultural use and industrial consumption. The reuse of municipal wastewater in Mediterranean countries is now considered a useful practice. Countries such as Cyprus, Israel, Italy, Spain, France, Egypt, Tunisia, Morocco, and Greece, reuse the treated wastewater to a greater or a lesser extent in agriculture.  There are several advantages and disadvantages in the proposed practice.  However, existing technologies can help overcome such problems as for example the degradation and thus, the removal of pharmaceutical and xenobiotic compounds.     

In this study, Kandira stone, extensively used as a cladding material for building stone has been examined for the removal of an antibiotic Ciprofloxacin hydrochloride (CIP) from its aqueous solution. Batch experiments were performed to investigate the adsorption kinetics, equilibrium and thermodynamics between the adsorbent surfaces and CIP. The sorption data follows Freundlich isotherm. A chemical adsorption was dominant. The adsorption behaviour of CIP onto Kandira stone followed the pseudo-second-order kinetic model, indicating that the adsorption process can be expressed with the chemisorption mechanism. The intraparticle diffusion process is a rate-controlling step. The adsorption thermodynamic parameters of the free energy change (∆G^o), the isosteric enthalpy change (∆H^o) and the entropy change (∆S^o) were calculated. The negative ∆H^o values indicated that sorption of CIP was the exothermic process. The positive value of ∆G^o indicates non-spontaneous nature of CIP adsorption. 

An engine industry from Caxias do Sul city (RS, Brazil) has developed tests with biofuels to adapt their products to new fuel trends. Thus, this study aims to examine the components of their engines with potential degradation in the biodiesel usage. The most important aspects that were studied include fuel hoses, sealing rings and painting degradation. This work evaluated polymeric materials in terms of the direct contact with biodiesel from soybean in different proposed compositions with diesel fuel and compared the currently used materials with other elastomers that were proposed by the manufacturers of these components to choose the best performance for this application. The paint performance was also verified to evaluate the resistance aspects to fuels and to compare them to the proposed improvements to these engines. The results indicate that it is possible to use the proposed fuel hoses and sealing rings for some applications in specific biodiesel ratios. Additionally, the blistering and adhesion tests appear to be satisfactory for some of the studied systems.