Ahmed El-Kammar

Hydrogeochemical evolution of inland lakes’ water: A study of major element geochemistry in the Wadi El Raiyan depression, Egypt

Wadi El Raiyan is a great depression located southwest of Cairo in the Western Desert of Egypt. Lake Qarun, located north of the study area, is a closed basin with a high evaporation rate. The source of water in the lake is agricultural and municipal drainage from the El Faiyum province. In 1973, Wadi El Raiyan was connected with the agricultural wastewater drainage system of the Faiyum province and received water that exceeded the capacity of Lake Qarun. Two hydrogeological regimes have been established in the area: (i) higher cultivated land and (ii) lower Wadi El Raiyan depression lakes. The agricultural drainage water of the cultivated land has been collected in one main drain (El Wadi Drain) and directed toward the Wadi El Raiyan depression, forming two lakes at different elevations (upper and lower). In the summer of 2012, the major chemical components were studied using data from 36 stations distributed over both hydrogeological regimes in addition to one water sample collected from Bahr Youssef, the main source of freshwater for the Faiyum province. Chemical analyses were made collaboratively. The major ion geochemical evolution of the drainage water recharging the El Raiyan depression was examined. Geochemically, the Bahr Youssef sample is considered the starting point in the geochemical evolution of the studied surface water. In the cultivated area, major-ion chemistry is generally influenced by chemical weathering of rocks and minerals that are associated with anthropogenic inputs, as well as diffuse urban and/or agricultural drainage. In the depression lakes, the water chemistry generally exhibits an evaporation-dependent evolutionary trend that is further modified by cation exchange and precipitation of carbonate minerals.

Upgrading of Oil Shale by Flotation Without Collector

Oil shale impurities prevent its direct usage as a source of energy. Removing or reducing of these impurities before retorting can reduce the cost of oil shale processing. In that regard, pretreatment of oil shale by flotation represents one of the favorable solutions. Therefore, in this work, (a) microscopic examinations were carried out to study the mineralogical characteristics of oil shale sample and (b) flotation of oil shale was used to separate organic matter (kerogen) from associating gangue by adjusting the flotation pH, stirring speed and pulp density without adding a collector. The results of oil shale characterization showed that kerogen content in the studied sample was 10%, while the results of flotation experiments proved the possibility of oil shale upgrading to about 20% kerogen with recovery reaching to more than 70%.

Mineralogical and geochemical characterization of natural zeolites from southwest Syria

The zeolitic minerals were recorded in association with the Upper Pliocene volcanic sequences in the southwestern region of Syria. As far as the authors are aware, the present work is first to characterize these potential deposits from the mineralogical and geochemical points of view. Three natural zeolite samples were collected from sedimentary–pyroclastic deposits of Om Ozon (OZ), Mukeihlat (MK), and Jabal Al-Sis (JS) areas. These samples were studied by x-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, x-ray fluorescence spectrometer (XRF), scanning electron microscopy (SEM), in combination with thermo analytical methods (differential thermal analysis (DTA) and thermo gravimetric analysis (TGA)). A variety of zeolite species, including phillipsite, analcime, and chabazite were identified in addition to variable quotients of calcite and quartz. Several characteristics of these minerals were determined such as chemical functional groups, chemical components, morphology of crystals, and thermal behaviors.

Effect of mineralogical composition and kerogen content on oil shale natural floatability

ABSTRACT Mineralogical composition is one of the important factors that affect the performance of separation processes. In the current study, two oil shale samples, from El-Nakhil and El-Bieda localities, differ in their mineralogical composition, were subjected to flotation tests. Chemical analysis, differential thermal analysis (DTA), thermo-gravimetric analysis (TGA), and microscopic examination are among the used characterization techniques. In addition, their responses for upgrading by flotation were conducted as a function of pH, solid-liquid ratio, stirring speed and different particle sizes. The characterization results indicated that the kerogen content in El-Nakhil sample was 30% while in El-Beida sample was 10%. On the other hand, the flotation results indicated that El-Bieda responses better than that of El-Nakhil in terms of the difference in kerogen % between the original sample and the concentrated ones. The difference in flotation results of two samples can be explained by the difference in kerogen morphology as well as its interaction with surrounding matrix. In El-Bieda the kerogen has a laminated structure but in El-Nakhil it appears as laminated liptinitic component, in addition to the higher carbonate content in El-Nakhil sample in comparison to higher clay content in El-Bieda sample.