Sr isotopes in the Tortonian-Messinian Lake Bira and Gesher marshes, Northern Valleys of Israel: Implications for hydroclimate changes in East Mediterranean−Levant margins

87Sr/86Sr isotope and Sr/Ca ratios in lacustrine carbonates were used to reconstruct the hydroclimate conditions in the watershed of Lake Bira that filled during the Tortonian-Messinian the tectonic depressions of the Northern Valleys of Israel in the East Mediterranean-Levant region. 87Sr/86Sr ratios of the Tortonian (ca. 10−8 Ma) carbonates of ∼0.7075 and the great expansion of the lake indicate wet conditions and enhanced supply of freshwater from the regional Mesozoic aquifers. Upon the transition to the Messinian period (ca. 7−6 Ma), the 87Sr/86Sr ratios in the carbonates rose to ∼0.7080−0.7085, reflecting the contribution of Sr from Sahara Desert dusts that came to comprise the regional surface cover. This contribution is also reflected in the silicate fraction of the lacustrine formations that show “granitic-crustal” 87Sr/86Sr ratios of ∼0.711. During the Messinian salinity crisis (5.9−5.6 Ma), the region became arid and Lake Bira possibly dried. Later, during the Lago Mare stage (ca. 5.5−5.3 Ma), the rainfall increased and paludal waterbodies scattered the area of the larger Lake Bira.

Displacement of the Ingnition Furnace in the Iron Ore Sintering with Re-Circulation of Waste Gases

In search of new technologies for the iron ore sintering process, the re-circulation of waste gases in the process can provide some advantages in relation to the conventional process. For such study, a sintering multi-phase model was used for the assessment of the re-circulation of waste gases in the process. Five cases of re-circulation of waste gases in the sintering process were analyzed, always aiming at a stable operation in the process. The results of the simulation indicate an enlargement of the combustion front with the re-circulation of the waste gases and the possibility of existing a reduction of the solid fuel consumption. As a result, there was an increase of the calcium-silicate fraction, providing a sinter reducibility improvement, apart from the reduction of the emission of CO2 and PCDD/Fs in the sinter machine.

High Temperature Removal of Alkali and Particulates in Pressurized Gasification Systems

Extensive thermodynamic and preliminary experimental studies have identified the potential use of aluminosilicate materials to simultaneously remove volatile alkali and particulate released during pressurized gasification of coal. The gettering capacity of three selected materials have been evaluated in a bench-scale reactor operating at 1114 kPa total pressure and 1123–1173K in alkali-laden inert, and simulated fuel gas environments. At 1123 K, alkali gettering has been established to result through reaction within the amorphous acid-insoluble alumino-silicate fraction of these materials, while at 1173 K saturation of the insoluble matrix is achieved, with gettering occurring mainly through acid-soluble complexes. The gettering mechanism as either a chemical reaction or a physical adsorption phenomenon and reaction kinetics will be delineated through future thermogravimetric (TG) analyses.

5. The Chemical Relationship between Howardites and the Silicate Fraction of Mesosiderites

Analyses of eleven major elements in five howardite samples and in the silicate fraction of seven mesosiderites are presented in a recalculated form and compared. The mesosiderite silicate fractions show distinct differences in chemical composition from the howardites, but the average Ca/Al determined for mesosiderites (1.05), which differs from most values previously published, is close to that typical of howardites (1.08). The inverse Ca/Mg relationship in the howardites is present also in the mesosiderites, the trend being displaced relative to that of the howardites but parallel to it. The chemical differences confirm that mesosiderites are not mixtures of howardite and metal. The Ca/Al and Ca/Mg relationships suggest that the two meteorite groups were subject to similar genetic controls, and may therefore have had a common parent body. Such a body is required by the cooling rate of the metal of mesosiderites to have been larger than any known asteroid.