Yazar "Elmas, Numan" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Öğe
    Environmental and depositional characteristics of diatomite deposit, Alayunt Neogene Basin (Kutahya), West Anatolia, Turkey
    (Springer, 2013) Elmas, Numan; Bentli, Ismail
    This paper describes the geological-depositional and environmental characteristics of diatomite. The diatomite deposit is situated in the southern part of the Alayunt (Kutahya) Basin. Samples of 18 diatomites and 12 host rocks were collected from four sedimentary profiles in the spring season. Basement rocks are Paleozoic-aged metamorphic rocks (schist, phyllite, quartzite, etc.) and Mesozoic-aged ophiolitic and complex rocks. Host rocks are rhyodacitic-rhyolitic tuffite, volcanic glass. Diatomite is composed of Upper Miocene-Upper Pliocene-aged diatom species. Diatomite shows layer morphology and lies on volcanic glass layer. XRD characteristic peaks of diatomite show that it comprises dominantly of Opal-A silica, whereas volcanic glass has Opal-CT constituent. SEM and NPM photomicrographs indicate that diatomites are dominantly composed of benthic freshwater diatom species, such as Pinnularia microstauron, Pinnularia lundii, Pinnularia subrostrata, Pinnularia brevicostata, Pinnularia tenuis, Pinnularia sp., Navicula eligensis, Fragilaria construens, Mastogloia braunii Grunow, Melosira varians Agardh, Surirella capronii Br,bisson, Cymbella lanceoloata, Amphora venata, Gomphonema germainii, Gomphonema angustatum and Rhapalodia gibba. These species are general indicators of shallow paleolake environment and cool climate conditions. Due to the fluvial currents and climatic conditions; lake water levels, temperature and nutrient content fluctuated through the time. Chemical data obtained from 18 diatomite samples show that while silica is the bodybuilding material for diatomite (over 89 % SiO2), Al, Mg and Fe contents of diatomite samples might be derived from clastic materials. The concentration of Al, Mg and Fe decreases toward the lake center. Diatom genera, sedimentary profile sections and mineralogic data suggest that diatomite deposited in lacustrine-type freshwater shallow lake is associated with Upper Miocene-aged extension tectonics. Physical and filtration tests along with environmental characteristics of diatomite suggest that calcined diatomite can be used for waste treatment processes in the filter aid industry.
  • Küçük Resim Yok
    Öğe
    Magnesite concentration technology and caustic - calcined product from Turkish magnesite middlings by calcination and magnetic separation
    (Taylor & Francis Inc, 2017) Bentli, Ismail; Erdogan, Necmettin; Elmas, Numan; Kaya, Muammer
    This paper deals with the current magnesite concentration technology and upgrading studies in Turkey, which is the second biggest magnesite and third biggest sinter magnesia producer in the world. Magnesite heat treatment and magnetic separation fundamentals are also covered. This study aims to concentrate magnesite middlings containing the silica/iron impurities from Kutahya, Turkey, by calcination and dry magnetic separation. Final calcined MgCO3 product contains 89.57% MgO, 0.96% SiO2, 0.43% Fe2O3, 2.35% CaO and 6.64% loss of ignition. The optimum particle size was determined at -8 + 0.5 mm at 1000 degrees C. Final product is saleable for industrial applications (i.e., soil decontamination, panels, fertilizers, animal nutrition, abrasives).