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In broad sense definition, the limestone is any rock rich in CaCO3. Limestone can be obtained from a variety of sources and various limestones differ considerably in their chemical compositions and physical structure. The chemical and physical properties of carbonate rocks are interdependent. Physical characteristics of limestone play an important role in evaluating a deposit. Certain physical characteristics in limestones may indicate a general disposition description during calcination. However, all stones with these characteristics will not decrepitate. Limestones display the following attributes or conditions, alone or in combination, are prone to decrepitation; coarse crystallinity, friability, foliation, excessive calcite veining, microfracturing, highly porous and thinly bedded. The chemical reactivity of different limestones shows a large variation due to their differences in crystalline structure and the nature of impurities such as silica, iron, magnesium, manganese, sodium and potassium. Magnesium and ferrous iron cations occurring in limestone may change the carbonate mineralogy of limestone as well as its physical characteristics such as colour, brightness, specific gravity, hardness, tenacity and decomposition properties 1,2 .The main chemical property of limestone is its thermal decomposition, known as calcination, during which lime (CaO) and carbon dioxide are produced (eqn. 1) 1,3 . The calcination process is explained with a partly decomposed piece of carbonate

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This article deals with overview of Turkey's coal necessity, reserves and utilization. Turkey is rapidly growing in terms of both its economy and its population. In parallel, its demand for energy, particularly for electricity, is increasing. Turkey possesses fossil fuel resources of hard coal (HC) and lignite (LG) have the greatest importance in energy production and for the national economy. The hard coal and lignite reserves of Turkey are 1.126 and 8.375 millions tons(Mt), respectively. Coal, the major fuel source for turkey utilized mainly for electric power, steel manufacturing and cement production, amounts to 31% of total energy consumption in Turkey. To sum up, providing the total consumption is taken into account in the Middle East, the coal consumption rate of Turkey is approximately 90% of the consumption in this region.

Ultrasonik teknikler madencilik alanında ve jeoteknik uygulamalarda yaygın olarak kullanılmaktadır. Kayaç numuneleri üzerine kolay uygulanabilmesi, ekonomikliği ve basit bir şekilde numune hazırlanması vb. gibi olumlu özellikleri yöntemi çekici hale getirmektedir. Doğal taşların ultrasonik iletkenliğini etkileyen pek çok faktör mevcuttur. Bu çalışma kapsamında; farklı bölgelere ait kireçtaşı mermerlerinin tek eksenli basınç dayanımı, su emme oranı, Shore sertliği ve özgül ağırlıkları laboratuvar ortamında belirlenmiş ve P dalga hızı ile basit ve çoklu regresyon analizleri yapılarak ampirik formüller elde edilmiştir. Regresyon analizi, P dalga hızı değerlerinin tek eksenli basınç dayanımı, su emme oranı, Shore sertliği ve özgül ağırlık değerleri ile kuvvetli bir ilişki olduğunu göstermektedir.

ÖzetYapılan çalışmada, kalsiyum hidroksit çözeltisinden çöktürülmüş kalsiyum karbonat (ÇKK) üretimi incelenmiştir. Uygulanan sistem oldukça basit ve çevre dostu bir karbonizasyon prosesidir. Çalışmada Kalsiyum hidroksit çözeltisine karbondioksit püskürtülerek katkı maddesi kullanılmaksızın kalsiyum karbonat (CaCO 3 ) üretimi gerçekleştirilmiştir. Çöktürülmüş kalsiyum karbonat, birbirine yakın tane aralıklarında ve skalenohedral (triangular) kristal şekilli kalsit olarak üretilmiştir. Üretilen sentetik kalsitlerin bileşimi, kristal yapısı/mineralojisi, tane boyutu ve özgül yüzey alanı XRF, XRD, SEM ve mastersizer kullanılarak belirlenmiştir.Anahtar Kelimeler: Sentetik, Kireçtaşı, Kireç, ÇKK, Karbondioksit Production of Precipitated Calcium Carbonate AbstractIn this study, the production of precipitated calcium carbonate (PCC) from a suspension of calcium hydroxide was investigated. The applied system is a simple and eco-friendly carbonation process. Carbon dioxide is blown into a suspension of calcium hydroxide, and the resulting calcium carbonate (CaCO 3 ) is recovered without any additives. Precipitated calcium carbonate is produced as an uniform particle size and a scalenohedral crystalline shaped calcite. The synthesized calcite was analyzed by XRF, XRD, SEM and mastersizer to identify the content, phase, particle size and specific surface area.