Miyosen yaşlı Muğla-Hüsamlar linyitlerinin özellikleri

Bu çalışmada Muğla Kömür Sahası (GB Türkiye) bulunan Hüsamlar Kömür Sahası?ndan üretilen kömürlerin bileşenleri ve petrografik özelliklerinin belirlenmesi ve bu özelliklerin kömürün yoğunluğa bağlı olarak zenginleştirilmesi üzerindeki etkilerinin araştırılması amaçlanmıştır. Hüsamlar Kömür Sahası içinde işletilen kömür damarı matriks kömür ve inorganik ara kesmelerden oluşan bantlı bir yapı gösterir. Çalışmada kullanılan kömür ve inorganik tortul örnekleri Hüsamlar açık işletmesinde kanal örneklemesi yöntemi uygulanarak toplanmıştır. Örnekler makroskopik olarak linyit, az-orta jelleşmiş matriks litotipine sahiptir. İnorganik bileşenleri kiltaşı, çamurtaşı, silttaşı ve kireçtaşı oluşturur. Ortalama toplam nem yüzde 20,50; kül miktarı yüzde 20,73 (kuru bazda); uçucu madde içeriği yüzde 60,71; karbon içeriği yüzde 39,29 (kuru, külsüz bazda) ölçülmüştür. Linyitin elementer içeriği (bütün değerler ağırlıkça yüzde, kuru, külsüz bazda) karbon yüzde 61,1; hidrojen yüzde 7,7; nitrojen yüzde 1,9; kükürt yüzde 7,1 ve oksijen yüzde 22,2 şeklindedir. Üst kalorifik değer göz önüne alındığında Hüsamlar kömürü B-A düşük dereceli kömür aralığına aittir. On yedi linyit örneği kömür petrografisi mikroskobunda, beyaz ve mavi ışık uygulanarak incelenmiştir. Hüminit grubu maseralleri yaygın, inertinit seyrek olarak bulunurken liptinit içeriği oldukça değişkenlik göstermektedir. Maseral içeriği baz alındığında Hüsamlar turbası limnotelmatik ortamda, fende, anoksik, mezotrofik koşullarda birikmiştir. Rastgele hüminit yansıtması ortamala 0,25 olup turba ve linyit arası kömürleşme derecesine denk gelir. Hüsamlar kömür örnekleri kalsit, aragonit, kuvars, pirit, feldspat ve kil mineralleri içermektedir. Yoğunluk ayırma tekniği onbir örnekte denenmiş, başarısızlıkla sonuçlanmıştır. Deneyler için geçirilen sürenin yetersizliği nedeniyle deneylerin tekrarı tamamlanamamış ve ileriki çalışmalara bırakılmıştır. The Hüsamlar coal deposit is located in the Muğla Basin, SW Turkey. It is exploited for power generation. The seam displays a banded structure consisting of matrix coal and inorganic intercalations. Coal and inorganic sediment samples were collected from one site in the Hüsamlar Open Pit applying channel sampling. Macroscopically, the lignite belongs to the light- to medium- gelified matrix lithotype. Inorganics mostly include claystone, mudstone, siltstone and limestone. On average, total moisture is 20.50 wt. percent and ash yield 20.73 wt. percent (on dry basis), volatile matter and fixed carbon contents 60.71 wt. percent and 39.29 wt. percent (on dry, ash-free basis), respectively. The elemental composition of lignite proved to be as follows (all values in wt. percent, on dry, ash-free basis): carbon 61.1, hydrogen 7.7, nitrogen 1.9, sulphur 7.1 and oxygen 22.2. The gross calorific value is around 19.6 MJ/kg (on moist, ash-free basis). Considering the gross calorific values the Hüsamlar coal belongs to the low rank coal B to A. Seventeen lignite samples were examined under the coal-petrography microscope under white incident light and blue-light excitation. Macerals of huminite group are the most abundant, inertinite is rare, whereas liptinite content strongly varies. On the basis of maceral composition the Hüsamlar peat was accumulating in a limnotelmatic environment, in a fen (topogenous mire), under anoxic, mesotrophic conditions. The maceral content indicates that the peat-forming vegetation consisted of both arboreal plants and herbs. The random reflectance of huminite is about 0.25 percent pointing to, coal rank between peat and lignite. The lignite proved to contain calcite, aragonite, quartz, pyrite, feldspar and clay minerals. Density separation technique was applied on eleven lignite samples. But the procedure failed and the lack of time did not allow further experiments

Palaeoenvironmental reconstruction of hüsamlar coal seam, SW Turkey

© Indian Academy of Sciences.The Ören and Yatağan Basins in SW Turkey host several Miocene coal deposits currently under exploitation for power generation. The present study aims to provide insight into the palaeoenvironmental conditions, which controlled the formation of the Hüsamlar coal seam located in Ören Basin. The coal seam displays many sharp alternations of matrix lignite beds and inorganic, lacustrine sediment layers. The coal is a medium-to-high ash lignite (10.47–31.16 wt%, on dry basis) with high total sulphur content (up to 10 wt%, on dry, ash-free basis), which makes it prone to self-combustion. The maceral composition indicates that the peat-forming vegetation consisted of both arboreal and herbaceous plants, with the latter being predominant in the upper part of the seam. Mica and feldspars contribute to the low part of the seam; carbonates are dominant in the upper part, whereas quartz and pyrite are present along the entire coal profile. The sudden transitions of the telmatic to the lacustrine regime and reverse is attributed to tectonic movements that controlled water table levels in the palaeomire, which affected surface runoff and hence, clastic deposition

Palaeoenvironmental reconstruction of Hüsamlar coal seam, SW Turkey

© Indian Academy of Sciences.The Ören and Yatağan Basins in SW Turkey host several Miocene coal deposits currently under exploitation for power generation. The present study aims to provide insight into the palaeoenvironmental conditions, which controlled the formation of the Hüsamlar coal seam located in Ören Basin. The coal seam displays many sharp alternations of matrix lignite beds and inorganic, lacustrine sediment layers. The coal is a medium-to-high ash lignite (10.47–31.16 wt%, on dry basis) with high total sulphur content (up to 10 wt%, on dry, ash-free basis), which makes it prone to self-combustion. The maceral composition indicates that the peat-forming vegetation consisted of both arboreal and herbaceous plants, with the latter being predominant in the upper part of the seam. Mica and feldspars contribute to the low part of the seam; carbonates are dominant in the upper part, whereas quartz and pyrite are present along the entire coal profile. The sudden transitions of the telmatic to the lacustrine regime and reverse is attributed to tectonic movements that controlled water table levels in the palaeomire, which affected surface runoff and hence, clastic deposition

Development of a petrographic classification system for organic particles affected by self-heating in coal waste. (An ICCP Classification System, Self-heating Working Group - Commission III)

Self-heating of coal waste is a major problem in the leading coal-producing and consuming countries, independent of the recent or past coal exploitation history. The phenomenon of self-heating is dependent on many factors such as the properties of organic matter (maceral composition and rank), moisture and pyrite content, climate effects, and storage conditions (shape of the dump or compaction of the coal waste). Once deposited, coal waste undergoes oxidation, which can lead to self-heating with the overall temperatures exceeding 1000 degrees C. During these self-heating processes, both organic and mineral matter undergo oxidative and thermal alterations, being influenced, among others, by the rate of heating as well as by the access of air and moisture. The morphological features of organic matter in coal waste at microscopic scale reflect the thermal conditions within the waste dump. Since 2008, several exercises designed to establish a petrographic classification system of oxidatively- and thermally-altered morphological forms of organic particles present in self-heated coal waste dumps have been carried out within the Self-heating of Coal and Coal Waste Working Group (Self-Heating WG), in Commission III of the International Committee for Coal and Organic Petrology (ICCP). Based on the degree of oxidative and thermal alteration, all assessed organic particles were divided into unaltered particles (huminite, vitrinite, liptinite, and inertinite macerals), altered particles, and newly formed particles (pyrolytic carbon, bitumen, chars, graphite, and coke). Altered particles were further divided according to their optical properties (porous, massive; isotropic, anisotropic). For altered particles the following specific features were distinguished: fractures, fissures, cracks; brighter rims; darker rims; plasticised edges; bands; devolatilisation pores; paler in colour particles. The final petrographic classification of oxidatively- and thermally-altered morphological forms of organic particles in coal waste dumps was established as a result of the successively performed Round Robin Exercises 2008-2017. The selected criteria and categories proved the high performance of the analysts characterised by a minor bias. The proposed petrographic classification system based on petrographic methods represents a useful way to characterize the undesirable phenomena occurring in coal waste dumps. Microscopic analyses and application of the petrographic classification system for organic particles affected by self-heating in coal waste offers the identification, documentation and monitoring of coal waste oxidation, self-ignition and combustion processes. It also enables a selection and application of appropriate measures to delay or even prevent undesired environmental impacts. The established classification system may assist in the air quality monitoring and assessment of burning waste dump sites and, thus, provide a relevant support in the environmental management of the disposal sites related to coal mining. The classification system can provide an important instrument for environmental protection agencies to increase the effectiveness of measures applied in fire hazard combating. The proposed classification of oxidatively- and thermally-altered morphological forms of organic particles in coal waste dumps can be applied on self-heating coal waste or mining dumps research, being a useful tool for coal waste managements performed by environmental agencies responsible for the landfill managements and monitoring of waste dumps