Dielectric properties of coal ash

• Autorzy: González Valdes Laura , Friis Aage Valentin , Nowak-Woźny Dorota
• Języki publikacji: EN

Abstrakty

EN

Mineral matter of coal causes serious operational problems related to ash de- position in coal fired power plants such slagging and fouling, and so it has become the main subject of study in terms of current utilization. Moreover, the standardized tests currently used as the preferred predictive tools for slagging properties of coal sources have been lately reproved in the literature and un- certainties arrive due to the poor repeatability and reproducibility. That is why, methods for determining the sintering temperatures are being extensively investigated across the industry. This study focuses on the electrical properties of coal ash and its relation to the ash sintering process, where physical and chemical processes take part inside the material. The following methodology is based upon the continuous registration of the changes of resistance measured as an AC and DC property. The proposed laboratory stand allows measuring ‘in situ’ a coal ash sample being heated to analyse its electrical properties. It was found that the values measured are temperature dependent and could reflect the chemico-physical changes in the material, which may directly suggest the transformation of the intrinsic properties, giving insight into the sintering process.

Słowa kluczowe

EN

coal; mineral matter transformation; ash sintering; dielectrical properties

• Wydawca: Oficyna Wydawnicza Politechniki Wrocławskiej
• Czasopismo: Zeszyty Energetyczne
• Rocznik: 2018
• Tom: T. 5
• Strony: 51--60
• Opis fizyczny: Bibliogr. 24 poz., rys., wykr.

Twórcy

autor

González Valdes Laura

• Politechnika Wrocławska, Wydział Mechaniczno-Energetyczny, Katedra Technologii Energetycznych, Turbin i Modelowania Procesów Cieplno-Przepływowych

autor

Friis Aage Valentin

• Politechnika Wrocławska, Wydział Mechaniczno-Energetyczny, Katedra Technologii Energetycznych, Turbin i Modelowania Procesów Cieplno-Przepływowych

autor

Nowak-Woźny Dorota

• Politechnika Wrocławska, Wydział Mechaniczno-Energetyczny, Katedra Technologii Energetycznych, Turbin i Modelowania Procesów Cieplno-Przepływowych

Bibliografia

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Uwagi

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).