Enhancement of Technical and Economic Indicators of Power-Generating Units of Thermal Power Plants by Eliminating Flue Gas Recirculation

Boiler units at Ukrainian thermal power plants need to be modernized or replaced in the short run, as this is important for the national energy security. The authors determined one of possible ways to improve the efficiency indicators of coal-fired boiler units and power generating units as a whole up to the values exceeding the design ones. This variant of improvement consists in abandoning the technology of using flue gas as drying agent in pulverized coal systems and replacing it with direct discharge of the gas flow into the boiler furnace. Numerous computations were carried out to study the change of efficiency indicators and manoeuvrability of power generating units due to the replacement of the ball mill pulverizing system using flue gases for coal drying with the scheme including ball-and-race mills that use hot air as drying agent.

Pemanfaatan Batubara Kalori Rendah Pada PLTU untuk Menurunkan Biaya Bahan Bakar Produksi

Tingginya jumlah sumber daya dan cadangan batubara kalori rendah, perlu untuk ditingkatkan pemanfaatannya. Penyediaan energi sampai dengan tahun 2050 diperkirakan tetap didominasi oleh energi fosil. Energi fosil yang tumbuh paling pesat adalah batubara karena sektor pembangkit listrik didominasi oleh PLTU batubara. Sebagai salah satu upaya untuk memanfaatkan batubara nilai kalori rendah yang mempunyai harga energi yang relatif lebih murah, maka dapat dilakukan alternatif pemanfaatan batubara tersebut dengan metode coal blending, coal switching, ataupun coal drying pada PLTU. Coal blending merupakan cara terbaik untuk mengatasi masalah ketersediaan batubara dan ketergantungan terhadap satu sumber pemasok batubara untuk PLTU di Indonesia. Dengan mengganti batubara menjadi kalori yang lebih rendah (coal switching) memang akan menaikkan jumlah konsumsi batu bara, namun karena harganya lebih murah, maka masih didapat penghematan secara finansial. Coal drying dapat menjadi salah satu alternatif untuk memperbaiki kualitas batubara yang mempunyai kandungan moisture tinggi, sehingga batubara tersebut dapat digunakan untuk bahan bakar PLTU eksisting.

Low rank coal drying technology for decreasing electricity cost production: case study of Nagan Raya power plant

Considering the depletion of black coal resources, utilization of low rank coal currently is emerging to meet the growing of electricity consumption globally. Some coal fired power plants urge to use the domestic low rank coal due to some financial reasons. They are several coal drying technologies have been proposed. This study analyzes the utilization low rank coal to decrease the electricity cost production at Nagan Raya coal fired power plant. The Coal Moisture Control Fluidized Bed (CMC-FB) technology is selected as a basis for both technical and financial calculation. Based on the pilot project in Fukuoka, this technology is technically feasible and well suited for Nagan Raya power plant. A financial modelling shows that coal drying technology implementation can potentially decrease the electricity cost production for the utility and also make benefits for the investor. Further research is recommended to investigate other proven technologies. Additionally the effect of coal drying implementation to the environment should be noticed.