DESAIN KONSEP TANGKI PENAMPUNG BAHAN BAKAR PASSIVE COMPACT MOLTEN SALT REACTOR

Abstract

Passive Compact Molten Salt Reactor (PCMSR) merupakan pengembangan dari reaktor MSR. Desain reaktor PCMSR membutuhkan tempat khusus penampung sementara bahan bakar pada saat terjadi insiden, misalnya kecelakaan yang menyebabkan peningkatan suhu bahan bakar. Tangki penampung bahan bakar tersusun dari 3 bagian yang saling terhubung yaitu bagian penampung cairan bahan bakar, cerobong (chimney), dan penukar kalor. Dalam penelitian ini, tangki dimodelkan secara lump dan dilakukan variasi daya awal reaktor dan ketinggian cerobong. Syarat batas model ditetapkan suhu bahan bakar maksimum 1400 °C, yang didasarkan pada titik didih larutan garam LiF-BeF₂-ThF₄-UF₄. Analisis dilakukan dengan cara menghitung rugi tekanan total dan transfer kalor untuk variasi daya awal antara 1800-3000 MWth dan ketinggian cerobong antara 1-10 m. Hasil penelitian menunjukan semakin besar daya reaktor, maka tinggi tangki penampung bahan bakar dan tinggi alat penukar kalor yang dibutuhkan akan semakin besar, tejadi kenaikan suhu fluida pendingin dan suhu udara pendingin, dan menyebabkan kenaikan laju aliran masa fluida pendingin, sedangkan laju aliran masa udara menurun. Peningkatan ketinggian cerobong menyebabkan ketinggian tangki penampung bahan bakar dan ketinggian alat penukar kalor semakin menurun, penurunan suhu fluida pendingin, tetapi suhu udara meningkat, dan menyebabkan peningkatan laju aliran masa fluida pendingin, tetapi laju aliran masa udara akan semakin menurun.

Kata kunci: PCMSR, cerobong, alat penukar kalor, variasi daya.

The Passsive Compact Molten Salat Reactor (PCMSR) reactor is developed from MSR reactor. The PCMSR reactor design requires special place to temporarily storage for reactor fuel when incident occurs, such as when there is an accident which caused the temperature of the fuel increases. The tank consist of three interconnected parts, the reservoir liquid fuel, chimney, and the heat exchanger. In this research, the tank system is modeled based on a lump model and with variation of the initial power and height of chimney. Model boundary conditions set at the maximum fuel temperature of 1400°C, which is based on the molten salt LiF-BeF₂-ThF₄-UF₄. In this analysis, calculation of pressure drop and heat transfer are conducted for 1800-3000 MWth and for chimney height variations were analyzed at height of 1-10 m. Results show that the larger power in reactors, the fuel tank height and the height of heat exchanger equipment required will be greater, increasing cooling fluid temperature and air temperature, increasing cooling fluid mass flow rate while the air mass flow rate decreases. Increasing the height of chimney causes height of the fuel tank and the height of the required heat exchanger decreases, decreasing coolant fluid temperature, but the air temperature will increase, causing cooling fluid mass flow rate will increase but the air mass flow rate will decrease.

Keywords: PCMSR, chimney, heat exchanger, power variation