ANALISIS KESELAMATAN SISTEM KENDALI TUNGKU MUFFLE FURNACE ME-11 PADA PROSES REDUKSI GAGALAN PELET UO2 - Triarjo Triarjo; Sugeng Rianto Rianto (PIN Pengelolaan Instalasi Nuklir, 2019)
ABSTRAK - Proses reduksi di tungku Muffle Furnace ME-11 adalah proses pengolahan gagalan pelet UO2 menjadi serbuk UO2 yang menggunakan gas hidrogen sebagai pereduksi pada suhu± 800oC. Sistem Kendali logik pada tungku ini sangat diperlukan dengan titik berat faktorkeselamatan (safety) selama proses reduksi berlangsung, mengingat potensi bahaya gas hidrogen bersifat dapat mudah meledak pada kondisi tertentu. Sistem Kendali logik yang adapada sistem tungku Muffle furnace ME-11 terdiri dari sistem vacum, sistem pengaliran gas N2dan H2, sistem pembakar gas H2, sistem UPS (Uniterruptible Power Supply) dan alarm. Analisis keselamatan sistem kendali tungku Muffle Furnace ME-11 dilakukan untuk mengurangi kegagalan proses reduksi yang dilakukan dengan simulasi beberapa kondisi kegagalan, antara lain Supplai listrik utama (PLN) padam, api pembakar gas H2 menggunakan LPG padam, dan tekanan gas dalam tungku dibuat lebih tinggi atau rendah. Hasil analisis yang telah dilakukan pada sistem kendali logik terhadap kegagalan proses reduksi adalah sebagai berikut : apabila Supplai listrik utama padam maka alarm lampu indikator Power akan hidup, selanjutnya valve input H2 menutup, valve H2 output tetap membuka dan api pembakar gas H2 tetap menyala dengan supplai listrik oleh UPS. Apabila api pembakar gas LPG padam maka alarm dan lampu indikator Pilot Flame akan hidup, sistem pemantik menyala dan operator segera mengatur aliran gas LPG. Apabila tekanan di dalam tungku terlalu tinggi atau rendah saat beroperasi maka alarm dan lampu indikator tekanan akan hidup, pressure switch akan memerintahkan valve gas H2 menutup, selanjutnya operator mengatur tekanan melalui flowmeter gas H2. Hasil analisis sistem keselamatan kendali logik ini menunjukkan sistem kendali logik dapat berfungsi dengan baik, sehingga dapat menjamin keselamatan operasi proses reduksi dan kegagalan proses dapat dieliminasi saat operasi berlangsung.Kata kunci – Proses reduksi, Muffle Furnace, kendali logik ABSTRACT- The reduction process in the ME-11 Muffle Furnace furnace is the process of processing a UO2 pellet failure into UO2 powder using hydrogen gas as a reducing agent at ±800oC. Logic control system in this furnace is very much needed with the safety factoremphasizing during the reduction process, considering the potential danger of hydrogen gas can be explosive under certain conditions. The logical control system in the ME-11 Muffle furnace system consists of a vacuum system, an N2 and H2 gas flow system, an H2 gas burner system, a UPS and alarm system. Safety analysis of the Muffle Furnace ME-11 furnace control system was carried out to reduce the failure of the reduction process which was carried out by simulating several failure conditions, including the main electricity supply (PLN) outages, H2 gas burners using extinguished LPG, and the gas pressure in the furnace was made higher or low. The results of the analysis that have been carried out on the logical control system for the failure of the reduction process are as follows: if the main power supply goes out then the alarm indicator lights Power will turn on, then the H2 input valve closes, the H2 output valve remains open and the H2 gas burner flame stays on with the supply electricity by UPS. If the LPG gas burner extinguishes, the Pilot Flame alarm and indicator lights will on, the lighter system is on and the operator immediately regulates the LPG gas flow. If the pressure inside the furnace is too high or low when operating then the alarm and the pressure indicator lights on, the pressure switch will order the H2 gas valve to close, then the operator regulates the pressure through the H2 gas flowmeter. The results of the logic control system safety analysis shows that the logical control system can function properly, so as to ensure the safety of the reduction process operations and process failures can be eliminated during operations.Keywords - Reduction process, Muffle Furnace, logical control