Pengaruh penggunaan bahan bakar campuran oli bekas terhadap kandungan emisi gas buang dan konsumsi bahan bakar pada trainer mesin diesel common rail

Sindhu Arya Nugraha, Ir. Radhian Krisnaputra, S.T., M.Eng., IPM

2025 | Tugas Akhir | D4 TEKNIK PENGELOLAAN DAN PERAWATAN ALAT BERAT

Peningkatan konsumsi bahan bakar fosil di sektor industri dan transportasi serta tingginya volume limbah oli bekas (650 juta liter/tahun) di Indonesia menuntut adanya alternatif energi yang berkelanjutan. Penelitian ini bertujuan menganalisis pengaruh penggunaan campuran solar (CN 53) dan oli bekas hasil pirolisis terhadap performa dan emisi mesin diesel common rail. Pengujian dilakukan menggunakan variasi bahan bakar OB0 (0%), OB20 (20%), dan OB40 (40%) pada putaran mesin 800, 1.500, dan 2.000 rpm. Parameter yang diamati meliputi nilai kalor, Fuel Consumption (FC), Specific Fuel Consumption (SFC), serta emisi CO dan NOx. Hasil penelitian menunjukkan penambahan oli bekas menurunkan nilai kalor hingga 2,1% pada OB40 (46,23 MJ/kg). Penurunan kualitas pembakaran ini berdampak pada peningkatan konsumsi bahan bakar pada 2.000 rpm, FC OB40 meningkat 52,9?n SFC meningkat signifikan dibandingkan OB0. Dari sisi emisi, campuran oli bekas meningkatkan emisi CO secara drastis pada kondisi idle (800 rpm), namun mampu menurunkan CO pada putaran 1.500 rpm. Sebaliknya, emisi NOx justru mengalami perbaikan signifikan pada putaran 2.000 rpm, emisi NOx OB40 tercatat 33,8 ppm, jauh lebih rendah dibandingkan OB0 sebesar 61,7 ppm. Disimpulkan bahwa meskipun campuran oli bekas menurunkan efisiensi bahan bakar, bahan bakar ini memiliki potensi dalam mereduksi emisi NOx pada putaran mesin tinggi.

The increasing consumption of fossil fuels in Indonesia’s industrial and transportation sectors, together with the large volume of waste lubricating oil generated annually (approximately 650 million liters), highlights the need for sustainable energy alternatives. This study investigates the effects of blending diesel fuel (cetane number 53) with pyrolyzed waste oil on the performance and exhaust emissions of a common rail diesel engine. Experimental tests were conducted using three fuel blends: OB0 (0%), OB20 (20%), and OB40 (40%), at engine speeds of 800, 1,500, and 2,000 rpm. The evaluated parameters included calorific value, fuel consumption (FC), specific fuel consumption (SFC), and CO and NOx emissions. The results show that the addition of waste oil reduced the calorific value by up to 2.1% for OB40, reaching 46.23 MJ/kg. This reduction in fuel quality adversely affected combustion efficiency, leading to higher fuel consumption at 2,000 rpm, where FC for OB40 increased by 52.9% and SFC rose considerably compared to OB0. In terms of emissions, waste oil blends caused a substantial increase in CO emissions under idle conditions (800 rpm), while a reduction in CO emissions was observed at 1,500 rpm. Conversely, NOx emissions exhibited a significant improvement at higher engine speeds. At 2,000 rpm, NOx emissions for OB40 were recorded at 33.8 ppm, substantially lower than those of OB0 at 61.7 ppm. Overall, although waste oil blends reduce fuel efficiency, they demonstrate strong potential for NOx emission reduction at high engine speeds.

Kata Kunci : Mesin Diesel, Common Rail, Emisi Gas Buang, Konsumsi Bahan Bakar, Nilai Kalor, Oli Bekas.