Article
Analisis Karakteristik Biogass Limbah Perkotaan Sebagai Sumber Energi Terbarukan
Enthalpy : Jurnal Ilmiah Mahasiswa Teknik Mesin, Vol. 10 No. 3 (2025), hlm. 190–199
Abstrak
Biogas is a promising renewable energy alternative as it can reduce greenhouse gas emissions while simultaneously utilizing abundant urban organic waste as an energy source. However, the quality of biogas is strongly influenced by the type of waste, fermentation conditions, and the presence of impurities such as CO₂ and H₂S. This study aims to analyze the characteristics of biogas derived from restaurant waste, fruit waste, and tofu waste, and to evaluate its energy quality based on gas composition and flame characteristics. The method employed anaerobic fermentation with EM-4 starter on each sample weighing 7 kg, with water addition adjusted to the initial pH. As a variation, restaurant waste was also co-digested with rice straw. The fermentation process lasted for four weeks, during which temperature, humidity, pH, gas pressure, and mass were monitored daily. Gas composition was analyzed using a gas detector (LEL, O₂, CO, H₂S), while flame tests were performed to assess methane content. The results showed that restaurant waste produced biogas with the highest pressure, mass, and stability. This biogas generated a blue flame, indicating a high methane content (100% LEL). Conversely, fruit and tofu wastes failed to produce a flame due to dominant H₂S levels and low methane content. The addition of rice straw to restaurant waste improved gas pressure stability after 21 days. Although the initial flame quality was weak due to undecomposed lignocellulose, the flame volume was larger compared to biogas without rice straw. Thus, restaurant waste was identified as the most promising feedstock for urban biogas production. This study has several limitations, including the small laboratory-scale digester, short fermentation duration, and limited gas composition analysis. Future research should employ larger-scale digesters, apply more precise analytical methods such as GC-MS, determine calorific value, and explore co-digestion strategies to enhance methane yield and biogas quality. Keywords: Biogas, urban waste, renewable energy, anaerobic fermentation, flame characteristicsmi menghambat degradasi bakteri metanogen, sehingga produksi CH4 menurun.Studi ini merekomendasikan penelitian lebih lanjut tentang pengaruh pH, rasio C/N, metode penanganan limbah (seperti pencacahan atau pemanasan), dan mikroba pengurai efektif dalam fermentasi biogas. Penanganan H2S juga penting untuk mengurangi risiko korosi dan keracunan fatal.