<p>Eceng gondok (Eichornia crassipes) merupakan tanaman yang menjadi limbah perairan dan keberadaannya belum banyak dimanfaatkan. Kandungan selulosa, hemiselulosa, dan lignin di dalamnya dapat dimanfaatkan menjadi biogas melalui proses fermentasi. Penelitian ini mengkaji pengaruh EM4 (Effective Microorganism- 4) terhadap massa, nilai kalor, dan kecepatan pembentukan biogas dari eceng gondok. Percobaan dilakukan dalam anaerobic digester berukuran 4 liter, bahan baku yang digunakan adalah eceng gondok, rumen sapi, dan air dengan variabel penambahan EM4 sebesar 1% dan 0%. Fermentasi dilakukan secara batch dengan pengukuran gas (temperatur, tekanan, dan massa) setiap 7 hari sekali sampai hari ke-35. Sebelum proses fermentasi, dilakukan pengujian terhadap rasio C/N campuran bahan baku. Pembakaran gas dilakukan untuk membuktikan gas yang didapat mengandung metana. Hasil Penelitian menunjukkan bahwa rasio C/N untuk variabel dengan penambahan EM4 1% sebesar 5,33 dan rasio C/N untuk variabel dengan penambahan EM4 0% sebesar 7. Jadi, penambahan EM4 dapat menurunkan rasio C/N. Sementara itu, hasil fermentasinya memperlihatkan bahwa EM4 memperkecil produksi biogas meskipun proses pembentukannya cepat. Massa total biogas yang didapat pada variabel EM4 1% sebesar 1,1 g dan variabel EM4 0% sebesar 1,55 g. Tekanan<br />biogas mengalami fluktuasi (pada variabel EM4 1% sebesar 35,6 cmH2O, sedangkan pada variabel EM4 0% sebesar 40,6 cmH2O). Berdasarkan simulasi menggunakan chemical process simulator software, diketahui heating value biogas sebesar 39.180 kJ/kg.</p><p> </p><p>Water hyacinth (Eichornia crassipes) is a plant that becomes waste and its existence has not been widely used. Content of cellulose, hemicellulose, and lignin in it can be converted into biogas through a process of fermentation. Study examines the effect of EM4 (Effective Microorganism-4) on the mass, heating value, and the rate of formation of biogas from water hyacinth. An experiments were performed in anaerobic digesters size of 4 liters, the raw material used is water hyacinth, cow's rumen, and water with variable of EM4 addition of 1% and 0%. Fermentation was carried out in batch condition with gas measurement (temperature, pressure, and mass) every 7 days until the 35th day. Before fermentation, the C/N ratio of raw material mixture was analyzed. The gas was burnt to prove that the obtained gas containing methane. Results showed that the C/N ratio for the variable with the addition EM4 1% is 5.33 and C/N ratio for the variable with the addition EM4 0% is 7. Thus, the addition of EM4 can reduce C/N ratio. Despite the formation process is rapid, the results showed that EM4 reduce the biogas production. Total mass of biogas obtained at variable<br />EM4 1% is 1.1 g and variable EM4 0% is 1,55 g. Biogas pressure is fluctuated (at variable EM4 1% is 35.6 cmH2O, EM4 0% is 40.6 cmH2O). Based on simulation using the chemical process simulator software, it is known that biogas heating value is 39,180 kJ/kg.</p>
A new combination of substrates: biogas production and diversity of the methanogenic microorganisms
