No abstract

Biogas decomposes organic waste by bacteria through an anaerobic fermentation process that produces manageable methane gas. The purpose of this study was to determine the temperature, pressure, mass and flame duration of biogas produced from a mixture of cow dung and tofu waste liquid waste using a batch type digester. The digester uses a volume capacity of 30 liters with a volume of stuffing raw material as much as of the volume of the digester. This study uses three variations of the volume ratio of the mixture of cow dung and tofu waste liquid waste, namely S1 (50%: 50%), S2 (70%: 30%), and S3 (90%: 10%) with the addition of 2.5 liters of water for each variation. Data collection was carried out for 30 days at 11.00 WITA and 17.00 WITA. Based on the results of the study, it is known that the mixed variation of 50%: 50% is the best variation compared to the variations of 70%: 30%, and 90%: 10%. The results of the daily average environmental temperature variation of the S1 mixture are 30.19°C, and the average substrate temperature are 27.06°C. The average daily yield of biogas pressure are 0.039 bar with a total mass of biogas are 57.8 grams. Based on the measurement results of biogas flame duration comparasion with LPG on the total mass of biogas with the variation of the S1 mixture, it is obtained that biogas flame duration are 4.38 minutes while the combustion of LPG gas with the same total mass are 49 seconds.

Biogas is a combustible gas produced by anaerobic activity or the fermentation of organic matter by microorganisms. This study produces biogas made from chicken manure and cow manure with a ratio of mass composition D1 (25%: 75%), mass composition D2 (50%: 50%), and mass composition D3 (75%: 25%) with a combined mixture that is 75% of the digester capacity and the addition of beef rumen by 1 kg in all variations as a starter. The purpose of this study was to examine the effect of composition on pressure, mass, temperature, and flame quality of the biogas production of chicken manure and cow manure with a mixture of cow rumen. Data were collected every 06.00 WITA and 18.00 WITA and temperature measurements were every 6 hours for 20 consecutive days. The results showed that the temperature at 18.00 WITA was better than at 06.00 WITA with the highest temperature occurring in the D2 variation of 29.85oC. The results of the measurement of biogas mass and pressure showed that the highest value was in the D3 variation at 18.00 WITA on the day to -9 with values ​​of 68.32 grams and 0.054 bar, respectively, with the total mass and pressure of biogas in the D3 variation of 401.14 grams and 0.391 bar.   Keywords: Biogas, Chicken Manure, Cow Manure, and Cow Rumen.

Kota Balikpapan menghasilkan sampah 350 ton di tahun 2020 dengan peningkatan 10% di setiap tahunnya, keberadaan sampah organik berlimpah dan kuantinyu merupakan potensi sumber energi biogas. Maka dilakukan penelitian terhadap campuran substrat biogas yaitu limbah peternakan dan limbah pasar. Tiga variasi substrat kotoran sapi terhadap limbah pasar pada digester dA, dB dan dC yaitu dA 40% :30%, dB 30% : 40% dan dC 35%: 35% dengan kandungan air dadalah 30%. Parameter penelitian temperatur lingkungan sekitar digester, tekanan didalam digester, massa gas hasil digester dan nyala api. Diketahui bahwa penambahan substrat kotoran sapi menghasilkan tekanan lebih tinggi dengan waktu singkat yaitu pada pengukuran pukul 10:00 pagi yaitu tekanan digester dA 0.062 bar dihari ke-3 dan massa  0.6 gr di hari pertama. Pada digester dB nilai tertinggi 0.052 bar dan 0.5 gr di hari ke-4, serta 0.061 bar dan 0.5 gr di hari ke-4 untuk digester dC , nyala api dominan biru di setiap digester.

Salah satu sumber energi yang dapat menghasilkan listrik ramah lingkungan adalah tenaga air. Turbin air memiliki berbagai macam tipe yang digunakan sesuai dengan keadaan aliran air. Turbin tipe savonius digunakan untuk mengembangkan sumber energi air ini, yang memiliki daerah aliran sempit dan kecepatan aliran air rendah. Salah satu jenis turbin tersebut adalah turbin savonius, yang utamanya digunakan untuk memanfaatkan energi angin untuk kemudian diaplikasikan pada pembuatan turbin air. Penelitian ini bertujuan untuk mengetahui nilai dan pengaruh dari jumlah dan sudut blade pada distribusi tekanan dan kecepatan pada turbin. Penelitian dilakukan dengan membuat model dan menggunakan software simulasi Solidworks Flow Simulation 2020. Pada distribusi kecepatan, rata-rata paling tinggi terjadi pada turbin 2 sudu dengan sudut blade 135° yaitu 1,437 m/s. Sedangkan yang paling rendah terjadi pada turbin 4 sudu dengan sudut blade 90° yaitu 1,420 m/s. Pada turbin 2 sudu dengan sudut blade 135° memberikan perbedaan distribusi rata-rata tekanan paling tinggi yaitu 101.338,74 Pa, sedangkan turbin dengan jumlah 4 sudu dengan sudut blade 135° memberikan perbedaan distribusi rata-rata tekanan paling rendah yaitu 101.333,21 Pa.