Explore the vast range of titles available.

Biogas technology is rapidly gaining market penetration, and the type of digesters employed in the harnessing of the biogas from biodegradable waste is crucial in enhancing the total viable bacteria counts. This study focused on the exploration of input parameter (number of days, daily slurry temperature, and pH) and target (total viable bacteria counts) datasets from anaerobic balloon digester charged with cow manure using data acquisition system and standard methods. The predictors were ranked according to their weights of importance to the desired targets using the reliefF test. The complete dataset was randomly partitioned into testing and validated samples at a ratio of 60% and 40%, respectively. The developed non-linear regression model applied on the testing samples was capable of predicting the yield of the total viable bacteria counts with better accuracy as the determination coefficient, mean absolute error, and p-value were 0.959, 0.180, and 0.602, respectively, as opposed to the prediction with the multiple linear regression model that yielded 0.920, 0.206, and 0.514, respectively. The 2D multi-contour surface plots derived from the developed models were used to simulate the variation in the desired targets to each predictor while the others were held constant.

Flexible balloon biogas plant based on kitchen waste was designed and installed for environmental-friendly disposal of around 250 kg waste generated per day in the kitchen of student mess at Sainik School, Chittorgarh, Rajasthan. The digester balloon having volume of 25 m3 was fabricated with high tenacity rubberized nylon fabric coated with hypalon on outer and neoprene on inner surface. A stirring unit was provided for mixing the digested slurry inside the digester with the compressed biogas. Average biogas generated was 0.0439 m3.kg−1 dry matter having methane and carbon di-oxide about 67.70% and 32.30%, respectively.

Access to clean cooking technologies is crucial for achieving SDG7 for remote households in small Pacific Islands like Fiji and for developed countries alike. Many small households in Fiji still rely on traditional biomass for cooking. This study explores the environmental sustainability and clean cooking potential of the Home Biogas 2.0 flexible balloon digester installed at Kamil Muslim College in Ba, Fiji. Comparative bench experiments were also performed. The bench-scale experiments produced higher biogas yields than the digester trials, with optimal outputs recorded from fresh cow dung (541 mL of cumulative biogas) and vegetable waste excluding rice (125 mL). When scaled, annual energy production from fresh cow dung reached 4644.64 MJ, equivalent to replacing 7.82 standard LPG cylinders, while vegetable waste produced 3763.76 MJ, offsetting 6.34 cylinders. Notably, biogas from cow dung exceeded the estimated annual household cooking demand of 3840 MJ for a family of four persons. The biogas produced from fresh cow dung provided an average cooking duration of 1 h 29 min, while biogas from vegetable waste lasted for 1 h 21 min. The economic analysis indicated that combining liquid digestate, used as biofertiliser, and biogas from cow dung resulted in the highest financial return, with a 67% Internal Rate of Return, a Net Present Value of $12,364.30, a Benefit Cost Ratio of 5.12, and a Discounted Payback Period of 1.28 years. This indicates the potential of Home Biogas 2.0 as a climate-smart technology that integrates renewable energy production, waste reduction, and sustainable agriculture, making it particularly suitable for rural and remote communities.

Tempeh is a traditional soybean product originating from Indonesia. Tempeh is a high-protein food, which costs less per unit than other animal protein sources. However, the Tempeh industry will produce waste with this process. Tempeh production process requires a lot of water to boil, soak, and wash soybean skin. The research problem is that the practice of Tempeh industry has not managed wastewater well, which has the potential to cause the quality of tempeh industrial wastewater to exceed quality standards and cause negative impacts on the environment and society living around the industry, so alternatives are needed to improve wastewater management. The alternative is to convert liquid waste into renewable energy. It refers to the SDGs agenda for seven objectives (7) to improve clean energy research and technology, including renewable energy, energy efficiency, and sophisticated and clean fossil fuel technology. Biogas is a type of biofuel that comes from living things and renewable energy. This research aimed to determine the type of biogas that is appropriate for small-scale industries by utilizing Tempeh liquid waste with a mixture of household organic waste. The results showed that the biogas digester balloon is the type that is suitable for small scale industries. The selection of balloon digester is reviewed from the technical aspects, economic aspects, environmental aspects, and social aspects. Biogas is the right technology to convert tempeh waste into energy so that it can obtain economic and environmental benefits.