The ______________ of cow dung yields gobar gas?
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Answer: A. Fermentation
Explanation
Microorganisms ferment organic matter in cow dung without oxygen to produce biogas. Fermentation breaks down complex biomass into methane and carbon dioxide gases. This biological process operates efficiently inside sealed anaerobic digester tanks. Fermentation relies on specialized methanogenic bacteria acting on slurry mixtures. Cow dung provides a balanced mixture of organic carbon and bacterial nutrients. Temperature and pH control optimize gas production rates in biogas plants.
Rural households utilize fermented cow dung gas for clean cooking fuel supplies. The leftover digested slurry serves as a high-quality organic agricultural fertilizer. This renewable technology provides sustainable energy access in developing regions. Oxidation requires oxygen and would not produce combustible methane gas. Hydrogenation involves high-pressure catalytic addition of hydrogen, not biological digestion. Stating none of these is incorrect because fermentation is the exact biological mechanism.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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