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Microbes in Human Welfare — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYMicrobes in Human Welfare4 Marks
Question
Explain structure and working of biogas plant with diagram.
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Answer


Image
→ 10-15 feet deep concrete tank is prepared for biogas plant.
→ This tank is fed by collected bio-waste and a slurry.
→ A floating cover is placed over the slurry.
→ Due to microbial activity (Methanogens) this slurry keeps rising as the gas is produced.
→ The biogas plant has an outlet.
→ This is connected to a pipe to supply biogas to nearby houses.
→ The spent slurry is removed through another outlet and may be used for as a fertiliser.
→ The biogas plants are more often built in rural areas.
→ The biogas thus produced is used for cooking and lighting.
→ In biogas plant, bacteria produce a mixture of gases from biogas such as carbon dioxide, methane and hydrogen.
→ These bacteria are collectively called as methanobacterium.

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