C6 Anaerobic Digestion

Question 1

concept anaerobic digestion

Answer 1

• conversion of organic waste in absence of O2
• use bacteria as catalyst
• has 4 stage occur simultaneously and synergically

Question 2

final product

Answer 2

• energy rich biogas (CH4 & CO2)
• by product- nutrient digestate used as fertilizer

Question 3

4 process anaerobic digestion

Answer 3

1. hydrolysis (surface reaction) -break down long chain polymer to monomer
2. acidogenesis
3. acetogenesis
4. methanogenesis

Question 4

example bacteria used in anaerobic digestion

hyrolysis & fermenting reaction

Answer 4

• bacteriodes
• lactobactillus

Question 5

example bacteria used in anaerobic digestion

acetogenic reaction

Answer 5

• desulfovibrio
• syntrophomonas

Question 6

example bacteria used in anaerobic digestion

methanogenesis reaction

Answer 6

• M.ruminantium
• M.bryantii

Question 7

factors affecting biogas production

Answer 7

1. solid content&dilution
2. C/N element ratio
3. pH
4. temperature
5. loading rate
6. retention time
7. toxicity
8. mixing/agitation
9. pathogen

Question 8

what is digestate

Answer 8

• residue material that remain following the completion of digestion process
• consist mixture of partially decompose organic matter,nutrient and water
• rich in nutrient (N,P,K) that suitable for agriculture

Question 9

obstacle to further develop anaerobic digestion

Answer 9

• realibility
• invesment uncertainty