Week 5 - Innovation in Biogas Systems

Question 1

How can the slowest reaction (2) be sped up in the AD process

Answer 1

A conductive material is added so the gibbs free energy is negative so it happens. same output as usual with 5H+ and 4e-
Know the image and formula

Question 2

How to fix a pH imbalance on an AD

Answer 2

Add Graphene or a base and the system recovers. Grpahene also acts as the electron transfer material

Question 3

What is used instead of graphene in AD and why

Answer 3

biochar (Pure carbon) as graphene is very expensive. Biochar has good electorn transfer so increases the biogas yield.

Question 4

How is a biochar formed from whiskey by products

Answer 4

Draff at 700’C makes good biochar.

Question 5

How can we meet demand for water for electrolysers using wastewater.

Answer 5

Use biochar as activated carbon to scrub the waste water and make clean water to split into H2. Promote circular economy

Question 6

What happend when an modified electrode was put in the AD.

Answer 6

1 Volt 68% increase in methane, better than then electrode and biochar.
Anode broke down more feedstock into VFAs. At cathode CO2 reacted with electron and formed CH4.

Question 7

How can biogas be upgraded as per the microalage route

Answer 7

Digestate fed into bubble column. Algae react with CO2 to form bicarbonate. biomethane at the top. Microalage cultivation. €10,000/tonne microalgae

Question 8

Mckinsey report in 2019

Answer 8

they said biogas is too expensive to do. Was stupid. jerry did his own thing then and proved it is good, will make money back in the long run