[Natalia Bourenane]

@AzuraAssociates.Deidre @azuraassociates_trisha Let me know if you are able to provide some comments?

[Peter]

The answer is feedstock dependant and in short thermal hydrolysis processes that use heat and pressure to break up cells can be worth considering where digester solids are costly to dispose of and feedstocks are slow to break down.

For recalcitrant feedstocks like waste activated sludge and agricultural residues it can get a 15% improvement in gas and in solids destruction.

Anecdotally, most commercial digesters processing manure or food waste have looked at it, done the financial analysis, and determined that the capital and energy cost do not justify the small increase in gas production. Municipal digesters use it because biosolids are costly to dispose of and it can reduce the amount of solids they need to truck away.

Biological processes like an acidogenic thermophilic hydrolysis tank do not generally increase biogas production, but can shorten stable retention times by a few days depending on the feedstock.