2.5. Calculation methods
2.5.1. Hydrolysis rate and acidogenesis rate
The total COD conversion ratio of the hydrolysis and acidifica-
tion can be calculated according to soluble COD (SCOD), CODVFA and
CODlactic acid, respectively. These can be expressed as the product
divided by the influent COD in each reactor. All calculations were
determined by previous research and the following equations were
used following equations (Chu et al., 2012):
HydrolysisðCODÞ¼ SCOD
TCODin
(1)
AcidogenesisðCODÞ¼ CODVFA þ CODlactic acid
TCODin
(2)
where, TCODin is the total COD of the influent.