Table 6.

Average values of OLR, volumetric and specific methane production, and mass balance for conversion of removed _totalCOD into methane during operation of UASB reactors (R1 and R2) for vinasse treatment.

Attributes UASB reactor	OLR (g totalCOD (L d)−1)	Volumetric methane production* (L CH4 (L d)−1)		Specific methane production* (L CH4 (g totalCOD removed)−1)		Mass balance (removed totalCOD converted into CH4)*
			vc		vc	(%)
R1	0.2–2.5	0.087	80	0.133	48	58
2.5–5.0	0.440	43	0.175	30	51
5.0–7.5	0.597	18	0.181	20	48
7.5	0.554	4	0.172	35	48
R2	0.0–2.5	0.120	57	0.145	33	65
2.5–5.0	0.550	34	0.179	22	52
5.0–7.5	0.829	21	0.185	14	53
7.5–11.5	0.989	15	0.138	25	39
11.5	0.938	22	0.115	30	42

Values adjusted for standard temperature and pressure (STP) (0 °C and 1 atm).

OLR, organic loading rate; _totalCOD, total chemical oxygen demand; vc, variation coefficient (%).