Table 6.

Total VFA yield, ammonium nitrogen concentration and gas yield during anaerobic digestion of food waste at different controlled pH and ISR.

	Total VFA yield		Ammonium nitrogen concentration (mg/L)	Gas yield day 12 (mL/g VS)			pH	ORP
ISR/pH	Day 12	Day 14	Day 14	H2	CH4	CO2	Day 14	Day 14
1:1/pH 4	0.51	0.41	750	169.1	0.6	0.1	3.99	144.5
1:1/pH 5	0.58	0.58	800	122.9	3.3	0.4	4.98	88
1:1/pH 6	0.57	0.17	900	56.3	6.2	0.8	6.85	−19
1:3/pH 4	0.22	0.17	700	0.1	0.09	0.0	3.95	147
1:3/pH 5	0.58	0.48	875	70.0	0.4	0.1	4.96	89
F/1:3/pH 6	0.81	0.51	1225	51.3	0.4	0.0	5.96	32.5