Figure 2
Changes in related physical and chemical indices of the anaerobic digestion system. (a) pH; (b) organic acid concentration; (c) COD concentration; (d) ammonia–nitrogen concentration.
Figure 2 | Scientific Reports
Changes in related physical and chemical indices of the anaerobic digestion system. (a) pH; (b) organic acid concentration; (c) COD concentration; (d) ammonia–nitrogen concentration.
