Anaerobic Digestion Under Environmentally Stressed Conditions

Anaerobic digestion can tackle both challenges of environmental pollution and energy crisis simultaneously and has been commonly applied for renewable energy recovery in the form of biogas from organic waste. However, the performance of anaerobic digestion can be affected by environmental stressors, including both disturbance and inhibition. Typically, three types of inhibition can occur, including the osmotic pressure induced by ions, surface layer formation preventing efficient substrate diffusion, and enzyme inhibition by transferred inhibitors. Microorganisms in anaerobic digestion systems can adopt different strategies responding to stressed conditions, such as microbial morphology adaptation, microbial physiology response, and microbial community acclimatization. The redundancy, resistance, and resilience are proposed as the strategy for improving system stability of anaerobic digestion, including under environmentally stressed conditions.