With ever-increasing consumption and pollution of our limited water resources, water scarcity has been brought rising levels of public concern on a global scale. However, this worsening situation could be alleviated through sustainable water reuse schemes, which include using suitable wastewater treatment technologies to treat and reclaim wastewater. Starting from the last century, anaerobic wastewater treatment technology has been recognized as a more promising alternative to conventional aerobic bioprocesses due to its prime advantages in pollution reduction, net energy production (methane generation) and sludge minimization. To date, anaerobic treatment processes have been successfully utilized for treating agricultural and industrial sewages, particularly in the mesophilic or thermophilic temperature conditions.