ABSTRACT
This chapter provides an overview of the high-solids (HS)-anaerobic digestion (AD) process, including process microbiology and design and operating parameters. It presents the trends in HS-AD implementation in Europe and the United States, along with critical economic, policy, and other factors needed for successful implementation of HS-AD systems. The chapter assesses the sustainability of HS-AD through a review of the life cycle assessment (LCA) literature related to the topic. In municipal and industrial waste management applications, AD technologies have been widely used for treating and recovering energy from high-strength wastewaters and organic sludge's. The four major microbial processes, or metabolic phases, of AD are: Hydrolysis, Acidogenesis, Acetogenisis, and Methanogenesis. The major operating parameters monitored in HS-AD can be separated into physical and chemical categories. Retention times in liquid (L)-AD are separated into two components: hydraulic retention time (HRT) and solids retention time (SRT).
