A New Concept of Digestion with Thermal Hydrolysis: A Pathway towards Energy Sufficiency of Wastewater Treatment Plants

摘要

Thermal biosolids hydrolysis has been recognized as one of the most effective ways to enhance biogas production and solids destruction in the anaerobic digestion system. Recently, Veolia has improved the thermal hydrolysis process (THP) from the batch operation to the continuous operation. Exelys? is a thermal hydrolysis (160°C; 10 bar) process specifically designed for continuous operation, which is more automated, reliable and robust. Through its innovative design and continuous operational configuration, Exelys? is highly effective in energy efficiency among the available processes for thermal biosoilds hydrolysis. Due to the unique characteristics of the hydrolyzed biosolids product, it is an ideal solution for significantly increasing the capacity of existing digestion systems. The continuously designed and operated thermal hydrolysis process (THP) —— Exelys? presents the following advantages: It's bearing a simple design with minimal infrastructure required on site; It's an innovative design that is protected by patent around the world; The entire steam needs could be covered by cogeneration; - The process could achieve 30% to 40% more biogas production; - Producing 25% to 35% less bio-solids; - Achieve the enhanced pathogen destruction (pasteurization). A full scaled installation of the Exelys? process has been tested in Hillerod, Denmark, since October 2010. This paper will present the performance of the installed Exelys?-LDL process in the reduction of sludge volume, sludge sanitation and energy recovery efficiency. This test has demonstrated that the Exelys? will present a bright future in Chinese wastewater & sludge treatment market.