13th International Congress on Biofuels and Bioeconomy
Ottawa, USA
Yaobin Zhang
Dalian University of Technology, China
Title: Adding waste scrap iron to enhance anaerobic digestion of sewage sludge and production of methane
Biography
Biography: Yaobin Zhang
Abstract
Anaerobic digestion is a slow process and easily go sour, inhibiting methane production. In this study, scrap iron was applied to accelerate anaerobic digestion of organic waste. When adding scrap iron into an anaerobic digester for treating sewage sludge, the sludge reduction increased by 12%, and methane production increased by 21.3%. Chemical iron corrosion had not increased H2 content of the biogas, but decreased H2 content by 85%, which was due to the stimulate of the growth of H2-utilizing methanogens that consumed H2 to forward the anaerobic respiration to process. Especially, rusty iron was more effective in enhancing sludge digestion. Compared with the clean scrap iron, the rusty scrap iron could further increase methane production by 29% and increase sludge reduction by 7.1%. Iron-reducing bacteria like Geobacter was enriched in the rusty scrap iron-added system, triggering a dissimilatory iron reduction which is capable of utilizing complex matters in the sludge as electron donor to help the sludge decomposition and anaerobic sludge digestion.