Wet Oxidation Pre-Treatment – the Way To Improve Economics of Energy Production From Manure?

Throughout recent years, several physical, chemical and biological pretreatment methods have been tested with limited success in order to increase hydrolysis of the lignocellulose structure of manure fibers (Fan et al., 1982; Gharpuray et al., 1983; Grethlein, 1984; Hartmann et. al. 2000; Hobson and Wheatley, 1993). The combination of high temperature and pressure, together with the addition of oxygen in the wet oxidation process, has shown a superior potential for increasing the hydrolysis of lignocellulosic biomass with subsequent ethanol fermentation. In the present study the wet oxidation process was tested as pretreatment for increasing the biogas yield of the fiber fraction of manure. The wet oxidation pretreatment in combination with solid liquid separation of manure by using either chemical precipitation or decanter centrifuge (Møller et al., 2004) could be a promising option for a significant increase of the economical benefit in the AD treatment of manure.