EFFECTS OF STRONG ACID AND IONIC MATERIALS ON MICROWAVE-ASSISTED
THERMO-CHEMICAL HYDROLYSIS OF CATTLE MANURE
Jeongmin Lee, Jaeho Lee, Hyanggi Kim, Sanghoon Lee, Youngwoo Kim, Imgyu Byun and
Taejoo Park
Department of Civil and Environmental Engineering, Pusan National University, 63beon-gil,
Geumjeong-gu, Busan, Korea
Abstract
Microwave (MW) uses electrical energy. A catalytic material added MW hydrolysis is an effective
way of reducing electricity consumption and enhancing the hydrolysis of cattle manure. In this study,
catalytic materials, such as H2SO4 as the strong acid and NaCl as the ionic material, were applied to
enhance the hydrolysis of cattle manure. Food wastewater (FWW) was also applied as the ionic
material because of its high contents of NaCl and other ions such as K
+, NH
4
+, NO
3
-. After catalysts added MW-assisted
thermo-chemical hydrolysis, the maximum increases of SCOD
release/TCOD
initial ratio were 0.064 for H
2SO
4, 0.050 for
NaCl and 0.068 for FWW. And the SCOD
release/TCOD
initial ratio of FWW addition was 1.4 times higher than that with
NaCl addition at a MW power of 800 W and target temperature of 40°C. The specific SCOD increase per energy
consumption (mgSCOD/kJ) was 169.6 for H2SO4, 132.5 for NaCl and 180.2 for FWW. In biochemical methane
potential tests, methane productions of H
2SO
4 and FWW addition were 1.25 times and 1.30 times higher than that with
MW only assisted hydrolysis. Therefore, FWW was found to be good agent for enhancing the MW efficiency.
Keywords: Cattle manure, Microwave, Hydrolysis, Pretreatment, Chemical agent.