TY - JOUR
T1 - Enhanced methane production using pretreated sludge in MEC-AD system
T2 - Performance, microbial activity, and implications at different applied voltages
AU - Joicy, Anna
AU - Seo, Hwijin
AU - Lee, Myoung Eun
AU - Kim, Dong Hoon
AU - Cho, Si Kyung
AU - Ahn, Yongtae
N1 - Publisher Copyright:
© 2022 Hydrogen Energy Publications LLC
PY - 2022/12/12
Y1 - 2022/12/12
N2 - Although various pretreatment methods are employed to promote sludge hydrolysis and thereby promoting methane production in the subsequent microbial electrolysis cell assisted anaerobic digestion (MEC-AD) system, the questions arise are, “which pretreatment method on waste activated sludge (WAS) maximises the sludge hydrolysis and what is the optimal applied voltage on anaerobic digestion (AD) to stimulates the direct interspecies electron transfer (DIET) performance and thereby accelerating the methane production fed with pretreated WAS?” was still unanswered. Herein, firstly, a series of pretreatment methods to hydrolyse and mineralise the organic matter of WAS was performed to evaluate solubilization efficiency and thereafter, the influence of different applied voltages (0.3 V, 0.6 V, and 0.9 V) on coupled MEC-AD reactors fed with pretreated WAS was investigated to apprehend the DIET promotion for methane production. The results indicated that in MEC-AD reactors, the methane yield increased by 27.2%, 44.8%, and 37.3% when the applied voltages were 0.3 V, 0.6 V, and 0.9 V, respectively. Therefore, the alkaline-thermal pretreatment (ATP) enhanced the sludge hydrolysis in WAS, followed by an applied voltage of 0.6 V in the MEC-AD reactor fed with pretreated WAS, enhanced methane production under DIET stimulation induced by the increased abundance of electroactive microorganisms (EAM) and the advanced electron transfer. Besides, the energy balance estimation validates that with an applied voltage of 0.6 V in MEC-AD could achieve higher net energy input.
AB - Although various pretreatment methods are employed to promote sludge hydrolysis and thereby promoting methane production in the subsequent microbial electrolysis cell assisted anaerobic digestion (MEC-AD) system, the questions arise are, “which pretreatment method on waste activated sludge (WAS) maximises the sludge hydrolysis and what is the optimal applied voltage on anaerobic digestion (AD) to stimulates the direct interspecies electron transfer (DIET) performance and thereby accelerating the methane production fed with pretreated WAS?” was still unanswered. Herein, firstly, a series of pretreatment methods to hydrolyse and mineralise the organic matter of WAS was performed to evaluate solubilization efficiency and thereafter, the influence of different applied voltages (0.3 V, 0.6 V, and 0.9 V) on coupled MEC-AD reactors fed with pretreated WAS was investigated to apprehend the DIET promotion for methane production. The results indicated that in MEC-AD reactors, the methane yield increased by 27.2%, 44.8%, and 37.3% when the applied voltages were 0.3 V, 0.6 V, and 0.9 V, respectively. Therefore, the alkaline-thermal pretreatment (ATP) enhanced the sludge hydrolysis in WAS, followed by an applied voltage of 0.6 V in the MEC-AD reactor fed with pretreated WAS, enhanced methane production under DIET stimulation induced by the increased abundance of electroactive microorganisms (EAM) and the advanced electron transfer. Besides, the energy balance estimation validates that with an applied voltage of 0.6 V in MEC-AD could achieve higher net energy input.
KW - Applied voltage
KW - DIET
KW - Methane yield
KW - Pretreatment
KW - Waste activated sludge
UR - http://www.scopus.com/inward/record.url?scp=85136129490&partnerID=8YFLogxK
U2 - 10.1016/j.ijhydene.2022.07.154
DO - 10.1016/j.ijhydene.2022.07.154
M3 - Article
AN - SCOPUS:85136129490
SN - 0360-3199
VL - 47
SP - 40731
EP - 40741
JO - International Journal of Hydrogen Energy
JF - International Journal of Hydrogen Energy
IS - 96
ER -