TY - JOUR
T1 - Temperature susceptibility of a mesophilic anaerobic membrane bioreactor treating saline phenol-containing wastewater
AU - Muñoz Sierra, Julian D.
AU - Wang, Wei
AU - Cerqueda-Garcia, Daniel
AU - Oosterkamp, Margreet J.
AU - Spanjers, Henri
AU - van Lier, Jules B.
PY - 2018
Y1 - 2018
N2 - This study examined the temperature susceptibility of a continuous-flow lab-scale anaerobic membrane bioreactor (AnMBR) to temperature shifts from 35 °C to 55 °C and its bioconversion robustness treating synthetic phenolic wastewater at 16 gNa+.L−1. During the experiment, the mesophilic reactor was subjected to stepwise temperature increases by 5 °C. The phenol conversion rates of the AnMBR decreased from 3.16 at 35 °C to 2.10 mgPh.gVSS−1.d−1 at 45 °C, and further decreased to 1.63 mgPh.gVSS−1.d−1 at 50 °C. At 55 °C, phenol conversion rate stabilized at 1.53 mgPh.gVSS−1.d−1 whereas COD removal efficiency was 38% compared to 95.5% at 45 °C and 99.8% at 35 °C. Interestingly, it was found that the phenol degradation process was less susceptible for the upward temperature shifts than the methanogenic process. The temperature increase implied twenty-one operational taxonomic units from the reactor's microbial community with significant differential abundance between mesophilic and thermophilic operation, and eleven of them are known to be involved in aromatic compounds degradation. Reaching the upper-temperature limits for mesophilic operation was associated with the decrease in microbial abundance of the phyla Firmicutes and Proteobacteria, which are linked to syntrophic phenol degradation. It was also found that the particle size decreased from 89.4 μm at 35 °C to 21.0 μm at 55 °C. The accumulation of small particles and higher content of soluble microbial protein-like substances led to increased transmembrane pressure which negatively affected the filtration performance. Our findings indicated that at high salinity a mesophilic AnMBR can tolerate a temperature up to 45 °C without being limited in the phenol conversion capacity.
AB - This study examined the temperature susceptibility of a continuous-flow lab-scale anaerobic membrane bioreactor (AnMBR) to temperature shifts from 35 °C to 55 °C and its bioconversion robustness treating synthetic phenolic wastewater at 16 gNa+.L−1. During the experiment, the mesophilic reactor was subjected to stepwise temperature increases by 5 °C. The phenol conversion rates of the AnMBR decreased from 3.16 at 35 °C to 2.10 mgPh.gVSS−1.d−1 at 45 °C, and further decreased to 1.63 mgPh.gVSS−1.d−1 at 50 °C. At 55 °C, phenol conversion rate stabilized at 1.53 mgPh.gVSS−1.d−1 whereas COD removal efficiency was 38% compared to 95.5% at 45 °C and 99.8% at 35 °C. Interestingly, it was found that the phenol degradation process was less susceptible for the upward temperature shifts than the methanogenic process. The temperature increase implied twenty-one operational taxonomic units from the reactor's microbial community with significant differential abundance between mesophilic and thermophilic operation, and eleven of them are known to be involved in aromatic compounds degradation. Reaching the upper-temperature limits for mesophilic operation was associated with the decrease in microbial abundance of the phyla Firmicutes and Proteobacteria, which are linked to syntrophic phenol degradation. It was also found that the particle size decreased from 89.4 μm at 35 °C to 21.0 μm at 55 °C. The accumulation of small particles and higher content of soluble microbial protein-like substances led to increased transmembrane pressure which negatively affected the filtration performance. Our findings indicated that at high salinity a mesophilic AnMBR can tolerate a temperature up to 45 °C without being limited in the phenol conversion capacity.
KW - AnMBR
KW - Mesophilic
KW - Microbial community
KW - Phenol
KW - Salinity
KW - Temperature susceptibility
UR - http://resolver.tudelft.nl/uuid:388fbdaa-82e0-4e93-92a5-9a4ff2b5d175
UR - http://www.scopus.com/inward/record.url?scp=85053083746&partnerID=8YFLogxK
U2 - 10.1016/j.chemosphere.2018.09.023
DO - 10.1016/j.chemosphere.2018.09.023
M3 - Article
AN - SCOPUS:85053083746
VL - 213
SP - 92
EP - 102
JO - Chemosphere
JF - Chemosphere
SN - 0045-6535
ER -