TY - JOUR
T1 - Long-term investigation of fouling of cation and anion exchange membranes in microbial desalination cells
AU - Ping, Qingyun
AU - Cohen, Barak
AU - Dosoretz, Carlos
AU - He, Zhen
PY - 2013/9/16
Y1 - 2013/9/16
N2 - The fouling of ion exchange membranes in microbial desalination cells (MDCs) was investigated through an eight-month operation. Multiple MDCs were set up by using cation (CEM), anion (AEM), and/or proton (Nafion) membranes. The MDCs exhibited relatively constant reduction of conductivity of artificial seawater during the testing period (46.3±6.3% in the CEM-MDC and 78.7±0.8% in the Nafion-MDC in an operating cycle). However, the current generation decreased from 99 to 56A/m3 in the CEM-MDC after 250days, and from 97 to 46A/m3 in the Nafion-MDC after 130days, indicating the presence of membrane fouling. Theoretically the MDCs removed 6.7-12.1 kg TDS/m3/d with a high charge transfer efficiency of 230-440%, suggesting that electric current was not the only factor to drive desalination; water dilution played an important role in conductivity reduction as well. It was observed that the AEM contained significant biofouling, resulting from wastewater and microbial growth on organic compounds migrating across the membrane, while the CEM had substantial inorganic scaling, mainly consisting of calcium and magnesium. The membrane resistance of the CEM increased more significantly than that of the AEM, indicating that CEM needs more maintenance during MDC operation.
AB - The fouling of ion exchange membranes in microbial desalination cells (MDCs) was investigated through an eight-month operation. Multiple MDCs were set up by using cation (CEM), anion (AEM), and/or proton (Nafion) membranes. The MDCs exhibited relatively constant reduction of conductivity of artificial seawater during the testing period (46.3±6.3% in the CEM-MDC and 78.7±0.8% in the Nafion-MDC in an operating cycle). However, the current generation decreased from 99 to 56A/m3 in the CEM-MDC after 250days, and from 97 to 46A/m3 in the Nafion-MDC after 130days, indicating the presence of membrane fouling. Theoretically the MDCs removed 6.7-12.1 kg TDS/m3/d with a high charge transfer efficiency of 230-440%, suggesting that electric current was not the only factor to drive desalination; water dilution played an important role in conductivity reduction as well. It was observed that the AEM contained significant biofouling, resulting from wastewater and microbial growth on organic compounds migrating across the membrane, while the CEM had substantial inorganic scaling, mainly consisting of calcium and magnesium. The membrane resistance of the CEM increased more significantly than that of the AEM, indicating that CEM needs more maintenance during MDC operation.
KW - Biofouling
KW - Ion exchange membrane
KW - Microbial desalination cell
KW - Scaling
KW - Wastewater
UR - https://www.scopus.com/pages/publications/84880966449
U2 - 10.1016/j.desal.2013.06.025
DO - 10.1016/j.desal.2013.06.025
M3 - Article
AN - SCOPUS:84880966449
SN - 0011-9164
VL - 325
SP - 48
EP - 55
JO - Desalination
JF - Desalination
ER -