Origin of heat-induced structural changes in dissolved organic matter

Organic fouling behavior in direct contact membrane distillation

“…The HA concentration in the feed solution did not increase proportionally with the VCF and it was also not detected on the membrane foulant, the results suggest that the HA compound was disaggregated as BB-HA and LMW-HA organics. The HA compound disaggregating tendencies with increased temperature has been highlighted in the previous studies [14,15,30]. These studies used methods such as dynamic light scattering and ultrasonic velocimetry and observed the decrease of HA molecular size due to the disaggregation of HA aggregates by thermal agitation.…”

“…It has actually been demonstrated that humic compounds adsorbed more favorably onto hydrophobic membranes [13]. Further, the thermal heating in MD may influence humic characteristics, whereby previous studies have observed humic disaggregation to lower molecular size humics and other organics under thermal condition [14,15]. However, MD studies have highlighted that fouling by humic substances was not severe as compared to pressure-driven membrane processes, primarily due to the vapor pressure operated application [10,16,17].…”

Interaction of humic substances on fouling in membrane distillation for seawater desalination

“…It is also evident that thermal heating in MD may also influence the characteristics of humic substances. Under thermal condition, several studies have observed the disaggregation of humic substances to lower molecular sized humics and other organics [18,19]. This aspect has not been evaluated in detail in MD organic fouling studies.…”

A review on fouling of membrane distillation

“…Similarly, in MD studies, high flow velocity will reduce the loose crystal deposit that has accumulated on the membrane surface. However, it is important to point out that in MD, the pressure of high flow velocity will increase the risk to membrane wetting as shown by other studies [117].…”