The performance and microbial community structure for treating lipids-rich kitchen waste slurry in mesophilic Anaerobic Membrane Bioreactor (m-AnMBR) and thermophilic AnMBR (t-AnMBR) were compared in this study. Higher Organic Loading Rate (OLR) of 12 kg-COD/(m³·d), better Chemical Oxygen Demand (COD) removal efficiency over 98%, stronger stability with Volatile Fatty Acids (VFAs)/alkalinity below 0.04, higher flux with 18 L/(m²·h) and lower Long Chain Fatty Acids (LCFAs) concentration of 550 mg/L were obtained in the m-AnMBR. Directly increasing temperature from 39 to 55 °C resulted in a collapse of the t-AnMBR. Acclimation via gradually increasing temperature made the t-AnMBR run successfully with lower OLR and COD removal efficiency of 7.5 kg-COD/(m³·d) and 96%. An obvious discrepancy of microbial community structure was presented between the m-AnMBR and t-AnMBR via the 16S rRNA gene sequence analysis. The Methanomethylovorans and Methanoculleus were dominant in the t-AnMBR instead of Methanobacterium and Methanothrix in the m-AnMBR.

In this study, pilot-scale vertical-flow constructed wetland (VFCW) and horizontal-flow constructed wetland (HFCW) were constructed to treat eutrophic water, and dissolved oxygen (DO) distributions, decontamination performances and key enzymes activities were compared under different influent loads. The influent load increase caused reductions of DO levels and removal efficiencies of chemical oxygen demand (COD), total nitrogen (TN), NH₄⁺−N and organic nitrogen, but it had no remarkable effect on the removal of NO₃⁻−N and total phosphorus (TP). The interior DO concentrations of VFCW were higher than those of HFCW, indicating a vertical hydraulic flow pattern was more conducive to atmospheric reoxygenation. The VFCW and HFCW ecosystems possessed comparable removal capacities for TN, NO₃⁻−N and TP. VFCW had a remarkable superiority for COD and organic nitrogen degradation, but its effluent NH₄⁺−N concentration was higher, indicating the NH₄⁺−N produced from organic nitrogen degradation was not effectively further removed in the VFCW system. The activities of protease, urease and phosphatase declined with the increasing depth of substrate layers, and they were positively correlated with DO concentrations. The enzymatic activities of VFCW were significantly higher than that of HFCW in the upper layers. Taken together, VFCW and HFCW presented a certain difference in operational properties due to the different hydraulic flow patterns.