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The present study investigated the feasibility of using an integrated pilot-scale UASB and aerotank system for treating high-strength wastewater generated from a household rice paper manufacturing unit. The MLSS in the aerotank increased from 1.62 ± 0.06 to 3.23 ± 0.05 g/L over a 7-day period. The UASB achieved a removal efficiency of 69.2–82.2% for total suspended solids (TSS), 66.5–82.9% for chemical oxygen demand (COD), and 81.2–92.8% for biochemical oxygen demand (BOD5) while treating the rice paper production effluent over a 30-day period. Further, over a 20-week period, the UASB achieved removal efficiencies of 80.6–90.3% for TSS, 82.2–83.3% for COD, and 85.6–86.4% for BOD5. The aerotank achieved a removal efficiency of 89.0–94.1% for TSS, 94.5–95.5% for COD, 96.8–98.1% for BOD5, 91.8–95.4% for total nitrogen (TN), and 89.2–94.6% for total phosphorous (TP) during a period of 7 days. DNA sequence analysis indicated that the anaerobic sludge was predominantly populated by the Bacillussp. The findings demonstrated that the integrated pilot-scale UASB and aerotank system exhibited high removals of TSS, COD, and BOD5during the treatment of a high organic load-containing rice paper production effluent. The generation of biogas and the methane content of the biogas were also determined in the present study. The integrated pilot-scale UASB and aerotank system established in this study is affordable, has a small footprint, relatively simple installation and operational procedures, and it is suitable for treating wastewater from an individual small-scale rice paper production facility.

The vertical hard revetment can cause the disturbance in river flow with the results of destroyed features, degraded biodiversity, decreasing self-purification ability and deteriorated water quality. The current work is focused on the application of prefabricated porous concrete template covered on widespread vertical hard revetment for improving water purification, increasing biodiversity and decreased negative impact of hard concrete revetment to river quality. Six kinds of porous concrete with different void ratio, aggregate size and water cement ratio were prepared to investigate the compressive strength and water purification properties. A river simulator device was used to determine the water purification capacity of the porous concrete in flowing condition. Water quality purification mechanism of porous concrete was discussed thoroughly by the analysis of microbial community diversity. Results show that the compressive strength and water purification ability of porous concrete were higher when the void ratio, size of the aggregate material and water cement ratio were 30%, 10–20 mm and 0.3, respectively. Under the flow velocity of V = 0.03 m/s and hydraulic retention time of 6 d, the removal rates of M2biofilm for chemical oxygen demand (CODMn), ammonia nitrogen (NH3–N), nitrate nitrogen (NO3–N), total nitrogen (TN) and total phosphorus (TP) were 59.21%, 74.07%, 54.25%, 55.47% and 62.90%, respectively. Findings reveal that prefabricated porous concrete was efficient for river water purification. Porous concrete templates can be attached to a large number of microorganisms.