Acute inhibition of hospital and medical laboratory wastewater on activated sludge.

Sustainable operation is an essential challenge in many municipal wastewater treatment plants. Among many types of wastewater mixed in a sewer, healthcare wastewaters need special attention due to their hazardous substance content, which can be toxic to activated sludge. This study compared the acute inhibitory effects of healthcare wastewaters (HW) and medical laboratory wastewater (MLW) on conventional activated sludge (CAS) and membrane bioreactor (MBR).

Medical laboratory wastewater treatment by electro-fenton process: Modeling and optimization using central composite design.

Medical laboratory wastewaters arising from diagnosis and examination units show highly toxic characteristic. Within the scope of the study, removal of the wastewater's toxicity and increasing BOD /COD ratio of the medical laboratory wastewaters through electro-Fenton (EF) process were investigated. In the study, central composite design was applied to optimize the process parameters of EF for COD, BOD , and toxicity unit (TU) removal.

Fouling mechanisms of membrane filtration of mixed microalgal biomass grown in wastewater.

Membrane fouling mechanisms of the filtration of a mixed-culture microalgal biomass grown in real wastewater were investigated using crossflow filtration experiments. The results of flux measurements, scanning electron microscopy (SEM) and atomic force microscopy (AFM) analyses for three membranes, two microfiltration (PES01 and PES003) and one ultrafiltration (UC030), showed that the UC030 membrane may be more appropriate for microalgae harvesting due to its higher steady flux rate and lower flux reduction during filtration compared to the initial flux (44% for UC030, compared to 86% for PES01 and 79% for PES003). It was also observed that the membrane resistance due to concentration polarization was the dominant membrane resistance in this study for all three membranes, constituting about 67%, 61% and 51% for PES01, PES003, and UC030, respectively.

Fate of proteins and carbohydrates in membrane bioreactor operated at high sludge age.

The paper evaluated the fate of proteins and carbohydrates in the course of substrate removal by membrane bioreactor (MBR), which was used for the biological treatment of black and grey water components of a controlled decentralized residential area. The MBRs were operated at a high sludge age of 60 days to better observe the magnitude of soluble residual products. Both groups were detected in the raw wastewater and represented 15% of the soluble chemical oxygen demand (COD) content for black water and 9% for grey water.