Novel ellipsoid-like granules exhibit enhanced anammox performance compared to sphere-like granules.

Anammox granular sludge (AnGS) serves as an important platform for cost-effective nitrogen removal from wastewater. Different to the traditionally sphere-like granules, a novel type of AnGS in a unique ellipsoid-like shape was obtained through enhancing shear force. The ellipsoid-like AnGS significantly exhibited a smaller aspect ratio (-25.

The evolution of calcified anaerobic granular sludge bed informs the deep insight into its agglomeration process.

Calcium-induced agglomeration of anaerobic granular sludge bed (AGSB) has become a critical factor in performance decline of calcified anaerobic reactors. However, the agglomeration process of AGSB and the underlying mechanisms remain unclear and elusive. This study delved into the evolution of calcified AGSB, and four typical states of normal AGSB (Nor-AGSB), calcified dispersed AGSB (Dis-AGSB), calcified dimeric AGSB (Dim-AGSB), and calcified polymeric AGSB (Pol-AGSB) were characterized.

The culprit for the declining performance of anaerobic reactors caused by calcification: Bioavailability deterioration.

Calcification is a critical challenge for achieving anaerobic reactors' high-efficiency. However, the aggregation caused by calcification at both granular sludge and reactor levels remain to be fully understood. Herein, this study investigated the characteristics of calcification in an anaerobic reactor (R) operated with high calcium-containing wastewater for over 200-day.

Ecological distribution of anaerobic granular sludge towards efficient anaerobic reactor.

Anaerobic reactors often underperform compared to expectations. To identify the key factors, an ecological anaerobic reactor (EAR) with vertical partitions was developed and compared to a physical anaerobic reactor (PAR) as the control. It was observed that EAR achieved a much higher organic loading rate (OLR) compared to PAR (>100 vs 45 kg/m·d).

Insights into the Superior Bioavailability of Biogenic Sulfur from the View of Its Unique Properties: The Key Role of Trace Organic Substances.

Elemental sulfur (S) is widely utilized in environmental pollution control, while its low bioavailability has become a bottleneck for S-based biotechnologies. Biogenic sulfur (bio-S) has been demonstrated to have superior bioavailability, while little is known about its mechanisms thus far. This study investigated the bioavailability and relevant properties of bio-S based on the denitrifying activity of with chemical sulfur (chem-S) as the control.

The removal of veterinary antibiotics in the high-rate anaerobic bioreactor: continuous and batch studies.

Veterinary antibiotics in swine wastewater has drawn great public attention. The removal processes of sulfamethizole (SMZ), enrofloxacin (ENR) and chlortetracycline (CTC) were investigated in the high-rate anaerobic process. The continuous experiments demonstrated that in 3 L working volume and with the organic loading rate 5 kg/(m·d) rised to 20 kg/(m·d), the average removal efficiencies of the high-rate anaerobic bioreactor for SMZ, ENR and CTC were 0, 54 and 100%, respectively.

Response of FANIR system to starvation stress: "Dormancy".

Anaerobic ammonium oxidation (Anammox) process has been successfully applied in the nitrogen removal from high-strength wastewaters. However, little information is available for its treatment of low-strength wastewaters. In this study, a Famine Anammox NItrogen Removal (FANIR) system was developed to investigate the effect of long-term substrate starvation at the low nitrogen concentration (the influent total nitrogen was set at ∼1 mg/L).

Surface convexity of anammox granular sludge: Digital characterization, state indication and formation mechanism.

Anammox granular sludge system is a promising biotechnology for nitrogen removal from wastewaters. The anammox granules possess the distinctive morphological features which can be developed as visible indicators for anammox process monitoring. In this study, the surface convexity of anammox granular sludge (AnGS) was systematically investigated for the first time.