Mosley Cullen (sparkskill28)

Nowadays, increasing attention has been drawn to biological valorization of organic wastes. Wherein, propionic acid-rich fermentation (PARF) has become a focal point of research. The objective of this review is to make a thorough investigation on the potential of PARF production and give future outlook. By discussing the key factors affecting PARF including substrate types, pH, temperature, retention time, etc., and various improving methods to enhance PARF including different pretreatments, inoculation optimization and immobilization, a comprehensive summary on how to achieve PARF from organic waste is presented. Then, current application of PARF liquid is concluded, which is found to play an essential role in the efficient denitrification and phosphorus removal of wastewater and preparation of microbial lipids. Finally, the environmental performance of PARF production is reviewed through life cycle assessment studies, and environmentally sensitive sectors are summarized for process optimization, providing a reference for waste management in low carbon scenarios.Simultaneous nitrification/denitrification (SND) can efficiently deplete NH4+ by using air-exposed biocathode (AEB) in bioelectrochemical reactors. However, the fluctuation of wastewater adversely affects the functional biofilms and therefore the performance. In this work, four up-flow bioelectrochemical reactors (UBERs) with some novel inocula were investigated to improve domestic wastewater treatment. The UBERs exhibited favorable removal of chemical oxygen demand (COD, 95%), NH4+-N (99%), and total nitrogen (TN, 99%). The maximum of current (2.7 A/m3), power density (136 mW/m3) and coulombic efficiency (20.5%) were obtained. AMG-193 Cyclic voltammetry analysis showed all the electrodes were of diversified catalytic reactions. Illumina pyrosequencing showed the predominant Ignavibacterium, Thauera, Nitrosomonas, Geminicoccus and Nitrospira were in all electrodes, contributing functional biofilms performing SND, comammox, and bioelectrochemical reactions. FAPROTAX analysis confirmed twenty-one functional groups with obvious changes related to chemoheterotrophy, respiration/oxidation/denitrification of nitrite and nitrate. Comfortingly, such novel diversified consortia in UBERs enhance the microbial metabolisms to treat domestic wastewater.Chemically enhanced primary treatment (CEPT) is an emerging sewage treatment strategy due to its high efficiency and small land requirement. CEPT sludge can be easily dewatered and used for energy recovery through incineration. However, with large amount of reusable nutrients (40% organic carbon, 23% lipids, and 17% protein), the value of CEPT sludge may have been underestimated. In this study, the biorefinery potential of CEPT sludge has been proven via production of 28.9 g/L ethanol or 50.3 g/L lactic acid (LA) or 1.43 filter paper unit (FPU)/mL cellulase from 10 g of CEPT sludge experiment. Inhibition on cell growth and potential inhibitors from plasticizers, pharmaceuticals, and surfactants were determined. Nevertheless, production titer was not affected or performed even better than the non-inhibitors controls. CEPT sludge showed significant potential in biochemical conversion, and the related products may offer an opportunity to support wastewater treatment toward sustainability and carbon neutrality.Layered inoculation of anaerobic digestion (AD) and anammox granular sludges was performed for fast start-up of anammox using an expanded granular sludge bed (EGSB) reactor (R1) with the cell lysis phase and the lag phase being shortened. The maximum nitrogen loading rate (NLR) and nitrogen removal rate (NRR) of R1 were 11 kg N/m3 d and 9.9 kg N/m3 d on day 42, respectively. The domesticated AD granular sludge on the upper layer was collected to another EGSB reactor (R2) to investigate its anammox activity. The results showed that AD granular sludge in R1 had anammox activity and could be cultured into anammox granular sludge.