Decentralized high-strength wastewater treatment using a compact aerobic baffled bioreactor.

Decentralized wastewater treatment is a potential solution to the economic and sustainability issues associated with current wastewater infrastructure requirements for rural and expanding urban settings. However, wastewater produced from small-scale operations (domestic, industrial, agricultural, defense, etc.) are often found to have higher pollution concentrations than municipal wastewater and is referred to as "blackwater" in the study.

High-rate anaerobic treatment of digestate using fixed film reactors.

The effluent stream of the anaerobic digestion processes, the digestate, accommodates high residual organic content that needs to be further treated before discharge. Anaerobic treatment of digestate would not only reduce the residual organic compounds in digestate but also has a potential to capture the associated biogas. High-rate anaerobic reactor configurations can treat the waste streams using lower hydraulic retention times which requires less footprint opposed to the conventional completely stirred tank reactors.

Volatile Fatty Acid Production from Anaerobic Digestion of Organic Residues.

Short chain volatile fatty acids (VFAs) from acetic acid (C2) to valeric acid (C5) are important starting chemicals for chemical industry. The production of VFAs from rejected resources (organic residues) using self-sustaining technologies has an exciting potential in supporting the US chemical industry to achieve the goal that 20% of chemicals produced in the USA will be bio-based. Acidogenic anaerobic digestion as a robust, well-established, and versatile biological technology can be applied as an alternative approach for the valorization of organic residues (municipal, agricultural, and industrial wastes) by the production of VFAs.

Modification of a conventional anaerobic digester for improving the effluent and sludge characteristics.

The aim of this study was to enrich the composition of anaerobic digester sludge in terms of nitrogen and phosphorus by struvite (MgNH4PO4) formation. Waste activated sludge was anaerobically digested in batch reactors under the conditions that the minimum stoichiometric requirement for struvite formation was satisfied in all reactors. For this purpose, different amounts of magnesium (Mg2+) and phosphate (PO4(3-)) ions were added initially to the batch reactors.

Recovery of acids from anaerobic acidification broth by liquid-liquid extraction.

In this study, anaerobic acidification of sugar beet processing wastes and subsequent liquid-liquid extraction of produced fermentation metabolites were investigated. The aim of extraction experiments was to asses the influence of pH and extractant (trioctylphosphine oxide (TOPO) in kerosene) concentrations on the recovery of volatile fatty acids (VFAs) from fermentation broth. The effect of TOPO in kerosene concentration was as crucial as the effect of pH on the recovery of VFAs via extraction.