Fractionating various nutrient ions for resource recovery from swine wastewater using simultaneous anionic and cationic selective-electrodialysis.

Different from current nutrient recovery technologies of recovering one or two nutrient components (PO or NH) from wastewater, this study aimed to fractionate various nutrient anions and cations simultaneously, including PO, SO, NH, K, Mg and Ca, into several streams. The recovered streams could be further paired together to produce high-value products. A novel electrodialysis process was developed by integrating monovalent selective anion and cation exchange membranes into an electrodialysis stack.

Fractionating magnesium ion from seawater for struvite recovery using electrodialysis with monovalent selective membranes.

As the consumption of global phosphorus reserves accelerates, recovering phosphorus as struvite (MgNHPO·6HO) from wastewater is an important option for phosphorus recycling. However, magnesium source is one of the major limiting factors for struvite recovery. In this work, different from previous studies where seawater was used directly as magnesium source in struvite precipitation, an electrodialysis stack equipped with monovalent selective cation-exchange membranes was designed to fractionate Mg from seawater for struvite recovery.

Stevia-based sweeteners as a promising alternative to table sugar: The effect on Listeria monocytogenes and Salmonella Typhimurium growth dynamics.

Sugar is commonly substituted with stevia-based products in food industry and in our daily-life. This substitution results in a change in food product characteristic formula and properties that may affect the growth dynamics of food pathogenic and spoilage bacteria. This work studies the effect of table sugar (TS), laboratory sucrose (LS), commercial stevia (St) and steviol glycosides (SG) on the growth dynamics of Salmonella Typhimurium and Listeria monocytogenes.

Tolerance of Chemoorganotrophic Bioleaching Microorganisms to Heavy Metal and Alkaline Stresses.

The bioleaching potential of the bacterium Bacillus mucilaginosus and the fungus Aspergillus niger towards industrial residues was investigated by assessing their response towards various heavy metals (including arsenic, cadmium, cobalt, chromium, nickel, lead, and zinc) and elevated pH. The plate diffusion method was performed for each metal to determine the toxicity effect. Liquid batch cultures were set up for more quantitative evaluation as well as for studying the influence of basicity.

Performance analysis and optimization of autotrophic nitrogen removal in different reactor configurations: a modelling study.

The autotrophic nitrogen removal process (partial nitritation combined with the Anammox process) is a new and sustainable nitrogen removal technique for nitrogen-rich streams. A modelling study has been performed to define optimal process conditions (temperature, oxygen supply, pH and biomass retention) and to investigate the influence of chemical oxygen demand, nitrogen loading rate and hydraulic retention time on three alternative reactor configurations: a single oxygen-limited partial nitritation reactor, a single Anammox reactor, and a combination of partial nitritation and Anammox in a single reactor. The model applied was compared to experimental data from the literature and gave good agreement for all three reactor configurations.