Microbial reactors are provided for ammonium oxidation. Briefly, a reactor comprises a medium including an ammonium component and a Feammox bacterium and/or enzyme(s) thereof capable of oxidizing ammonium with electron transfer to an anode in contact with the medium. As described further herein, use of the anode as an electron acceptor can mitigate or overcome the disadvantages associated Fe(III) acceptor. In some embodiments, for example, ammonium oxidation in the reactor can proceed in the absence of Fe(III) and/or other metal compounds operable to function as an electron acceptor in the medium. Moreover, the medium may further comprise one more contaminants in addition to the ammonium component.

Systems and methods for performing bioremediation using the Geobacillus sp. bacterial strain are provided which are capable of effectively degrading Benzo[a]pyrene (BaP) and efficiently degrading other ring-based organic contaminants. The exemplary bioremediation methods include steps for administering an effective, degrading amount of the bacteria to soil containing excess amounts of BaP and incubating the bacteria administered to the soil at a given temperature and for a duration that are suitable for promoting incubation and reducing and the concentration of BaP below a maximum concentration, as might be specified by a regulatory body.

Systems and methods for performing bioremediation using the Geobacillus sp. bacterial strain are provided which are capable of effectively degrading Benzo[a]pyrene (BaP) and efficiently degrading other ring-based organic contaminants. The exemplary bioremediation methods include steps for administering an effective, degrading amount of the bacteria to soil containing excess amounts of BaP and incubating the bacteria administered to the soil at a given temperature and for a duration that are suitable for promoting incubation and reducing and the concentration of BaP below a maximum concentration, as might be specified by a regulatory body.

A biofilm process is disclosed for treating wastewater containing readily biodegradable dissolved organic matter GP (measured as chemical oxygen demand or COD) and producing surplus biomass from the biofilm process that includes an enhanced polyhydroxyalkanoate (PHA) content. The process comprises directing a wastewater influent containing the readily biodegradable COD (RBCOD) into a biofilm unit process. The PHA content of surplus biomass is enhanced by controlling for a decreased biofilm process specific organic loading rate in combination with controlling phosphorus loading rates relative to the process RBCOD loading rates: (1) controlling the wastewater influent phosphorus loading rate to the biofilm unit process includes maintaining an average RBCOD/P ratio of the influent that is between 200 and 800 g/g; (2) decreasing the process specific organic loading rate includes producing a biofilm unit process effluent having readily separable mixed liquor volatile suspended solids (RS-MLVSS); and (3) separating a portion of the RS-MLVSS from the biofilm unit process effluent and recycling at least a portion of the separated RS-MLVSS back to the biofilm unit process. The combination of the RBCOD/P control and specific loading rate control maintains, on average, the surplus biomass with a PHA content that is greater than 30% gPHA/g VSS.

The present disclosure provides an in-situ method for removing sulfates. The method comprises delivering at least one low molecular weight organic compound (LMWOC) to soil or groundwater to attain a concentration of the LMWOC of 750-3000 mg/L, such as 1000-2000 mg/L, or about 1500 mg/L, especially whereby sulfate is reduced to below 250 mg/L in the soil or groundwater. The method may further comprise contacting the soil or groundwater with an oxidizer, such as hydrogen peroxide, whereby the concentration of metals or metalloids is reduced in the soil or groundwater.

A hierarchical catalyst composition comprising a continuous or particulate macroporous scaffold in which is incorporated mesoporous aggregates of magnetic nanoparticles, wherein an enzyme is embedded in mesopores of the mesoporous aggregates of magnetic nanoparticles. Methods for synthesizing the hierarchical catalyst composition are also described. Also described are processes that use the recoverable hierarchical catalyst composition for depolymerizing lignin, remediation of water contaminated with aromatic substances, polymerizing monomers by a free-radical mechanism, epoxidation of alkenes, halogenation of phenols, inhibiting growth and function of microorganisms in a solution, and carbon dioxide conversion to methanol. Further described are methods for increasing the space time yield and/or total turnover number of a liquid-phase chemical reaction that includes magnetic particles to facilitate the chemical reaction, the method comprising subjecting the chemical reaction to a plurality of magnetic fields of selected magnetic strength, relative position in the chemical reaction, and relative motion.

Aerobic processes are disclosed for the treatment of wastewater which contains at least one substrate comprising at least one of organocarbon component and ammonium cation. A bioreactor is used for the treatment which contains ME biocatalysts to provide high bioreactor bioactivity density. The processes reduce sludge generated and are capable of effecting the metabolic oxidation at low dissolved oxygen concentrations.

The invention provides a system of heavy metal sequestration by bacteria. The bacteria expresses the ppk, mt, and/or β-galactosidase (lacZ) genes and can tolerate at least 25 μM mercury, 1,000 μM zinc, 250 μM cadmium, and 3,000 μM Pb. The system allows for facile determination of the presence of heavy metal contaminants in a liquid and the facile collection of the bacteria that has sequestered large amounts of heavy metal. Further provided is a system of gene expression in bacteria that comprises phage and plastid gene expression elements and delivers a particularly high level of protein expression and heavy metal resistance.

A process for enhanced anaerobic digestion of sludge by alcoholization of food waste, comprising steps of: (1) ethanol prefermentation of food waste—feeding the food waste having been crushed into a uniform grain size into an ethanol production reactor, where the food waste is subjected to rapid and efficient anaerobic fermentation activated by addition of yeast and pH adjustment to produce ethanol and obtain a fermentation broth and a fermentation residue; (2) sludge pretreatment—pretreating the sludge after mixing with the fermentation residue; and (3) methanogenesis of anaerobic digestion—subjecting products resulting from the sludge pretreatment to be mixed with the fermentation broth and then to methanogenesis of anaerobic digestion in a methane production reactor. With this process, the sludge and the food waste can be treated efficiently via multi-phase reactions, and the resource recovery and biogas quality can be enhanced.

A water cleaning system 1 includes an aerobic region 90 including breeding water 9 containing organic matter and oxygen, an aerobic layer 6 linking with the aerobic region 90 and inhabited by aerobic bacteria, a facultative anaerobic layer 5 provided adjacent to the aerobic layer 6 and inhabited by facultative anaerobic bacteria, an obligatory anaerobic layer 4 provided adjacent to the facultative anaerobic layer 5, inhabited by obligatory anaerobic bacteria, and made of andosol 40, an anaerobic space 3 having an anaerobic environment, allowing the obligatory anaerobic bacteria inhabiting the obligatory anaerobic layer 4 and products therefrom to flow therein, and a tube 18 as linking means linking the anaerobic space 3 and the aerobic region 90.