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Bacterial communities, taxonomic functional groups, and chemical characteristics of granular sludge were assessed in an ultrahigh-temperature (70°C) upflow anaerobic sludge blanket reactor (UASB) used to treat super heavy oil-containing wastewater. The UASB, with an organic loading rate of 3.0 kg COD m−3 day−1, achieved an average chemical oxygen demand removal of 48%, with 52% oil removal from the wastewater. It was also found to successfully degrade two typical biomarkers of super heavy oil, C26-34 17α 25-norhopanes and C26-28 triaromatic steroid. Scanning electron microscope, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction results showed that the granular sludge became more compact with an increased quantity of extracellular polymeric substances, Fe2O3, FeS, and CaCO3 crystals in the reactor. Polymerase chain reaction-denaturing gradient gel electrophoresis and real-time polymerase chain reaction results indicated that after 90 days of operation, the density of total bacteria in the UASB dropped while Pseudomonas density increased, making it a dominant bacterium in the reactor. Data obtained from this research will provide useful information and insights with respect to effective treatment for super heavy oil wastewater under ultrahigh-temperature conditions. [ABSTRACT FROM AUTHOR]

Ceramsite materials made from coal ash and modifiers such as sawdust, clinoptilolite, clay, and CaCO3 were prepared by pelletizing and high-temperature sintering to improve the adsorption to nitrogen and phosphorus. To incorporate Fe/C and Fe/Fe3C microelectrochemical cells, materials were also modified by the addition of metallic iron during the preparation process. Addition of more iron increased the Brunauer, Emmett, and Teller surface area and average pore diameter while decreasing the packing density and acid and alkali solubility. Examination using X-ray diffraction and X-ray fluorescence revealed that metallic iron modification also increased the abundance of Fe3C and FeC8 particles and electrochemical effects. Time required to reach adsorption equilibrium decreased with addition of iron. Ammonia nitrogen and phosphorus adsorption isotherms and kinetics for each ceramsite composition followed the Langmuir isotherm model in a similar second-order manner with respect to the amount of iron. Results provide useful information for preparing ceramsites with enhanced nitrogen and phosphorus adsorption capacity and thus improved biofilter efficiency. [ABSTRACT FROM AUTHOR]