Although many efforts have been devoted to the adsorptive removal of phosphate from aqueous solutions and eutrophic water, it is still highly desirable to develop novel adsorbents with high adsorption capacities. In this study, Fe-based metal-organic frameworks (MOFs), MIL-101 and NH2-MIL-101, are fabricated through a general facile strategy. Their performance as an adsorbent for phosphate removal is investigated. Experiments are performed to study the effects of various factors on the phosphate adsorption, including adsorbent dosage, contact time and co-existing ions. Both MIL-101(Fe) and NH2-MIL-101(Fe) show highly effective removal of phosphates from aqueous solutions, and the concentration of phosphates decrease sharply from the initial 0.60 mg·L−1 to 0.045 and 0.032 mg·L−1, respectively, within just 30 min of exposure. The adsorption kinetics and adsorption isotherms reveal that NH2-MIL-101(Fe) has higher adsorption capacity than MIL-101(Fe) possibly due to the amine group. Furthermore, the Fe-based MOFs also exhibit a high selectivity towards phosphate over other anions such as chloride, bromide, nitrate and sulfate. Particularly, the prepared Fe-based MIL-101 materials are also capable of adsorbing phosphate in an actual eutrophic water sample and display better removal effect.

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The concept of high-temperature air/steam-blown gasification technology for converting coal into lowcaloric-value gas for power generation is proposed and evaluated experimentally. Preliminary experiments are performed in a 0.1 MW thermal input pressurized spout-fluid bed gasifier. The influences of the gasifying agent preheat temperature, the gasification temperature and pressure, the equivalence ratio, the ratio of steamto-coal on gas composition, gas higher heating value, carbon conversion, and cold gas efficiency are examined. The experimental results prove the feasibility of high-temperature air/steam-blown gasification process. The gas heating value is increased by 23%, when the gasifying agent temperature is increased from 300 to 700 °C. For the operation conditions studied, the results show that gasification temperature is the most important factor influencing coal gasification in the spout-fluid bed. The gasifier performance is improved at elevated pressure mainly due to the better fluidization in the reactor. The operating parameters of the equivalence ratio and the ratio of steam-to-coal exist at optimum operating range for a certain coal gasification process.

The formation of sulfur trioxide (SO(3)) in coal-fired utility boilers can have negative effects on boiler performance and operation, such as fouling and corrosion of equipment, efficiency loss in the air preheater (APH), increase in stack opacity, and the formation of PM(2.5). Sulfur trioxide can also compete with mercury when bonding with injected activated carbons. Tests in a lab-scale reactor confirmed there are major interferences between fly ash and SO(3) during SO(3) sampling. A modified SO(3) procedure to maximize the elimination of measurement biases, based on the inertial-filter-sampling and the selective-condensation-collecting of SO(3), was applied in SO(3) tests in three full-scale utility boilers. For the two units burning bituminous coal, SO(3) levels starting at 20 to 25 ppmv at the inlet to the selective catalytic reduction (SCR), increased slightly across the SCR, owing to catalytic conversion of SO(2) to SO(3,) and then declined in other air pollutant control device (APCD) modules downstream to approximately 5 ppmv and 15 ppmv at the two sites, respectively. In the unit burning sub-bituminous coal, the much lower initial concentration of SO(3) estimated to be approximately 1.5 ppmv at the inlet to the SCR was reduced to about 0.8 ppmv across the SCR and to about 0.3 ppmv at the exit of the wet flue gas desulfurization (WFGD). The SO(3) removal efficiency across the WFGD scrubbers at the three sites was generally 35% or less. Reductions in SO(3) across either the APH or the dry electrostatic precipitator (ESP) in units burning high-sulfur bituminous coal were attributed to operating temperatures being below the dew point of SO(3).