Entity

Time filter

Source Type


Cheng Z.-W.,Zhejiang University of Technology | Fu L.-X.,Zhejiang University of Technology | Jiang Y.-F.,Zhejiang University of Technology | Chen J.-M.,Zhejiang University of Technology | Zhang R.,Zhejiang Tianlan Environmental Protection Technology Co.
Huanjing Kexue/Environmental Science | Year: 2011

Methylibium petroleiphilum PM1, which is capable of degrading methyl tert-butyl ether (MTBE), was immobilized in calcium alginate gel beads. Several methods were explored to increase the strength of these gel beads. The central composite design analysis indicated that the introduction of 0.2 mol·L -1 Ca 2+ into the crosslinking solution, 1.38 mmol·L -1Ca 2+ into the growth medium and 0.1% polyethyleneimine (PEI) as the chemical crosslinking agent could increase the stability of the Ca-alginate gel beads with no loss of biodegradation activity. The stabilized immobilized cells could be used 400 h continuously with no breakage and no bioactivity loss. Examination of scanning electron microscope demonstrated that a membrane surrounding the gel beads was formed and the cells could grow and breed well in the stabilized calcium alginate gel beads. Kinetic analysis of the gel bead-degradation indicated that the rate-limiting step was biochemical process instead of intraparticle diffusion process. The diameter of 3 mm affected the biodegradability less while high concentration of PEI induced much more serious mass transfer restraint. Source


Lian Z.,CAS Research Center for Eco Environmental Sciences | Liu F.,CAS Research Center for Eco Environmental Sciences | He H.,CAS Research Center for Eco Environmental Sciences | Shi X.,CAS Research Center for Eco Environmental Sciences | And 2 more authors.
Chemical Engineering Journal | Year: 2014

A series of manganese-niobium mixed oxide (Mn-Nb) catalysts were prepared by homogeneous precipitation method and tested for low temperature selective catalytic reduction of NOx with NH3 (NH3-SCR). These catalysts were characterized by N2 adsorption, X-ray diffraction, H2-TPR, X-ray photoelectron spectroscopy, NOx-TPD and NH3-TPD. Among the series of Mn-Nb catalysts, Mn2Nb1Ox calcined at 500°C exhibited the best catalytic activity. MnOx had stronger redox capability than Mn2Nb1Ox, resulting in lower N2 selectivity due to the unselective oxidation of NH3 at relatively high temperatures. The addition of Nb to MnOx enhanced the acidity, especially the Brønsted acidity, which is responsible for the low temperature SCR activity. The combination of MnOx with strong redox capability and NbOx with high acidity simultaneously led to high NOx conversion and N2 selectivity over the Mn2Nb1Ox catalyst. © 2014. Source


Liu X.,Zhejiang Tianlan Environmental Protection Technology Co. | Sheng H.,Zhejiang Tianlan Environmental Protection Technology Co. | Cheng C.,Zhejiang Tianlan Environmental Protection Technology Co. | Mo J.,Zhejiang Tianlan Environmental Protection Technology Co.
Chinese Journal of Environmental Engineering | Year: 2013

White mud contains a lot of impurities, such as sodium, magnesium, chlorine ion and the black jelly, which would influence the adsorption of SO2 during the desulfurization process. Therefore, in this work the effect of different impurities was studied. Results showed that the mass transfer reactions would be promoted by the sodium sulfate and high concentrations of magnesium sulfate, while hindered by the chlorine ion, black jelly, and low concentrations of magnesium sulfate. Meanwhile, the influence of impurity concentrations on the mass transfer reactions was also studied. The K/β-c of low concentrations of magnesium sulfate is in line with the form of Gaussian function. Source


Liu X.,Zhejiang Tianlan Environmental Protection Technology Co. | Mo J.,Zhejiang Tianlan Environmental Protection Technology Co. | Cheng C.,Zhejiang Tianlan Environmental Protection Technology Co. | Zhai C.,Zhejiang Tianlan Environmental Protection Technology Co. | Yang Y.,Zhejiang Tianlan Environmental Protection Technology Co.
Chinese Journal of Environmental Engineering | Year: 2013

Considering the properties of desulfurized ash and desulfurization gypsum, suspended separation of impurities in the desulfurized gypsum was studied in an unbaffled, fat bottom, cylindrical stirred tank. Results found that low ratio of suspension height was favorable for the separation of impurities during the off-bottom suspension stirring. For the stirred tank with a diameter above 24 cm, the separation efficiency of impurities (η) reached a highest value of about 82% when the off-bottom height of blades (cb) and the diameter ratio of blades to tank (d/D) were 4 cm and 0.65, respectively. For the stirred tank with a diameter of 20 cm, the η increased with the d/D. And the influence of d/D on η could be alleviated by the reduction of the off-bottom span of blades. When cb was 4 cm, the η increased with the diameter of the agitation tank, and it varied dramatically with the lowering of cb. After the off-bottom suspension separation, the purity of gypsum was improved. Source


Zhang R.,Zhejiang Tianlan Environmental Protection Technology Co. | Xia C.,Zhejiang Tianlan Environmental Protection Technology Co. | Ni H.,Zhejiang Tianlan Environmental Protection Technology Co. | Zhai C.,Zhejiang Tianlan Environmental Protection Technology Co. | And 2 more authors.
Chinese Journal of Environmental Engineering | Year: 2014

It is very important to study the influences of impurities in desulfurized ash on limestone desulfurization reactivity. Using the Metrohm 902 titrando, the influences of impurities in desulfurized ash on limestone desulfurization reactivity were studied by the measurement of dissolution rate of limestone powder. The results showed that in the range of concentration of experiments, the limestone reactivity would be improved by SiO2, Al2O3, CaSO3, while, would be inhibited by MgO, Fe2O3 in a certain range. When the desulfurizer is blend of desulfurized ash and limestone power, it is very important to select the appropriate desulfurized ash blend ratio, based on the influences of these five impurities in desulfurized ash on limestone desulfurization reactivity. ©, 2014, Science Press. All right reserved. Source

Discover hidden collaborations