The process of using flat-sheet membrane for simultaneous sludge thickening and digestion （MSTD） was employed. The variations of sludge concentration and rheology were characterized and simulated. Based on mass bala...The process of using flat-sheet membrane for simultaneous sludge thickening and digestion （MSTD） was employed. The variations of sludge concentration and rheology were characterized and simulated. Based on mass balance analysis, mathematical models were developed and successfully used to predict and evaluate the variations of sludge concentration and the digestion efficiency in the MSTD process. The apparent viscosity of sludge could be modeled as functions of mixed liquor suspended solids and shear rates. The sludge in the MSTD process showed both shear-thinning and viscoplastic behaviour, and under various shear rates different rheological models could be chosen to predict their flow behaviour. It was also found that sludge concentration and viscosity had significant correlations with membrane fouling in the MSTD process.展开更多
Both bottle-point and column-feeding experi-ments involving different solutes and sorbents were carried out to investigate the adsorption selectivity and separation performance of salicylic acid and 5-sulfosalicylic a...Both bottle-point and column-feeding experi-ments involving different solutes and sorbents were carried out to investigate the adsorption selectivity and separation performance of salicylic acid and 5-sulfosalicylic acid.Their adsorption isotherms onto such hypercrosslinked polymeric adsorbents as NDA-100 and NDA-99 could be well described by the Freundlich equations whose characteristics describe extrathermic and favorable adsorption processes.The adsorp-tion towards NDA-100 mainly depended on the p-p interac-tion,while that towards NDA-99 was extremely influenced by the static-electric interaction.Additionally,the adsorptive capacity of salicylic acid on NDA-99 decreased while it increased on NDA-100 with the presence of 5-sulfosalicylic acid in the adsorptive environment as the competitive component.Comparatively,the adsorption capacity of 5-sulfosalicylic acid decreased on both resins with salicylic acid as the competitive component.In fact,the difference in the interaction between adsorbent and adsorbate resulted in the straight antagonism on the effective adsorption sites on the adsorbent.In conclusion,the adsorption selectivity of salicylic acid onto NDA-100 was obviously larger than that onto NDA-99 with the existence of 5-sulfosalicylic acid in the adsorptive environment.A satisfactory separation and recovery of tested solutes in aqueous phase could be foresee-ably achieved by the sequencing adsorption technique involving NDA-100 as well as NDA-99.展开更多
基金supported by the Foundation of Chinese State Key Laboratory of Pollution Control and Resource Reuse for Young Scholars (No. PCRRY08005)by the Science and Technology Commission of Shanghai Municipality (No. 08231200200)
文摘The process of using flat-sheet membrane for simultaneous sludge thickening and digestion （MSTD） was employed. The variations of sludge concentration and rheology were characterized and simulated. Based on mass balance analysis, mathematical models were developed and successfully used to predict and evaluate the variations of sludge concentration and the digestion efficiency in the MSTD process. The apparent viscosity of sludge could be modeled as functions of mixed liquor suspended solids and shear rates. The sludge in the MSTD process showed both shear-thinning and viscoplastic behaviour, and under various shear rates different rheological models could be chosen to predict their flow behaviour. It was also found that sludge concentration and viscosity had significant correlations with membrane fouling in the MSTD process.
基金The work was supported by the Opening Fund of Key Laboratory of Environmental Engineering of Jiangsu Province,China(Grant No.KF0502)by the Opening Fund of Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection(Grant No.JLCBE05005).
文摘Both bottle-point and column-feeding experi-ments involving different solutes and sorbents were carried out to investigate the adsorption selectivity and separation performance of salicylic acid and 5-sulfosalicylic acid.Their adsorption isotherms onto such hypercrosslinked polymeric adsorbents as NDA-100 and NDA-99 could be well described by the Freundlich equations whose characteristics describe extrathermic and favorable adsorption processes.The adsorp-tion towards NDA-100 mainly depended on the p-p interac-tion,while that towards NDA-99 was extremely influenced by the static-electric interaction.Additionally,the adsorptive capacity of salicylic acid on NDA-99 decreased while it increased on NDA-100 with the presence of 5-sulfosalicylic acid in the adsorptive environment as the competitive component.Comparatively,the adsorption capacity of 5-sulfosalicylic acid decreased on both resins with salicylic acid as the competitive component.In fact,the difference in the interaction between adsorbent and adsorbate resulted in the straight antagonism on the effective adsorption sites on the adsorbent.In conclusion,the adsorption selectivity of salicylic acid onto NDA-100 was obviously larger than that onto NDA-99 with the existence of 5-sulfosalicylic acid in the adsorptive environment.A satisfactory separation and recovery of tested solutes in aqueous phase could be foresee-ably achieved by the sequencing adsorption technique involving NDA-100 as well as NDA-99.
