The removal of four dissolved organic matter(DOM) fractions, non-acid hydrophobics,hydrophobic acids, hydrophilics and transphilics, was achieved by coagulation-UV/H_2O_2 oxidation in post-pharmaceutical wastewater(Ph...The removal of four dissolved organic matter(DOM) fractions, non-acid hydrophobics,hydrophobic acids, hydrophilics and transphilics, was achieved by coagulation-UV/H_2O_2 oxidation in post-pharmaceutical wastewater(PhW W). Coagulation with Polyferric chloride(PFC), Polymeric ferric sulfate(PFS) and Polymeric aluminum ferric chloride(PAFC) was studied separately to evaluate the effects of the initial pH and coagulant dosage. The coagulation-UV/H_2O_2 oxidation method resulted in much higher reduction rates for dissolved organic carbon(DOC)(by 75%) and UV_(254)(by 92%) than coagulation or UV/H_2O_2 oxidation alone. The proportion of non-acid hydrophobics, hydrophobic acids, transphilics and hydrophilics removed by coagulation was 54%, 49%, 27% and 12 %, while the combined treatment removed 92%, 87%,70% and 39%, respectively. Parallel factor analysis(PARAFAC) of fluorescence measurements revealed that the humic-like fluorescent component C4 showed the highest removal(by 44%)during the coagulation stage. After coagulation-UV/H_2O_2 treatment, the humic-like fluorescent component C3 had the highest removal(by 72%), whereas xenobiotic organic fluorescent components C1 and C4 remained recalcitrant to decomposition. Significant correlations(R2> 0.8)between C1 and the hydrophobic acids and non-acid hydrophobics suggested the possibility of using fluorescence spectroscopy as an effective tool to assess variations in DOM fraction treatment efficacy in coagulation-UV/H_2O_2 systems. After the combined treatment, toxic inhibition of cellular activity by post PhW W decreased from 88% to 47% and biodegradability increased from 0.1 to 0.52.展开更多
Hydrothermal liquefaction(HTL)has been studied as a promising technology for converting wet biomass into bio-crude oil and the nutrient-rich post-hydrothermal liquefaction wastewater(PHWW)could be reused for algae and...Hydrothermal liquefaction(HTL)has been studied as a promising technology for converting wet biomass into bio-crude oil and the nutrient-rich post-hydrothermal liquefaction wastewater(PHWW)could be reused for algae and bacteria production.However,the PHWW from HTL contains various types of contaminants that need to be removed before reuse.Too high nutrients(nitrogen and phosphorous)contents,such as ammonium,are inhibitive to algal growth and bacteria species in anaerobic process.It is desirable to reduce nutrients concentration in PHWW to an acceptable level using zeolite adsorption.This study investigated nitrogen and phosphorous adsorption efficiencies from PHWW using three types of zeolites:activated clinoptilolite,natural clinoptilolite and Na-modified zeolite.Effects of ions and pH in the adsorption process were also investigated.Results showed that three zeolite variables affecting ammonium adsorption process could be ranked as follows:zeolite dosage>type>particle size,via an orthogonal experiment design.Activated clinoptilolite,with a particle size of 0.18-0.30 mm and a dosage of 0.4 g/mL demonstrated the highest ammonium adsorption efficiency of 54.92%.Zeolite could also adsorb organic nitrogen and had a high adsorption efficiency of phosphorous(97.85%).This study showed that zeolite is effective to adsorb nutrients in PHWW.The adsorption treated PHWW can then be used for culturing algae or anaerobic treatment,and the adsorbed nutrients can be reused later.展开更多
基金supported by the National Key Scientific and Technological Project for Water Pollution Control and Management (Nos.2012ZX07202-005,2012ZX07202-002,2014 ZX07216001-2)
文摘The removal of four dissolved organic matter(DOM) fractions, non-acid hydrophobics,hydrophobic acids, hydrophilics and transphilics, was achieved by coagulation-UV/H_2O_2 oxidation in post-pharmaceutical wastewater(PhW W). Coagulation with Polyferric chloride(PFC), Polymeric ferric sulfate(PFS) and Polymeric aluminum ferric chloride(PAFC) was studied separately to evaluate the effects of the initial pH and coagulant dosage. The coagulation-UV/H_2O_2 oxidation method resulted in much higher reduction rates for dissolved organic carbon(DOC)(by 75%) and UV_(254)(by 92%) than coagulation or UV/H_2O_2 oxidation alone. The proportion of non-acid hydrophobics, hydrophobic acids, transphilics and hydrophilics removed by coagulation was 54%, 49%, 27% and 12 %, while the combined treatment removed 92%, 87%,70% and 39%, respectively. Parallel factor analysis(PARAFAC) of fluorescence measurements revealed that the humic-like fluorescent component C4 showed the highest removal(by 44%)during the coagulation stage. After coagulation-UV/H_2O_2 treatment, the humic-like fluorescent component C3 had the highest removal(by 72%), whereas xenobiotic organic fluorescent components C1 and C4 remained recalcitrant to decomposition. Significant correlations(R2> 0.8)between C1 and the hydrophobic acids and non-acid hydrophobics suggested the possibility of using fluorescence spectroscopy as an effective tool to assess variations in DOM fraction treatment efficacy in coagulation-UV/H_2O_2 systems. After the combined treatment, toxic inhibition of cellular activity by post PhW W decreased from 88% to 47% and biodegradability increased from 0.1 to 0.52.
基金This work is supported by Doctoral Programs Foundation of Ministry of Education of China(20130008120004)Chinese Universities Scientific Fund(2015SYL004)National Natural Science Foundation of China(51576206).
文摘Hydrothermal liquefaction(HTL)has been studied as a promising technology for converting wet biomass into bio-crude oil and the nutrient-rich post-hydrothermal liquefaction wastewater(PHWW)could be reused for algae and bacteria production.However,the PHWW from HTL contains various types of contaminants that need to be removed before reuse.Too high nutrients(nitrogen and phosphorous)contents,such as ammonium,are inhibitive to algal growth and bacteria species in anaerobic process.It is desirable to reduce nutrients concentration in PHWW to an acceptable level using zeolite adsorption.This study investigated nitrogen and phosphorous adsorption efficiencies from PHWW using three types of zeolites:activated clinoptilolite,natural clinoptilolite and Na-modified zeolite.Effects of ions and pH in the adsorption process were also investigated.Results showed that three zeolite variables affecting ammonium adsorption process could be ranked as follows:zeolite dosage>type>particle size,via an orthogonal experiment design.Activated clinoptilolite,with a particle size of 0.18-0.30 mm and a dosage of 0.4 g/mL demonstrated the highest ammonium adsorption efficiency of 54.92%.Zeolite could also adsorb organic nitrogen and had a high adsorption efficiency of phosphorous(97.85%).This study showed that zeolite is effective to adsorb nutrients in PHWW.The adsorption treated PHWW can then be used for culturing algae or anaerobic treatment,and the adsorbed nutrients can be reused later.
