Yi Qian

Tsinghua University, Peping, Beijing, China

Are you Yi Qian?

Claim your profile

Publications (110)183.95 Total impact

  • Bing Yu · Xiao Li · Lei Shi · Yi Qian
    [Show abstract] [Hide abstract]
    ABSTRACT: The low-carbon transition of iron and steel industry is vital for meeting China's CO2 emission reduction targets. Industrial symbiosis provides important opportunities for CO2 abatement in China's integrated steel mills (ISMs). A set of methodological rules were proposed for quantification of CO2 abatement from industrial symbiosis. We defined both cleaner production inside an ISM and synergistic measures with other enterprises as symbiotic measures, and classified them into three groups. Three methods were proposed for quantifying CO2 emission reduction under different data conditions. A case was designed on the basis of a typical ISM in China. The calculation results of our case showed that: 1) the three most effective symbiotic measures for CO2 abatement were blast furnace gas (BFG) recycled on site as fuel and sold off site, coke oven gas (COG) recycled on site as fuel and sold off site, and blast furnace (BF) slag sold to cement industry; 2) at present utilizations of gaseous and solid waste/byproducts far outweighed the use of sensible heat in terms of their contributions to CO2 abatement, which also indicated the abundant potentials in sensible heat recovery; 3) cleaner production inside an ISM contributed more to CO2 abatement than symbiotic measures with other enterprises did, which proved the arguments of other studies. The calculation and analyses of the case tested the applicability of our definition and methodological rules, and provided a reference result for related research. Finally, suggestions were provided for improving the contribution of industrial symbiosis to CO2 abatement in ISMs in China.
    Journal of Cleaner Production 08/2014; 103. DOI:10.1016/j.jclepro.2014.08.015 · 3.84 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A continuous-flow three-dimensional electrode reactor (CTDER) was constructed. COD from the citric acid wastewater was effectively removed in CTDER. The COD removal rate in CTDER was 1.7 times that of the continuous 2D reactor. Aeration in the CTDER had a negative effect on COD removal. Organics from wastewater were degraded primarily via indirect oxidation reaction. a b s t r a c t In this study, we constructed a continuous-flow three-dimensional electrode reactor (CTDER) to remove organic compounds from biologically-treated citric acid wastewater. We analyzed the effects of the residence time, current density, initial pH, and airflow rate on the reactor's energy consumption (E s), general current efficiency (GCE), and ability to remove the chemical oxygen demand (COD). We determined that the optimal operation conditions for the reactor included a residence time of 5 min, a current density of 40 mA cm À2 , and an initial pH of 5. Under these conditions, we determined that 55.7% of COD was removed. The resulting COD of the effluent was within the National Discharge Standard of China (COD < 100 mg L À1), and the E s and GCE were 274.8 kW h kg COD À1 and 16.2%, respectively. We also found that aeration in the CTDER negatively affected COD removal due to the short-circuiting of the fluid. Further investigation revealed that the CTDER could produce a steady effluent quality where the organic compounds were degraded primarily via the indirect electrochemical oxidation of humic acid-like substances in the citric acid wastewater. Our results demonstrate that the CTDER is a highly efficient system for the electrochemical treatment of biologically-treated citric acid wastewater.
    Chemical Engineering Journal 09/2013; 232. DOI:10.1016/j.cej.2013.08.007 · 4.32 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this study, we investigated the use of an electrochemical oxidation process to simultaneously remove chemical oxygen demand (COD), turbidity, and hardness from biologically treated citric acid wastewater that was non-biodegradable and contained high concentrations of inorganic salts. We employed a Ti/RuO2–IrO2 anode system to analyse the effects of electric voltage and initial chloride concentration on COD, turbidity, and hardness removal as well as on energy consumption. Under optimal conditions (electric voltage of 9 V, initial chloride concentration of 3000 mg L−1), organic pollutants were almost completely mineralised after 60 min of electrolysis. The resulting COD (6 mg L−1) and turbidity (3 NTU) of effluent was within the Water Reuse Standard of China (COD < 30 mg L−1, turbidity < 5 NTU) while energy consumption (Es) and general current efficiency (GCE) were 99 kW h kg COD−1 and 30%, respectively. We also found that electric voltage and initial chloride concentrations increased the rate of hardness removal. Further investigation revealed that organics were mainly degraded by electrochemical oxidation of humic and fulvic acid-like substances, and hardness was primarily removed via the production of CaMg(CO3)2 precipitate on the cathode surface.
    Separation and Purification Technology 04/2013; 107:281-288. DOI:10.1016/j.seppur.2013.01.008 · 3.07 Impact Factor
  • Source
  • Source
    Xianghua Wen · Xia Huang · Yi Qian
    [Show abstract] [Hide abstract]
    ABSTRACT: China has been experiencing fast economic development in recent decades at the cost of serious environmental deterioration. Wastewater discharge, especially municipal wastewater discharge, and non-point pollution sources are becoming the major water pollution source and research focus. Great efforts have been made on water pollution control and a number of renovated technologies and processes for municipal wastewater treatment and reclamation as well as non-point pollution control have been developed and applied in China. This paper discusses the development and application of the appropriate technologies, including natural treatment systems, anaerobic biological treatment, biofilm reactors and wastewater reclamation technologies, for water pollution control in the country.
  • [Show abstract] [Hide abstract]
    ABSTRACT: The simultaneous removal of K and P from urine for nutrient recycling by crystallization of magnesium potassium phosphate hexahydrate (MPP) in a laboratory-scale draft tube and baffle reactor (DTBR) is investigated. Results show that mixing speed and hydraulic retention time are important operating factors that influence crystallization and crystal settlement. Slurry should be discharged at a crystal retention time of 11 h to maintain fluidity in the reactor. Further applications of the DTBR using real urine (pretreated by ammonia stripping and diluted five times) showed that 76% K and 68% P were recycled to multi-nutrient products. The crystals collected were characterized and confirmed mainly as a mixture of magnesium ammonium phosphate hexahydrate, MPP, and magnesium sodium phosphate heptahydrate. Results indicate that the DTBR effectively achieved the simultaneous recycling of K and P from urine to multi-nutrient products through MPP crystallization.
    Chemosphere 03/2012; 88(2):219-23. DOI:10.1016/j.chemosphere.2012.02.061 · 3.50 Impact Factor
  • Source
    Yi Qian
    02/2012; 6(1). DOI:10.1007/s11783-012-0398-7
  • [Show abstract] [Hide abstract]
    ABSTRACT: This study investigated the simultaneous removal of P and K from synthetic urine through the precipitation of magnesium potassium phosphate hexahydrate (MPP, MgKPO(4)·6H(2)O) in bench-scale experiments. Results show that the removal efficiencies of P and K are mainly determined by the solution pH and the molar ratio of Mg:K:P. Co-precipitation of struvite-type compounds, i.e., magnesium ammonium phosphate hexahydrate (MAP, MgNH(4)PO(4)·6H(2)O), magnesium sodium phosphate heptahydrate (MSP, MgNaPO(4)·7H(2)O), and MPP, was confirmed by analysis of the solid precipitates using a Scanning Electron Microscope/Energy Dispersive X-ray Apparatus and an X-ray Diffractometer. The co-precipitation significantly influenced the removal of K. As much ammonium as possible should be removed prior to MPP precipitation because MAP had higher tendency to form than MPP. The inevitable co-precipitation of MPP and MSP resulted in the addition of more MgCl(2)·6H(2)O and Na(2)HPO(4)·12H(2)O to obtain the high removal of K. In total, the removal efficiencies of P and K were 77% and 98%, respectively, in the absence of ammonium when pH was 10 and the molar ratio of Mg:K:P was 2:1:2. The results indicate that the MPP precipitation is an efficient method for the simultaneous removal of P and K to yield multi-nutrient products.
    Chemosphere 06/2011; 84(2):207-12. DOI:10.1016/j.chemosphere.2011.04.057 · 3.50 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The dechlorination of pentachlorophenol (PCP) using nano-Fe together with different size of nano-Ni particles (30, 50, 80, and 100nm) was investigated. The results indicated that nano-Ni particles could improve the dechlorination of PCP. The X-ray powder diffraction (XRD) analysis suggested that nano-Ni particles might serve as catalyst for dechlorination. The decrease of nano-Ni particle size resulted in the increase of PCP transformation and chloride release. The accumulation of several intermediates, such as phenol, 2-chlorophenol, 3-chlorophenol and 4-chlorophenol indicated the probable changes of the reaction pathway for PCP dechlorination. The corrosion products of Fe were detected using XRD analysis. In the system without nano-Ni particles, they were lepidocrocite (gamma-FeOOH) and magnetite (Fe(3)O(4)) and/or maghemite (Fe(2)O(3)), however, in the systems with nano-Ni particles, they were still magnetite/maghemite but no lepidocrocite existed. The size of nano-Ni particles might affect the crystallization of corrosion products of Fe, but did not affect the species distribution of corrosion products.
    Journal of hazardous materials 08/2010; 180(1-3):79-85. DOI:10.1016/j.jhazmat.2010.03.068 · 4.33 Impact Factor
  • Weiqiang Chen · Lei Shi · Yi Qian
    [Show abstract] [Hide abstract]
    ABSTRACT: Based on the characterization of aluminium life cycle in the anthroposphere, stocks and flows accounting of aluminium in mainland China for 2001, 2004 and 2007 was performed in this paper. Findings include the following: (1) the production and consumption of aluminium contained in aluminium-containing products generated from each life process grew from 2001 to 2004, and then to 2007; (2) the share of recycled aluminium in both production and consumption of unwrought aluminium was in the range of 20–26%, and a majority of aluminium scrap used to produce recycled aluminium for 2004 and 2007 came from net import, which revealed that China was still in the stage of mainly depending on primary aluminium rather than secondary aluminium and the in-use stock of aluminium was still too small to generate enough end-of-life (EOL) scrap; (3) China was a net importer of aluminium from the life cycle perspective, with total net import increasing from 2001 to 2004, and then to 2007; as for the trade structure, China was a net importer of raw materials including bauxite, alumina, EOL products and aluminium scrap, while a net exporter of unwrought aluminium and final products, and changed from a net importer of wrought products in 2001 and 2004 to a net exporter in 2007; (4) total quantity losses of aluminium in China increased from 2001 to 2004 and then to 2007 as a result of the growth of production; (5) depletion of domestic ore stock in China also increased from 2001 to 2004, and then to 2007, making China's depletion time of bauxite probably less than 15 years; (6) growth of in-use stock was 2.4kg per capita, 3.7kg per capita and 6.3kg per capita for 2001, 2004 and 2007, respectively; (7) more than 80% of the addition of aluminium to the deposited stock came from aluminium losses in Bauxite Mining and Alumina Refining processes.
    Resources Conservation and Recycling 07/2010; 54(9):557-570. DOI:10.1016/j.resconrec.2009.10.013 · 2.69 Impact Factor
  • Source
    Yi Qian
    Frontiers of Environmental Science & Engineering in China 03/2010; 4(1). DOI:10.1007/s11783-010-1000-9 · 0.75 Impact Factor
  • Source
    Yi Qian
    Frontiers of Environmental Science & Engineering in China 02/2009; 3(1):1-1. DOI:10.1007/s11783-009-0002-y · 0.75 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: White rot fungi is capable of oxidizing many persistent organic pollutants including dyes. The application of the fungi has been limited for wastewater treatment under non-sterile conditions due to the contamination by bacteria and other micro-organisms. We developed a treatment approach by using immobilized white rot fungi Phanerochaete chrysosporium to degrade reactive dye K-2BP under non-sterile condition. Four different inert carriers were tested for immobilization of the white rot fungi with orthogonal experiments in comparison with suspension culture. The activity of manganese peroxidase (MnP) was used for the evaluation of oxidization performance in order to understand whether contamination of bacteria and other micro-organisms was suppressed. Under non-sterile conditions, the immobilized fungal cultures successfully restrained the growth of microzymes, coccies, and bacillus but suspension culture was highly contaminated with poor MnP activity. Under non-sterile conditions, higher MnP enzymatic activity (690U/L vs. 125U/L), higher decolorization efficiency (93.5% vs. 15%) and shorter reaction period (3 days vs. 6 days) were achieved in immobilized cultures in comparison with suspension culture. With the immobilized fungal cultures, no difference was observed under non-sterile and sterile conditions for the degradation of reactive dye K-2BP.
    PROCESS BIOCHEMISTRY 09/2008; 43(9):937-944. DOI:10.1016/j.procbio.2008.04.026 · 2.52 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The production of ligninolytic enzymes and protease by Phanerochaete chrysosporium was investigated under different culture conditions. Different amounts of medium were employed in free and immobilized culture, together with two kinds of medium with different C/N ratios. Little lignin peroxidase (LiP) (< 2 U/L) was detected in free culture with nitrogen-limited medium (C/N ratio: 56/2.2, in mmol/L), while manganese peroxidase (MnP) maximum activity was 231 and 240 U/L in 50 and 100 ml medium culture, respectively. Immobilized culture with 50 ml nitrogen-limited medium gave the highest MnP and LiP production with the maximum values of 410 and 721 U/L separately on the day 5; however, flasks containing 100 ml nitrogen-limited medium only produced less MnP with a peak value of 290 U/L. Comparatively, carbon-limited medium (C/N ratio: 28/44, in mmol/L) was adopted in culture but produced little MnP and LiP. Medium type had the greatest impact on protease production. Large amount of protease was produced due to glucose limitation. Culture type and medium volume influence protease activity corporately by affecting oxygen supply. The results implied shallow immobilized culture was a possible way to gain high production of ligninolytic enzymes.
    Journal of Environmental Sciences 02/2008; 20(1):94-100. DOI:10.1016/S1001-0742(08)60014-5 · 1.92 Impact Factor
  • Source
    DaWen Gao · XiangHua Wen · Yi Qian
    [Show abstract] [Hide abstract]
    ABSTRACT: In order to explore ways for the application of white rot fungus in dye effluent treatment under non-sterile conditions, experiment on decolorization of reactive brilliant red was carried out, employing nitrogen-limited and carbon-limited medium with C/N ratio of 56/2.2 and 28/44 (in mmol/L), respectively. The results showed that the decolorization rate reached 92% while culturing white rot fungus with nitrogen-limited medium; however, the decolorization process ended in carbon-limited medium (n(C)/n(N) = 28/44) because of bacterial contamination. In addition, pH rose up to 9.31 after 4 d of decolorization, which was caused by bacterial contamination in the carbon-limited system. Therefore, it is concluded that nitrogen-limited medium can inhibit bacterial growth to some extent while carbon-limited medium is more easily contaminated by bacteria. Nitrogen-limited medium is more suitable in culture of white rot fungus for decolorization of reactive dye. Medium with the ability of inhibiting yeast growth should be developed by adjusting other components of nitrogen-limited medium.
    Science in China Series B Chemistry 09/2007; 50(5):718-724. DOI:10.1007/s11426-007-0108-7 · 1.20 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Microcystins (MCs) are a group of closely related toxic cyclic heptapeptides produced by common cyanobacteria, which cause lots of accidents and threatens human health. In this paper, an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) was established and used to detect microcystin-LR (MC-LR) in drinking and surface waters. The concentration of coating antigen was 5 μ/mL, the dilution of monoclonal antibody MC10E7 was 1:3 000, the dilution of enzyme tracer (goat anti-mouse IgG-peroxidase) was 1:3 000, the standard concentration of MC-LR ranged from 0.001 μg/L to 30 μg/L, and o-phenylenediamine was used as substrate. The assay showed high relativity with high performance liquid chromatography (HPLC) with a correlation coefficient of more than 99%. The relative standard deviation was less than 10%, the detection limit was achieved down to 0.01 μg/L and up to 5.1 μg/L. The quantitative detection range was from 0.03 μg/L to 3 μg/L, and the antibody had high specificity for [4-arginine] microcystins. It performed well in spite of the influence of the real samples.
    Frontiers of Environmental Science & Engineering in China 07/2007; 1(3):329-333. DOI:10.1007/s11783-007-0056-7 · 0.75 Impact Factor
  • Source
    Xia Huang · Yaobin Meng · Peng Liang · Yi Qian
    [Show abstract] [Hide abstract]
    ABSTRACT: Membrane separation was employed in a novel photocatalytic oxidation slurry reactor to conserve catalyst. This paper reports some critical operational conditions of this reactor. While fine-bubble aeration served to suspend the catalyst, introducing an intermittent coarse bubbling under the membrane during operation was vital to counteract TiO2 catalyst entrapment on membrane surface. Circulation flow in the reactor was also found to have certain effect on counteracting the dropping out of catalyst. A submerged membrane module with a pore size of 0.1μm successfully conserved the powdered catalysts within the reactor after 2 days’ preluding filtration. As for pollutant removal, membrane filtration and circulation flow had no effect, whereas increase in gas holdup had. Running the reactor to treat model pollutant dissolved in tap water revealed that calcium carbonate both deactivated the catalyst and contributed to membrane fouling, suggesting that water hardness and alkalinity deserves appropriate treatment to warrant a good performance of such a reactor.
    Separation and Purification Technology 06/2007; 55(2):165-172. DOI:10.1016/j.seppur.2006.11.018 · 3.07 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Biomass control techniques are very important for biofilters treating volatile organic compounds (VOCs) to enhance their long-term operation performance. In this study, four paralleled biofilters were set up treating toluene gas. The chemical removal of excess biomass and its impact on biofilter operation were investigated. The experimental results of circulating wash showed that the optimal washing time for biomass removal was 2 - 3 hours by NaOH ranging from 0.2% to 0.8%. Among the four experimental concentrations, the NaOH solution of 0.4% was more effective to remove the biomass from the biofilter and biomass shearing was the main process of the biomass removal under this circumstance. According to the comparison results of three washing mode, circulating washing was found to be the most suitable mode for biomass removal. The monitoring results of the toluene removal performance demonstrated that the impacts of NaOH solutions with different concentrations had little difference and the toluene removal capacities could be recovered after 3 - 4 days.
    Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 03/2007; 28(2):300-3.
  • Xia Huang · Peng Liang · Yi Qian
    [Show abstract] [Hide abstract]
    ABSTRACT: Sludge reduction in a conventional activated sludge (CAS) process combined with a recycled sludge reactor where Tubifex tubifex (one of Oligochaeta) was inoculated was investigated in this study. The results showed sludge production could be reduced through T. tubifex's predation on sludge in the recycled sludge reactor. The sludge reduction rate of T. tubifex (R) was from 0.18 to 0.81 mg-VSS mg-Tubifex(-1) d(-1). The sludge reduction capacity of the recycled sludge reactor E was from 650 to 1080 mg-VSS L(-1) d(-1). The optimum density of T. tubifex was 2500 mg L(-1) and the optimum sludge recycled ratio was 1. The existence of T. tubifex did not affect COD and NH(4)(+)-N removals in the process, but led to a slight decrease in TP removal. SVI almost did not change when the T. tubifex density was lower than 3300 mg L(-1). The LC50 values on T. tubifex of copper and ammonia were 2.5 and 880 mg L(-1), respectively, both of which were higher than those on Aeolosoma hemprichi.
    Journal of Biotechnology 02/2007; 127(3):443-51. DOI:10.1016/j.jbiotec.2006.07.035 · 2.88 Impact Factor
  • Source
    Yi Qian · Xianghua Wen · Xia Huang
    [Show abstract] [Hide abstract]
    ABSTRACT: China has been experiencing fast economic development in recent decades at the cost of serious environmental deterioration. Wastewater discharge, especially municipal wastewater discharge, and non-point pollution sources are becoming the major water pollution source and research focus. Great efforts have been made on water pollution control and a number of renovated technologies and processes for municipal wastewater treatment and reclamation as well as non-point pollution control have been developed and applied in China. This paper discusses the development and application of the appropriate technologies, including natural treatment systems, anaerobic biological treatment, biofilm reactors and wastewater reclamation technologies, for water pollution control in the country.
    Frontiers of Environmental Science & Engineering in China 02/2007; 1(1):1-12. DOI:10.1007/s11783-007-0001-9 · 0.75 Impact Factor

Publication Stats

2k Citations
183.95 Total Impact Points

Institutions

  • 1996–2014
    • Tsinghua University
      • • School of Environment
      • • State Key Joint Laboratory of Environmental Simulation and Pollution
      • • Department of Environmental Engineering
      Peping, Beijing, China
  • 2006
    • China University of Geosciences (Beijing)
      • School of Water Resources and Environment
      Peping, Beijing, China
    • Tongji University
      • College of Environmental Science and Engineering
      Shanghai, Shanghai Shi, China
  • 2005
    • The University of Arizona
      Tucson, Arizona, United States
  • 2004
    • Beijing Normal University
      • School of Environment
      Beijing, Beijing Shi, China
  • 2003
    • Shanghai Teachers University
      Shanghai, Shanghai Shi, China