环境工程技术学报

2014 Vol.4, No.6

Cover

Establishment of Stable Nitritation Process in a MBR Reactor for Treatment of High Ammonia Wastewater with Low C/N Ratio

ZHANG Li-cheng, NIU Yi, SONG Yong-hui, ZHENG Tie-qiang, TIAN Zhi-yong

2014, 4(6): 451-455. doi: 10.3969/j.issn.1674-991X.2014.06.071

Abstract(1856) PDF(1114KB)(816)

Abstract:
Taking synthetic wastewater of the high ammonia nitrogen and low C/N ratio as the influent, the membrane bio-reactor (MBR) was used to study establishment of stable nitritation process. The main parameters of the reactor were controlled as follows: the temperature of nitritation tanks was 28 - 30 ℃, dissolved oxygen (DO) was 0.5 mg/L, HRT was 12 h, pH was 7.8 - 8.0, influent ammonia concentration was 200 mg/L, COD_Cr was 40 mg/L. Under these conditions, the nitritation of wastewater with C/N of 1:5 was realized in the nitritation tanks. After 14 days, sludge age was 100 days, a stable nitrite nitrogen accumulation was achieved. When the ammonia concentration was increased to 400 and 800 mg/L, respectively, the tolerance of nitrosobacteria against shock of high ammonia load was relatively high.

Effect of Operating Voltage on Organic Acid Recovery from Butyl-acrylate Wastewater with Bipolar Membrane Electrodialysis

HU Tian, SONG Yu-dong, CHEN Ye, WANG Bai-dang, ZHOU Yue-xi, LI Jie, WANG Ya-e, CUI Jun-hua

2014, 4(6): 456-461. doi: 10.3969/j.issn.1674-991X.2014.06.072

Abstract(1698) PDF(752KB)(745)

Abstract:
A three-chambered bipolar membrane electrodialysis pilot module was used to recover organic acid from butyl-acrylate wastewater. Influence of operation voltage on the process was investigated. It was indicated that the operation voltage had significant effects on electrodialysis capacity, energy consumption and recovered organic acid concentration of the module. As the operation voltage increased from 50 V to 100 V, average current density increased from 16.91 mA/cm² to 55.22 mA/cm² linearly, and the electrodialysis duration was shortened significantly. Energy consumption for organic acid production increased from 0.10 kW·h/mol to 0.20 kW·h/mol linearly. As the operation voltage increased from 50 V to 100 V, water migrating with organic acid anion increased while that migrating with sodium cation decreased. As a result, higher organic acid concentration and lower NaOH concentration were achieved at operation voltage of 50 V.

Composition and Morphology of Fluidized Bed Fly Ashes and Its Application to Oil-water Separation Wastewater Treatment

DENG Wen-ye, XIE Yong-xin, LI Shou-zhu, ZHAO Hai-yan, Lü Ren-sheng, LIN Wei-yan

2014, 4(6): 462-466. doi: 10.3969/j.issn.1674-991X.2014.06.073

Abstract(1807) PDF(650KB)(774)

Abstract:
The composition and morphology of two kinds of circulating fluidized bed fly ash (CFBFA) in Xinjiang were investigated by X-ray diffraction, scanning electron microscope and chemical analysis methods. The CFBFA were modified by adding FeCl₃ and AlCl₃ water solution, the particle size and dosages of these modified CFBFA on the treatment efficiency of oil-water separation wastewater from Xinjiang Karamay polymer flooding oilfield were also investigated. The experiment results showed that these CFBFA has the contents of SiO₂, A1₂O₃, Fe₂O₃, CaO and MgO accounting for more than 90% of the total weight, lower content of glass phase, irregular particle shape and rough surface; the particle size of the modified CFBFA below 0.074 mm with good removal effect, the removal rate increased with the increasing of the dosage; when the dosage was 0.1 g/mL in the wastewater, the removal rate reached more than 90%.

Absorption Characteristics of Cd²⁺ by Sludge Incineration Ashes

WANG Zheng-jie, TONG Zhen-song, LU Peng

2014, 4(6): 467-473. doi: 10.3969/j.issn.1674-991X.2014.06.074

Abstract(1846) PDF(863KB)(1014)

Abstract:
The sludge incineration ashes were obtained by burning the sludge from urban sewage treatment plant. Based on the characterization of sludge incineration ashes, their adsorption of Cd²⁺ from water was studied. The results showed that the adsorption efficiency increased with the adsorption time, the amount of sludge incineration ash, and the initial pH, while the temperature had little effect. Under the optimal conditions of the adsorption time of 80 min, the sludge incineration ash amount of 10 g/L, the initial pH of 5-7 and the temperature of 30 ℃, the removal efficiency could reach more than 99% when the concentration of Cd²⁺ was below 10 mg/L. The Cu²⁺ in water had inhibition on the adsorption of Cd²⁺, while the Cr⁶⁺ had little effect. The adsorption process obeyed the Langmuir isotherm model and the physical adsorption was the main mechanism and the adsorption amount could reach 17.94 mg/g.

Analysis of Energy Conservation and Emission Reduction Potential for Green Transportation Mode of Modern Logistics

GU Xiu, ZHAO Zhi-yong, REN Zhen-hai, LI Han-dong

2014, 4(6): 474-480. doi: 10.3969/j.issn.1674-991X.2014.06.075

Abstract(1847) PDF(1028KB)(875)

Abstract:
The mechanism of energy conservation and emissions reduction of green transportation mode of the modern logistics as well as the research and application situations at home and abroad was introduced. With a case study of Beijing Sanjiadian Railway Freight Yard reconstruction, energy conservation and emissions reduction effects of green transportation mode of the modern logistics in Beijing were analyzed. The results showed that after this mode was put into use, Sanjiadian Railway Freight Yard could save 20 555 tons of coal equivalent and reduce 90.9 tons of PM_2.5 emission per year. Assuming an annual import of 15 million goods to Beijing, a saving of 883 864 tons of coal equivalent and a reduction of 3 908.7 tons of PM_2.5 emission per year could be obtained. On the basis of related statistics of the logistics industry in 2012, combined with the case study results and the effects of previous options in Beijing, the energy conservation and emission reduction potential of green transportation mode of modern logistics in China was projected. By revitalizing and reforming the fixed assets for existing idle 2 546 railway freight stations, this mode can save about 50 million tons of standard equivalent and reduce about 200 000 tons of PM_2.5 emission per year, while activating the economic development along the railways. In consequence, it can have great potential of energy conservation and emission reduction.

Application and Evaluation of Using Dust Suppressant for Reducing PM_2.5, PM₁₀, NO_x Pollution in Beijing

WANG Xin-xin, QI Xue-kui, LI Jin-sheng, MENG De-fa, SHI Jing, WU Xiao-jian, HUO Mao-qing

2014, 4(6): 481-488. doi: 10.3969/j.issn.1674-991X.2014.06.076

Abstract(2142) PDF(886KB)(1086)

Abstract:
The road dust suppressant was used to reduce the dust in the air at Kandan Bridge, Fengtai District in Beijing. The sprayed area was 0.4 million square meters. Sampling points were set both at sprayed area and non-sprayed area to monitor change of PM_2.5, PM₁₀, NO_x concentrations before and after the spraying, and the water-soluble anions and elements collected in the particulates analyzed. The results showed that the air pollution situation was improved by the way of spraying dust suppressant. PM₁₀ was reduced significantly, the restrain rate is 25.0%. PM_2.5 took the second, the restrain rate is 12.0%, and NO_x was controlled only in a short term, the rate is 20.1%. In addition, the dust suppressant was efficient for controlling certain specific anions and inorganic elements in the air.

Generation Estimation of Waste Liquid Crystal Displays (LCDs) in China and Analysis of Countermeasures

ZHUANG Xu-ning, SONG Xiao-long, BAI Jian-feng, ZHANG Cheng-long, WU Wen-jie, YUAN Wen-yi, WANG Jing-wei

2014, 4(6): 489-495. doi: 10.3969/j.issn.1674-991X.2014.06.077

Abstract(1957) PDF(886KB)(1188)

Abstract:
With wide use of liquid crystal displays (LCDs), the amount of waste LCDs is increasing each year. To accurately grasp the amount of waste LCDs and its trend in the following years, the sales and discarded amount of desktop LCDs, notebooks and LCD TVs were respectively predicted by Gray Model (1, 1) and Carnegie Mellon model. The results show that the accumulated obsoleted amount of desktop LCDs, notebooks and LCD TVs in 2014-2020 will be 1 089.15 million units, and the amount for reuse and recycling will be 707.95 and 169.22 million units, respectively. The amount for storage will be 300.51 million units and the final discarded amount will be 515.89 million units. To solve the problems of waste LCDs recovery and treatment, it is imperative to establish more efficient recovery management system and future develop industrialization technologies.

Study on Inspection Method of Imported Waste Plastics Suspected of Municipal Solid Waste

HAO Ya-qiong

2014, 4(6): 496-501. doi: 10.3969/j.issn.1674-991X.2014.06.078

Abstract(2342) PDF(898KB)(1321)

Abstract:
The municipal solid wastes (MSWs) were occasionally falsified for waste plastics in customs declarations, or through other illegal ways such as the concealed entrainment in waste plastics, to entered China. There was no inspection standards, procedures or guidelines of the MSWs found in China, and there was no inspecting methods of the MSW reported either. In order to better block the MSWs out of the country and combined with the inspection practices of MSWs that were falsified for waste plastics, the inspection method, process and conclusions of the MSWs falsified for waste plastics in customs declarations were systematically introduced. The characteristics of these kinds of MSWs were described and some revision suggestions provided.

Effects of Flue Gas Desulfurization (FGD) Gypsum on Desalination of Reclaimed Tidal Flat Soil

LI Xiao-ping, LIU Xiao-chen, MAO Yu-mei, CHEN Xiao-hua

2014, 4(6): 502-507. doi: 10.3969/j.issn.1674-991X.2014.06.079

Abstract(2347) PDF(748KB)(978)

Abstract:
Soil desalination of reclaimed tidal land by natural processes of rain washing and plant community succession needs several decades. Using flue gas desulfurization (FGD) gypsum as soil amendments can accelerate this natural process of desalination to within a couple of years by replacing exchangeable sodium (Na⁺) with calcium ions (Ca²⁺). Field experiments in a reclaimed tidal land located at Chongming Island of Yangtze River Delta had been conducted with FGD gypsum at rates equivalent to 0, 15, 30, 45, 60 t/hm² since 2011. The results showed that under the condition of 1 050 mm annual precipitation and two years after FGD gypsum treatment, the desalination effect of top soil (0-30 cm) was significant, and degree of soil alkalization measured as exchangeable sodium percentage (ESP) decreased by 53%. Species number and coverage of herbaceous plants increased with increasing rates of FGD gypsum (P＜0.05). Instead of dominated species reed, some halophytic herbs like Suaeda glauca, Herba taraxaci, Artemisia lavandulaefolia, and even non-halophytic Medicago sativa and Alternanthera philoxeroides were found in the 1 m×1 m quadrats. Survival rates of woody plants on higher FGD gypsum treatments were also significantly higher than that of controls (P＜0.05). It is expected that safe levels of FGD gypsum can be applied effectively to remediate saline soil of reclaimed tidal lands on a large scale.

New Ideas on Water Transfer and Pollution Treatment Based on Artificial Diversion in Taihu Lake

CHEN Kai-qi, QI Chang-jun, LI Wei, TAO Jie

2014, 4(6): 508-513. doi: 10.3969/j.issn.1674-991X.2014.06.080

Abstract(1877) PDF(835KB)(966)

Abstract:
The ecological treatment measures and methods in the Taihu Lake were analyzed and summarized, and the numerical simulation method adopted to establish a two-dimensional plane hydrodynamic and water quality model. According the simulated results of different dominant wind direction combinations of southeast, northwest and northeast, the flow field variation regularities and streamline variation forms of the Taihu Lake were analyzed. Under the new idea of reducing invalid closed circulation system and improving the contaminant exchange rate through artificial diversion, the construction of diversion dike with the combination of sludge dredging, waterway dredging and landscaping engineering in the Taihu Lake was proposed, which could barrier the invalid endless loop system forced by wind, organize and guide the water flow, promote water cycle, and then improve the clean-up effective significantly. The results show that it plays an obvious role in promoting contaminant exchange rate of the Taihu Lake. Among the five diversion dike schemes, Scheme 5 is the optimal one with most obvious improvement of the contaminant exchange rate.

Pollution Characteristics and Evaluation of Surface Sediment Nutrients in Dongting Lake

ZHANG Guang-gui, HUANG Bo

2014, 4(6): 514-519. doi: 10.3969/j.issn.1674-991X.2014.06.081

Abstract(1893) PDF(815KB)(995)

Abstract:
In order to explore the spatial distribution characteristics and pollution status of surface sediment nutrients in Dongting Lake, sediment samples at nine representative sampling stations were collected in February of 2012 and April of 2013, and contents of organic matter(OM), total nitrogen(TN) and total phosphorus(TP) in the sediments of each station were measured. The results show that the contents of OM are 1.48%-4.22% with the average value of 2.06%, the contents of TN are 382-2 217 mg/kg with the average value of 1 340 mg/kg, and the contents of TP are 142-716 mg/kg with the average value of 294 mg/kg. Compare with other lakes or reservoirs in China, the contents of OM and TN in Dongting Lake are in the middle level, its endogenous load should not be ignored. The spatial distribution of OM content is similar to that of TN, generally in the order of South Dongting Lake >East Dongting Lake> West Dongting Lake, while TP content is generally in the order of East Dongting Lake > West Dongting Lake > South Dongting Lake. The C/N ratios are 6.1-14.8 with the average value of 10.2. From the point of biological deposition, the OM in surface sediments of Dongting Lake predominantly originates from zooplankton and phytoplankton. Organic index and organic nitrogen assessment results show that Dongting Lake sediment environment is relatively good, overall in clean to just clean category.

Characteristics of Polychlorinated Biphenyl in the Air and Soils from Pearl River Delta, China

DIE Qing-qi, NIE Zhi-qiang, HE Jie, LIU Feng, HUANG Qi-fei, TIAN Shu-lei

2014, 4(6): 520-524. doi: 10.3969/j.issn.1674-991X.2014.06.082

Abstract(1831) PDF(689KB)(1040)

Abstract:
To explore distribution of polychlorinated biphenyl (PCB) in the air and soils from Pearl River Delta, the air and soil samples were collected the concentrations of PCBs detected by GC-MS. The results indicated that the concentration of total 24 PCBs (Σ₂₄PCBs) in air ranged from 240 to 2 258 pg/m³ with a mean value of 1 243 pg/m³. In the atmosphere, PCBs existed mainly in the gas phase, and three to five chlorinated biphenyls accounted for more than 90% of the total PCBs. There had been small fluctuations of concentrations of PCBs in the atmosphere in Pearl River Delta area since 2001, indicating the possibility of release sources of PCBs in the area. The concentration of total 24 PCBs (Σ₂₄PCBs) in soil ranged from ND to 20.68 ng/g with a mean value of 3.77 ng/g. Tri-CBs and tetra-CBs are the main congeners of PCBs in soil, averagely accounting for 45% and 19% of the total PCBs. In some places, the ratio of lighter PCBs decreased, while the heavier increased.

Research Progress on the Influencing Factors of Biodegradation of Chemicals

LIN Chun-jun, LIU Ji-ning, ZHOU Lin-jun, SHI Li-li, FENG Jie

2014, 4(6): 525-530. doi: 10.3969/j.issn.1674-991X.2014.06.083

Abstract(1890) PDF(919KB)(939)

Abstract:
Biodegradation is a major way of elimination of organic chemicals in the environment. Influencing factors of biodegradation of chemical were investigated in detail. The principles of metabolism and co-metabolism, and the influences of objective factors such as temperature, pH, sludge retention time, dissolved oxygen and the chemical structure on the biodegradation modes and degradation processes were elaborated. The important role that the microorganisms and relevant enzymes played in the degradation was analyzed, and the mechanisms that the autotrophs degrade the chemicals via co-metabolism, while the heterotrophs via cometabolism and/or metabolism were elaborated. Finally, it was proposed that inherent biodegradability should be enhanced by adding growth substrate, controlling the microbial structure and mixed cultivating fungal laccase and microbial.

Research and Applications of Membrane Technology in Europe

CHEN Ya-nan, YU Miao, SHEN Zhi-peng, ZHENG Xiang

2014, 4(6): 531-538. doi: 10.3969/j.issn.1674-991X.2014.06.084

Abstract(1989) PDF(1051KB)(935)

Abstract:
Because of the geographical location and population pressure, European countries have great demands and markets for membrane technology, and they take the lead in membrane research and application in the world. It will provide a good reference for the development of membrane industry in China to understand the research and application situations and existing problems and to forest future development trends in Europe. Literature statistical analysis results showed that papers on membrane technology published on journals retrieved by SCI in European countries reached 1 109 in 2013, with obvious growth trend. France and Germany had a leading position in the field of membrane study. Results of market survey showed that microfiltration membrane and ultrafiltration membrane held dominant position in European membrane market, and their sales amount accounted for 46% and 23%, respectively. Currently, European membrane industry mainly focuses on the MBR and seawater desalination, and the application of MBR in industrial wastewater is early. The landfill leachate and food & beverage industry have a significant share of the MBR. Overall, the geographical conditions, increasingly stringent water standards and related policies and regulations in Europe provide a fine external surrounding for the application of membrane technology. Moreover, sufficient competition in the market will inspire new technologies and products with advantages, and then enlarge its share in the global membrane market. Referencing the development of European membrane market, it is necessary for China to use double adjustment measures of economy and technology, improve the membrane standards, policies and regulations, and cultivate leading enterprises to enhance the international competiveness of membrane market.

2014 Vol. 4, No. 6

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