2017 Vol. 7, No. 1

Display Method:
Experimental study on copper recovery from berberine wastewater by crystalline precipitate-adsorption resin combined process
CUI Xiaoyu, SHAN Yongping, ZENG Ping, HE Xuwen
2017, 7(1): 1-6. doi: 10.3969/j.issn.1674-991X.2017.01.001
Abstract(1977) PDF(1649KB)(1613)
Abstract:
A combination of crystalline precipitation and resin adsorption process was adopted for the recovery of copper contained in berberine production industrial wastewater. Optimized conditions were studied by batch experiments. The crystal structure of produced precipitate as tribasic copper chloride (TBCC) was evaluated by XRD analysis. The results showed that under the pH of 7.0-9.0, over 99.9% copper was recovered by crystalline precipitation process. The composition of basic copper chloride precipitation could meet with national standards(GB/T 21696-2008) of feed-grade after water washing. After a following ion exchange treatment the effluent copper ion concentration was less than 1.0 mg/L. On the basis of the bench-scale test, a pilot scale test was carried out. The results of pilot scale tests certified the effect of this combined process. This process could recover the copper resource from pharmaceutical industrial wastewater and, at the same time, improve the pH from lower than 1 to higher than 7, which would be beneficial to the comprehensive treatment of pharmaceutical wastewater and the meeting of discharge standards.
Enhanced coagulation and nitrification for nitrogen and phosphorus removal from corn starch wastewater
GUO Xiaoya, NIAN Yuegang, YAN Haihong, YIN Qin, GAO Peng, CHEN Guangwei
2017, 7(1): 7-8. doi: 10.3969/j.issn.1674-991X.2017.01.002
Abstract(2059) PDF(1679KB)(1547)
Abstract:
Considering the limit-exceeding problems of nitrogen and phosphorus in current cornstarch wastewater treatment, two solutions were put forward: one is to remove some pollutants by enhanced flocculation at the pretreatment stage; the other is to utilize the effluent of primary sedimentation tank as a carbon source for denitrification. The wastewater was treated by ferric chloride, aluminum sulfate, chitosan, and sodium alginate as flocculants, and optimum conditions were determined by single factor coagulation tests. The results showed that the ferric chloride was the suitable flocculant for treatment of cornstarch wastewater. When the dosing quantity of ferric chloride coagulant was 0.40 g/L, pH was 4, temperature was 35 ℃, the removal rates of TP, SS, TN and CODCr were 93.5%, 94.8%, 10.8% and 10.7%, respectively. The pollutant degradation characteristics and dynamic characteristics were studied by sequencing batch reactor with the effluent of primary sedimentation tank as the carbon source for denitrification, and Monod equation and piecewise zero-order kinetic model were used to fit the experimental data. The results showed that $NO_{2}^{-}$-N accumulation was found in the denitrification process, and the accumulation rate was 61%. The predicted values of simulation parameters using Monod equation fit well with the measured data, and the maximum degradation rates of $NO_{3}^{-}$-N、$NO_{2}^{-}$>-N and $NO_{x}^{-}$-N were 24.21, 12.78 and 15.97 mg/(g MLVSS·h) respectively. The concentrations of $NO_{x}^{-}$-N was also fit well by piecewise zero-order kinetic model and the denitrification rates of stage 1 and 2 were 16.09 and 8.71 mg/(g MLVSS·h) respectively.
Analysis of water footprint and water resources carrying capacity in Shenyang in 2005-2012
JIANG Shihui, PENG Jianfeng, SONG Yonghui, LIU Ruixia, ZHANG Moli
2017, 7(1): 15-23. doi: 10.3969/j.issn.1674-991X.2017.01.003
Abstract(2029) PDF(2870KB)(1499)
Abstract:
Based on the theory of water footprint, the water footprint and water resources carrying capacity were calculated to measure the real utilization of water resources in Shenyang for 2005-2012. The relationship between socioeconomic system and water resources system was contrasted and analyzed by the water footprint and water resources carrying capacity. On the basis of water footprint indicator, an evaluation index system of coupling coordinative degree was constructed, and the temporal difference of coupling degree and coupling coordinative degree in Shenyang analyzed by using the Capacitive Coupling Model. The results indicated that water footprint in Shenyang showed decreasing trend in 2005-2012. The annual average of water footprint was about 3.654×10 9 m 3. The virtual water consumption of agriculture was the key component of city water footprint. The difference in population and dietary habits was the main reason for increase of the virtual water consumption. In terms of the basic indexes of water resources carrying capacity, the utilization of water resources in Shenyang was unsustainable. The population growth and economic development had caused the water resources shortage. The coordination result of coupling degree and coupling coordinative degree showed that the water resources carrying capacity system was in the state of antagonism, and the system of "water resource, society and economy" was in the state of mild disorder during the last years except 2005.
Upgrading of high naphthenic acid crude oil wastewater treatment
YANG Xiongqiang
2017, 7(1): 24-31. doi: 10.3969/j.issn.1674-991X.2017.01.004
Abstract(2002) PDF(2769KB)(1336)
Abstract:
The wastewater COD concentration (3 000-5 500 mg/L) from a refinery refining high naphthenic crude oil is far greater than the design index (2 400 mg/L) of the wastewater treatment plant (WWTP), resulting in incompliance of the discharge standard. By using gas chromatography/mass spectrometry (GC/MS), the effluents of each process unit were analyzed, showing that organic matters in wastewater, such as naphthenic acid, indene ketone, cycloalkene (cycloalkanes) and nitrogen heterocyclic compounds, were difficult to be effectively removed, leading to exceeding of COD discharge standard. Referring to large number of literatures and combining the field pilot test, the processes of biological aerated filter (BAF), hydrolysis acidification and ozone catalytic oxidation were adopted for upgrading of the WWTP. The upgraded processes include oil separation + two-stage flotation + BAF + hydrolytic acidification + A 2O biochemical treatment + membrane bioreactor (MBR) + ozone catalytic oxidation + activated carbon. After upgrading, the operational data showed that the BAF could enhance the anti-shock loading performance of the WWTP, greatly decrease the organic pollutant load, with effluent COD<2 000 mg/L, and make A 2O biochemical treatment and subsequent processing units run stably under the original design conditions. The hydrolytic acidification could enhance biochemical B/C ratio of BAF wastewater, and serve as "water quality stabilizer". The COD removal rate of ozone oxidation tower loading with catalyst was as high as 69.4%, and the effluent COD met the requirements of discharge standards (<60 mg/L).
Preparation of nano-crystalline La0.4Sr0.6MnO3 and its photocatalytic performance
WEI Chao, XIA Xunfeng, WANG Jinggang, WANG Lijun, ZHANG Ying, LÜ Huiyu
2017, 7(1): 32-38. doi: 10.3969/j.issn.1674-991X.2017.01.005
Abstract(1717) PDF(3328KB)(1273)
Abstract:
Citric acid complexing method was adopted to prepare nano-crystalline La0.4Sr0.6MnO3. The material was based on metal nitrate and citric acid, processed with dissolving, evaporation, drying, calcination and milling, etc. Techniques of XRD, SEM, and XPS were used to characterize its physical chemical properties and microscopic structure. The results showed that the catalyst was conformed to cubic phase perovskite, with spherical shape and good dispersity, and the proportion of each element met with the chemical formula basically. The photocatalytic performance of the nano-crystalline La0.4Sr0.6MnO3 was explored with methyl orange (MO) under visible light. The photocatalytic activity was investigated by changing the experimental factors, such as pH of solution and oxidant. The results showed that the degradation performance of MO under the acidic condition (pH 1.4) was better than the alkaline condition, and the degradation of MO could reach more than 75% under the acidic condition. Meanwhile, nano-crystalline La0.4Sr0.6MnO3 with oxidant showed better photocatalytic activity than that without oxidant. The adsorption and photo-oxidation properties of nano-crystalline La0.4Sr0.6MnO3 were explored, and the results met with the Langmuir model and first order reaction kinetics model.
Correlation analysis based on PLS1 between PM2.5 and air pollutants in Tianjin
MIAO Yunge, WANG Jian, MA Yinhong, YANG Wen, GU Chao
2017, 7(1): 39-45. doi: 10.3969/j.issn.1674-991X.2017.01.006
Abstract(1430) PDF(1097KB)(1075)
Abstract:
The correlation analysis, PLS1 and path analysis were applied to study the direct effect five main air pollutants on the quality of PM2.5, their indirect effect on other pollutants and also the total effect in Tianjin in different seasons (291 days) of 2014.The results showed that the factors significantly related to PM2.5 were SO2, NO2 and CO in spring, O3(8 h) and CO in summer, SO2, NO2 and CO in autumn and SO2, NO2, CO, O3(8 h) in winter, respectively. Meanwhile there was a positive multicollinearity between O3(1 h) and O3(8 h) in winter. The goodness of fit R 2of PLS1 model in four seasons was 0.553, 0.323, 0.713, 0.839, respectively, which indicated that the model was reasonable. Path analysis revealed that CO was the greatest pollutant factor to PM2.5 and showed there existed obvious seasonal variations, with the total effect coefficients of 10.810, 5.587, 6.271, 12.500 in four seasons, respectively. The total effect coefficient of O3(8 h) in summer was 0.897, and that of NO2 was 0.185, 0.338 and 0.290 in spring, autumn and winter, respectively. Moreover, the direct effect coefficients of the pollutants in four seasons were higher than those of indirect effect.
Applying of geoaccumulation index to evaluate elements pollution in PM2.5 in Anshan during autumn
LI Jin
2017, 7(1): 46-51. doi: 10.3969/j.issn.1674-991X.2017.01.007
Abstract(1363) PDF(900KB)(1107)
Abstract:
The PM2.5 samples were collected at 6 monitoring sites in Anshan during autumn in 2014. The concentrations of 16 elements (Na, K, Cd, V, Cr, Mn, Ni, Cu, Zn, Pb, Al, Mg, Ca, Fe, Ba, As) in the samples were determined by ICP-OES and ICP-MS methods. The pollution status of the 16 elements was studied by Geoaccumulation Index and correlation analysis. The results showed that through the comparison of concentrations of elements from PM2.5 samples at different monitoring sites, the ratios of maximum to minimum values for Pb, Cd, C, As in PM2.5 were more than 2, the difference was greater, and especially the ration for As was up to 12.19. The ratios of maximum to minimum values for Na, K, V, Mn, Ni, Cu, Zn, Al, Mg, Ca, Fe, Ba were less than 2, exhibiting smaller difference. The results of Geoaccumulation Index indicated that the elements of Cd, Zn, Pb, As, mainly from iron and steel smelting, vehicles and tire-wear, were extremely contaminated. The relevance results showed that Cd,Zn,Pb,Cu might be from the same types of sources.
Review of treatment technologies for thermal desorption offgas
WANG Yiwen, MA Fujun, ZHANG Qian, GU Qingbao
2017, 7(1): 52-58. doi: 10.3969/j.issn.1674-991X.2017.01.008
Abstract(1932) PDF(1310KB)(1432)
Abstract:
The current research status and progress of thermal desorption offgas treatment technologies were reviewed. Four treatment technologies including condensation, adsorption, thermal combustion and catalytic combustion are used in engineering. Condensation is mainly used as a pretreatment of high concentration of organic pollutants in exhaust gas due to its low removal rate. Adsorption and thermal combustion have high removal rate of pollutants in the exhaust gas but with high cost. Catalytic combustion is generally used for purification of low concentration pollutants in exhaust gas. For developing thermal desorption equipment in line with the socioeconomic level of China, two new thermal desorption gas processing technologies including cement kiln co-processing technology and non-thermal plasma technology are proposed. The cement kiln co-processing technology is based on the principle of thermal combustion and can be used for treating thermal desorption offgas of contaminated sites around the cement plants. Non-thermal plasma technology has promising prospects with the advantages of high efficiency, low cost and no secondary pollution.
Effect of cement and activated carbon on solidification/stabilization of PAHs contaminated soil
ZHANG Mengmeng, WANG Wanfeng, MA Fujun, ZHANG Qian, GU Qingbao
2017, 7(1): 59-64. doi: 10.3969/j.issn.1674-991X.2017.01.009
Abstract(1992) PDF(885KB)(1661)
Abstract:
As a low cost and easy to operate technology, the solidification/stabilization is widely used for remediating contaminated sites. PAHs leachability and unconfined compressive strength (UCS) of cement-based solidified/stabilized materials with or without activated carbon were evaluated. When the contaminated soil was leached under three scenarios of neutral precipitation, acid precipitation, and co-disposal, the leaching concentrations of PAHs were 2.53, 2.74 and 3.88 μg/L, respectively. After treated by cement of 20% soil weight, the leaching concentrations of PAHs were 8.99, 10.12 and 10.99 μg/L, respectively under the three scenarios. The leachability of PAHs increased when contaminated soil was solidified/stabilized by cement. PAHs concentrations in leachates were in the order of co-disposal scenario>acid-precipitation scenario>neutral-precipitation scenario. When the contaminated soil was treated by 20% cement and 1% activated carbon of soil weight, the leaching concentrations of PAHs was 0.99 μg/L; the addition of activated carbon can significantly lower PAHs concentrations in leachates. 28 d UCS of solidified/stabilized materials was 1.82, 5.95 and 12.06 MPa when the contaminated soil was treated by cement of 10%, 20% and 30% of soil weight, respectively. UCS of solidified/stabilized materials increased with the adding amounts of cement. When the contaminated soil was treated by 20% cement, UCS of solidified/stabilized materials was not affected by the amount of activated carbon when adding no more than 2% of soil weight.
Oxidizing capacity of catalyzed hydrogen peroxide to petroleum hydrocarbon contaminated soil
ZHANG Qiuzi, WEI Yunxiao, JIANG Yonghai, WEI Xiaofei, WANG Fuwang
2017, 7(1): 65-70. doi: 10.3969/j.issn.1674-991X.2017.01.010
Abstract(1771) PDF(1205KB)(1378)
Abstract:
Regarding to the petroleum hydrocarbon polluted sites that are remediated with H2O2 based ex-situ chemical oxidation, the oxidizing capacity and reactive process of catalyzed H2O2 were studied with different H2O2 mass fractions and oxidant to catalyst/stabilizer ratios. It is found that hydroxyl radical and superoxide anion are the major oxidation groups. The H2O2 mass fraction of 0.50%-1.00% and the oxidant to catalyst/stabilizer ratio of 75∶1-100∶1 provide higher total petroleum hydrocarbon (TPH) degradation rate. The results demonstrated that high H2O2 concentration and low oxidant to catalyst/stabilizer ratio may lead to rapid H2O2 decomposition that reduce the contact time between oxidant and contaminant and decrease the oxidizing efficiency. In addition, it is also found when H2O2 is under rapid decomposition, it tends to oxidize hydrocarbon molecules with less carbon number.
Morphology analysis of heavy metals in soil pollution in-situ remediation technique based on phyto-mimic method
ZHOU Jianqiang, HAN Jun, XU Yuanjian, YANG Lipeng
2017, 7(1): 71-77. doi: 10.3969/j.issn.1674-991X.2017.01.011
Abstract(1998) PDF(2354KB)(1248)
Abstract:
The field remediation effect of phyto-mimic method and the changes of Cr, Ni, Zn and Fe in different forms of soil were studied, using the in situ remediation technique based on phyto-mimic method. Results showed that after three months of phyto-mimic remediation, the concentration of Cr, Zn, Ni and Fe decreased month by month, with the reduction rate for heavy metals being 17.33%, 27.03%, 31.60% and 5.17%, respectively. The morphological changes of the four kinds of heavy metals in phyto-mimic remediation are not the same. The reduction rate of soil Zn and Cr contents of different forms is as follows: acid soluble> reducible> oxidizable> residual fraction; while the reduction rate of soil Ni and Fe contents of different forms is as follows: acid soluble> oxidizable > reducible > residual fraction. The four kinds of heavy metals can be enriched in the filler and simulation blade of the phyto-mimic remediation device, and the adsorption properties of the filler will affect the content of the four kinds of heavy metals in the simulated blade.
Advances of eco-environmental remediation of mine wasteland
CHEN Wei, NING Ping, LI Huijuan, YOU Ping, ZHU Anling
2017, 7(1): 78-87. doi: 10.3969/j.issn.1674-991X.2017.01.012
Abstract(1858) PDF(843KB)(1452)
Abstract:
Mineral resources are important material bases to support Chinese social and economic development. On the other hand, mining activities have introduced severe environmental pollution and resulted in serious impacts on the surrounding environment, such as the decrease of cultivated areas, destruction of sensitive ecosystems. Therefore, the eco-environmental restoration of mine wastelands is more and more concerned by experts and government departments. The current status of mineral resources exploitation, environmental problems caused by mining activities, related policy, and current restoration situation were reviewed. Meanwhile, the characteristics and ecological restoration objectives of mine wastelands were analyzed, related substrate modification and eco-system restoration technologies introduced, and the application adaptability and advantages and disadvantages of the technologies pointed out. Finally, some potential solutions were proposed aiming at the problems such as lacking of investment funds and technologies, so as to provided reference for the ecological restoration of mine wastelands in the future.
Bibliometric analysis for removal of heavy metals from soil by leaching technology
MA Yan, LIU Xianghui, XU Dongyao, ZUO Haiqing, CHEN Jiaqi, DONG Binbin, DU Xiaoming
2017, 7(1): 88-95. doi: 10.3969/j.issn.1674-991X.2017.01.013
Abstract(2027) PDF(1848KB)(1393)
Abstract:
Soil leaching, known as a new efficient soil remediation technology, has obtained rapid development in recent years. Focusing on the field of remediation of heavy metal contaminated soil using leaching technology, relevant publications and patents were analyzed with the method of bibliometric analysis. Then on this basis, the annual trends both at home and abroad were overviewed systematically, the distribution of major research institutions, regions and countries contributing to the papers and patents analyzed, and the gap between China and the major developed countries and regions in the world discussed. In the end, it was pointed that the key technologies and hotspots in this field are the leaching process and equipment and eluting reagent.
Ecological risks and control measures of typical perfluorinated compounds PFOS/PFOA
CAO Ying, ZHANG Yahui, YAN Zhenguang, WANG Yizhe, ZHU Yan, LIU Zhengtao
2017, 7(1): 96-101. doi: 10.3969/j.issn.1674-991X.2017.01.014
Abstract(1987) PDF(862KB)(1646)
Abstract:
The two most common PFCs pollutants found in nature were perfluorooctane sulfonate (PFOS) and perfluorooctane acid (PFOA). The recommendations of environmental safety thresholds of PFOS and PFOA were reviewed at home and abroad. Based on the pollution status of PFOS and PFOA in some basins and typical areas in China, the problems of the ecological risk management of PFCs in China were analyzed. Some suggestions were proposed, including formulating the PFOS and PFOA environmental quality criteria/standards, strengthening the ecological risk assessment of typical regional PFCs, and enhancing the material substitutes monitoring, ecological toxicity supervision and substitutes risk prevention and control, etc.
Application of SLAB model in liquid ammonia leakage emergency response
YANG Jingling, LING Min
2017, 7(1): 102-106. doi: 10.3969/j.issn.1674-991X.2017.01.015
Abstract(2164) PDF(1966KB)(1489)
Abstract:
Taking the leakage of stored liquid ammonia in a factory as the research object, the SLAB model was applied to simulate the environmental emergency rescue system for the leakage accident. The consequences in adverse environment conditions (such as low wind speed in the winter) following the accident of liquid ammonia leakage were predicated by use of the SLAB model, including the concentration of immediate threat to life and health (IDLH), the permissible exposure concentration in 15 minutes, the diffusion range of the harmful substances' maximum permissible concentration in the residential atmosphere. The predicted results of the model clearly reflected the dangerous areas into which ammonia could possibly diffuse after the leakage accident. Specifically, within the areas of 0-435.8, 435.8-797.1 and 797.1-1 031.6 meters downwind from the leakage source, the ammonia ground concentrations respectively exceed IDLH, the maximum permissible concentration of ammonia in the workplace and the maximum permissible concentration of the harmful substances in the residential atmosphere, when the leakage time reaches 10 minutes. The rescue commanders can quickly comprehend the accident consequences according to the prediction, and make correct rescue programme in time.
Behavior of slagging and corrosion of biomass ash
LI Haiying, ZHANG Ze, JI Aimin, ZHAO Rongxuan, YANG Peng
2017, 7(1): 107-113. doi: 10.3969/j.issn.1674-991X.2017.01.016
Abstract(1512) PDF(1003KB)(1414)
Abstract:
The problems of slagging and corrosion of heating surface caused by biomass ash formed during the combustion of biomass were concerned. Through analyzing the characteristics of biomass ash, such as the content of element and mineral, physical and chemical properties and ash fusion, the slagging formation process and the mechanism of the heating surface corrosion were discussed. It was found that biomass slagging is caused by the following reasons. Firstly, the forming of the alkali metal sulphates and chloride decreased the fusion point and increased the stickiness in the surface of the fly ash; and then the slagging was formed on the heating surface. In addition, based on the formation of the HCl and Cl2 during high temperature, the heating surface of the boiler will be corroded owing to Fe reaction with the HCl and Cl2. According to the analysis of the influence factors on slagging and corrosion including the content of the fuels, temperature in the furnace, materials of the heating surface and so on, it was proposed that some measures such as co-firing of biomass and coal, additives in biomass, biomass fuel washed with water and metal anticorrosion on heating surface, be used to prevent the problems of slagging and corrosion.
Determination of cadmium in solid samples using solid sampling atomic fluorescence spectrometry
QIN Xiaopeng, HOU Hong, ZHAO Long, SUN Zaijin, MA Jin
2017, 7(1): 114-119. doi: 10.3969/j.issn.1674-991X.2017.01.017
Abstract(1539) PDF(1687KB)(1258)
Abstract:
The concentration of cadmium (Cd) in soils, atmospheric particles, and solid wastes was determined using a new solid sampling atomic fluorescence spectrometry (SSAFS), which was designed by Beijing Titan Instruments Co., Ltd. Nine standard soils(GBW07407, GBW07402, GBW07410, GBW07425, GBW07426, GBW07428, GBW07419, GBW07309 and GBW07418) were chosen to study the influence of sample mass on the measurements, and the standard curves were well fitted (R 2 > 0.93) in the range of 1.0-10.0 mg. When the sample mass was 10.0 mg, the detection limit and determination limit were 0.004 7 and 0.016 mg/kg, respectively. The concentration of Cd in five field samples measured with SSAFS using the seven standard curves (except GBW07418 and GBW07419) was consistent with the value measured with the inductively coupled plasma mass spectrometry (ICP-MS). However, compared with the concentration of Cd determined by ICP-MS, the concentration in atmospheric particles determined by SSAFS was much higher, and the value in solid wastes was smaller. As a result, in order to improve the accuracy of data, it was suggested that the same type of standards or standards in the studied area should be used to establish the standard curves before analyzing solid samples in some area.
Conditions optimization and application for determining concentrations of HNO3 and HNO2 in atmosphere of Beijing by annular denuders method
QI Xuekui, WANG Xinxin, ZHANG Tingting, WANG Yu, LIU Yanju, WU Yanwen, SUN Zhenquan
2017, 7(1): 120-124. doi: 10.3969/j.issn.1674-991X.2017.01.018
Abstract(1452) PDF(965KB)(1271)
Abstract:
In order to study the pollution characteristics of HNO3 and HNO2 in ambient air of Beijing City, the experiments for determining the optimal concentrations of annular denuders coatings were performed, and application study carried out in Beijing in the autumn of 2014. The results showed that when the concentration of Na2CO3 coating solution was 2%, the removal rate of acid gases in the atmosphere reached over 90%. The concentrations of HNO3 and HNO2 in air sampled in downtown Beijing were determined by the optimization approach. The concentrations of HNO3 and HNO2 in the measurement period ranged from 0.77 to 3.23 μg/m 3 and from 1.12 to 5.51 μg/m 3, with an average value of 2.33 μg/m 3 and 2.96 μg/m 3, respectively. HNO2 concentration was higher than that of HNO3 in the study area. The weak light during sampling might result in HNO2 photolysis reduction. Also, because of the sampling point nearby trunk road, the homo- and heterogeneous reactions of NOx from automobile exhaust may lead to a higher HNO2 concentration. The highest concentration of HNO3 occurred in haze day, followed by sunny day, while HNO2 had the highest concentration in haze day, which was far more than that in sunny day.