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111.
超声-Fenton高级氧化降解染料工业废水的研究   总被引:6,自引:3,他引:3  
采用超声与Fenton高级氧化技术联合处理染料废水,取得了满意的效果。同时考察了初始浓度、初始pH值、超声时间、超声频率、超声功率、H2O2和FeSO4初始浓度等因素对其COD去除效果的影响,当超声波频率为45 kHz,功率为200 W,初始pH值为2.63,超声时间为150 min,H2O2浓度为60 mmol/L,FeSO4浓度为12 mmol/L时,染料废水COD去除率达到91.8%。  相似文献   
112.
基于响应曲面法优化烧结烟气脱硫灰改性工艺   总被引:2,自引:1,他引:1  
采用BOX-Behnken的中心组合实验设计及响应面分析方法对半干法烧结烟气脱硫灰进行改性研究,得到脱硫灰转化率的预测模型。结果表明:通过该预测模型可以很好地描述脱硫灰的转化率与反应温度、反应时间和气固比等重要操作参数之间的关系,R2=0.9903。因素分析表明,反应温度对脱硫灰的转化率影响最大,同时反应温度和气固比的交互作用与反应温度和时间的交互作用对脱硫灰的转化率的影响作用相同。利用得到的改进预测模型可以计算脱硫灰的转化率。  相似文献   
113.
China is the largest rice producing and consuming country in the world, but rice production has given way to the production of vegetables during the past twenty years. The government has been trying to stop this land-use conversion and increase the area in rice-vegetable rotation. Important questions that must be answered to determine what strategy is best for society are, “What is the reason behind this conversion?”; “Which system is more productive and which is more sustainable?”; and “How can economic policy be used to adjust the pattern of farmland use to attain sustainable development?” To answer these questions, a combined evaluation of these agricultural production systems was done using emergy, energy and economic methods. An economic analysis clearly showed that the reason for this conversion was simply that the economic output/input ratio and the benefit density of the vegetable production system were greater than that of rice. However, both energy and emergy evaluations showed that long-term rice was the best choice for sustainable development, followed by rotation systems. The current price of rice is lower than the em-value of rice produced from the long-term rice system, but higher than that of rice produced from the rotation system. Scenario analysis showed that if the government increases the price of rice to the em-value of rice produced from the long-term rice system, US$0.4/kg, and takes the value of soil organic matter into account, the economic output/input ratios of both the rice and rotation systems will be higher than that of the vegetable system. The three methods, energy, emergy and economics, are different but complementary, each revealing a different aspect of the same system. Their combined use shows not only the reasons behind a system’s current state or condition, but also the way to adjust these systems to move toward more sustainable states.  相似文献   
114.
清洁发展机制在石油行业的潜力分析   总被引:1,自引:1,他引:0  
系统分析了石油行业清洁发展机制项目的潜力,并提出了建议。在统计与石油行业相关的清洁发展机制方法学及其注册项目和温室气体减排量的基础上,给出了各方法学与石油行业的相关性。从勘探与生产、天然气与管道、炼油与化工三大领域,分析了石油行业潜在的清洁发展机制项目领域。最后,提出了对石油行业开展清洁发展机制相关工作的建议。  相似文献   
115.
Little is known about the level and content of exposure to fine particles (PM2.5) among persons who attend fireworks displays and those who live nearby. An evaluation of the levels of PM2.5 and their elemental content was carried out during the nine launches of the 2007 Montréal International Fireworks Competition. For each event, a prediction of the location of the firework plume was obtained from the Canadian Meteorological Centre (CMC) of the Meteorological Service of Canada. PM2.5 was measured continuously with a photometer (Sidepak?, TSI) within the predicted plume location (“predicted sites”), and integrated samples were collected using portable personal samplers. An additional sampler was located on a nearby roof (“fixed site”). The elemental composition of the collected PM2.5 samples from the “predicted sites” was determined using both a non-destructive energy dispersive ED-XRF method and an ICP-MS method with a near-total microwave-assisted acid digestion. The elemental composition of the “fixed site” samples was determined by the ICP-MS with the near-total digestion method. The highest PM2.5 levels reached nearly 10 000 μg m?3, roughly 1000 times background levels. Elements such as K, Cl, Al, Mg and Ti were markedly higher in plume-exposed filters. This study shows that 1) persons in the plume and in close proximity to the launch site may be exposed to extremely high levels of PM2.5 for the duration of the display and, 2) that the plume contains specific elements for which little is known of their acute cardio-respiratory toxicity.  相似文献   
116.
Certain aromatic amines generated by the decolorization of some azo dyes are not removed substantially by conventional anaerobic–aerobic biotreatment. These aromatic amines are potentially toxic and often released in the wastewater of industrial plants. In this study, the fate and transformation of the naphthylaminesulfonic azo dye Reactive Black 5 (RB5) during different phases of a sequencing batch reactor were investigated. The major products of RB5 decolorization during the anaerobic phase include 2-[(4-aminophenyl)sulfonyl]ethyl hydrogen sulfate (APSEHS) and 1-2-7-triamino-8-hydroxy-3-6-naphthalinedisulfate (TAHNDS). During the aerobic phase, APSEHS was hydrolyzed and produced 4-aminobenzenesulfonic acid, which was further degraded via dearomatization. TAHNDS was transformed rapidly via auto-oxidation into TAHNDSDP-1 and TAHNDSDP-2, which were not further removed by the activated sludge during the entire 30-day aerobic phase. In contrast, different behaviors of TAHNDS were observed during the anoxic phase. The transformation of TAHNDS was initiated either by deamination or desulfonation reaction. TAHNDS was then converted into 3,5-diamino-4-hydroxynaphthalene-2-sulfonic acid, which was subsequently removed via ring cleavage reaction under aerobic condition. In conclusion, complete degradation of TAHNDS by activated sludge occurs only during anoxic/aerobic processes instead of the conventional anaerobic/aerobic processes.  相似文献   
117.
Novel magnetic carbonaceous bio-char was hydrothermal prepared from microalgae under different loadings of iron and its structures and surface chemistry were characterized with Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and nitrogen adsorption-desorption isotherm (BET). The morphology of bio-char changed from sheet to particle as iron loading increased and its surface area also increased. When 3.0 g of dried microalgae and 6.0 mmol iron salt ((NH4)2SO4·FeSO4·6H2O) were mixed and treated, the obtained bio-char possessing the highest amount of oxygen-containing functional groups resulted in the best adsorption performance on tetracycline (TC). This adsorption process was fitted to Langmuir adsorption isotherm and the maximum adsorption capacity was 95.86 mg/g, which is higher than other bio-char reported. The iron loading contributed to the higher adsorption capacity of bio-char, which may be due to three factors, the high surface area, more hydrogen bonding, and bridging effects of the structural Fe for TC. Our data suggest that bio-char may have more important role in stabilization of pollutants in the environment.  相似文献   
118.
通过现场实验研究了6-APA制药厂生化处理出水的臭氧氧化特性及其动力学规律。结果表明,当臭氧浓度为27.5 mg/L,气水接触时间为80 min时,COD、UV254、NH3-N和色度的去除率分别可达72.95%、73.28%、72%和96.25%,达到《发酵类制药废水工业水污染物排放标准》(GB 21903-2008)排放控制要求。拟合结果表明,在0~10、10~30和30~90 min时段内,臭氧氧化过程遵循拟一级反应,但反应速率逐渐降低。当气水接触时间为30 min时,废水可生化性可由0.1提高至0.35,采用臭氧/生物处理的联合工艺也有望使出水达到相同的排放控制要求。  相似文献   
119.
利用新型梨形筒式好氧堆肥反应器,在通风量为3.0 L/min,搅拌频率为5 min/h的条件下,就不接种微生物、接种土著菌种、枯草芽孢杆菌与酵母菌时人粪便连续投加好氧堆肥效果进行了对比。堆制20 d即2个运行周期中各堆体的温度、含水率、COD、总氮、pH值与GI等的变化表明,接种微生物可以显著提高堆体的升温速率与堆体平均温度、COD降解率、GI(P<0.01),堆肥可迅速达到完全腐熟。接种土著菌种效果最为明显(P<0.01),其后相继为枯草芽孢杆菌与酵母菌。接种土著菌种可使堆体温度在50℃以上维持18 d,第8天COD降解率达到61.17%、总氮损失率为25.75%,第6天时GI达到108.22%。  相似文献   
120.
煤基腐殖酸对外源砷胁迫下玉米生长及生理性状的影响   总被引:1,自引:0,他引:1  
为了筛选用于砷污染土壤治理的煤基腐殖酸,采用盆栽实验研究了施用不同种类和浓度的煤基腐殖酸及EDTA对外源砷胁迫下玉米株高、株鲜重、株干重、根干重、砷积累量、叶片抗氧化酶(POD,SOD和CAT)活性和脯氨酸含量的影响。结果表明,11种供试煤基腐殖酸均促进了玉米生长,提高了叶片POD、SOD和CAT活性。其中6和10号腐殖酸可降低土壤砷活性和显著抑制玉米吸收和积累砷,而8和9号腐殖酸增加了土壤活性砷和显著促进了玉米对砷的吸收和累积,且不同程度地强于EDTA。除8和9号外,其余腐殖酸均可明显降低玉米叶片脯氨酸的含量。EDTA可显著促进玉米吸收和积累砷,且加剧了砷对玉米的危害。因此,8和9号供试煤基腐殖酸可以替代EDTA活化土壤砷,与植物配合以提高砷污染土壤的植物修复速度和效果,而6和10号供试煤基腐殖酸则可用于土壤砷钝化剂,以保证作物产品的安全。  相似文献   
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