电除尘器比电阻软件测算研究与应用

为了进一步提高静电除尘器的收尘效率、降低能耗,对粉尘比电阻这一重要影响因素进行了研究。依据粉尘比电阻值定义,建立了收尘极板上粉尘层压降模型,提出了利用压降模型和伏安拟合特性曲线数学表征式来在线测算真实工况下粉尘层比电阻的实现方法。以480C型阳极板、RS芒刺阴极线极配形式进行了模拟验证实验,结果表明测算所得的比电阻数值与实际值相符。最后对现有电除尘控制系统中基于比电阻值的反馈控制方法做了简要介绍。     

不同来源溶解态腐殖酸与Cu2+作用的荧光特性

利用三维荧光等高线图以及其所确定的荧光峰荧光强度随溶液化学条件的变化，研究不同来源溶解态腐殖酸与Cu²⁺作用的荧光特性。研究结果表明：溶解态天然腐殖酸中主要存在二类发射荧光的有机物官能团能与Cu²⁺发生络合作用。位于激发波长和发射波长分别为271～281 nm和335～351 nm的荧光峰1所代表的有机物官能团是与Cu²⁺发生络合配位的主要点位；pH值为4～6时，其络合受pH值影响较显著；而受溶液离子强度影响较小。位于激发波长和发射波长分别为223～246 nm和335～371 nm的荧光峰2所代表的有机物官能团与Cu²⁺的络合作用受溶液pH值影响较小，受溶液离子强度影响较显著。溶解态商品腐殖酸荧光峰1′所代表的有机物官能团与Cu²⁺的络合作用荧光特性，与天然腐殖酸荧光峰1所代表的有机物官能团和Cu²⁺络合作用荧光特性相似，在pH值为3～7时，其络合受pH值影响较显著。     

厌氧颗粒污泥吸附去除废水中Hg2+的研究

在实验室条件下，以静态、序批的方法研究了厌氧颗粒污泥对废水中Hg²⁺的吸附特性及环境条件对其吸附能力的影响，并通过红外光谱和能谱对比手段，初步探讨了厌氧颗粒污泥吸附Hg²⁺的机理。结果表明，厌氧颗粒污泥对Hg²⁺的吸附过程符合准二级吸附动力学模型，其吸附等温线与Freundlich型拟合得较好(R²=0.9933)；pH是影响吸附的重要因素，在pH值为3～8的范围内，吸附量较大，最大为64.64 mg/g，当pH值大于8或小于3时，吸附量逐渐下降；温度对吸附也有一定的影响，但影响程度不明显。红外光谱和能谱分析表明，厌氧颗粒污泥表面功能基团对Hg²⁺的络合作用是吸附的主要机理，这些基团包括—CH、—CH₂ 、—CH₃、P—H、CO、C—N、PO、SO及C—H，同时在吸附过程中还存在一定的离子交换吸附。     

柔性集尘极应用于湿法脱硫烟气深度净化的试验研究

为揭示柔性绝缘疏水纤维织物用作集尘极材料的可行性及电场性能,为解决传统湿式静电技术由集尘极材料选择及表面水膜布置不均引发的系列问题,利用浸润质量在线监测法,得到水对柔性集尘极的毛细浸润特性;通过测量不同给水率条件下柔性集尘极电阻率及伏安特性曲线,揭示柔性集尘极表面水膜特性与静电场性能之间的耦合关系;建立小试/中试试验台,研究了柔性集尘极对燃煤脱硫烟气气溶胶污染物组分的净化性能。结果表明,水能够在柔性集尘极表面形成均匀水膜;试验工况下,柔性集尘极电场性能优于导电刚性材料,柔性集尘极对酸雾气溶胶脱除率达98%以上;中试装置出口烟气酸雾<10mg/m3、浆液滴<15mg/m3、微细粉尘<5mg/m3;工业化装置较高的烟羽透明度表明柔性集尘极实际运行性能良好。     

水环境中腐殖酸与镉离子结合作用的影响因素

通过测定不同化学条件下腐殖酸与镉离子作用后的游离态镉离子浓度及其结合率，研究各因素对腐殖酸与镉离子作用的影响。研究结果表明，pH值、离子强度、投加镉离子总浓度、腐殖酸浓度和反应温度均影响腐殖酸与镉离子的结合。pH值在4.5~6.5范围内，随pH值升高，腐殖酸与Cd²⁺的结合率增大，游离态Cd²⁺浓度减少。溶液的离子强度增大对结合反应有抑制作用。投加Cd²⁺总浓度的增大会导致结合态Cd²⁺浓度和游离态Cd²⁺浓度逐渐增加，而其结合率逐渐减小。腐殖酸浓度逐渐增大，使Cd²⁺和腐殖酸的结合率逐渐增大。在20℃~50℃范围内时，随反应温度升高，游离态Cd²⁺浓度逐渐减小，其结合率逐渐增加。     

污泥基活性炭吸附Cu2+的应用研究

以城市污水处理厂剩余污泥为原料，以ZnCl₂为活化剂制取污泥基活性炭。以此污泥基活性炭为吸附剂，对含Cu²⁺的废水进行了吸附实验研究。考察了溶液pH值、Cu²⁺的起始浓度对Cu²⁺离子吸附量的影响；利用等温吸附实验作出吸附等温线，并考察了污泥基活性炭吸附剂吸附Cu²⁺的动力学方程。实验结果表明，污泥基活性炭对Cu²⁺具有良好的吸附性能。吸附的最佳pH值为5；吸附符合Langmuir和Freundlich吸附等温方程，吸附为优惠吸附，吸附量随着吸附质溶液浓度的增加而增大；吸附平衡时间为4 h，吸附动力学符合二级动力学方程。     

天然和巯基改性沸石吸附水溶液中重金属Hg2+的特征研究

为了提高沸石对汞的吸附性，利用半胱胺盐酸盐对天然斜发沸石进行改性，制得巯基改性沸石。研究了吸附剂用量、pH值、温度、Hg²⁺浓度和吸附时间对沸石和巯基改性沸石吸附Hg²⁺的影响，并进一步研究了吸附机理。结果表明，巯基改性沸石吸附Hg²⁺受pH值、温度的影响较小，吸附机制主要是沸石表面的硫与Hg²⁺的化学反应。而天然沸石对Hg²⁺的吸附主要是离子交换作用，受温度、pH值等的影响较大，随温度的升高吸附量下降。整个吸附过程以较快的速度进行。天然沸石在吸附时间为1 h、巯基改性沸石在0.5 h时基本达到吸附平衡。吸附条件试验和Langmuir等温吸附模型都表明，巯基改性沸石对Hg²⁺的吸附能力得到了很大的提高，吸附容量由8.06 mg/g 提高到19.88 mg/g，提高了146.65%。     

满江红干体对锌离子的生物吸附

以满江红干体为生物吸附剂，研究了不同条件下对废水中Zn²⁺的净化作用。结果表明，满江红干体对Zn²⁺的吸附是一个快速的过程，前5 min的吸附量达到最大吸附量的62.9%，30 min达到吸附平衡；初始pH值对Zn²⁺的吸附有显著的影响，最适pH值为6；随着干体量的增加，吸附率逐渐提高而吸附量则降低；随着Zn²⁺初始浓度的增加，吸附率逐渐降低而吸附量则提高。满江红干体对Zn²⁺的吸附符合Langmuir吸附等温线方程，最大吸附容量达57.5 mg/g。5次吸附解吸循环实验数据表明，重复次数和再生处理对满江红干体的吸附能力没有产生显著影响。因此，满江红干体在处理含Zn²⁺废水中的重复使用是可行的。     

微波预处理对秸秆厌氧消化影响的研究

以秸秆为研究对象，比较不同的微波强度预处理作用下对秸秆厌氧消化产气特性的影响，研究日产气量、pH值、甲烷气体浓度及生物降解率4个参数的变化趋势，结果表明:微波预处理对秸秆厌氧消化有明显效果，平均日产气量由未被预处理的6.21 mL/g VS上升到 8.16 mL/g VS，上升了31.33%，达到最大日产气量时间由原来的第12 d，提前至第2～第7 d不等，最大日产气量由原来的23.43 mL/g VS上升到43.49 mL/g VS；在360～900 W范围内，微波强度越大，反应的pH值下降越快，秸秆厌氧消化最大日产气量越提前；经过微波预处理的甲烷浓度平均浓度由原来的50%提高至62%左右，其生物能范围也由未处理前的17.58 MJ/m³提高至23.46 MJ/m³，物降解率由未预处理的44.12%，提高至71.55%。     

高稳定性污泥蛋白发泡剂的发泡特性及应用研究

以污泥蛋白为实验材料，通过加入不同量的稳定剂GP-1，配制成高稳定性污泥蛋白发泡剂，并对高稳定性污泥蛋白发泡剂的发泡特性和影响因素进行研究。结果表明，以污泥蛋白10 mL、水90 mL、GP-1 0.4 g配方组合为研究对象，所制备的泡沫初始体积为770 mL，泡沫泌水时间大于15 h，泡沫半衰期大于64 h，泡沫综合发泡能力为2.2×10⁶ mL·min，泡沫的最佳搅拌时间为5 min，泡沫的泌水时间和泡沫的半衰期都是随着温度的上升而下降，在pH为3～13时泡沫稳定。经过对高稳定性污泥蛋白发泡剂发泡特性研究以及对水泥的胶凝时间、特性进行比较，研制出污泥蛋白泡沫混凝土发泡剂，并制备污泥蛋白泡沫混凝土块；结果表明，当污泥蛋白泡沫混凝土发泡剂的用量分别为0、6、6.8、7.6、8.4和9.2 mL，水泥为200 g时，制备泡沫混凝土块，其密度由2.07 g/cm³下降到0.34 g/cm³，体积由130 cm³ 上升到755 cm³；在泡沫混凝土块脱模后的第1 d、第7 d、第28 d分别称量他们的重量变化情况，结果表明，泡沫混凝土块第1 d和第7 d无重量变化，第28 d的重量明显减轻。该研究为污泥蛋白研制成为泡沫混凝土发泡剂，并应用于屋面隔热、保温建立前期基础。     

Applicability of grid-net detection system for landfill leachate and diesel fuel release in the subsurface

The grid-net system estimating the electrical conductivity changes was evaluated as a potential detection system for the leakage of diesel fuel and landfill leachate. Aspects of electrical conductivity changes were varied upon the type of contaminant. The electrical conductivity in the homogeneous mixtures of soil and landfill leachate linearly increased with the ionic concentration of pore fluid, which became more significant at higher volumetric water contents. However, the electrical conductivity in soil/diesel fuel mixture decreased with diesel fuel content and it was more significant at lower water contents. The electrode spacing should be determined by considering the type of contaminant to enhance the electrode sensitivity especially when two-electrode sensors are to be used. The electrode sensitivity for landfill leachate was constantly maintained regardless of the electrode spacings while that for the diesel fuel significantly increased at smaller electrode spacings. This is possibly due to the fact that the insulating barrier effect of the diesel fuel in non-aqueous phase was less predominant at large electrode spacing because electrical current can form the round-about paths over the volume with relatively small diesel fuel content. The model test results showed that the grid-net detection system can be used to monitor the leakage from waste landfill and underground storage tank sites. However, for a successful application of the detection system in the field, data under various field conditions should be accumulated.     

收尘区脉冲供电对电除尘器收集性能的影响

建立了双区电除尘器实验模型,研究了预荷电压、不同供电方式下极板间距、电极型式对双区电除尘器收尘效果的影响.结果表明:随着预荷电压逐渐升高,除尘效率也随之增加,双区除尘效果明显优于单区的除尘效果.脉冲供电对电除尘器的除尘性能影响明显,与直流供电相比,脉冲供电对PM25的分级效率可提高16.9%;在较高的电压时,极板间距为...     

铜污染土壤电动修复研究

应用实验方法研究了土壤重金属污染的电动力学修复方法,分析了土壤重金属污染物的迁移和变化特征。实验结果表明,在电场作用下土壤中重金属的浓度分布发生明显变化,使得大部分重金属能在电极附近富集而被去除。当实验的电场强度为0.5 V/cm时,在阳极附近土壤中铜的去除效率达到71.1%。阳极附近的pH值由开始时的6.8逐渐变小到4.4,而阴极附近则相反,由开始时的6.6逐渐增大到9.1,此外电动修复过程中电极附近的温度会发生相应的变化。     

Electrocatalytic oxidation of methyl tert-butyl ether (MTBE) in aqueous solution at a nickel electrode

This study utilized the electrocatalytic characteristics of nickel electrode to perform degradation of methyl tert-butyl ether (MTBE) in aqueous solution. Lab experiments were conducted in a spiltless bath type cell equipped with a nickel electrode as working electrode, a platinum wire as counter electrode, and an Ag/AgCl electrode as reference electrode. Effects of controlled potential, supporting electrolyte, and solution pH on the efficiency of MTBE removal were examined under the control of the constant-potential conditions. Experiment results showed that the optimum electrolytic condition was operated at 0.35 V in a 1M KOH electrolyte solution, and the initial 20 mgl(-1) MTBE was reduced by 73% within 180 min under the optimum control. As using 1M Na2SO4 and 1M KCl as electrolyte, the efficiency of MTBE removal dropped to 60% and 50% under the similar controls. Comparing with various pH controls, the strong basic condition is favorable for electrocatalytic oxidation of MTBE in the Ni-electrolytic system. The efficiency of MTBE removal showed a rising trend with increasing initial pH of the solution. The formation of a redox NiOOH/Ni(OH)2 layer on the anode surface, which was observed on the SEM image, can explain that nickel plays a mediator role on improving electrocatalytic oxidation of MTBE at 0.35 V in a strong basic condition. The by-products of MTBE degradation were identified as acetone and CO(2) by GC/MS, and the distributions of carbon atoms in acetone, CO2, and MTBE were found 22%, 51%, and 27% through the optimum control of electrochemical oxidation.     

铜污染土壤电动修复研究

应用实验方法研究了土壤重金属污染的电动力学修复方法，分析了土壤重金属污染物的迁移和变化特征。实验结果表明，在电场作用下土壤中重金属的浓度分布发生明显变化，使得大部分重金属能在电极附近富集而被去除。当实验的电场强度为0.5 V/cm时，在阳极附近土壤中铜的去除效率达到71.1%。阳极附近的pH值由开始时的6.8逐渐变小到4.4，而阴极附近则相反，由开始时的6.6逐渐增大到9.1，此外电动修复过程中电极附近的温度会发生相应的变化。     

Electrochemical degradation of Acid Blue and Basic Brown dyes on Pb/PbO2 electrode in the presence of different conductive electrolyte and effect of various operating factors

Electrocatalytic degradation of Acid Blue and Basic Brown dyes from simulated wastewater on lead dioxide anode was investigated in different conductive electrolytes. It was shown that complete degradation of these dyes is dependent primarily on type and concentration of the conductive electrolyte. The highest electrocatalytic activity was achieved in the presence of NaCl (2g/l) and could be attributed to indirect oxidation of the investigated dyes by the electrogenerated hypochlorite ions formed from the chloride oxidation. In addition, contribution from direct oxidation could also be possible via reaction of these organic compounds with the electrogenerated hydroxyl radicals adsorbed on the lead dioxide surface. In the presence of NaOH, the electrocatalytic activity of the employed anode was not comparable to that in NaCl due primarily to the absence of chloride. This indicates that dyes degradation in NaOH occurs exclusively via direct electrochemical process. However, in H2SO4, the electrode performance was poor due partially to the absence of chloride from the conductive solution. The possibility of electrode poisoning as a result of growth of adherent film on the anode surface or production of stable intermediates not easily further oxidized by direct electrolysis in H2SO4 might also be accountable for the poor performance observed in this conductive electrolyte. Optimizing the conditions that ensure effective electrochemical degradation of Acid Blue and Basic Brown dyes on lead dioxide electrode necessitates the control of all the operating factors.     

含中间层的DSA电极电催化氧化硝基苯废水的研究

为了提高难降解有机废水的可生化性，以及更高效地去除废水中的特征污染物，同时避免二次污染，利用自制的含锡锑中间层的钌钯氧化物涂层电极对有机废水中的硝基苯进行处理，并利用SEM、XRD等方法对电极中间层、表层进行微观表征。微观测试表明，基体、中间层、表层之间结合力较强，有利于增强电极寿命；水处理实验表明，电催化氧化反应体系适合高浓度有机废水的处理，由于该反应体系需要外加电解质加强传质，这在实际运用中为废水中盐度的处理提供了一种新的途径，当电流密度为20 mA/cm²、电解质浓度为10 g/L、pH=5、极板间距=2 cm时，电催化氧化体系对硝基苯具有较高的去除效率。     

Emissions of chromium (VI) from arc welding

The presence of Cr in the +6 oxidation state (Cr[VI]) is still observed in ambient air samples in California despite steps taken to reduce emissions from plating operations. One known source of emission of Cr(VI) is welding, especially with high Cr-content materials, such as stainless steels. An experimental effort was undertaken to expand and update Cr(VI) emission factors by conducting tests on four types of arc-welding operations: gas-metal arc welding (GMAW), shielded metal arc welding (SMAW), fluxcore arc welding, and pulsed GMAW. Standard American Welding Society hood results were compared with a total enclosure method that permitted isokinetic sampling for particle size-cut measurement, as well as total collection of the aerosol. The fraction of Cr(VI) emitted per unit mass of Cr electrode consumed was determined. Consistent with AP-42 data, initial results indicate that a significant fraction of the total Cr in the aerosol is in the +6 oxidation state. The fraction of Cr(VI) and total aerosol mass produced by the different arc welding methods varies with the type of welding process used. Self-shielded electrodes that do not use a shield gas, for example, SMAW, produce greater amounts of Cr(VI) per unit mass of electrode consumed. The formation of Cr(VI) from standard electrode wires used for welding mild steel was below the method detection limit after eliminating an artifact in the analytical method used.     

Electrochemical reduction of organohalogen compound by noble metal sintered electrode

1,2,3-Trichlorobenzene (1,2,3-TCB) was used as a model sample of persistent organic pollutants (POPs) which was dechlorinated by a closed electrochemical reduction system under an inert gas atmosphere. The effect of the electrode material was examined in the reaction. Dechlorination yields in different type of cathode electrodes using sintered RuO2 (major)/Pt/PdO, sintered Pt(major)/IrO2/RuO2, sintered RuO2, sintered PdO, sintered Pt, sintered PdO/Pt, sintered Pd/Pt and plain Pd plate were 91%, 81%, 59%, 96%, 53%, 97%, 82% and 70% respectively, at reaction times of 60 or 120 min. The reaction was exothermic after initially starting at room temperature. This electrochemical reduction system was friendly technology for environment using cation exchange membrane, supplying sodium ions from sodium hydroxide solution as anolyte. Trace amounts of dichlorobenzene, as products of stepwise dechlorination, were observed with different pathways, depending on the electrode material. Electrodes with Ru and Pd were selective mainly for meta-position dechlorination, while those with Pt groups selective mainly for ortho-position (o-position) dechlorination. A PdO sintered electrode had an especially high selectivity for meta-position (m-position) dechlorination. The results suggest that dechlorination is an electrocatalytic reduction in this cation supply system.