高温橡胶废气在电滤装备中的流场特性研究

为研究板式电滤装备对橡胶行业燃烧所产生高温烟气的净化效果,建立了板式电滤装备的物理模型,分析板式电滤装备内部复杂的流场特性以及不同温度橡胶烟气对装备内部电场分布和净化效率的影响,利用FLUENT对烟气温度为323~673 K时板式电滤装备的收尘过程进行了数值模拟。结果表明:在相同放电电压下,烟气的温度越高,电荷密度越低,电场强度越小,烟气中细颗粒物所受静电力越小;温度升高会增强细颗粒物与流体间的相互作用,表现在气体粘度和颗粒曳力增大,从而降低了净化效率,尤其是对粒径在1μm以下的细微颗粒物,其净化效率减小得更为明显。     

无机絮凝剂絮凝效率的研究

结合比较分析传统铝盐与无机高分子聚铝的絮凝效率差异,讨论了水解产物形态、絮凝剂投加量、环境pH值和颗粒物浓度等因素对絮凝沉降效率的影响,并分析他们与絮凝沉降机理的相互关系.提出了聚铝中Al13在电中和脱稳絮凝机理中的独特吸附优势使其成为混凝过程中最主要的絮凝剂,传统铝盐在卷扫沉降絮凝机理中良好表现使其可以作为絮凝沉降过程中的一种重要补充.     

高压脉冲电场中活性氧化铝滴滤床对印染废水脱色的效能

研究了一种新型的用于去除液相污染物的方法———高压脉冲电场中活性氧化铝滴滤床去除有机物,并考察了其对印染废水脱色的效能。结果表明在高压脉冲电场与活性氧化铝的相互作用下和其他合适的条件下亚甲基蓝去除率可达67.68%。随着电压的增加、流速的减小、初始质量浓度的减小、pH的增加和空气的通入,亚甲基蓝的分解效率都得到了增加。在脉冲电场作用下,活性氧化铝表面产生局部放电,提高了亚甲基蓝的降解率;同时放电过程也增强了氧化铝对于亚甲基蓝的吸附,二者的相互作用促进了亚甲基蓝的降解。     

水泥生产线窑头电除尘器提效改造技术

电源对于电除尘器中颗粒物荷电、能效有效利用至关重要,关系到电除尘器的收尘效率,高频电源和脉冲电源相对于传统的工频电源具有比较大的优势,在水泥工业颗粒物(PM)排放指标收严的背景下,对水泥熟料线窑头配套电除尘器实施"前电场高频电源+后电场脉冲电源的组合技术"为主,烟气调质、入口预除尘改造,及各级电场预荷电+微网捕集器等辅...     

化学与湍流团聚耦合促进燃煤细颗粒物团聚与脱除

将化学团聚与湍流团聚技术耦合,实验研究了燃煤细颗粒物在化学与湍流团聚耦合作用下的团聚与脱除效果,以及颗粒物浓度、烟气温度、团聚液喷入量与烟气流速等因素对细颗粒物团聚与脱除效果的影响规律。结果表明,典型工况下化学-湍流耦合团聚能够进一步促进细颗粒物团聚长大以及静电除尘器对细颗粒物的脱除,其作用效果优于单独的化学与湍流团聚。随细颗粒物浓度的升高,团聚与脱除效率均逐渐下降,分别由49.2%与96.7%下降至35.3%与88.2%。随烟气温度与团聚液喷入量的增加,细颗粒物团聚与脱除效率均先升高后降低,并在180℃与12 L/h处达到最高值,团聚与脱除效率分别为44.7%与94.8%。随烟气流速的增加,细颗粒物团聚与脱除效率均逐渐升高,分别由30.5%与86.3%升高至50.2%与97.5%。     

热轧浊环水质改善和提高的研究

文章针对钢铁企业如何进一步优化热轧浊环水质,提出了一种好的解决方案。改变化学除油器原有的物化处理方式,即原有的在化学除油器进水口处加一种电介质的药剂与污水进入第一混合室,另一种特制的高分子油絮凝剂从化学除油器上面加进去进入第二混合室,污水在两种药剂的作用下,凝结成带粘性的絮状物质,并吸附水中的悬浮颗粒,加大自身的比重而下沉,达到固液分离的目的而净化水质。现将混凝剂加药点前移,两种药剂相隔较长一段距离,使之充分反应发挥其作用。部分大颗粒物投加絮凝剂后沉降到一次沉淀池,其它小悬浮颗粒物通过助凝剂在化学除油器内缓冲沉降,可以更好的去除水中悬浮物。     

低压直流电促进污泥好氧消化的性能研究

为了提高污水厂的剩余污泥好氧消化效率,在剩余污泥好氧消化过程中施加低压直流电场,研究不同电场条件下污泥中有机物(以MLSS表征)、总磷和沉降性(以SV表征)变化情况,探讨电场对污泥好氧消化效率的影响。结果表明:在直流电压为5 V条件下,间歇通电12 d后,通电1、2、3 h/d组,污泥的MLSS去除率分别达到39.50%、44.50%、44.75%,与未通电组相比,分别提高了33.90%、50.85%、51.69%。并且研究发现在1 h/d的电场条件下,一定周期内污泥的脱氢酶活性与细菌总数高于未通电组。实验表明低压直流电对污泥好氧消化性能有促进作用。     

海上原油乳化液在高频脉冲电场中的脱水特性研究

为了探究高频脉冲脱水法对海上原油的适应性以及脱水电参数的选取方法,本文通过实验开展了高压脉冲电场下原油乳化液电脱水特性的研究,分析了高频电场的频率、电场强度、含水率、破乳剂浓度对原油乳化液电脱水效果的影响,并通过实验结果分析了高频脉冲电场对海上原油脱水特性的影响规律,同时通过回归分析方法确定了原油在电脱水过程中最优电参数的选取方法。研究结果表明:在高频脉冲电场下,脱水前期在较低电场频率下,脉冲电场强度和频率对脱水效果的影响并不明显;在较高电场频率下,随着电场强度的增大,原油乳化液在脱水初期的脱水效果越好。当脱水进入中后期,原油脱水效果随着电场强度的增大而增大,随着频率的增大而降低;该回归分析方法可根据原油的物性参数确定电脱水过程中电场强度、频率的选取范围,实现对电脱水效果的预估计,保证脱水电场的稳定性,提高电脱水效率与脱水质量。     

电场控制火焰中细颗粒生成及分布的研究进展

以碳黑为主的燃烧源可吸入颗粒物的形成与控制是关系地球环境及人类健康的重要问题.目前对该课题的研究主要集中在颗粒生成后的控制方法上,而对如何在燃烧源内部控制颗粒物的生成尚处在初步探索阶段.介绍了电场对火焰中细颗粒控制的影响因素,对国内外研究现状进行了评述,并从生成、团聚和污染物协同控制三个方面总结了以往实验研究的成果.研究表明,在电场作用下,碳黑颗粒的质量浓度最高可减小90%;而在电场和催化金属的作用下,则可生成结构紧凑的碳纳米管束.最后提出了进一步研究的重点和方向.     

脉冲电场作用下液滴数值模拟研究

根据高频脉冲电场中乳状液破乳的相关研究,拟通过对液滴在脉冲电场中变形、破裂以及聚并研究,设计水滴静电聚结实验样槽,并运用comsol软件进行脉冲电场数值模拟,建立液滴在脉冲电场作用下的理论模型。通过模拟结果发现,电场的临界电场强度在350～500 k V/m之间时,液滴的拉伸接近纺锤形且达到拉伸极限,同时对电场中变形因素进行分析,形象的描述了液滴在电场中的变形,为电场破乳提供研究基础。     

氢气纯度分析方法准确性的探讨

ONACCURACYOFANALYSISOFOFHYDROGEN1前言我公司目前应用的氢气纯度分析方法有两种,一种是爆炸反应法,另一种是焦性没食子酸吸收法。几年来,人们对两种分析方法的准确性曾有过褒贬不一的评论。这里我们也谈谈自己粗浅的观点。2爆炸法测定氢气纯度一定量的氢气样品与适量的空气之均匀混合物因反应后生成液体水而引起气体体积减少,减少的体积等于参加反应气体体积之和。其中l／3为氧气,2／3为氢气。根据氢气取样量和反应前后混气体体积之差,以及氢气在反应中的体积比例关系,可计算出样品的氢气纯度。计算公式式中：A一混…     

COMPARISON OF METHODS OF ANALYSIS OF GYPSUM1

The different analytical methods proposed for the evaluation of gypsum have been subjected to an experimental test. A combination method, consisting of a fusion with KHCO₃ and determination of CaO by KMnO₄ titration, the SO₃ by Andrews method of titration of BaCrO₄ has been found to give very reliable results with the least consumption of time.     

SEDIMENTATION OF BINARY MIXTURES OF PARTICLES OF UNEQUAL DENSITIES AND OF DIFFERENT SIZES

A model is developed for the sedimentation from a suspension of two particle species of unequal densities and of different sizes. The composition and the thickness of various layers in the sediments are predicted using graphical and analytical methods. The model predictions were in excellent agreement with experimental results, when the particle size ratio was ≥ 108. When size ratio of the particles was 2.60 and 4.31 the agreement occurred in about 50 percent of the cases.     

HEASUREHENT OF INSTANTANEOUS RATES OF LOSS OF VOIATILE COMPOUNDS DURING DRYING OF DROPS

A novel technique serves to monitor instantaneous rates of loss of a volatile solute from a suspended drop during drying. A highly sensitive electron capture detector is used to monitor concentrations of SF6 released into a flowing gas stream from a suspended, drying drop. Simultaneously, the appearance and morphological development of the drop are monitored with a video camera. This provides the wherewithal of relating instantaneous rates of loss of the volatile solute to particular events during the development of particle morphology.

Initial experiments have been carried out with drops of aqueous solutions of glucose, sucrose, maltodextrin and coffee extract. The results clearly display the onset of the volatiles-retentive selective diffusion phenomenon. There is also substantial loss of the volatile component later in the drying process, when the drops undergo repeated ex ansion, bursting and cratering due to the formation of internaf bubbles. These experiments appear to be the first quantitative demonstration of major losses accompanying changes in drop morphology.     

ANALYSIS OF RECENT MEASUREMENTS OF THE VISCOSITY OF GLASSES

Viscosity of Simple Soda-Silicate 500° to 1400°C Comparison of the results given by English with those of Washburn, Shelton and Libman, indicates a discrepancy in the absolute values of log₁₀ viscosity amounting to 0.6, those of Washburn et al., being relatively too high. If correction for this is made, the isothermal curves of log₁₀ viscosity as a function of soda content are smooth up to 50% Na₂O, showing no inflection. The observations as a function of temperature T are all represented within accidental error by an equation of the type where all three constants vary regularly with the composition. Change of Viscosity of Glass (6SiO₂, 2Na₂O) due to Molecular Substitution of CaO, MgO and Al₂O₃ for Na₂O The effect is clearly brought out by plotting (from the results of English) the change of log₁₀η due to the substitution as a function of temperature. The curves each show a sharp bend at a temperature between 840° and 1050°C, which is designated the aggregation temperature T_a. If we divide these curves by the corresponding percentage substituted, we get curves for each oxide which are straight and parallel below the aggregation temperatures, the slopes (increase of change of log₁₀η per 100°C) being −0.056 (CaO), −0.055 (MgO), −0.018 (A1₂O₃) per per cent oxide substituted. For substitution of 1/2 molecule the slopes are −0.325 (CaO), −0.23 (MgO) and −0.18 (Al₂O₃) per 100°. At the aggregation temperature the change of log₁₀η per per cent is a minimum, 0.03 to 0.06 for CaO, 0.12 for MgO, 0.07 for Al₂O₃. Evidence of Aggregation in Glasses, from viscosity Measurements The sharp bends in the plots of change of log₁₀η due to substitution of an oxide for Na₂O, suggest the beginning of molecular aggregation at these temperatures. These aggregation temperatures are close to the devitrification temperatures, but the effect on the viscosity curves cannot be due to actual devitrification since it does not change with time. Taking the aggregation temperatures as equal to devitrification temperatures, additional isotherms are roughly sketched into the equilibrium triangle of the system Na₂O-CaO-SiO₂. Change of Viscosity of Glass (4SiO₂, 2Na₂O) due to of Substitution of B₂O₃ for SiO₂ The change of log₁₀η (from the results of English) is plotted as a function of temperature, and also the change of log₁₀η per per cent B₂O₃. The curves are more complex than for the substitution for Na₂O.     

环氧树脂羟基值测定方法的研究

利用乙酸酐、吡啶和浓硫酸混合的乙酰化试剂测定环氧树脂中羟基值含量的方法具有操作简便、滴定终点明显和分析结果误差小等优点。     

骑式摩托车油箱喷涂工艺的改进

面对日益激烈的市场竞争,摩托车油箱外观质量越来越成为影响销售的因素之一。文章介绍了改进工艺后的油箱涂装,该涂装体系提高了油箱外观的丰满度,降低了油箱涂装的生产成本。     

茶多酚提取方法进展

本文综述了国内外现有茶多酚提取方法的现状以及近期的研究进展，并对其优缺点进行了评价。这将有助于中低档茶的综合利用和茶多酚的进一步开发应用。     

几种针状焦性能对比

针状焦分石油系和煤系两大类,这主要取决于针状焦的原料来源。在同一系列中由于原料不同和工艺条件不同 ,针状焦的各自性能也不相同。针状焦是生产超高功率石墨电极和高功率石墨电极的主要原料 ,针状焦的性能对石墨电极的质量有至关重要的影响。所以对针状焦性能以及其对石墨电极质量影响的研究十分必要的。以下是常用的几种进口针状焦和国产针状焦的性能对比。１原料性能分析对比原料试样包括４种针状焦 ,其中两种为进口针状焦：三菱针状焦和新日化针状焦;另两种为国产针状焦：鞍山针状焦和锦州针状焦。其中除锦州针状焦是石油系针状焦外…     

用两个形状指数表征粉煤灰颗粒形貌的研究

引用两个形状指数表征颗粒形状的概念,即先将颗粒形状近似为椭圆,再将椭圆图像分离:以圆为基准的颗粒宏观形状指数δ;以光滑椭圆为基准的颗粒轮廓凹凸度,即微观形状指数ζ。分析和发展了近似椭圆模型。并运用图像分析仪对粉煤灰、水泥样品进行实验。结果表明,粉煤灰颗粒的两个形状指数δ和ζ都大于水泥颗粒。证明粉煤灰颗粒的球形度、表面光滑度优于水泥,而且,随着粒径增大,δ和ζ呈下降趋势,表明磨制颗粒越粗。(?)粒形状越不规则。文中还运用近似椭圆模型再现了颗粒的模拟图像。