激光散射技术及其对絮凝剂分子特性检测和性能研究

本文提出一种将激光散射技术应用于对絮凝剂性能研究的方法。综述了利用该技术可实现对絮凝剂胶本分子粒径、形态结构、粒径分布和重均分子量的精确测量，论述了激光散射技术在絮凝剂沉降性能的研究及絮凝剂改进方面的重要作用。     

过氧化钙联合絮凝剂调理污泥改善脱水性能

污泥经过CaO_2联合絮凝剂处理后,其脱水性能得到明显改善。采用改变初始pH、调理剂投加量以及改变调理剂投加顺序的方法,调理污泥改善脱水性能;采用Zeta电位、激光粒度、胞外聚合物及结合水分析对调理前后的污泥进行了表征;研究了调理剂不同投加量对污泥脱水性能的影响;探讨了不同调理剂下污泥脱水机理。结果表明:CaO_2联合絮凝剂(微生物絮凝剂或壳聚糖)明显改善污泥脱水降低污泥含水率;CaO_2联合絮凝剂调理后的污泥粒径和Zeta电位均有所减小,并且CaO_2在絮凝剂之前投加,降低幅度更加明显;先投加CaO_2,污泥层状结构会在氧化作用下发生裂解破碎,形成不规则的小絮体,使污泥破坏得更彻底;在絮凝剂之前投加CaO_2,污泥经过处理后的可溶性糖类和可溶性蛋白质的浓度增加,而结合的糖类、蛋白质及结合水的变化量却减小。因此,CaO_2联合絮凝剂可以优化污泥脱水性能,且CaO_2与絮凝剂的投加顺序对于污泥脱水有显著影响。     

投加阳离子聚合物加速UASB反应器中颗粒污泥形成

运行2个UASB反应器，研究常温低浓度进水条件下，投加阳离子季胺盐絮凝剂对厌氧颗粒污泥形成的影响。一个反应器中投加阳离子季胺盐絮凝剂（称A反应器），另一个反应器作为对照不投加絮凝剂（称B反应器）。经过196 d的运行，2个反应器中均形成了活性较高、沉降性能良好的颗粒污泥。A反应器中的污泥颗粒更多、粒径更大，粒径＞0.5 mm的污泥颗粒的百分比比B反应器的多16%～19.3%。研究结果表明，投加阳离子聚合物加速了颗粒污泥的形成，提高了颗粒污泥的产甲烷活性和沉降性能。     

含硫无机物对克雷伯氏菌NIII2产絮凝剂特性的影响

研究了含硫无机物对克雷伯氏菌NIII2发酵产絮凝剂特性的影响作用。结果表明:未外加硫或投加足量硫化钠时,NIII2菌,因易产酸,絮凝剂产量低,约2.14 g·L~(-1);而投加足够(16 mg·L~(-1),以硫元素计)硫代硫酸钠和硫酸钠时,絮凝剂产量提高,最高可达9.03 g·L~(-1)。与未外加硫相比,外加足够硫酸钠或硫代硫酸钠,能使絮凝剂中蛋白质相对含量分别提高29.8%和25%,并提高絮凝剂中总巯基、二硫键含量以及Zeta电位,致使絮凝剂粒径可广泛分布于0.5~3.3μm范围内,且大粒径分子所占比例提高,聚合度增大,从而稳定絮凝剂活性和性能。投加8.0 mg·L~(-1)絮凝剂,2 g·L~(-1)高岭土所产生的SS去除率达93%左右。NIII2菌所产絮凝剂为糖蛋白类,未投加含硫无机物或投加硫化钠时所产絮凝剂为O-糖苷键相连的糖蛋白,而投加硫代硫酸钠、硫酸钠时所产絮凝剂则为絮凝剂为非O-糖苷键糖蛋白。     

用铁泥制备高效无机絮凝剂聚硅酸铁及其絮凝性能研究

研究了以铁泥、硅酸钠为原料,制备高效絮凝剂聚硅酸铁(PSF)的方法,确定了合理的生产工艺和操作条件.并对絮凝剂PSF处理工业废水的絮凝性能进行了研究,探讨了PSF处理工业废水的反应机理.结果表明,PSF具有良好的絮凝性能,是一种比聚合硫酸铁(PFS)性能更优良的絮凝剂.     

絮凝剂对工程废弃泥浆脱水性能的影响

为了提高工程废弃泥浆的脱水效率,以毛细吸水时间(CST)为评价指标,研究了添加不同种类及不同用量的絮凝剂对废弃泥浆脱水性能的影响。结果表明,絮凝剂存在最适添加量,添加不足或过量的絮凝剂均会使絮凝效果下降。阴离子聚丙烯酰胺(APAM)具有较强的吸附架桥能力,脱水效果最好,絮体粒径大,脱水效果改善明显且添加量最少。原泥浆稀释至80%含水率后,APAM的最适添加量为60 mg·L~(-1),对应的CST值为23.4 s。CST法可作为泥浆调理沉降快速筛选絮凝剂的分析方法。     

用铁泥制备高效无机絮凝剂聚硅酸铁及其絮凝性能研究

研究了以铁泥、硅酸钠为原料，制备高效絮凝剂聚硅酸铁（PSF）的方法，确定了合理的生产工艺和操作条件。并对絮凝剂PSF处理工业废水的絮凝性能进行了研究，探讨了PSF处理工业废水的反应机理。结果表明，PSF具有良好的絮凝性能，是一种比聚合硫酸铁（PFS）性能更优良的絮凝剂。     

微生物絮凝剂絮凝机理的研究方法

微生物絮凝剂是一种新型的絮凝剂,为了为微生物絮凝剂絮凝机理的研究提供全面、系统的研究技术,对微生物絮凝剂的絮凝机理,影响絮凝产生的因素进行了综述,并结合不断发展的现代生物技术与仪器分析技术,剖析了絮凝机理的各种研究方法,最后还提出了微生物絮凝剂絮凝机理的研究方向.     

天然有机高分子絮凝剂研究与应用

本文根据物质的组分及来源对天然有机絮凝剂进行了分类,并对这三大类天然高分子絮凝剂的性能、应用、结构及研究发展概况等方面进行了论述     

中国微生物絮凝剂的生产研究现状

微生物絮凝剂具有降解性能好、应用广泛、成本低、操作简单及不会导致二次污染等优点,正日益引起人们的广泛重视.综述了微生物絮凝剂的开发研究状况,系统介绍了微生物絮凝剂的培养条件、产絮凝微生物生长的影响因素以及中国目前利用废水生产微生物絮凝剂的现状,并指出了微生物絮凝剂生产的现存问题和发展方向.     

Peak to Mean Pollutant Concentration Ratios for Various Terrain and Vegetation Cover

Many of the new particle sizing instruments utilize light scattering principles to detect and size aerosolparticles. The sensitivity of such nstruments is quite good, although extensive light shielding and focusingmethods must be used. A visible He-Ne gas laser cavity with its low gain is very sensitive to disturbances in its optical cavity and so may provide a new particle sizing approach.     

Quantitative Determination of Gaseous Nitrogen Dioxide Concentrations over Long Path Lengths by Selective Absorption of Argon Ion Laser Emission

An argon ion laser emits several laser lines In the visible region of the optical spectrum. The absorption coefficients of N0₂ at these laser emissions were measured in a multiple pass absorption cell. A differential technique, in which the ratio of the transmitted intensities of the argon laser emissions is measured, is described to determine the concentration of N0₂ in a polluted atmosphere over path lengths of several kilometers. Measurement of ratios eliminates interferences from particle scattering and thermal index gradients. Evaluation of the data taken in the 48 meter multipass cell indicates that concentrations of N0₂ less than one part per million could be determined in a 1 km optical path.     

复合型聚合硅酸絮凝剂的制备及其除浊除磷性能研究

在聚合硅酸中同时引入铁、镁或铁、钙2种金属离子,制成复合型聚合硅酸絮凝剂;研究了其除浊、除磷的最佳絮凝条件,包括絮凝剂投加量、水样pH值对浊度和磷去除率的影响;采用喹啉重量法测定了各种絮凝剂形成的絮体中磷的含量.结果表明,当铁磷摩尔比为2.5～3.0,pH值为7.0～8.5时,对浊度和磷的去除率最高,均达99.0%以上,聚合硅酸镁铁(PSAMF)絮凝剂适合用于磷回收.     

利用啤酒废水所产微生物絮凝剂处理靛蓝印染废水的研究

以啤酒废水为培养基，利用其中的碳源和能源，对复合菌群进行发酵培养，制得微生物絮凝剂。将此絮凝剂处理靛蓝印染废水．系统研究了pH、微生物絮凝剂用量和助凝剂（1?Cl2溶液）用量对处理效果的影响，得出了微生物絮凝剂去除CODCr和脱色的最佳工艺条件，并对该絮凝剂的絮凝机理进行了初步探讨。     

微生物絮凝剂的现状与前景分析

综述了传统絮凝剂在水处理中存在的缺陷以及微生物絮凝剂在水处理中的优越性，对微生物絮凝剂可能在将来取代或部分取代传统的无机及有机高分子絮凝剂作了科学的分析，并针对现今微生物絮凝剂发展的不足指出了今后的发展趋势。     

Air bubble and oil droplet interactions in centrifugal fields during air-sparged hydrocyclone flotation

The interactions of air bubbles and oil droplets in centrifugal flotation have been considered with respect to process conditions present during Air-sparged Hydrocyclone (ASH) flotation. Encounter efficiency of oil droplets with air bubbles has been found to be significantly smaller when compared to encounter efficiency of mineral particles. Collision and sliding contact times have been determined. Collision has been found to be insufficient for successful contact between oil droplets and air bubbles while sliding allows for film rupture depending on specific system conditions. Although the tenacity of oil droplet attachment to an air bubble is believed to be greater than the tenacity of a mineral particle, emulsification makes oil flotation in centrifugal devices with large dissipation of energy inefficient and hence requires the use of high molecular weight polymeric flocculants.     

Improved light extinction reconstruction in interagency monitoring of protected visual environments

The U.S. Environmental Protection Agency (EPA) published the Regional Haze Rule (RHR) in 1999. The RHR default goal is to reduce haze linearly from the baseline period of 2000 through 2004 to natural background in 2064. EPA-recommended method for estimating baseline and natural haze uses the Interagency Monitoring of Protected Visual Environments (IMPROVE) light extinction formula. The IMPROVE formula predicts light extinction from measured aerosol chemical concentrations and estimates of the relative humidity multiplier. On average, the IMPROVE formula overpredicts 6156 nephelometer days (24-hr average measured particle light scattering, bsp) of data by 25%. A new IMPROVED method that reconstructs light extinction using a concentration power law model overpredicts these nephelometer days of data by just 2%. Ignoring the 20% lowest light scattering days, this new IMPROVED formula has a 3% underprediction bias over the 4925 highest nephelometer days with light scattering > or =8 inverse megameters. For comparison, the IMPROVE formula has a 12% overprediction bias for the same days. The IMPROVE formula overprediction averages 77%, 27%, 17%, 9%, and -5% broken down by quintile from lowest to highest nephelometer measured light scattering days. The new IMPROVED formula average overprediction is 21%, -5%, -5%, -2%, and 0%. So, agreement between measured and predicted light scattering improves by modifying the current IMPROVE light extinction formula.     

聚硅酸锌铝的制备及其性能研究

以硅酸钠、硫酸锌、硫酸铝为原料，通过共聚法制备了无机高分子絮凝剂聚硅酸锌铝（PSZAS），研究了Na₂SiO₃的摩尔浓度、活化时间、Al/Si、Zn/Si 配比及絮凝剂的投加量对絮凝效果的影响，用X-射线衍射（XRD）和电子扫描电镜（SEM）对该絮凝剂的结构及形貌进行了表征。结果表明：当硅酸钠的浓度为0.4 mol/L，硅酸活化时间为2 h，Si∶Al∶Zn=1∶1∶1.5，絮凝剂投加量为20 mL/L废水时，絮凝剂的电中和能力和吸附架桥能力最强，絮凝剂对含H-酸染料模拟废水的絮凝效果最好。