自来水厂氨氮的活性炭深度处理

以佛山沙口水厂北江水源水为进水，考察了活性炭吸附（GAC）和臭氧．生物活性炭（O3-BAC）两种深度处理方法对氨氮的去除效果。结果表明：在低氨氮浓度下，GAC和O3-BAC对氨氮的平均去除率均为40％，最大去除率均为74％，BAC处理后的出水中三氯甲烷浓度较GAC的出水浓度低，而GAC处理成本低于O3-BAC，建议优先采用GAC工艺；在高氨氮浓度时，预氯化条件下如果控制沉淀池出水余氯≤0．1mg／L，则可以采用O3-BAC工艺除氨氮，适宜的氨氮浓度范围是0．59～0．62mg／L。     

适宜松花江源水特性及生物增强的活性炭优选

为选择出一种适宜松花江水源水生物强化的活性炭,利用3种活性炭(XYK、YM和GAC15)构建了生物增强活性炭(BEAC)和普通生物活性炭(BAC)工艺体系。以经过常规处理后的松花江水为进水,研究了活性炭类型对BEAC和BAC工艺去除有机污染物效能的影响、停留时间和臭氧含量对工艺的影响以及活性炭类型对功能菌生物量及生物活性的影响。结果表明,富含中孔的新型炭(XYK)净水效能最优,更适宜生物强化,启动期间B-XYK对COD_(Mn)和UV_(254)的最大去除率分别为86.65%、93.00%。停留时间25 min、臭氧投加量2.5 mg/L时出水COD_(Mn)达最低,但其对去除UV_(254)的影响较小。     

硝酸铁改性活性炭对六价铬离子吸附性能研究

利用硝酸铁改性和无改性两种活性炭吸附六价铬离子探究吸附时间、溶液pH值、两种活性炭投加量对去除效果的影响。结果表明:颗粒活性炭(GAC)和硝酸铁改性活性炭(Fe-GAC)对六价铬离子的吸附效果均随着时间的增加而增加;GAC和Fe-GAC吸附效果均随着投加量的增加而增加,当吸附剂投加量为5 g/L时,去除率分别为65.41%和73.03%;p H值在4～10的范围内GAC和Fe-GAC的吸附效果均随着pH的升高而降低,pH为4时,吸附效果最好,去除率分别达到81.05%和83.99%;二者均为单分子层吸附;Fe-GAC吸附效果优于GAC的原因为改性后酸性含氧官能团增加,表面酸性增强,表面极性增强。     

湿法冶金MVR废水中溶解性有机溶剂和萃取剂的去除

研究了不同种类颗粒活性炭(GAC)对湿法冶金MVR废水中特定有机物的去除效果和去除机理。结果表明:相比于Fenton法以及硅胶、硅藻土、膨润土吸附法,颗粒活性炭吸附法对废水中特定有机物的去除率最高,超过90%。GAC对废水中特定有机物的吸附符合Freundlich模型,属于优惠吸附。其中,优适煤制GAC的吸附能力最大,饱和吸附量达到35.98 mg/g(以TOC计),在最佳工况下其对有机物的去除率超过95%。     

化学预氧化/生物活性炭去除微污染原水中氨氮

以松花江水为研究对象，比较研究了高锰酸盐、高铁酸盐和臭氧三种氧化剂预氧化与生物活性炭（简称BAC）联用对微污染原水中NH4^＋-N去除效果。试验结果表明：高锰酸盐／生物活性炭（简称P／BAC）、高铁酸盐／生物活性炭（简称F／BAC）、臭氧／生物活性炭（简称0／BAC）三种工艺按硝化能力的强弱排序为：F／BAC〉P，BAC〉0／BAC。P／BAC、F／BAC对原水的NH4^＋-LN浓度变化表现出较强的适应能力，对NH4^＋-N的绝对去除量的平均值可达到1．75mg／L、2．20mg／L；NH4^＋-N的平均去除率为51％和64％。而O／BAC工艺对进水NH1^＋-N浓度的变化较为敏感，处理效果波动较大；绝对去除量的平均值为0．73mg／L；NH4^＋-N的平均去除率为21％。在原水NH4^＋-N浓度变化的较大范围内，三种工艺最后出水中NO2^--N浓度都低于进水；在原水NH4^＋-N浓度突然升高较大时，P／BAC、F／BAC出水中的NO2^--N出现少量的积累，而几天后又能恢复稳定运行状态时的低浓度出水。     

反应条件对颗粒活性炭吸附亚氯酸盐的影响

采用烧杯试验探讨了水溶液中颗粒活性炭(GAC)对亚氯酸盐(ClO-2)的去除特点。结果表明:GAC投加量越大,去除率越高;当投加比大于1∶1、反应120 min时,去除率可达100%;ClO-2初始浓度小于5 mg/L时,受GAC表面与溶液中ClO-2浓度差的影响,ClO-2去除率随初始浓度增加而迅速升高;在pH的影响下,会改变GAC表面的电性,酸性条件下带正电,促进GAC对ClO-2的去除,反之碱性条件下抑制ClO-2的去除;GAC吸附ClO-2为自发吸热的物理吸附反应,温度低于20℃时受温度影响较大,温度在20℃以上时,几乎不影响ClO-2去除效果;搅拌强度对ClO-2去除基本不产生影响,只需要GAC与ClO-2充分接触即可;粒度主要影响去除速率,充分反应的条件下,粒度对ClO-2去除效果影响较小。     

臭氧—生物活性炭工艺预处理海水试验研究

采用臭氧-生物活性炭(O3-BAC)工艺进行长期去除实际海水有机污染物试验研究.结果表明,O3-BAC工艺可有效去除海水中的有机污染物,系统运行稳定,反冲洗对BAC去除有机物影响不大.对有机污染较严重的海水,臭氧投加量3～6 mg·L-1、氧化接触时间30～60 min、水温10.5～29.0℃、BAC滤柱HRT为1h情况下,O3-BAC 工艺对TOC、DOC、CODMn、UV254以及浊度的平均去除率分别在38％、34％、55％、55％、95％以上,出水可作为反渗透膜海水淡化的进水.     

改性活性炭对邻苯二甲酸二丁酯吸附性能研究

利用硝酸改性和无改性两种活性炭吸附邻苯二甲酸二丁酯(DBP)。探究实验温度、溶液pH值、两种活性炭投加量及天然有机物(NOM)对DBP去除效果的影响。结果表明:活性炭投加量M=0.12g、实验温度T=35℃、pH值为9.0为实验最佳条件,无改性活性炭和30%HNO3改性活性炭对DBP去除率能达到92.92%和89.53%;低浓度活性炭存在的情况下,NOM分子的存在会大幅度影响活性炭对DBP分子的吸附,但随着活性炭浓度的上升,该影响并不显著。     

载铜活性炭对含酚废水的吸附性能

采用载铜活性炭(Cu/GAC)吸附含酚废水。考察吸附效果、动力学、工艺条件以及再生次数的影响。结果表明:相比微波辐射活性炭(MW/GAC)、载铁活性炭(Fe/GAC)和原始活性炭(GAC),Cu/GAC处理含酚废水的效果更显著;Cu/GAC对对硝基苯酚(4-NP)和苯酚的吸附动力学曲线均可用准二级动力学模型拟合;在酚质量浓度为200 mg/L、试验用水量为200mL、溶液初始pH值为6.0±0.2、Cu/GAC投加量为10.0 g/L、温度为25.0±0.5℃、反应时间为120 min的优化条件下,4-NP和苯酚的去除率分别达到95.2%和89.5%;炭的投加量、酚溶液的初始质量浓度和溶液初始pH对Cu/GAC处理含酚废水均有较显著的影响;经6次再生后,Cu/GAC仍保持较好的去除能力。     

生物活性炭工艺出水浑浊度和颗粒物的研究

利用在线浊度仪和颗粒计数仪监测生物活性炭(BAC)滤池进出水水质,结果表明经单独水反冲洗的BAC滤池,达到浑浊度和颗粒物的稳定去除需要2～3h。在过滤成熟期内BAC滤池对浑浊度和颗粒物有进一步的去除,浑浊度去除率为10%～30%,颗粒物去除率为15%～60%。初滤水的浑浊度和颗粒数明显高于正常过滤,颗粒数与异养菌数量有较好的相关性,表明颗粒物上可以附着大量的异养菌,是BAC滤池出水异养菌平板计数(HPC)结果升高的一个影响因素。     

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。     

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.     

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.     

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…     

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。     

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.     

酚醛树脂热降解动力学研究

用热失重非等温法对不同甲醛,苯酚魔鬼洋比的酚树脂进行了热降解动力学研究。结果表明,甲醛,苯酚摩尔比为１．５时,酚醛树旨的热发活化能最高。耐热性最好。     

剪力对梁变形影响的分析

本文用材料力学的分析方法,导出了一个计入剪力时梁的挠曲线的微分方程式。为了估计剪力对梁变形的影响,在集中力作用下梁内剪力用一个单值连续的反三角函数表示。由能量法确定了截面因子数值之后,定量地给出计入剪力时梁变形的分析结果。其结果和弹性力学的结来是一致的。     

热塑性塑料熔体质量流动速度测量不确定度的评定

本文分析了聚丙烯熔体质量流动速率测量过程中不确定度的来源，并对各不确定度分量进行了评估。该测量过程中所产生的测量不确定度主要来源于测量重复性。