混凝-活性炭-超滤工艺处理洪水的试验研究

针对洪水的水质特征,研究了混凝、活性炭和超滤膜对洪水中浊度、有机物和细菌等主要污染物的去除效果,确定了混凝-活性炭-超滤组合处理工艺.试验结果表明,该组合工艺稳定、可靠.运行期间对浊度、有机物去除效果较好,对CODMn的去除率为75%,对UV254的去除率为71%,系统出水中未检出大肠杆菌,浊度基本被完全去除,主要水质指标达到国家饮用水卫生标准.     

电凝聚－气浮工艺处理景观水的试验研究

选择电凝聚-气浮工艺,对处理景观水进行了试验研究.采用铝电极,研究了不同电流密度、电导率和pH条件下,电凝聚-气浮工艺对浊度、叶绿素a、UV254的去除效率,并与常规混凝处理效果进行了当量比较.结果表明,电凝聚-气浮工艺在处理景观水中表现出一定的优势.电凝聚-气浮工艺对叶绿素a和UV254去除率分别达到81%和56%,出水浊度低于2.6 NTU,效果优于硫酸铝和聚合氯化铝.在一定的铝离子浓度范围内,电凝聚气浮工艺产泥量低于常规混凝.     

超滤组合工艺深度处理城市污水研究

考察了4种超滤组合工艺(精滤-超滤、精滤-活性炭-超滤、精滤-活性炭-精滤-超滤和混凝沉淀-超滤)对城市污水的深度处理效果.结果表明,4种超滤组合工艺对浊度的去除率都很高,最高达92.2%,均能保证出水浊度低于1 NTU,说明超滤膜对浊度的去除效果很好;4种超滤组合工艺对有机物的去除率比较高,其中精滤-活性炭-精滤-超滤对有机物的去除效果最好;超滤膜对TN和NH_3-N的去除率比较低;4种超滤组合工艺的初始膜通量不同,精滤-活性炭-精滤工艺出水通量下降较快.     

一体化膜生物反应器处理农村生活污水试验研究

采用一体化膜生物反应器(IMBR)工艺处理农村生活污水,考察了该工艺对COD、BOD5、NH3-N和浊度的去除效果。结果表明,在水温>22℃、ρ(DO)>3.4 mg.L-1、pH在6～9的条件下,工艺对COD、BOD5、NH3-N和浊度的去除效果较好,平均去除率分别达到93.1%、95.3%、93.8%和97.9%,出水COD、BOD5、NH3-N的质量浓度、浊度分别为19～31 mg.L-1、5.1～7.8 mg.L-1、1.9～3.1 mg.L-1、0～1 NTU,水质优于GB 5084-2005要求。     

2种超滤膜在膜-粉末炭生物反应器中处理沉后水的对比研究

采用浸没式膜-粉末炭生物反应器(MABR)工艺处理模拟沉后水,考察该工艺对浊度、氮类、有机物、颗粒物的去除效果,并对比聚氯乙烯(PVC)和聚偏氟乙烯(PVDC)中空纤维膜在此工艺中的净水效果和膜污染情况。结果表面,该工艺对浊度、氮类和有机物有较好的去除效果,可以将出水浊度控制在0.2 NTU以下;挂膜成功后,PVC膜对NH_4~+-N的去除率稳定在95%以上;COD_(Mn)、DOC、UV_(254)的平均去除率分别为38.8%、34.8%、47.0%。对比分析,发现2种超滤膜的过滤性能表现基本相当,但是PVDF超滤膜的污染情况比PVC更严重。     

天津某净水厂引江水强化处理技术研究

天津某净水厂主水源为南水北调中线工程引江水,该水厂在常规工艺基础上增设预臭氧、后臭氧和活性炭强化工艺,以期进一步提升出水水质。建立小试试验装置,对以上各工艺强化常规工艺处理引江水的效果展开探讨。结果表明,絮凝剂PAC和FeCl₃的最佳投加量均为17 mg/L;在常规工艺基础上增设预臭氧或后臭氧工艺可以有效提升有机物的去除效果,增设活性炭工艺可同时提升浊度和有机物的去除效果,同时增设后臭氧和活性炭工艺强化去除浊度和有机物的作用最显著。预臭氧和后臭氧的最佳投加量均为1.0 mg/L,当原水中溴离子质量浓度高达150μg/L时,常规-后臭氧工艺、预臭氧-常规-后臭氧工艺中臭氧的投加量应调整为≤0.5 mg/L。     

超滤组合工艺出水及消毒方法

本试验研究了用超滤组合工艺处理微污染水源的效果.探讨了该组合工艺出水的安全性及消毒方法.试验中采用的预处理技术是生物接触氧化和砂滤.研究表明,水温较低时,预处理对浊度、藻类和氨氮都有较好的去除效果,但对亚硝酸盐氮和有机物的去除作用有限;超滤膜除浊、除藻效果显著.该纽合工艺出水为生物不稳定水,并且有致突变性;要制备优质饮用水应改进工艺或应用新型消毒方法.     

预臭氧化工艺处理低温低浊水的应用研究

通过进行预臭氧化-紫外/氯工艺处理低温低浊期水源的生产性试验,分别对各处理单元出水pH、浊度、DOC和UV254进行了测定。结果表明,在低温低浊期,整套工艺对浊度、DOC和UV254的平均去除率分别为93.83%、29.38%和57.20%。此外,预臭氧化单元对pH及去除浊度、DOC和UV254也有一定的影响。预臭氧化单元可有效降低UV254,但对浊度和DOC的去除效果不明显。     

大伙房汛期高浊污染二次絮凝超滤工艺研究

针对抚顺市突发强降雨导致大伙房水库原水浊度在短期之内迅速升高至982 NTU,水厂常规处理工艺难以应对高浊污染的情况,采用二次絮凝-超滤膜工艺代替原有过滤工艺作为水厂中远期工艺改造方案,对比进行了汛期过程中常规工艺和二次絮凝-超滤工艺对浊度、CODMn、细菌总数的去除效果实验。结果表明,采用二次絮凝-超滤工艺的出水水质能够满足GB5749-2006的要求,二次絮凝作为膜工艺的预处理可有效缓解膜污染,并且该工艺运行成本较低,可作为抚顺各水厂工艺改造备选方案。     

PPC强化混凝与超滤联用处理含藻水的研究

超滤膜处理含藻水,通量下降迅速,通过反冲洗难以恢复,这大大限制了超滤技术的应用范围.试验考察了超滤及PPC强化混凝和超滤联用两种工艺处理含藻水的运行状态并作了比较.结果表明,超滤及其组合工艺对浊度、藻类去除效果较好,系统出水中未检出藻类,浊度在0.2 NTU以下,PPC强化混凝.超滤工艺可提高超滤膜的通量及反冲洗效果并能改善出水水质,提高UV254捌和TOC的去除率.     

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.     

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…     

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。     

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。     

聚酰亚胺的合成法

本文评述了缩聚型聚酰亚胺的主要合成方法和近年来国际上在合成中所做的探索。