微电解-生物滤池等耦合处理抗生素类混合工业废水

针对抗生素工业废水极难处理特点,采用"微电解+A2O法+絮凝沉淀+生物滤池"组合技术处理以抗生素类制药废水为主的混合工业废水。实验结果表明,进水COD Cr质量浓度235~667 mg/L,NH3-N质量浓度28.2~72.3 mg/L,TP质量浓度4.52~19.6 mg/L,色度为69~151倍,pH 6~9,设计流量30.0 L/h条件下,系统取得了良好的处理效果,其COD Cr、NH3-N、TP和色度的平均去除效率分别达到90.0%、94.1%、97.9%和79.4%,出水COD Cr、NH3-N、TP和色度等指标均达到《城镇污水处理厂污染物排放标准》(GB 18918—2002)一级A标准,该工艺处理效果稳定可靠,运营管理较简单。     

超滤膜在城市污水深度处理技术中的研究

本文分析了鄂尔多斯市达拉特旗污水处理厂污水中COD、NH4+-N、TP出水浓度水质特征以及经过MBR工艺处理后进出水浓度变化过程,结果表明:该工艺对COD、NH4+-N的平均去除率分别为94.78%、96.88%;试验平均出水COD浓度为31.42mg/L,NH4+-N浓度为1.99mg/L,均达到了《城镇污水处理厂污染物排放标准(GB18918-2002)》的一级A标准,可见该工艺对城市生活污水的有机污染物和氨氮有很好的去除效果。但是试验对污水中TP的平均去除率只有67.00%,平均出水TP浓度为1.84mg/L,远高于国家城市污水排放标准中的TP的排放限值。     

臭氧预处理+絮凝沉淀+BAF组合工艺在二级生化处理出水深度处理的应用

针对抗生素类工业废水难处理特点,特别是混合工业废水经二级生化处理后的尾水具有很难生化的特质,因此对二级生化处理后的尾水采用“臭氧预处理+絮凝沉淀+BAF”组合工艺进行深度处理。结果表明：依靠单纯BAF工艺处理COD去除效率平均仅为4.7%,无法达标,必须经臭氧氧化作用改变废水中某些有机物的结构和特性,使其发生开环、断链,才能进一步生物降解;臭氧预处理有效提高了二级生化出水的可生化性,且臭氧对BOD5处理效率随臭氧投加量的增加而提高,臭氧最佳投加量为20mg/L;该组合工艺对COD、NH3-N 和TP的平均去除效率为40.7%、34.4%和79.1%,出水COD、NH3-N 和TP等指标均能达到《污水综合排放标准》（GB8978—1996）的一级排放标准。该组合工艺为难生物降解的抗生素类制药为主的混合工业废水二级出水的深度处理提供了新途径。     

多种物化生化组合工艺处理印染电镀混合废水

通过"混凝+预处理曝气+预处理沉淀+A2/O生化法+物化"组合工艺对污水处理厂废水进行处理,对COD、TP、TN、NH3-N等测定数据进行分析,评价污水处理厂运行效果.结果表明:COD、TP、TN、NH3-N的平均去除率分别为97％、96％、70％、97％,出水各项指标的平均值分别为:COD浓度为46 mg/L、TP浓度为0.06 mg/L、TN浓度为8 mg/L、NH3-N浓度为0.6 mg/L,出水满足《城镇污水处理厂污染物排放标准》(GB 18918-2002)中的一级A标准要求,在进水浓度低于设计值的情况下,出水污染物浓度不易受进水量增加的影响.     

UCT工艺处理生活污水的实验研究

采用气提式UCT工艺处理高氨氮城市生活污水,研究了启动和稳定运行阶段系统对COD、NH⁺_4-N和TP的去除规律。结果表明,经过19 d的启动,对COD和NH+_4-N和TP的去除规律。结果表明,经过19 d的启动,对COD和NH⁺_4-N的平均去除率分别为86.17%和83.04%;稳定运行后,系统对COD、NH+_4-N的平均去除率分别为86.17%和83.04%;稳定运行后,系统对COD、NH⁺_4-N和TP的平均去除率分别为82.94%,97.84%和58.31%,出水平均浓度分别为36,1.9,5.34 mg/L,COD、NH+_4-N和TP的平均去除率分别为82.94%,97.84%和58.31%,出水平均浓度分别为36,1.9,5.34 mg/L,COD、NH⁺_4-N均达到GB 18918—2002《城镇污水处理厂污染物排放标准》一级A排放标准。70%的COD在厌氧区和缺氧区被利用,进水中较高浓度的NH+_4-N均达到GB 18918—2002《城镇污水处理厂污染物排放标准》一级A排放标准。70%的COD在厌氧区和缺氧区被利用,进水中较高浓度的NH⁺_4-N对COD去除没有影响,好氧区采用大曝气量去除高浓度NH+_4-N对COD去除没有影响,好氧区采用大曝气量去除高浓度NH⁺_4-N,硝化效果较好,NH+_4-N,硝化效果较好,NH⁺_4-N最高去除率为99.73%,基本实现NH+_4-N最高去除率为99.73%,基本实现NH⁺_4-N零排放。在UCT工艺中,高氨氮生活污水有利于缺氧区的反硝化除磷,排泥能显著降低出水TP浓度。     

UASB+两级接触氧化+混凝沉淀处理豆制品加工废水

介绍了UASB+两级接触氧化+混凝沉淀组合工艺处理豆制品加工废水的工程实例。运行结果表明,该工艺处理效果稳定,出水平均COD、BOD5分别为64、20 mg/L,SS、NH3-N平均质量浓度分别为39、9 mg/L,出水水质达到污水综合排放标准(GB 8978-1996)排放标准一级标准。     

兼氧-两级A/O-“UF+RO”膜分离-Fenton氧化工艺处理化学合成制药废水

采用兼氧-两级A/O-"UF+RO"膜分离-Fenton氧化工艺处理化学合成制药废水,在进水COD平均约6 420 mg/L、NH3-N质量浓度平均约109 mg/L的情况下,处理出水水质达到化学合成类制药工业水污染物排放标准(GB 21904-2008)新建企业水污染物排放标准,COD和NH3-N的平均去除率分别为98.3%、86.2%。     

水温对抗生素制药废水处理效率的影响

采用A2O法-生物滤池-絮凝沉淀耦合技术处理以抗生素类制药工业废水为主的混合工业废水,在不同水温下进行实验,考察水温对污水处理效率的影响. 结果表明,当水温10.0~36.8℃、进水化学需氧量(CODcr)和氨氮(NH3-N)及总磷(TP)浓度分别为183~785, 20.7~76.2和2.47~33.7 mg/L、设计流量为30.0 L/h时,CODcr, NH3-N和TP等污染物的平均生物去除率分别达64.6%, 55.7%和84.4%,出水CODcr, NH3-N和TP等指标全部达到《污水综合排放标准》(GB8978-1996)的一级排放标准. 水温变化对CODcr, NH3-N和TP等污染物的去除效率影响很小,10℃时微生物仍具有较高的代谢速率. 耦合工艺对水温变化的缓冲能力强,为严寒地区污水高效处理提供了新途径.     

高密度沉淀池/BAF工艺处理生活污水的应用

武汉市某临时污水处理厂设计规模为2×10~4 m~3/d,采用高密度沉淀池/BAF处理工艺,处理出水用作清水补给明渠,详细介绍了该工程的工艺流程、设备参数及运营情况。经过4个月的运行调试,结果表明,在进水平均COD为78.8 mg/L,进水NH3-N、TP平均质量浓度分别为26.5、2.6 mg/L的情况下,出水平均COD为14.2 mg/L,出水NH3-N、TP平均质量浓度为2.6、0.3 mg/L,出水指标稳定达到城镇污水处理厂污染物排放标准(GB 18918—2002)一级A标准。该工艺具有运行稳定、占地面积小、耐冲击负荷能力强、自动化程度高、处理效率高等优点,可供相关污水处理工程参考。     

A~2/O生化法+物化法污水处理厂运行效果分析

介绍了采用A2/O生化法+物化法工艺的污水处理厂的工艺流程、主要构筑物参数,对COD、TP、TN、NH3-N等测定数据进行分析,评价污水处理厂运行效果。结果表明,污水经过处理后,COD、TP、TN、NH3-N平均去除率分别达到88.9%、89.0%、49.7%、98.4%,出水COD为17 mg/L,TP、TN、NH3-N的质量浓度分别为0.145、9.15、0.23 mg/L,满足GB 18918-2002的一级A标准要求。在进水COD低于设计条件的情况下,出水污染物含量不易受进水量增加的影响。     

Quantification of Phospholipids Classes in Human Milk

Phospholipids are integral constituents of the milk fat globule membranes and they play a central role in infants’ immune and inflammatory responses. A methodology employing liquid chromatography coupled with evaporative light scattering detector has been optimized and validated to quantify the major phospholipids classes in human milk. Phospholipids were extracted using chloroform and methanol and separated on C18 column. Repeatability, intermediate reproducibility, and recovery values were calculated and a large sample set of human milk analyzed. In human milk, phospholipid classes were quantified at concentrations of 0.6 mg/100 g for phosphatidylinositol; 4.2 mg/100 g for phosphatidylethanolamine, 0.4 mg/100 g for phosphatidylserine, 2.8 mg/100 g for phosphatidylcholine, and 4.6 mg/100 g for sphingomyelin. Their relative standard deviation of repeatability and intermediate reproducibility values ranging between 0.8 and 13.4 % and between 2.4 and 25.7 %, respectively. The recovery values ranged between 67 and 112 %. Finally, the validated method was used to quantify phospholipid classes in human milk collected from 50 volunteers 4 weeks postpartum providing absolute content of these lipids in a relatively large cohort. The average content of total phospholipids was 23.8 mg/100 g that corresponds to an estimated mean intake of 140 mg phospholipids/day in a 4-week old infant when exclusively breast-fed.     

The hydration of reactive cement-in-polymer dispersions studied by nuclear magnetic resonance

The behaviour of two novel cement-in-polymer (c/p) dispersions, namely cement-in-poly(vinyl acetate) and cement-in-poly(vinyl alcohol) upon exposure to water at room temperature was investigated by a combination of various NMR methods. The swelling, cracking, and the water ingress were monitored non-destructively using ¹H single point imaging. The hydration of the cement matrix was investigated using ²⁹Si NMR whilst ¹³C CPMAS NMR spectra allowed the quantification of the kinetics of the hydrolysis reaction of poly(vinyl acetate) into poly(vinyl alcohol). The polymer controls the rate of water ingress and swelling which in turn determines the behaviour of the c/p dispersions upon exposure to water. For the cement-in-poly(vinyl alcohol), the rates of water ingress and swelling are much faster than the hydration of the clinker whilst for the cement-in-poly(vinyl acetate) the slow rates of the two processes allow the formation of a cementious matrix which assures the stability of the sample.     

Design and function of novel superplasticizers for more durable high performance concrete (superplast project)

In this article we shall describe our quest and ultimate success in furthering our understanding of the action of superplasticizers on the rheology of cement and concrete. By specifically producing superplasticizers with varied architectures, we have been able to show the important structural features of the macromolecules that lead to a successful superplasticizer or water reducing agent. Both polycarboxylate and lignosulfonate polymers have been investigated. Using both non-reactive model MgO powders, three different types of cement blends, the adsorption behaviour and the effect on the rheological properties of these two important superplasticizer families have been used to further develop a conceptual model for superplasticizer — cement behaviour. This paper will deal mainly with the conceptual model, the materials and methods used to asses the polymer adsorption behaviour and rheological properties of the systems studied. We shall briefly describe the adsorption of the polymers onto the different surfaces and their influence on surface charge and rheology and the influence of the various ionic species found in cement pore solutions that may influence polymer-cement affinity. The key factors are shown to be the effective adsorbed polymer thickness and the induced surface charge which can be influenced by the polymer architecture, the pore solution composition and the initial particle surface charge.     

Interactions between shrinkage reducing admixtures (SRA) and cement paste's pore solution

Shrinkage reducing admixtures (SRA) have been developed to combat shrinkage cracking in concrete elements. While SRA has been shown to have significant benefits in reducing the magnitude of drying and autogenous shrinkage, it has been reported that SRA may cause a negative side effect as it reduces the rate of cement hydration and strength development in concrete. To examine the influence of SRA on cement hydration, this study explores the interactions between SRA and cement paste's pore solution. It is described that SRA is mainly composed of amphiphilic (i.e., surfactant) molecules that when added to an aqueous solution, accumulate at the solution-air interface and can significantly reduce the interfacial tension. However, these surfactants can also self-aggregate in the bulk solution (i.e., micellation) and this may limit the surface tension reduction capacity of SRA. In synthetic pore solutions, SRA is observed to form an oil-water-surfactant emulsion that may or may not be stable. Specifically, at concentrations above a critical threshold, the mixture of SRA and pore fluid is unstable and can separate into two distinct phases (an SRA-rich phase and an SRA-dilute phase). Further, chemical analysis of extracted pore solutions shows that addition of SRA to the mixing water depresses the dissolution of alkalis in the pore fluid. This results in a pore fluid with lower alkalinity which causes a reduction in the rate of cement hydration. This may explain why concrete containing SRA shows a delayed setting and a slower strength development.     

Study of the hydration of CaO powder by gas–solid reaction

Hydration of CaO powders by reaction with water vapor has been studied in isothermal and isobaric conditions. Experimental tests were performed within the temperature range of 70 °C–420 °C and with a water vapor pressure from 5 to 160 hPa by means of a thermogravimetric device. Two powders, exhibiting slight differences in their physical properties, were studied. However, for one of the powders and under some temperature and pressure conditions, the reaction is not complete. The difference of behavior between both CaO powders was interpreted by considering the effect of the morphological properties on the mechanism of growth of Ca(OH)₂.     

The influence of water removal techniques on the composition and microstructure of hardened cement pastes

The removal of water from hardened cement paste for analysis or to arrest ongoing hydration has been reported to affect the composition of hydrated phases and microstructure. The effect that arresting the hydration of hardened cement paste by replacing the pore water with acetone before drying, and by removing the water by freeze, vacuum and oven drying has on the hardened cement paste has been investigated. Two pastes were studied, a cemented iron hydroxide floc where a high proportion of ordinary Portland cement (OPC) had been replaced by pulverised fuel ash, and a pure hydrated OPC. The results showed that none of the water removal techniques caused any major deterioration in the composition and microstructure of the hardened cement pastes studied, but the pores appeared better preserved after arresting hydration using acetone quenching. Freeze drying appeared to cause more cracking of the microstructure than the other water removal techniques.     

2-(2'-咪唑偶氮)萘酚-4-磺酸的合成及其分析性质的研究

合成了新显色剂咪唑偶氮－２－萘酚－４－磺酸（ＩＡＮ－４Ｓ）,研究了试剂的离解常数及其与金属离子的显色反应。     

Influence of bleed water reabsorption on cement paste autogenous deformation

The effects of bleed water reabsorption and subsequent early age expansion on observed autogenous deformation are investigated in this research. Bleeding was induced by varying superplasticizer and shrinkage-reducing admixture dosages and by increasing the water-to-cement ratio. This research revealed that significant early age expansion occurs with increasing chemical admixture dosages and higher water-to-cement ratios, as expected, due to increasing bleeding of those samples. When samples were rotated, negligible early age expansion was observed. Thus, bleed water reabsorption is shown to be the primary mechanism causing initial expansion in sealed autogenous deformation samples. Thermal dilation and ettringite growth appear to have a minimal influence on the observed expansion. Rotating the samples during setting eliminates the potential for bleed water reabsorption and is recommended for all autogenous deformation testing.     

Comparison between surface and bulk hydrophobic treatment against corrosion of galvanized reinforcing steel in concrete

The effectiveness of bulk hydrophobic treatment against corrosion of galvanized steel reinforcement in concrete specimens with w/c = 0.45 and w/c = 0.75 was compared with that of surface treatment, even in the presence of cracks 0.5 and 1 mm wide in the concrete cover. In this case surface hydrophobic treatments were applied both before and after cracking as a preventive and a restorative method against reinforced concrete deterioration, respectively. The obtained results in terms of water absorption, electrochemical measurements, chlorides penetration, and visual observations carried out on reinforced concrete specimens during the exposure to wet–dry cycles in 10% NaCl solution showed that bulk hydrophobization is the most effective treatment in improving the corrosion resistance of galvanized steel reinforcements in concrete also in the presence of cracks. Surface hydrophobization is very effective just in the first few exposure cycles to the aggressive environment and when used as a restorative method which is able to cancel the deleterious effect of cracks only 0.5 mm wide.     

Effect of plasma treatment of polymeric tape carriers on wetting behaviour of aqueous ceramic tape casting slurry

Due to environmental and health aspects, aqueous ceramic slurries are preferred to traditional organic solvent systems in tape casting. An important obstacle associated with the high surface energy of water is poor wetting of aqueous ceramic slurries on polymeric tape carriers. Therefore, we measured the contact angles of an aqueous epoxy-based ceramic slurry on polyethylene terephtalate (PET), polypropylene (PP), polymethyl methacrylate (PMMA), and aluminium-coated polyethylene terephtalate (PET-Al) films and investigated approaches to improving their wetting. We evaluated the effect of plasma treatment of the tape carrier surface on the wetting behaviour and compared it with the effect of adding non-ionic amphiphilic surfactants to the ceramic slurry. The treatment of the tape carrier surface by low-temperature plasma substantially improved the wetting behaviour of aqueous ceramic slurry. The lowest contact angle of 31° was obtained on the PET film. Although the addition of non-ionic surfactants improved both the wetting behaviour of the slurry and the detachment of the polymeric carrier from the ceramic tape even better than the plasma treatment of the carrier surface did, the plasma-treated carriers still present a useful alternative to the surfactants. In the case of the plasma-treated PET carrier the surfactants could be fully eliminated and potential drawbacks related to the use of surfactants could be prevented.