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页岩砖生产过程中用城市污泥为部分原料的试验研究 总被引:3,自引:0,他引:3
研究了利用城市污泥为部分原料生产页岩砖的生产试验。实验研究结果表明,在页岩粉中加入质量百分比为10%干污泥,烧结成砖,砖的各项性能符合国家标准,不仅可以节约燃煤和矿物资源,提高砖的隔热保温性能,而且可以大量资源化处置利用城市污泥。 相似文献
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城市污泥为掺料烧结砖的生产性试验研究 总被引:2,自引:1,他引:1
进行了城市污泥为部分原料生产烧结砖的生产性试验。结果表明:污泥掺量在6%和5%之内的页岩及粘土烧结普通砖,强度等级分别达到MU10和MU15(GB5101-2003)以上,均可作为承重砖体使用。污泥掺量在5%之内的页岩烧结空心砌块,强度等级为MU3.5(GB13545-2003),可作为填充墙(或隔离墙)使用。研究结果还表明:4.45%泥掺量页岩烧结普通砖热导率为0.295 W/(m·K),较普通页岩砖0.312 W/(m·K)明显降低;4.45%干污泥掺量页岩空心砌块墙体传热系数为1.33 W/(m2·K),满足《夏热冬冷地区居住建筑节能设计标准》(JGJ 134-2001) 1.5 W/(m2·K)的要求,节能效率提高11.3%,墙体隔热保温性能得到显著改善。 相似文献
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污泥中的重金属是影响污泥处置利用的重要因素,污泥制砖可以有效固结重金属。采用污水厂污泥与页岩按一定配比混合制备烧结砖,通过毒性浸出实验,研究烧结砖对重金属的固化程度以及重金属浸出稳定性,从而评定烧结制砖的安全性。结果表明,在浸出液为中性和酸性条件下,Cu、Cr、As和Pb的浸出浓度基本保持稳定,浸出时间的影响不大,而Zn的初始浸出浓度相对较大,最终逐渐降低;碱性条件下,Cr、Cu和Pb的浸出浓度随时间变化不大,而Zn和As的浸出浓度则在浸提时间内无明显变化规律;但不同p H浸出液下的重金属浸出浓度均远低于国家限值,污泥制砖重金属固化效果好,安全可靠。 相似文献
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以城市污泥为掺料制备烧结砖 总被引:3,自引:0,他引:3
以城市污泥为部分原料制备烧结砖,对不同烧成温度下不同污泥掺量的烧结砖的物理、力学性能进行了详细分析。结果表明,污泥可用于制备烧结砖,当污泥掺量≤12%,烧成温度为1 100℃时,烧结砖物理力学性能均符合烧结砖标准要求。此外,实验以污泥掺量为12%的烧结砖,烧成温度为1 100℃为例,进行了重金属毒性浸出实验,以考察烧制污泥砖对重金属的固化作用,进而评定污泥制砖的安全性。结果表明,经过高温焙烧,大多数重金属浸出毒性都显著降低,且符合规范要求,不会对环境造成危害。其中,重金属固化效果最好的为Zn,最差的为Cr。 相似文献
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《环境工程学报》2017,(3)
城市污水处理过程中产生大量的剩余污泥,污泥处理处置问题已经成为制约整个污水处理行业健康发展的瓶颈问题。实验以城市污泥为研究对象,采用兰炭粉末对城市污泥进行调理研究其过滤脱水性能的改善并通过Zeta电位、扫描电镜分析探讨了兰炭粉末调理污泥的机理。实验结果表明:当兰炭粉末的投加量为250%时,污泥过滤比阻由原泥的1.47×l0~(13)m·kg~(-1)显著下降到1.82×lO~(11)m·kg~(-1)滤饼含水率从87.81%降到了61.33%,兰炭粉末能够显著改善污泥的过滤脱水性能;当投加150%兰炭粉末时,上清液的浊度由原泥的14.11 NTU迅速降到了4.76 NTU,随着投加量的继续增加,上清液浊度基本上维持在3.00·1.50 NTU之间,兰炭对污泥絮体颗粒具有一定的吸附、絮凝作用;兰炭粉末调理污泥的机理是依靠构建骨架在污泥中形成大量渠道和空隙的刚性框架结构,在压滤过程中阻止泥饼压缩和保持泥饼的高通透性,能够很好地改善污泥脱水性能。兰炭粉末作为煤系固体废物,既可以调理城市污泥有效改善其脱水性能,又可以有效地将干污泥的低位热值从12.91 MJ·kg~(-1)明显提高到22.47 MJ·kg~(-1)(投加兰炭粉末250%调理),为污泥的热值回收提供条件,带来良好的环境、经济和社会效益。 相似文献
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《环境工程学报》2016,(2)
通过实验考察了直接利用城市污泥及其焚烧灰作为原料,采用2步烧结法工艺,烧结制取陶粒的可行性,并分析了工艺条件和物料配比对陶粒产品的吸水率和密度等性能指标的影响。实验结果表明,在不添加其他任何添加剂的情况下,城市污泥及其焚烧灰可以直接用于烧结制取陶粒。在物料配比为(1∶1~2∶1)和烧制条件(900~1 050℃)下焙烧5~20 min,可以获取不同性能的陶粒产品(吸水率为45.32%~4.11%、密度为1.67~0.84 g/cm3)。物相分析进一步表明,1 050℃是污泥灰物相发生变化的主反应温度。这为实现采用一种原料源(污泥及其污泥灰渣)制备陶粒的资源化利用方式提供了尝试。 相似文献
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Árpád Ambrus 《Journal of environmental science and health. Part. B》2013,48(3):435-442
Abstract A computer model was used to take random samples from primary sample populations obtained from field trials to simulate the uncertainty of sampling for residue analysis of plant commodities and soil. The results indicate about 40%, 30% and 20% relative uncertainty when random samples of size 5, 10 and 25 are taken respectively, from a single lot. Therefore the sample size should be the same for establishing and enforcing legal limits. 相似文献
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不同泥源对厌氧氨氧化反应器启动的影响 总被引:2,自引:1,他引:1
采用2套上流式生物膜反应器,分别接种少量厌氧氨氧化污泥和大量硝化污泥,考察其对厌氧氨氧化反应器启动的影响。污泥接种入反应器后,测得接种厌氧氨氧化污泥的反应器(R1)内MLSS为0.22 g/L,另一个反应器(R2)MLSS为2.7 g/L。与直接接种厌氧氨氧化污泥相比,R1经过72 d的运行才显现出厌氧氨氧化特性。经过114 d的培养,前者氮去除速率由0.23 kg/(m3.d)提升到5.29 kg/(m3.d),总氮去除率大于89%;R2的氮去除速率由0.01 kg/(m3.d)提升到1.1 kg/(m3.d),总氮去除率大于84.6%。说明普通污泥启动需要一个较长的筛选过程,直接接种少量的厌氧氨氧化污泥比接种普通的污泥能够更快启动厌氧氨氧化反应器。 相似文献
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介绍了电解法生产次氯酸钠的原理 ,并在原有生产工艺的基础上进行了重新设计和对设备的重新选择、改造 ,得出了各个工艺参数的最佳值 ,生产出高品质的次氯酸钠 相似文献
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Janusz A. Pudykiewicz Anna S. Koziol 《Atmospheric environment (Oxford, England : 1994)》1998,32(24):5541
The most common technique used for numerical simulations of tracer mixing is that of the numerical solution of the advection–diffusion equation with the unresolved fluxes parameterized using the similarity theory. Despite correct predictions of the overall directions of transport, models based on a numerical solution of the advection–diffusion equation lack sufficient accuracy to correctly reproduce the coupling of mixing with small scale processes which are sensitive to the microstructure of the tracer distribution. The objective of this paper is to revisit the basic formalism employed in numerical models used to investigate atmospheric tracers. The main mathematical method proposed here is the theory of kinematics of mixing which could be applied effectively for simulations of atmospheric transport processes. At the beginning of the paper, we introduce simple mathematical transformations in order to demonstrate how complex topological structures are created by mixing processes. These idealistic flow systems are essential to explain transport properties of much more complex three-dimensional geophysical flows. An example of the application of the kinematics of mixing to the analysis of tracer transport on a planetary scale is presented in the following sections. The complex filamentary structures simulated in the numerical experiment are evaluated using some commonly applied statistical measures in order to compare the results with the data published in the literature. The results of the experiment are also analysed with the help of simple conceptual models of fluid filaments. The microstructure of the tracer distribution introduced in the paper is essential to increase our understanding of atmospheric transport and to develop more realistic parameterizations of small-scale mixing. The presented results could also be used to improve calculations of the coupling between microphysical processes and tracer mixing. 相似文献
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造纸废水混凝处理中SFT助凝替代性研究 总被引:1,自引:0,他引:1
中小造纸厂废水处理常用PAC作混凝剂 ,PAM作助凝剂。由于PAM成本很高 ,影响了处理设备的投运率。用超细滑石粉 (SFT)替代PAM助凝 ,与混凝剂PAC配合 ,其混凝处理效果基本相当 ,但是处理成本降低 0 .10元 /m3 。由于SFT属环境无害材料 ,不会给排泥带来二次污染 相似文献
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活性炭三维电极法对印染废水的处理研究 总被引:4,自引:0,他引:4
对三维电极方法处理印染废水进行了实验研究,初步探讨了活性炭三维电极法处理印染废水的机理,对影响处理效果的各种要素,如反应时间、槽电压和pH值等进行了条件实验,得出了活性炭三维电极法处理印染废水的最佳运行条件为:停留时间120-180 min,槽电压25~30 V,进水pH值6.5~7.5。结果表明,该反应器能有效地降低废水色度,有较高的COD去除效率,并能提高印染废水的可生化性。 相似文献
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以松木木屑为原料,在自制的小型流化床上,开展了生物质热裂解温度、生物质粒径和进料速率对生物油产率的影响实验研究.结果表明,在热裂解温度分别为450、475、500、525和550℃条件下,当热裂解温度为500℃时,生物油产率最高,平均产率达到53.33%(质量百分比).反应温度越高,炭产量越低,不可冷凝气体产量越高,气体发热值越高;粒径<1 mm的生物质其粒径对生物油产率影响不大;生物质进料速率增加时,生物油产率增加.本研究为生物能的利用提供了新的途径. 相似文献
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Evaluation of the presence of drugs of abuse in tap waters 总被引:1,自引:0,他引:1
A total of seventy samples of drinking water were tested for non-controlled and illicit drugs. Of these, 43 were from Spanish cities, 15 from seven other European countries, three from Japan and nine from seven different Latin American countries. The most frequently detected compounds were caffeine, nicotine, cotinine, cocaine and its metabolite benzoylecgonine, methadone and its metabolite EDDP. The mean concentrations of non-controlled drugs were: for caffeine 50 and 19 ng L−1, in Spanish and worldwide drinking water respectively and for nicotine 13 and 19 ng L−1. Illicit drugs were sparsely present and usually at ultratrace level (<1 ng L−1). For example, cocaine has mean values of 0.4 (Spain) and 0.3 ng L−1 (worldwide), whereas for benzoylecgonine, these mean values were 0.4 and 1.8 ng L−1, respectively. Higher concentrations of benzoylecgonine were found in Latin American samples (up to 15 ng L−1). No opiates were identified in any sample but the presence of methadone and EDDP was frequently detected. Total mean values for EDDP were 0.4 ng L−1 (Spain) and 0.3 ng L−1 (worldwide). Very few samples tested positive for amphetamines, in line with the reactivity of chlorine with these compounds. No cannabinoids, LSD, ketamine, fentanyl and PCP were detected. 相似文献