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1.
垃圾焚烧飞灰胶凝活性初探   总被引:1,自引:0,他引:1  
飞灰是生活垃圾焚烧后烟气除尘器收下的物质 ,其主要成分属CaO—SiO2 —Al2 O3 —Fe2 O3 体系 ,与目前常用的高炉矿渣、粉煤灰等辅助性胶凝材料非常接近 .通过实验 ,研究了飞灰的物理性质以及其掺入水泥后对硬化水泥浆体力学性能和水化机理等的影响 ,初步探讨了飞灰作为辅助性胶凝材料利用的可行性 .研究表明 ,飞灰的水化反应活性较低 ,飞灰的掺入在一定程度上延缓了水泥的水化过程 ,但其水化可以形成适量钙矾石 ,从而对强度发展较为有利  相似文献   

2.
成分对垃圾飞灰熔融过程重金属迁移的影响   总被引:7,自引:0,他引:7  
熔融处理可以有效控制垃圾焚烧飞灰中的重金属污染 ,飞灰成分对重金属的迁移特性有重要影响 ,研究了飞灰成分和碱度对 6种重金属迁移固化的影响规律。在自行设计的小型实验台上开展飞灰熔融实验 ,飞灰碱度在 0 .6~4 .6范围内变化。为评价多种重金属综合固化效果提出一个简明的评价模型。在 14 6 0℃、空气气氛下熔融处理时 ,加入Ca O后除了 Cd外各种重金属的固化率均下降 ,而加入 Si O2后多数金属固化率增加。存在一个临界碱度值可以实现重金属的最佳固化 ,实验得到的临界碱度在 1.0附近  相似文献   

3.
垃圾焚烧飞灰冶金烧结处理工序   总被引:1,自引:0,他引:1  
垃圾焚烧飞灰是公认的危险废弃物,必须对其进行有效处理。鉴于冶金烧结过程具有相似的高温熔融环境,提出采用冶金烧结法处理垃圾焚烧飞灰。对垃圾焚烧飞灰进行造球成型与铁浴熔融分离固化实验,结果显示:添加8%水泥和1%稳固剂的飞灰造球成型性好,在养护实验8~11d,飞灰球团抗压强度在600~700N/球,达到贮存、运输要求;铁浴熔融能有效地分离固化飞灰中重金属元素,90%以上的Mn、Fe和70%以上Cr、Cu进入铁相,熔渣浸出毒性均能达标。研究结果为冶金烧结法处理垃圾焚烧飞灰的工业应用提供了可行性验证。  相似文献   

4.
生活垃圾焚烧飞灰的污染特性   总被引:34,自引:2,他引:34  
垃圾焚烧会产生含重金属等污染物的烟气净化系统飞灰 .根据上海浦东新区生活垃圾焚烧厂飞灰的重金属和溶解盐测试分析结果 ,以及国外对飞灰中二口恶口英等有机污染物的研究 ,分析了我国垃圾焚烧飞灰的污染特性 .研究结果表明 :按我国危险废物浸出毒性鉴别标准 ,飞灰属危险废物 ;Pb ,Cd ,Hg和Zn是飞灰中的主要重金属污染元素 ;可浸出部分Cd主要以离子交换态和酸溶态形式存在 ,而Pb和Zn主要以酸溶态形式存在 ,因此在酸性环境条件下飞灰的重金属污染风险会显著增加 .飞灰溶解盐为 2 2 .1% ,主要为氯化物 ,其存在会增大其它污染物的溶解度 ;飞灰处置时可能会污染地下水体 .飞灰含少量二口恶口英和呋喃等有机污染物 ,有污染环境和危害人类健康的风险  相似文献   

5.
为无害化处理焚烧飞灰,并实现CO2减排,利用中国城市生活垃圾焚烧飞灰作为吸附剂,固定CO2,并稳定垃圾中重金属。考察水分添加量、CO2分压等因素并进行热重-差热实验、X射线衍射及连续浸取实验。结果表明:干燥飞灰可吸收其自身质量3%的CO2;水分添加量大于10%时,纯CO2吸收效果较好;CO2的吸收及其碳酸化过程使飞灰中C a(OH)2转化为C aCO3,同时飞灰中可交换态Pb质量的40%左右转化为碳酸盐结合态而得以稳定。  相似文献   

6.
城市垃圾焚烧飞灰理化性质及处理技术   总被引:2,自引:0,他引:2  
焚烧法处理城市垃圾已在世界先进发达国家广泛采用,而城市垃圾焚烧处理引起的二次污染问题已引起人们的高度关注,特别是垃圾焚烧飞灰的安全有效处置成为急需解决的环境和社会问题.通过分析垃圾焚烧飞灰的物理化学性质,对目前国内外城市垃圾焚烧飞灰处理技术进行了系统分析和讨论,归纳出目前国内垃圾焚烧飞灰处理的主要方式为安全填埋、固化稳定化和重金属提取,提出适合于中国垃圾焚烧飞灰无害化处理的途径和方式:开发先进的焚烧炉,加强对入炉垃圾的控制:研究稳定效果好、处理成本低的化学稳定剂以及有效的重金属分离提取方法,以减少垃圾焚烧飞灰中重金属造成的二次污染.  相似文献   

7.
固体度物资源化处理和综合利用工程属于国家鼓励类项目,生活垃圾焚烧飞灰在水泥领域中的资源化利用是当前国内外研究的热点,但由于垃圾焚烧飞灰是一种特殊的危险废物,决定了生活垃圾焚烧飞灰资源化利用项目的环境影响评价工作不同于一般的建设项目.该文从工程分析、污染防治对策、环境风险评价等方面,对该类项目环境影响评价中应注意的问题做了初步探讨.  相似文献   

8.
城市垃圾焚烧飞灰的污染特性分析   总被引:1,自引:0,他引:1  
城市垃圾焚烧处理以其具有明显的减量化、无菌化、资源化等优点,近年来得到了较广泛的应用.然而,垃圾焚烧后产生的飞灰中含有大量的水溶性盐分和重金属,如果处理处置不慎就会对环境产生二次污染.为合理有效的处理城市垃圾焚烧飞灰,并为其资源化利用提供科学依据,需对其中污染物的特性进行分析,本文研究了城市垃圾焚烧飞灰的粒径分布,pH值,水溶性盐分含量,不同粒径上重金属的含量及不同粒径上的重金属对总量的贡献率.结果表明:飞灰的粒径分布近似正态分布,80%以上颗粒集中在54~280 μm之间,粒径小于54μm和大于280μm的颗粒所占的质量分数都很少,还不足3%和15%;飞灰呈强碱性,pH值高达12以上;飞灰样品中水溶性盐分的含量较高,可达2%以上;易挥发性的重金属在飞灰不同粒径上的分布与粒径有一定的相关性,而半挥发和难挥发性重金属的分布与粒径的相关性不大;中等大小的颗粒对重金属总量的贡献率最大.  相似文献   

9.
微波对垃圾焚烧飞灰重金属稳定影响研究   总被引:1,自引:0,他引:1  
陈玲 《科技信息》2008,(19):59-59
本文探讨了垃圾焚烧飞灰的消解实验,研究了飞灰中重金属的特性,比较了飞灰稳定前后重金属含量的变化,分析了微波影响重金属稳定化测定的因素。  相似文献   

10.
为检验医疗垃圾焚烧飞灰的水泥固化处理效果,对不同飞灰/水泥配比下水泥固化体的凝结时间、抗压强度、重金属浸出毒性等特性方面进行了实验研究.结果表明:掺60%飞灰的水泥固化体终凝时间长达63 h,超出48 h的限值;掺40%飞灰、60%飞灰的水泥固化体7 d的抗压强度仅为0.187 MPa、0.16 MPa,未达到0.2 MPa的要求值;掺40%飞灰、60%飞灰的水泥固化体中Pb的渗沥浓度分别为5.634 mg/L、6.032 mg/L,均超过5 mg/L的限值.根据本实验结果,医疗垃圾焚烧飞灰水泥固化中水泥掺量宜在70%左右,若按照目前国内生活垃圾焚烧飞灰水泥固化工艺的配比(水泥掺量40%以下),各项固化指标均不能达到填埋要求.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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