地聚物对固化焚烧飞灰的研究

垃圾焚烧处理技术产生的飞灰浓缩了重金属等一些高毒性当量的危险成分, 如果处理不当会 产生二次污染, 因此焚烧飞灰被认为是危险废物, 必须进行特殊处理.论文对地聚物固化垃圾焚烧 飞灰的工艺及养护条件进行了实验研究, 以抗压强度和重金属浸出质量浓度为效果表征量, 研究了 地聚物固化飞灰的合成配方.结果表明:氧化物配比为m(Na2O)∶m(SiO2)=0 .30 , m(SiO2)∶m (Al2O3)=4 .7 时, 飞灰掺量为40 %的固化体在养护7 天后抗压强度能达到31 .25 MPa , 固化体中 Pb , Zn ,Cu 和Cr 的浸出质量浓度分别达到0 .183 8 , 0 .023 1 , 0 .008 1 , 0 .367 9 mg/L .     

地聚物固化体抗高温性能及数学模型研究

地聚物对焚烧飞灰中的重金属具有良好的固定作用.为了进一步探索固化飞灰后的地聚物固 化体的抗环境侵蚀性能, 开展了固化体高温—恒温时间—地聚物抗压强度的研究及经受高温后固 化体的重金属浸出试验, 探讨抗压强度与高温、恒温时间之间的关系以及地聚物固化垃圾焚烧飞灰 的稳定性.通过对固化体试块的高温试验以及对不同温度、不同恒温时间下固化体抗压强度试验, 分析这三者之间的关系, 建立数学模型, 并根据实验结果拟合温度—恒温时间—抗压强度的三维 曲面.     

水泥对铬渣无害化处理及其固化体浸出毒性的研究

对水泥作胶凝材料固化铬渣进行了研究。首先硫酸亚铁溶液与铬渣搅拌，然后再加入粉煤灰，水泥，矿渣等，部分还原的六谷铬转换为三价铬被固定在水泥基质中。研究结果表明，这样得到的固化体六价铬浸出毒性低于国家标准，抗压强度可达30MPa以上，能用于建材。本实验还考虑日晒，浸出时间和固化体粒度等因素对固化体浸出毒性的影响。     

利用热等离子体熔融垃圾焚烧飞灰

为了评价垃圾焚烧飞灰的热等离子体熔融处理效果, 研究SiO2和CaO对重金属固化效果和重金属毒性浸出特性的影响. 在飞灰中添加一定比例的SiO2和CaO, 配置成不同的配灰样品, 利用纯氩热等离子体在1 400～1 500 ℃下, 对飞灰及配灰进行熔融玻璃化的实验研究, 分别利用X射线能量色散谱仪(EDX)、场发射扫描电子显微镜(FSEM)、X射线衍射仪(XRD)和毒性浸出方法(TCLP)分析飞灰和熔渣的化学组成、微观结构、晶相组成和重金属毒性浸出特性. 结果表明, 热等离子体熔融所得熔渣为无定形的玻璃体, 重金属浸出质量浓度均远低于毒性标准. SiO2和CaO的添加都可以改善重金属固化效果, CaO比SiO2对Cu、Zn、Cd和Pb挥发的抑制效果更好. SiO2的添加可以改善熔渣中重金属的浸出特性, 而CaO的作用与之相反.     

城市生活垃圾焚烧飞灰中重金属的固化/稳定化处理

城市生活垃圾焚烧飞灰已被明确规定为危险废物,其中含有的大量有毒重金属对自然环境和人类生存会造成严重危害.综述了目前常用的水泥固化、烧结固化、熔融固化、药剂稳定化四种固化/稳定化垃圾焚烧飞灰中有毒重金属的方法,对比分析了各项技术的优缺点;对城市生活垃圾焚烧飞灰中重金属固化/稳定化处理的发展前景进行了展望,指出资源化利用是未来发展的必然趋势.     

掺加矿渣的土壤聚合物对重金属的固化

在土壤聚合物固化重金属时进行了掺加不同量高炉矿渣的实验，测定固化体的抗压强度、浸出毒性．试验结果表明，土壤聚合物掺加一定量的高炉矿渣固化重金属对不同的重金属固化效果不同，但总体来说，固化体的浸出毒性低于国家标准，抗压强度可迭30MPa以上，能用于建材．高炉矿渣的掺量在30％左右时抗压强度最好，浸出毒性则随着高炉矿渣掺量的增加而下降，所以利用土壤聚合物固化一定含量的重金属时，可以加入适当的高炉矿渣来减小浸出毒性．     

茶皂素稳定和改性处理垃圾焚烧飞灰试验研究

以上海市生活垃圾焚烧飞灰的高附加值资源化和稳定化为目标,初步研究茶皂素对城市生活垃圾焚烧飞灰改性活化以及对重金属离子的螯合效果,改性飞灰的活化指数可达95%以上.在试验的同时,比较了茶皂素、EDTA,硫脲和磷酸钠对飞灰中重金属的稳定螯合效果.经重金属毒性浸出试验表明,茶皂素对飞灰中的重金属具有较强的束缚能力,其稳定化效果与硫脲和磷酸钠螯合剂能力相当.     

垃圾焚烧飞灰制作碱激发砖的环境安全性评估

为探索垃圾焚烧飞灰的资源化利用,使用流化床焚烧炉产出的焚烧飞灰、燃煤飞灰及矿渣粉为主要原料,由氢氧化钠及硅酸钠调制为碱激发剂制备碱激发砖材.当焚烧飞灰最大添加比为40%时,其28 d的抗压强度达28.69 MPa,符合混凝土实心砖规范(GB/T21144—2007)要求.环境兼容性方面,28 d的垃圾焚烧飞灰碱激发砖材HJ/T 300浸出测试结果显示,重金属稳定于砖材中.长期pH相关联性浸出试验发现,砖材中重金属Ba的浸出量随pH的降低而增加;重金属Zn在pH小于7的环境下可检测到有浸出,而重金属Cd、Cr、Cu、Ni、Pb只有在pH为6以下的环境才会有浸出现象.桶槽扩散浸出试验结果显示,焚烧飞灰碱激发砖材环境稳定pH在11.0~11.5,且仅有微量重金属钡（Ba）及铬（Cr）出现释出现象,分析显示其浸出量为微量.     

碱矿渣水泥基铬渣固化体浸出毒性的安全性研究

对碱矿渣水泥基铬渣固化体侵出毒性的安全性进行了研究,结果表明,即使固化体在破坏的情况下,其浸出毒性仍在安全剂量范围内,固化体的早期表面浸出率为１０＾－３￣１０＾－４数量级,后期表面浸出率仅为１０＾－６数量级,与玻璃固化体的浸出率相当,可见固化体的长期抗表面浸出能力是很强的,完全可以用作建筑材料。     

脲酶菌的筛选及其对垃圾焚烧飞灰的固化

焚烧是当前城市垃圾处置的重要方式,焚烧飞灰及其重金属却是威胁周围环境的一种污染源。为降低这种污染,从植物根际筛选获得高活性脲酶菌,并比较脲酶菌固化焚烧飞灰后的抗压强度、颗粒级配及重金属稳定化效果。结果表明:从丹参根际土壤内分离获得2株高效脲酶菌Bacillus aryabhattai UR-F51和Pseudomonas taiwanensis UR-121;将脲酶菌与飞灰按一定比例混合后固化,菌株UR-F51和UR-121使固化飞灰的抗压强度分别增加48.00%和27.00%,固化颗粒粒径增加10.00%～145.00%;飞灰中重金属(Cr、Ni、Cu、Cd、Hg和Pb)的固化率分别为15.27%～37.23%、41.49%～90.43%、37.17%～99.73%、42.86%～71.42%、20.00%～40.00%和47.06%～82.35%。脲酶菌可显著提升飞灰及其重金属的固化效果,菌株UR-F51的固化效果最好,为缓解城市生活垃圾焚烧飞灰污染提供一种新途径。     

The Cement Solidification of Municipal Solid Waste Incineration Fly Ash

The chemical composition, the content and the leachability of heavy metals in municipal solid waste incineration （ MSWI） fly ash were tested and analyzed. It is shown that the leachability of Pb and Cr exceeds the leaching toxicity standard, and so the MSWI fly ash is considered as hazardous waste and must be solidifled. The effect of solidifying the MSWI fly ash by cement was studied, and it is indicated that the heavy metals can be well immobilized if the mass fraction of the fly ash is appropriate. The heavy metals were immobilized within cement hydration products through either physical fixation, substhtaion, deposition or adsorption mechanisms.     

Solidification of Municipal Solid Waste Incineration Fly Ash with Cement and Its Leaching Behaviors of Heavy Metals

The solidifying qffect of cement addition on municipal solid waste incineration fly ash ( MSWFA for short, collected from the gas exhaust system of MSW incinerator), the interaction of MSWFA with cement and water and the leaching of heavy metals from cement-solidified MSWFA are investigated. The main results show that : ( 1 ) when MSWFA is mixed with cement and water, 112 evolution, the formation and volume expansion of AFt will take place, the volume expansion can be reduced by ground rice husk ash addition ; (2) heavy metals do leach from cement-solidified MSWFA and at lower pH more leaching will occur; (3) compared with cement - so-lidified fly ash, the leachate of solidified MSWFA is with higher heavy metal contents ; (4) with the increment of cement addition leached heavy metals are decreased ; and (5) concentrations of Zn , Mn , Cu and Cd in all the leachates can meet the relevant Standards of Japan, but as the regulations for soil and groundwater protection of Japan are concerned, precautions against the leaching of Pb , Cl^- and Cr^6 and so on are needed.     

Effect of MSWI fly ash and incineration residues on cement performances

The activities of municipal solid waste incineration (MSWI) fly ash and incineration residues were studied contrastively, through the component analysis and the activity ratio tests. The mechanical properties, hydration mechanism and leaching toxicity of the hardened cement paste mixing with MSWI fly ash and incineration residues were investigated. The experimental results indicated that the active constituents (CaO+Al₂O₃+Fe₂O₃) in MSWI fly ash were higher than those in incineration residues. Therefore the activity ratio of MSWI fly ash was 43.58%, twice as much as that of incineration residues. Meanwhile, the hydration of cement was delayed by mixing with MSWI fly ash and incineration residues, which also reduced the cement strength markedly. By adding with exceeding 20% MSWI fly ash, the specimens expanded and microcracks appeared. The leaching toxicities of cement pasted mixed with MSWI fly ash and incineration residues were lower than the Chinese national standard. Accordingly the cement mixed by MSWI fly ash and incineration residues can be considered as the environment-friendly materials.     

混合材对MSWI制CSA水泥性能的影响

以城市垃圾焚烧飞灰（MSWI）为主要原料,在实验室成功烧制了硫铝酸钙（CSA）水泥熟料.研究了单掺或复掺不同种类、不同掺量的混合材后,CSA水泥的力学性能和水化性能.结果表明：石灰石粉（LI）/矿渣粉（SL）在CSA水泥中较为适用,而粉煤灰（FA）/MSWI的活性较差;单掺4种混合材均对CSA水泥早期强度产生不利影响;单掺LI/SL对后期强度发展有益;复掺混合材较单掺效果好,尤其是试样10％LI＋10％SL、10％LI＋10％MSWI和5％LI＋15 ％SL.     

C40玻璃自密实再生混凝土配合比的设计研究

为研究废弃玻璃与粉煤灰在自密实再生混凝土中的最佳取代率,在再生粗骨料取代率为20%的基础上,利用废弃玻璃取代天然细骨料(比例分别为0%、10%、20%、30%),同时等梯度增加粉煤灰取代水泥的比例(分别为20%、30%、40%).通过测定混凝土坍落扩展度判定混凝土的流动性,并测定混凝土的7、14、28、56 d抗压强度.试验结果表明,当废弃玻璃与粉煤灰的最佳取代率分别为20%和30%时,自密实再生混凝土的力学性能和经济性达到最佳.     

磷酸盐水泥对137Cs的固化性能

以含95％MgO的重烧镁砂、磷酸盐和硼砂为原料,制备了磷酸盐水泥,研究其对137Cs的固化性能。通过XRD衍射分析、SEM电镜扫描等手段对固化体物相组成及显微结构进行分析,参照国家标准“放射性废物固化体长期浸出试验”（GB7023—86）对固化体进行抗浸出性能试验。结果表明,当以磷酸氢二铵为原料时,137Cs的加入会降低磷酸盐水泥固化体的抗压强度,137Cs的含量越多,强度损失越小;当以磷酸二氢铵为原料时,随着137Cs的加入,强度先减小后增大,掺量为1．6％时强度甚至超过了空白体系;以磷酸二氢钾为原料时,137Cs的加入会使强度减小,减小程度和掺量关系的规律性不明显。以磷酸二氢铵、磷酸二氢钾为原料的固化体抗压强度明显优于以磷酸氢二铵为原料的固化体。以磷酸二氢铵为原料的固化体,137Cs的42d浸出率和累计浸出分数低至2．1×10-4（em·d11）和7．74×10^-3cm,强度值和浸出率均优于国家标准相关要求,表明了磷酸盐水泥对137Cs有良好的固化效果。     

化学固化对淤泥颗粒粒径及含水率影响的试验研究

以水泥、石灰和粉煤灰为固化材料,按照正交方法设计配合比,进行了淤泥的固化试验,通过测试固化淤泥的颗粒级配及含水率,研究了淤泥固化后其颗粒粒径分布及含水率的变化,探讨了固化材料中的各组分对淤泥固化效果的影响。结果发现,粉煤灰最有利于淤泥内部自由水和吸附水的减少,而石灰对于增大粒径效果最明显。淤泥经化学固化后,粘粒含量从34%降低到1%以下,强度稳定性和耐水性大大提高。     

活性MgO固化淤泥水稳特性试验研究

将绿色、低碳、环保的活性MgO引入淤泥固化处理,通过对比活性MgO、MgO-粉煤灰及传统固化剂水泥固化淤泥试样,分析不同浸水时间下试样外观、质量、应力-应变关系和无侧限抗压强度等性质,综合评价活性MgO基材料固化淤泥的水稳特性.结果表明：活性MgO固化淤泥水稳性显著优于未固化淤泥,且水稳性随掺入MgO质量分数和标准养护龄期的增加而增强;粉煤灰的加入可以显著改善活性MgO固化淤泥的抗压强度和水稳性;浸水时间增加对固化淤泥无侧限抗压强度呈削弱效应,提高掺入活性MgO质量分数可以减小固化淤泥破坏应变;整体上,活性MgO-粉煤灰固化淤泥水稳性优于活性MgO,活性MgO优于传统固化剂水泥.微观分析表明：Mg（OH）₂和水化硅酸镁M-S-H等胶结物质是活性MgO和活性MgO-粉煤灰固化淤泥水稳性增强的最主要原因.     

Experimental research on inorganic solidified foam for sealing air leakage in coal mines

In order to efficiently seal air leakages and control spontaneous combustion of coal, solidified foam was developed by adding a certain compound additive to fly coal ash and cement as the main materials. It was prepared basing on the foaming characteristic through physical and mechanical system. We studied the effects of the different types of foaming agents, the mass ratio of cement to fly ash, and the mass ratio of solid to water and content of cellulose on the performance of solidified foam. The results show that when adding the composite protein, surfactant and cellulose foaming agents. The cement-fly ash ratio of 0.75:1, the water solid ratio as large as 2:1, and the solidified foam with high properties and density of only 516 kg/m³ and compressive strength of up to 12.68 MPa were prepared. But the initial setting time, identity and compressive strength may be changed by varying the water solid ratio and/or the additives. We theoretically analyzed the influence mechanism of foam density, compressive strength and water solid ratio. The solidified foam is especially suitable for sealing surface leakage channels and filling the goaf with a wide application prospects.     

Effect of MSWI Fly Ash and Incineration Residues on Cement Performances

The activities of municipal solid waste incineration (MSWI) fly ash and incineration residues were studied contrastively, through the component analysis and the activity ratio tests. The mechanical properties, hydration mechanism and leaching toxicity of the hardened cement paste mixing with MSWI fly ash and incineration residues were investigated. The experimental results indicated that the active constituents (CaO+Al2O3+Fe2O3) in MSWI fly ash were higher than those in incineration residues. Therefore the ...