城市生活污水对混凝土的腐蚀及防治研究

发布时间：2018-05-17 14:46

本文选题：污水 + 混凝土　；参考：《石家庄铁道大学》2015年硕士论文

【摘要】：城市污水环境下,大量的处理或输送污水的混凝土构筑物受到了严重的腐蚀,使混凝土的寿命达不到预期的使用年限而发生破坏,其中微生物对混凝土的腐蚀最为严重。在研究混凝土的防腐蚀措施中,混凝土的改性和使用表面涂层都是较为被动的措施,不能从根本上抑制微生物的生成,所以本文中在混凝土中掺加杀菌剂这种较为主动的措施应用在在混凝土的防腐措施中。试验用二沉池的厌氧污泥配制了人工强化污水,模拟微生物对混凝土的加速腐蚀;设计并加工了污水腐蚀混凝土的试验装置;对比着做了污水和清水不同浸泡环境下,掺加不同种类的杀菌剂,分别浸泡在污水中不同的位置,以及不同种类的试件的腐蚀性能和腐蚀机制的研究。与清水浸泡中混凝土试件强度增长的规律不同,污水浸泡环境下,混凝土的抗折强度前28 d是增长的,增长速率达到7.1%,超过28 d后,随着龄期增长,混凝土的强度开始持续下降,到150 d时下降速率达到12.4%。且污水环境下,混凝土试件的抗折强度比抗压强度劣化更明显,抗折强度更能表征试件劣化性能的规律。与强度规律类似,污水浸泡下的混凝土试件质量是持续下降的,到28 d和150 d时,质量损失率分别达到2.24‰和6.73‰;清水浸泡中的试件质量呈现不断上升的趋势,特别是前8周上升趋势比较明显,而后到150 d时上升则逐渐趋于平缓。由此说明浸泡在污水中的试件受到了污水的腐蚀作用。并且对于污水浸泡环境下的全部浸泡、部分浸泡和净浆、砂浆、混凝土试件的对比研究发现:部分浸泡在污水中的混凝土要比全部浸泡在污水中的混凝土性能要好;不同骨料的试件的抗腐蚀性能顺序依次为:净浆砂浆混凝土。一方面是由于厌氧环境下部分浸泡在污水中的试件要比全部浸泡在污水中接触面积小,另一方面是由于骨料引入界面,使材料的耐腐蚀性能变差。污水中浸泡的掺了十二烷基二甲基苄基氯化铵的混凝土试件从初始到整个腐蚀过程中,效果都不太理想,它的抗腐蚀效果甚至不如污水中不掺杀菌剂的试件,因此不适合用作杀菌剂掺在混凝土中。而对于另外两种,掺杀菌剂试件的强度衰减系数和质量损失率均是减小的,掺杀菌剂能减轻污水的腐蚀作用,污水中掺杀菌剂比不掺杀菌剂试件强度能提高17.2%,掺溴化钠的混凝土试件对污水的腐蚀作用有明显的改善,且防腐蚀性能最好;掺钨酸钠的混凝土试件对污水的腐蚀也有防治作用,但是效果不如溴化钠明显,质量能达到掺溴化钠试件的80%左右;掺溴化钠试件越是掺钨酸钠试件体积膨胀率的84.6%。在微观试验中,通过对比清水和污水中浸泡在不同位置的掺杀菌剂和不掺杀菌剂试件的孔结构、XRD和扫描电镜图片发现:污水中、不掺杀菌剂和全部浸泡在污水的环境下CH含量均有所降低;孔隙率和大孔结构数量上增多,污水中水泥石的孔隙率约是清水中孔隙率的1.5倍;污水中不掺杀菌剂水泥石的结构变得疏松,有钙矾石生成,说明掺了杀菌剂可以起到明显的抑制腐蚀的效果。
[Abstract]:In urban sewage environment, a large number of concrete structures to handle or transport sewage have been seriously corroded, causing the life of concrete to be damaged without the expected service life, among which the corrosion of the concrete is the most serious. In the study of concrete corrosion protection, the modification of concrete and the use of the surface coating are all The more passive measures can not fundamentally inhibit the formation of microbes, so in this paper, the more active measures used in concrete are applied in the concrete anticorrosion measures. In this paper, the artificial enhanced sewage was prepared by the anaerobic sludge of two sink, and the accelerated corrosion of the concrete was simulated by the microorganism. The test equipment of sewage corroded concrete is compared with the study of the corrosion performance and corrosion mechanism of different kinds of specimens in different kinds of sewage and different kinds of bactericides in different soaking environment of sewage and water, and the study of corrosion and corrosion mechanism of different kinds of specimens. Under the bubble environment, the first 28 d of flexural strength of concrete is increased and the growth rate is 7.1%. After more than 28 d, as the age increases, the strength of concrete begins to decrease continuously, the decline rate reaches 12.4%. when it reaches 150 D, and the flexural strength of concrete specimen is more obvious than that of anti pressure degree under the environment of sewage. The law of chemical properties is similar to the law of strength. The quality of the concrete specimens soaked in sewage is decreasing continuously. The mass loss rate reaches 2.24 per thousand and 6.73 per 1000 respectively to 28 d and 150 D, and the quality of the specimen in the water immersion is increasing, especially the upward trend in the first 8 weeks, and then gradually rising to 150 D. It shows that the specimens soaked in sewage are subjected to the corrosion of sewage. And for all soaking in the sewage soaking environment, the comparative study of partial soaking and pulp, mortar and concrete specimens found that the concrete soaked in the sewage is better than the concrete in the sewage. The order of corrosion resistance of the specimens is as follows: cement mortar concrete. On the one hand, the parts soaked in the sewage under the anaerobic environment are smaller than all soaked in sewage. On the other hand, the corrosion resistance of the material is worse due to the introduction of the aggregate to the interface. The twelve alkyl two methyl benzyl benzyl is mixed in the sewage. The effect of the concrete specimen of ammonium chloride is not ideal from the initial to the whole corrosion process, and its corrosion resistance is not even better than that of the non sterilizing agent in the sewage. Therefore, it is not suitable to be used as a bactericide in concrete. For the other two, the strength attenuation coefficient and the mass loss rate of the samples are reduced. The addition of fungicides can reduce the corrosion of sewage. The strength of the mixed bactericide in the sewage can be increased by 17.2% than that of the non sterilizing agent. The corrosion effect of the concrete with sodium bromide is obviously improved and the corrosion resistance is the best. The concrete test parts with sodium tungstate can also prevent the corrosion of the sewage, but the effect is not as good as bromination. The mass of sodium can reach about 80% of the sodium bromide test. The more sodium bromide test specimen is 84.6%. doped with sodium tungstate test, the pore structure of the specimen, which is soaked in water and sewage in different positions, is compared, and the XRD and scanning electron microscope pictures show that no sterilizing in sewage is found. In the environment of sewage, the content of CH decreased, the porosity and the number of large pore structure increased, the porosity of the cement stone in the sewage was about 1.5 times that of the clear water, and the structure of the non sterilizing agent in the sewage was loosened and the ettringite was formed. Effect.
【学位授予单位】：石家庄铁道大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X799.3;TU528

【参考文献】