疏浚底泥免烧陶粒的裹壳改性及其应用于建材的研究

发布时间：2018-05-22 20:29

本文选题：疏浚底泥 + 免烧陶粒　；参考：《天津科技大学》2017年硕士论文

【摘要】：随着我国工业化进程以及疏浚量逐年增加,产生大量占地面积大、含水率高、组成成分复杂、容易产生二次污染的疏浚底泥。因此,探索疏浚底泥废资源化利用的新途径显得尤为重要。本文研究致力于探索研究将疏浚底泥制备免烧砖,不仅能有效解决疏浚底泥处理难题,开发新型建筑材料,符合国家政策导向,同时可以节能利废,保护我国土地资源,应用前景广泛。目前,利用疏浚底泥制备免烧砖尚无工业化报道,研究工作大多是将底泥与水泥等材料直接混合压制成砖。直接掺入法制备的免烧砖存在强度低、耐水性能差、抗冻融性能差等一系列问题,基本无实际应用价值。针对此问题,本文提出将疏浚底泥制备免烧陶粒,再与胶凝材料混合、压制成免烧砖的新工艺,解决了底泥与胶凝材料的相容性问题。并针对疏浚底泥陶粒强度低、抗冻融性较差等问题,系统探讨了陶粒的裹壳改性工艺,有效改善了陶粒各项性能。具体研究工作如下:陶粒裹壳改性的研究结果:(1)疏浚底泥免烧陶粒经裹壳改性后,所制备的裹壳陶粒壳、核层结合紧密,能够大幅提高疏浚底泥免烧陶粒的强度,性能应符合GBT17431.1-2010《轻集料及其试验方法》的标准要求;(2)粒径分析:改性陶粒,大部分粒径集中在3-8mm,8#和9#主要集中在5-8mm; (3)强度分析:添加助剂B的五组陶粒15#-19#平均单颗强度相对更高,但单个来看,裹壳时间最长的5#裹壳陶粒的强度相对于其他组最高,达到2.47MPa,壳层最厚的9#强度达到1.99MPa; (4)抗冻性分析:9#陶粒的质量损失率最低,21次冻融循环之后的损失率1.99%,添加助剂B,总体抗冻效果非常明显。改性裹壳陶粒水泥试件的研究结果:(1)密度:相比于20#烧结陶粒水泥试件,所有试件密度都小于2.0g/cm3,满足轻质的基本要求。(2)吸水率:所有陶粒试件的吸水率小于7%。添加助剂B的组,整体吸水率较低,19#陶粒水泥试件的吸水率最低是4.38%。(3)抗冻性:3#、4#、5#水泥试件的抗冻性能良好,尤其是裹壳时间最长的5#,21次后冻融损失率仅为7.42%。壳层最厚的9#,21次后冻融损失率仅为2.04%。从15#到17#,随着助剂B用量的增加,试件的抗冻性效果在逐渐变强。尤其17#性能最优,21次后质量损失率仅为11.22%。底泥陶粒制备免烧砖的研究结果表明:(1)强度:裹壳陶粒砖单块测试强度大于12Mpa,达到Mu15的标准;防水陶粒砖单块测试强度大于8Mpa,达到Mu10的标准。(2)抗冻性:陶粒砖经历25次冻融后,质量损失率小于5%,满足使用。(3)整体防水陶粒和裹壳陶粒的制备工艺,可大幅度提高陶粒的强度、耐水性、抗冻融性,可作为建材基本原料。
[Abstract]:With the development of industrialization and the increase of dredging quantity in China, a large amount of dredged sediment with large area, high moisture content, complex composition and easy to produce secondary pollution is produced. Therefore, it is very important to explore a new way to utilize dredged sediment waste. This paper is devoted to exploring and researching the preparation of unburned brick from dredged sediment, which can not only effectively solve the problem of dredging sediment treatment, develop new building materials, conform to the guidance of national policy, but also save energy and waste, and protect our land resources. The application prospect is wide. At present, there is no industrial report on the use of dredged sediment to prepare sintered brick. Most of the research work is to directly mix sediment and cement into brick. A series of problems, such as low strength, poor water resistance and poor freezing and thawing resistance, are existed in the sintered bricks prepared by direct blending method, which have no practical application value. In order to solve this problem, a new process of preparing sinus-free ceramsite from dredged sediment and mixing it with cementitious material is put forward in this paper, and the compatibility between sediment and cementing material is solved. Aiming at the problems of low strength and poor freeze-thaw resistance of ceramsite in dredged sediment, the shell modification technology of ceramsite is discussed systematically, which can effectively improve the properties of ceramsite. The specific research work is as follows: the results of the study on the modification of ceramic pellets wrapped in shell are as follows: (1) when the dredged sediment is modified by unburned ceramsite, the core-bound ceramic shell can be prepared, which can greatly improve the strength of the dredged sediment without firing. The properties should meet the standard requirement of GBT17431.1-2010 "Light aggregate and its Test method".) Particle size analysis: modified ceramsite, most of which are concentrated in 3-8 mm ~ (8#) and 9# mainly in 5-8 mm; ~ (3) strength analysis: the average strength of 15 #-19 # of five groups of ceramsite added with additive B is higher than that of "15#-19#", But on a single point of view, the longest shell wrapped ceramsite had the highest strength compared to the other groups. When the shell thickness reached 2.47 MPA, the thickest shell strength reached 1.99 MPA; (4) Frost resistance analysis showed that the weight loss rate of the 20 ~ (-4)% ceramsite was the lowest after 21 freeze-thaw cycles, and the loss rate was 1.99% after 21 freeze-thaw cycles, and the total antifreeze effect was very obvious when additive B was added. Density: compared with 20 # sintered ceramsite cement specimen, the density of all samples is less than 2.0 g / cm ~ 3, which meets the basic requirement of light weight. The water absorption rate of all samples is less than 7%. In the group of additive B, the whole water absorption rate of 19 # ceramsite cement specimens was 4.38% and 4.38% respectively.) the freezing resistance of the concrete specimens was good, especially the freeze-thaw loss rate of the longest crusting time was 7.42% after 21 times. The loss rate of freezing and thawing of the thickest shell was 2.04% after 21 times. From 15# to 17#, with the increase of the dosage of additive B, the frost resistance of the specimen increased gradually. In particular, the mass loss rate of 17 # is only 11.22 after 21 times. The results of the study on the preparation of unburned brick with ceramic pellets from bottom mud show that the strength of ceramic brick with shell is more than 12Mpa. which is up to the standard of Mu15, and the test strength of waterproof ceramic brick is more than 8Mpa.which meets the standard of Mu10: the strength of ceramic brick has been frozen and thawed for 25 times. The quality loss rate is less than 5. It can be used as the basic raw material for building materials, which can greatly improve the strength, water resistance and freeze-thaw resistance of ceramsite.
【学位授予单位】：天津科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ174.76

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