摘 要

循环流化床燃煤固硫技术是为了适应环境保护的要求而发展起来的先进燃煤技术，具有燃料适应性广，燃烧效率和脱硫效率高等优点。在循环流化床锅炉煅烧后排出的固体废弃物即为CFB灰渣。但由于循环流化床锅炉排放的灰渣与普通锅炉不同，灰渣的处理利用技术并不成熟，大量灰渣这阻碍了循环流化床燃煤技术的进一步推广和发展。本文以CFB灰渣为主要原料，以轻质陶粒为粗骨料进行轻质隔墙板的制备技术和应用技术研究。本课题首先测试了灰渣的物理化学特性，研究了其作为集料的可行性；然后设计若干组实验，以不同掺量的灰，和作为细骨料替代天然砂的炉渣，配制水泥砂浆，进行砂浆实验。根据实验结果，选出性能最优的一组配合比，作为陶粒混凝土配合比的设计基础。以不同掺量的陶粒和炉渣作骨料配制陶粒混凝土，测试陶粒混凝土的容重，强度等性能，研究不同陶粒掺量对混凝土性能的影响，实验证实了CFB灰渣作为集料的可行性，配制出了符合设计强度LC20的陶粒混凝土；CFB灰渣掺入水泥砂浆中时，高灰掺量会使水泥砂浆强度增大，最高的一组28d强度值为31.8MPa；随着陶粒的增加，混凝土试块的容重减小，最小的一组干容重为1211kg/m³;抗压强度表现为先增强后降低，当陶粒掺量在33%-50%时，混凝土强度最大，28d强度最大值为25.94MPa。

关键词：CFB灰渣；陶粒；粗细集料；强度等级；影响分析

Abstract

Circulating fluidized bed coal burning and sulfur fixation technology is an advanced coal burning technology developed to meet the requirements of environmental protection. It has the advantages of wide adaptability of fuel, high combustion efficiency and desulfurization efficiency.The solid waste discharged after calcining in CFB boiler is CFB ash.However, due to the difference between the ash discharged from CFB boilers and ordinary boilers, the treatment and utilization technology of ash residue is not mature and a large amount of ash residue  is produced which hinders the further popularization and development of CFB coal burning technology.In this paper, CFB ash is used as the main raw material and light ceramsite as coarse aggregate to study the preparation technology and application technology of light partition board.Firstly, the physical and chemical properties of ash and slag are tested, and the feasibility of ash and slag as aggregate is studied.Then, a number of experiments were designed, in which different amounts of ash and slag that were used as fine aggregate to replace natural sand, and cement mortar was used for mortar experiments.According to the experimental results, a set of mixture ratio with the best performance was selected as the design basis of the mixture ratio of ceramsite concrete.Ceramsite concrete was prepared with different contents of ceramsite and slag as aggregate, the bulk density, strength and other properties of ceramsite concrete were tested to study the influence of different contents of ceramsite on the performance of concrete.The feasibility of using CFB ash as aggregate was proved by experiment.When CFB ash and slag are added into cement mortar, high ash content will increase the strength of cement mortar,the highest group of 28d intensity value was 31.8MPa;With the increase of ceramsite, the bulk density of concrete specimen decreases,the smallest group has a dry bulk density of 1211kg/m³, and the compressive strength first increases and then decreases. When the content of ceramsite is between 33% and 50%,the strength of ceramsite concrete is the highest,the maximum strength at 28d was 25.94.

Keywords: CFB ash;Ceramsite.Coarse and fine aggregate;Strength grade;The impact analysis

目 录

第1章 绪论 1

1.1 研究的背景和研究的意义 1

1.1.1 CFB灰渣 1

1.1.2 CFB灰渣的特征 1

1.1.3 陶粒混凝土 2

1.1.4 陶粒混凝土的特性 2

1.1.5 研究的意义 3

1.2 国内外的研究现状 4

1.2.1 国内外CFB灰渣的研究现状 4

1.2.2 陶粒在混凝土中应用的国内外现状 5

1.3 研究目标、内容和技术方案 5

1.3.1 研究目标 6

1.3.2 研究内容 6

1.3.3 技术路线 6

2.1 实验原材料 8

2.1.1 水泥 8

2.1.2 CFB灰 8

2.1.3 炉渣 9

2.1.4 陶粒 9

2.1.5 外加剂 10

2.2 试验方法 10

2.2.1 微观性能测试 10

2.2.2 集料性能测试 10

2.2.3 试件制作与养护 12

2.2.4 砂浆试件的强度测试 12

2.2.5 混凝土试件的性能测试 12

3.1 陶粒性能研究 13

3.1.1 堆积密度 13

3.1.2 筒压强度 13

3.1.3 吸水率 13

3.2 CFB灰渣性能研究 14

3.2.1 炉渣的细度模数及颗粒级配 14

3.2.2 炉渣的表观密度、松堆密度和孔隙率 15

3.2.3 炉渣的吸水率 15

3.2.4 炉渣的压碎指标 15

3.2.5 CFB灰渣的矿物组成 16

第4章 陶粒对CFB灰渣混凝土性能影响的研究 17

4.1 CFB灰渣配制水泥砂浆 17

4.1.1 原材料 17

4.1.2 设计配合比，制备水泥砂浆 17

4.1.3 炉渣和CFB灰的不同掺量对水泥砂浆的性能影响 17

4.2 不同陶粒掺量混凝土的制备 18

4.2.1 配合比设计 19

4.3 陶粒掺量对混凝土性能的影响 19

第5章 结论与展望 23

参考文献 24

致谢 26

第1章 绪论

1.1 研究的背景和研究的意义

1.1.1 CFB灰渣

我国现阶段的主要能源是煤炭，这一格局在很长时间内不会有太大变化。我国煤炭的利用以燃烧为主。煤炭燃烧过程中，除了会产生大量灰渣，还会产生SO₂、NO_X等一系列大气污染物，造成酸雨等环境危害。流化床燃煤固硫技术（CFBC）是先进、高效、清洁，为了环境保护而发展起来的燃煤固硫技术，在循环流化床锅炉内，含硫煤与脱硫剂按一定比例煅烧后排出的固体废物即为CFB灰渣，目前由于对灰渣的基本特性研究不足，使得灰渣的综合利用率较低，大部分只能采用堆积或填埋的方式处理^[1]。

1.1.2 CFB灰渣的特征

固硫灰渣从外形上观察，可分为固硫灰和固硫渣，固硫灰从循环流化床锅炉的烟道收集，固硫渣从炉底排出，根据不同地区，不同厂家的原煤品质，固硫剂种类，燃烧方式，燃烧温度等的不同，固硫灰和固硫渣的比例也随之变化。

(1)细度及粒径