【作者】 赵志春；

【导师】 杨合；

【作者基本信息】 东北大学 ， 环境科学， 2008， 硕士

【摘要】 转炉渣作为炼钢工艺过程中必然的副产品,其产量随着钢产量的增加大幅攀升,而转炉渣回收利用的方法和能力极其有限。因此,如何有效地综合利用这些转炉渣,对进一步促进我国钢铁工业持续高效地发展具有重要意义。本文利用转炉渣、铁尾矿、粉煤灰为主要原料制备了水泥和免蒸免烧砖建筑材料。采用XRD、显微镜等测试技术对材料的物相组成和显微结构等进行研究。首先,以转炉渣为主要综合利用对象,作为水泥原料和混合材料,采用烧结法制备了硅酸盐水泥,并测定其力学性能,分析了转炉渣作为原料时,对水泥制品性能产生的作用及其作用机理。实验结果表明：①转炉渣作原料时,制备硅酸盐水泥的最优实验方案为：转炉渣3%、铁尾矿3.5%、粉煤灰16%、石灰石77.5%,此时,IM=1.58、KH=0.88、SM=2.11；煅烧工艺为1350℃下保温2h；冷却方式为水淬急冷；石膏的加入量为水泥的3.5%。②转炉渣作混合材料时,当加入6%和10%转炉渣时,并没有使各龄期抗压强度产生明显下降,而当转炉渣掺量由0%增加到15%时,28d抗压强度由73.28Mpa降到47.83Mpa,降幅为34.7%,雷式夹的变化长度由1.5mm增大到3.5mm,凝结时间随转炉渣加入量的增大而延长；虽然转炉渣的加入引起各力学性能的变化,但均符合国家标准,属合格产品。其次,以转炉渣、铁尾矿、粉煤灰为主要原料,制备了新型墙体材料--免蒸免烧砖。采用正交实验考察粉煤灰、石灰、水泥和石膏四种因素对抗压强度影响的主次关系。进一步采用转炉渣替代实验、水泥用量实验确定免蒸免烧砖作结构材料时的配料方案,对免蒸免烧砖的性能进行了测试。研究了成型压力及养护时间等因素对免蒸免烧砖抗压强度的影响,分析了免蒸免烧砖强度的产生机理。实验结果表明：正交实验中,粉煤灰、石灰、水泥、石膏四种因素对抗压强度影响的主次关系为：水泥>石膏>粉煤灰>石灰；转炉渣替代实验可知,当转炉渣替代铁尾矿的百分含量为40%时,免蒸免烧砖的7d和28d抗压强度较高,分别为15.7Mpa,34.9Mpa;减少水泥用量实验可知,当水泥用量减少至2%时,其28d抗压强度为16.8Mpa,已达到MU15,免蒸免烧砖的抗压强度随水泥用量的增加而逐渐增大,最大值到达35.0 Mpa,因此,可以采用不同配料方案制备标号MU15～MU25的免蒸免烧砖；综合考虑个影响因素,当免蒸免烧砖作结构材料时的最优配料方案为：转炉渣26.8%、铁尾矿34.2%、粉煤灰10%、石灰12%、水泥16%、石膏1%；成型压力为20Mpa；测得试样体积密度平均值为1.96×103kg/m3；选用4种不同外加剂：木质素磺酸钙、萘系高效减水剂、氯化钙和硫酸钠,考察其对免蒸免烧砖抗压强度的影响,结果表明萘系高效减水剂免蒸免烧砖的抗压强度提高最为显著,当加入水泥用量1%的萘系高效减水剂时,免蒸免烧砖的7d抗压强度提高率达到了18.7%,28d抗压强度提高率达到6.9%；免蒸免烧砖经过15次冻融循环,平均抗压强度损失率为1.96%,平均质量损失率为0.67%,抗冻性能良好；吸水率平均值为9.7%,表明免蒸免烧砖孔隙率较少,内在质量较好；免蒸免烧砖的抗压强度随着成型压力的增大而增大；随养护时间的延长而增大。更多还原

【Abstract】 Converter slag is the inevitable by-product of steel-making process, the output of converter slag increases with the increment of the steel output. However, the recovery method and technology of converter slag is laggard. Therefore, how to use the converter slag more effectively has important significance in promoting the continuous and efficient development of the iron and steel industry.In this paper, converter slag, iron tailings and fly ash are taken as raw materials for the preparation of cement and steaming-free and burning-free brick. The components and microstructures were examined by element analyzer, X-ray diffraction (XRD) and Microscope.Firstly, converter slag was used as the mainly raw material for the preparation of cement and steaming-free and burning-free brick. The sintered method is adopted to prepare the Portland cement. And the mechanical capabilities are determined. The effect of converter slag as raw material on cement’s capabilities and mechanism is analyzed. The results showed that:①converter slag was used for raw material, the best experimental scheme for preparing Portland cement was converter slag 3%, iron tailings 3.5%, fly ash 16% and limestone 77.5%, respectively; and at this time, IM=1.58、KH=0.88、SM=2.11. Burning craft was at 1350℃keeping 2h; the cooling quomodo was fast cooling in the water. The amount of adding gypsum was 3.5% of cement.②converter slag was used for the additives. The compressive strength of cement at variable ages didn’t go down obviously when adding 6% and 10% converter slag; the compressive strength of cement at 28 day went down from 73.28Mpa to 47.83Mpa when the adding converter slag from 0% to 15%, the extent of decrease was 34.7%. Length change of Le chatelier was from 1.5mm to 3.5mm; the setting time prolonged while adding more converter slag; although adding converter slag led to the change of mechanical capabilities, the product satisfied the standard of GB and belonged to the eligible product.Secondly, The new-style wall material:Steaming-free and burning-free brick making use of converter slag、iron tailings、fly ash as primary material was prepared. The orthogonal experiment is used to determine the successive relationship, such as the effect of fly ash, lime, cement and gypsum on the compressive strength. Then the replacement test of converter slag and experiment of the decreasing cement’s amount to determine the best scheme of steaming-free and burning-free brick are studied. At the same time, the capabilities of steaming-free and burning-free brick are determined. The effect of the molding tension and curing time on the compressive strength of steaming-free and burning-free brick are analyzed, also the mechanism of strength form. The result showed that the effect of fly ash、lime、cement and gypsum on the compressive strength in the orthogonal experiment was:cement> gypsum> fly ash> lime. It showed that the substitute experiment:the compressive strength of steaming-free and burning-free brick was improved as the adding of 40% converter slag in the replacement test of converter slag. Compressive strength was 15.7Mpa and 34.9Mpa, respectively. It showed in the decreasing of cement’s amount in experiment:compressive strength of steaming-free and burning-free brick was 16.8Mpa while the amount of cement decreasing to 2%, already attained MU15. Compressive strength increased with the increment of cement. The highest compressive strength was 35.0 Mpa. Therefore, steaming-free and burning-free brick of MU15-MU25 could be made by using the different scheme; When steaming-free and burning-free brick were used for the structural material, considering all the influencing factors synthetically, the best experimental scheme was that:converter slag 26.8%, iron tailings 34.2%, fly ash 10%, cement 16%, lime 12% and gypsum 1%, respectively; the molding tension was 20Mpa; Average density was 1.96×103 kg/m3. Effects of different additives calcium lignosulfonate, high range water reducing agents, CaCl2, Na2SO4 on compressive strength have been investigated, and its mechanism is analyzed. It showed that the effect of high range water reducer on compressive strength was remarkable. The addition of 1%cement led to the increase of the rate of compressive strength, namely 18.7% for 7 day. The rate of the compressive strength increment was 6.9% for 28 day. Steaming-free and burning-free brick endured 15 freeze-thaw circles. The average losing rate of the compressive strength was 1.96%. The average losing rate of weight was 0.67%. The freeze-proof character is good. The average drink rate was 9.7%. These showed that the porosity is low and the internal quality was well; the compressive strength of steaming-free and burning-free brick increased with the increment of molding tension; and the compressive strength of steaming-free and burning-free brick increased with the increment of curing time.更多还原