利用磷石膏制备建筑材料的研究

发布时间：2018-02-07 11:53

本文关键词： 磷石膏水泥墙体砖加气混凝土自流平砂浆　出处：《西南科技大学》2013年硕士论文　论文类型：学位论文

【摘要】：磷石膏作为一种工业副产物，其大量的排放与堆积已严重污染周边环境，危害到人类的健康。加强磷石膏综合利用的研究受到企业和政府部门的高度重视，是迫在眉睫的大事。本课题从四个方面研究利用磷石膏制备建筑材料：（1）利用磷石膏、硫铁矿烧渣制备高贝利特铁铝酸盐水泥，研究了熟料的煅烧工艺、石膏掺量对水泥性能及水化的影响；（2）直接以未经处理的原状磷石膏为原料制备免蒸压墙体砖，对原料的基本配合比和基本工艺参数进行了研究，并对相关性能进行了检测；（3）直接利用未经处理的原状磷石膏制备免蒸压加气混凝土，以试块的干密度和抗压强度为考核指标，进行了基本原料配比和基本工艺参数的研究，并对制得产品进行相关性能的检测；（4）探索了以未经处理的原状磷石膏为填料制备自流平砂浆的可行性，基于相关性能进行了原料配比的研究，并对相关机理进行了探究。在实验室内，1250℃煅烧60分钟制得了性能优异的高贝利特铁铝酸盐水泥熟料；在熟料中掺加天然石膏能明显地缩短水泥的凝结时间，当天然石膏的掺量在5%~15%时，水泥的终凝时间皆小于25min；天然石膏能促进铁铝酸盐水泥的早期水化，且掺量越高对早期水化的促进作用越明显、总的水化热越低；不同的天然石膏掺量对水泥不同龄期的抗压强度的影响规律不同，当天然石膏掺量为15%时，1天、3天、28天的抗压强度分别为39.3MPa、43.2MPa、53.9MPa；天然石膏掺量对不同龄期水泥膨胀率的影响规律几乎相同，当掺量从0%增加到10%时水泥的膨胀率呈下降的趋势，然而，当天然石膏掺量从10%增加到15%时水泥的膨胀率又有所提高；天然石膏的掺量是铁铝酸盐水泥水化的重要影响因素，它不仅影响水泥的水化产物且影响产物的微观结构。以原状磷石膏为原料制备免蒸压墙体砖，比较了半水石膏、粉煤灰、矿渣对砖性能的影响，得出粉煤灰比半水石膏更有利于提高砖的后期强度和抗冻性；而矿渣与粉煤灰相比，二者的后期强度接近，但掺入矿渣的砖的抗冻性较好。最佳原料配比为：水泥：磷石膏：矿渣：河砂=10:65:10:15，采用20MPa压力压制成型，80℃蒸养8小时后自然养护28天，砖的抗压强度达到35MPa以上，且具有优异的抗冻性和耐水性能。直接利用未经处理的原状磷石膏制备免蒸压加气混凝土砌块，最佳原料配比为：水泥15%，磷石膏55%（干基），矿渣30%，外加生石灰7%、Na2SO41.6%、铝粉0.074%，水料比0.47，最佳发气条件为40℃水温50℃静停发气，最佳养护条件为90℃蒸养24小时；制得试块的干密度686Kg/m3，抗压强度6.3MPa，冻后干质量损失1.5%、抗压强度损失12.7%，导热系数0.15W/(m·K)，以上性能皆能满足标准GB11968-2006《蒸压加气混凝土砌块》对B07级砌块的要求，但干燥收缩值远超出标准的要求，这将是今后研究中的一大挑战。以未经处理的原状磷石膏制备水泥基自流平砂浆具有可行性；当原料配比为：硫铝酸盐水泥12%、硅酸盐水泥8%、磷石膏40%~55%、石英砂（30~50目：40~70目=1:1）25%~40%时能制得满足JC/T985-2005《地面用水泥基自流平砂浆》性能要求的自流平砂浆；通过机理分析认为磷石膏在体系中不仅起到填料的作用，，同时也参与水泥的水化反应。
[Abstract]:Phosphorus gypsum as a by-product, the large number of emissions and accumulated serious pollution of the surrounding environment, harm to human health. To strengthen the research highly valued by enterprises and government departments for comprehensive utilization of phosphogypsum is an imminent event. This topic from four aspects of preparing building materials by using phosphogypsum. (1) the use of phosphogypsum, cinder preparation high Bailey aluminoferrite cement clinker calcining process, studied the effect of gypsum content on the properties of cement and hydration; (2) directly without original phosphogypsum processing as raw material preparation of non autoclaved brick, with the basic of raw materials the ratio is studied and the basic parameters and the related properties were tested; (3) the direct use of untreated ardealite preparation of non autoclaved aerated concrete block, with the dry density and compressive strength test of nuclear index. Study on the basic raw material ratio and basic parameters, and the detection performance of the prepared products were related; (4) to explore without the original phosphogypsum processing feasibility of filler to prepare self leveling mortar, based on the related properties were studied the ratio of raw materials, and the related mechanism was explored.
In the laboratory, 1250 8C 60 minutes with excellent properties of high Bailey aluminoferrite cement clinker; in clinker mixed with natural gypsum can significantly shorten the setting time of cement, when the dosage of natural gypsum in cement 5%~15%, the final setting time is less than 25min; the natural gypsum can promote early water iron aluminate cement, and the higher content of the early hydration effect is more obvious, the lower the total heat of hydration; influence of natural gypsum with different compressive strength of cement at different ages are different, when the natural gypsum content is 15%, 1 days, 3 days compressive. The strength of 28 days were 39.3MPa, 43.2MPa, 53.9MPa; natural gypsum on different age cement expansion rate influence rule is almost the same when the content increased from 0% to 10% when the cement expansion rate decreased, however, when the natural gypsum content increased from 10% to 15% The expansion rate of cement is also increased. The amount of natural gypsum is an important factor affecting the hydration of ferric aluminate cement. It not only affects the hydration products of cement, but also affects the microstructure of products.
Using ardealite as raw materials for the preparation of non autoclaved brick, compared hemihydrated gypsum, fly ash and slag on the performance of the influence that the fly ash brick, than half water gypsum is more conducive to improving the strength and frost resistance of brick; and slag and fly ash compared to two late strength close, but the frost resistance of adding slag brick is better. The best ratio of raw materials: cement: phosphogypsum slag: river sand =10:65:10:15, using 20MPa pressing pressure, 80 degrees of steamed 8 hours after natural curing for 28 days, the compressive strength of brick reached more than 35MPa, and has excellent frost resistance and water resistance.
The direct use of untreated ardealite preparation of non autoclaved aerated concrete block, the best ratio of raw materials: 15% of cement, gypsum 55% (dry base), slag 30%, plus lime 7%, Na2SO41.6%, 0.074% aluminum powder, the ratio of water to material 0.47, the best gas is 40 DEG C temperature 50 DEG C static stop the gas, the optimum curing conditions of 90 DEG C to braise for 24 hours; prepared specimens of the dry density of 686Kg/m3, the compressive strength of 6.3MPa, 1.5% dry mass loss after freezing, the loss of compressive strength of 12.7%, thermal conductivity of 0.15W/ (M - K), the above performance can meet the standard requirements of GB11968-2006< steam gas concrete block > pressure on B07 block, but the drying shrinkage value far beyond the requirements of the standard, it will be a big challenge in the future study.
Without original phosphogypsum cement based self leveling mortar has the feasibility of processing; when the ratio of raw materials: 12% sulphoaluminate cement, Portland cement 8% 40%~55%, phosphorus gypsum, quartz sand (30~50 40~70 =1:1) 25%~40% can be prepared to meet the JC/T985-2005< ground water cement based self leveling mortar on performance requirements self leveling mortar; through the analysis of the mechanism that phosphogypsum in the system not only plays the role of a filler, but also to participate in the hydration reaction of the cement.

【学位授予单位】：西南科技大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU52

【引证文献】