再生粗骨料和矿物掺合料对再生混凝土抗冻性影响的研究

试验研究了不同再生粗骨料取代率对再生混凝土抗冻性的影响,并且以再生粗骨料取代率为100%的再生混凝土作为基准混凝土,分别研究单掺钢渣粉、硅灰以及复掺钢渣粉、硅灰对再生混凝土抗冻性的影响。试验分别从表观特征、质量损失率、相对动弹性模量和抗压强度来分析。试验结果表明:随着钢渣掺量的增多再生混凝土的抗冻性降低;硅灰明显的提高再生混凝土的抗冻性,掺量5%为宜;复掺钢渣和硅灰不同的比例对再生混凝土的抗冻性影响不同,得到复掺硅灰5%+钢渣15%再生混凝土的抗冻性优于基准混凝土。     

Comparison of hydration properties between cement-GGBS-fly ash blended binder and cement-GGBS-steel slag blended binder

The hydration properties of cement-GGBS-fly ash blended binder and cement-GGBS-steel slag blended binder were compared. The experimental results show that the hydration rate of cement-GGBS- steel slag blended binder is higher than that of cement-GGBS-fly ash blended binder within 28 days, but lower than the latter after 28 days. The hydration of cement-GGBS-steel slag blended binder tends to produce more Ca（OH）2 than the hydration of cement-GGBS-fly ash blended binder, especially at late ages. Cement-GGBS- steel slag mortar exhibits higher strength than cement-GGBS-fly ash mortar within 28 days, but at late ages, it exhibits similar compressive strength with eement-GGBS-fly ash mortar and even slightly lower bending strength than cement-GGBS-fly ash mortar. Cement-GGBS-steel slag paste has finer early pore structure but coarser late pore structure than cement-GGBS-fly ash paste. Cement-GGBS-steel slag paste can get satisfied late pore structure and cement-GGBS-steel slag mortar can get satisfied late strength as compared with pure cement paste and pure cement mortar, respectively.     

Synthesis of calcium silicate hydrate based on steel slag with various alkalinities

This study aimed to improve the hydraulic potential properties of the slag. Therefore, a method of dynamic hydrothermal synthesis was applied to synthesize calcium silicate hydrate. The phases and nanostructures were characterized by XRD, FTIR, TEM, and BET nitrogen adsorption. The infl uence of alkalinity of steel slag on its structures and properties was discussed. The experimental results show that, the main product is amorphous calcium silicate hydrate gel with fl occulent or fi brous pattern with a BET specifi c surface area up to 77 m2/g and pore volume of 0.34 mL/g. Compared with low alkalinity steel slag, calcium silicate hydrate synthesized from higher alkalinity steel slag is prone to transform to tobermorite structure.     

抱罐车优化创新设计与应用

针对抱罐车在制造、使用过程中易出现的各种问题,提出相对应的优化设计方法,并予以应用。证明经过创新优化设计后的抱罐车相应性能有了显著提高,指出模块化、智能化、节能、环保、远程监控等将是抱罐车的发展趋势。     

火电厂高温过热器泄漏的原因与预防

高温过热器是锅炉的主要构件之一,高温过热器爆管事故的发生不仅给电厂企业带来安全隐患也会造成较大的经济损失。针对某厂高温过热器在运行中发生爆漏,采用化学成分分析、宏观检验和显微组织分析等方法对爆管进行了分析,查找出了爆管原因。详细介绍了锅炉高温过热器因遗留焊渣而引起的爆管情况,并且从锅炉设备管理、检修等方面,提出了防止过热器爆管的措施,一定采用合格的焊接材料、严格执行正确焊接工艺,才能在实际工作中避免爆管。     

留渣量对“双渣+留渣”炼钢工艺的影响

通过热力学计算以及工业试验研究留渣量对"双渣+留渣"炼钢工艺的影响。理论计算结果表明,在铁水成分维持不变时,其合理的留渣量约为4.3 t,考虑在实际生产中铁水成分的波动,留渣量可取3~5 t。工业试验表明,采用新的"双渣+留渣"炼钢工艺,留渣量过低易造成第1阶段结束倒渣时渣中含Fe量过高,合理的留渣量为3~4 t,平均降低铁损为2~3 kg/t钢。理论计算结果与工艺试验结果基本一致。     

改性钢渣除藻效果研究

对改性钢渣在机械搅拌条件下的除藻效果进行了研究,并分析了改性钢渣预处理与混凝联用工艺对藻类的去除效果和协同作用.实验表明,钢渣经改性后,既能有效地去除水中的藻类,又能降低藻的光合活性,抑制藻的生长;高温活化改性钢渣预处理与混凝联用工艺对藻类有很好的去除效果,其对叶绿素a的平均去除率达91.4％,远高于单纯的钢渣预处理和混凝工艺.这暗示了两者之间在除藻方面存在协同作用.     

小型转炉溅渣护炉实践

马钢第二钢轧总厂炼钢分厂通过分析影响溅渣护炉操作的几个重要因素,通过优化终渣调整和溅渣枪位等措施,提高溅渣护炉应用效果,降低耐材消耗,增强了生产的平稳性,取得了显著的经济效益。     

Valorization of Al slag in the production of green ceramic tiles: Effect of experimental conditions on microstructure and crystalline phase composition

This work reports the results of an investigation aimed at the development of sintered glass-ceramic tiles by the sinter-crystallization of mixtures composed of aluminum slag and reclaimed packaging glass. The thermal behaviors of mixtures incorporating 50 and 60 wt% Al slag were established by differential thermal analysis (DTA). Green compacts were sintered in a temperature range of 800°C-1050°C and then soaked for 10-60 minutes. The mineralogical characterizations of the sintered materials were obtained by X-ray diffraction (XRD). The achieved results indicated that the sintering of aluminum slag and packaging glass reclaimed led to a glass-ceramic material composed mainly of needle-like crystals of wollastonite (CaSiO₃). The bloating of samples during firing was evaluated according to a Cougny predictive diagram. After initial observations and according to bending strength characterizations, sintered tiles prepared from aluminum slag and glassy sand are appropriate for floor pavement and wall covering.     

高韧性自保护药芯焊丝

采用正交设计方法，研制出一种新氟钙钛渣系（ＣａＦ２－ＴｉＯ２－ＭｇＯ）的自保护药芯焊丝，其焊接工艺性能良好，烟雾少，并且熔敷金属组织均匀，细小，塑性和低温韧性高，是与５５０ＭＰａ级低合金高强钢相匹配的一种高效焊接材料，适于野外焊接重要结构。