Zeolitic Tuffs as Raw Materials for Lightweight Aggregates
Zeolitic Tuffs as Raw Materials for Lightweight Aggregates
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DOI：
10.4028/www.scientific.net/kem.264-268.1431
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发表时间：
2004-04
期刊：
影响因子：
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通讯作者：
M. Dondi;P. Cappelletti;G. Cerri;M. Gennaro;R. Gennaro;A. Langella
中科院分区：
文献类型：
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作者：
M. Dondi;P. Cappelletti;G. Cerri;M. Gennaro;R. Gennaro;A. Langella
摘要本研究的目的是评估意大利沸石岩用于生产轻质骨料的可能性。特别是，在高温下的膨胀和烧结产品的工艺特性进行了研究。考虑了来自北方撒丁岛的15个含沸石火山碎屑岩和来自坎帕尼亚和托斯卡纳的3个沸石化凝灰岩（索拉诺和坎帕尼亚熔结凝灰岩以及那不勒斯黄色凝灰岩）。结果表明，烧成膨胀主要取决于原料的化学成分（特别是SiO2和助熔氧化物，如Fe 2 O3、Na 2 O、K2 O、MgO和CaO）和含水量（主要与沸石用量有关）。其他相关参数为最大膨胀温度（范围为1350 - 1500 °C，无添加剂）和浸泡时间（2 - 5分钟）。有些产品是高度不透水的（吸水率低于1%），并表现出相当大的燃烧膨胀（>100%的体积），低堆积密度（0.5-0.7 g·cm-3）和公平的技术性能（松散重量和颗粒强度）。这些令人鼓舞的结果使一些调查凝灰岩有趣的原料生产轻骨料。
Abstract The aim of this research is to assess the possible use of Italian zeolitic rocks for the production of lightweight aggregates. In particular, both the expansion at high temperature and the technological features of fired products were investigated. Fifteen zeolite-bearing volcanoclastites from Northern Sardinia and three zeolitized tuffs from Campania and Tuscany (Sorano and Campanian ignimbrites and Neapolitan Yellow Tuff) were taken into account. The firing expansion turned out to be mainly dependent on the chemical composition (especially SiO 2 and fluxing oxides such as Fe 2 O 3 , Na 2 O, K 2 O, MgO and CaO) and the water content (largely related to the zeolite amount) of the raw materials. Other relevant parameters were the temperature of maximum expansion (ranging between 1350 and 1500 °C, without additives) and soaking time (between 2 and 5 min). Some products are highly impervious to water (water absorption below 1%) and exhibit a considerable firing expansion (>100% in volume), a low bulk density (0.5–0.7 g·cm −3 ) and fair technical properties (loose weight and strength of particles). These encouraging results make some of the investigated tuffs interesting raw materials for the production of lightweight aggregates.