不锈钢污泥与碱共存条件对水泥熟料烧成的影响

采用不锈钢冷轧脱水污泥参与高碱生料的配料,并通过正交试验研究污泥掺量、烧成温度、碱含量等因素对熟料烧成质量的影响。结果表明其影响顺序为:污泥掺量>烧成温度>碱含量。分析认为,这是因为污泥中既含有较多活性较高的CaO和Fe2O3,同时其中还有具有良好矿化作用的F,Cr,Ni等微量元素;当高碱生料中适量配入不锈钢污泥并与适宜的烧成温度相结合,能显著改善熟料矿物的形成条件,从而有效抑制碱的危害,提高熟料的质量。

水泥碱含量对碱-骨料反应影响的试验研究

基于不同规程标准中的砂浆棒快速法,开展水泥碱含量及超量液相碱含量对骨料碱活性试验的影响研究,采用3种不同碱含量的水泥分别与非活性骨料、疑似活性骨料以及活性骨料进行骨料碱活性试验,采用3个等级的超量液相碱含量对非活性骨料、疑似活性骨料进行骨料碱活性试验,分析了碱含量对不同骨料的快速碱-硅酸反应影响规律。结果表明:碱含量不超过1.0%时,水泥碱含量对骨料的快速碱-硅酸反应无明显影响,即:不同标准试验方法对结果相差不大;当液相碱含量超过一定量时,疑似活性骨料和非活性骨料也会产生碱-硅酸反应危害。该研究结论可为工程水泥碱含量控制值提供参考。

Features of Salt－Affected Soils and Salinization Hazard in East Asia and Its Neighboring Regions

Asia is the largest distribution area of salt-affected soils in the world. Very few countries in Asia couldescape from hazard of salinization. This paper deals with various salt-affected soils spreading in East Asiaand its neighboring regions (including China, Japan, Kampuchea, Democratic People’s Republic of Korea,Republic of Korea, Laos, Mongolia, Burma, Thailand and Vietnam). Principles of occurrence of salinization,and features of salt-affected soils in these regions have been studied in the present paper. Based on studieson types, features and distribution patterns of salt-affected soils, a salt-affected soil map of East Asia andits neighboring regions has been complied. Mechanism and manifestation of the salinization hazard on theregional agriculture and ecological environment, measures of preventing salinization hazard and exploitingsalt-affected soils in these regions are also discussed.