碱渣回填地下废弃盐腔室内一维沉降试验研究

发布时间：2018-02-09 11:56

本文关键词： 回填碱渣盐腔沉降絮凝　出处：《岩土工程学报》2014年03期 　论文类型：期刊论文

【摘要】：盐矿水溶开采产出卤水的同时会在地下形成大量的废弃溶腔,而盐化工企业利用采出的卤水制碱时会产生大量的固体废渣(即碱渣),将碱渣与饱和卤水混合制成浆体注填到废弃盐腔的过程称为碱渣回填废弃盐腔。碱渣在充满卤水的溶腔内的沉降特性对回填效果会产生重要影响,作为初步研究,对两种不同类型碱渣与饱和卤水混合而成的碱渣浆进行了室内一维沉降试验研究。试验发现:黏粒含量少的碱渣浆絮团发育程度低,絮团小而相互独立,沉降类型为絮凝均匀沉降,黏粒含量多的碱渣浆絮团发育程度高,絮团大而联结成网,发生絮网沉降;碱渣浆沉降过程可以分为4个阶段:絮凝阶段、沉降阶段、主固结阶段和次固结阶段;对比两种碱渣的沉降过程发现,发生絮网沉降的碱渣浆在前3个阶段用时均较长;沉降基本结束后,形成的沉积体孔隙比较大,沉积体内仍含有大量的自由水。本研究揭示了两种不同类型碱渣的一维沉降规律,为进一步探索碱渣沉降固结机理及现场碱渣回填废弃盐腔工程提供一定参考。
[Abstract]:Salt ore water solution mining will produce brine at the same time will form a large number of underground cavities, In salt chemical enterprises, a large amount of solid waste residue (i.e. alkali slag) will be produced when the brine is extracted for alkali production. The process of mixing alkali slag with saturated brine to fill waste salt cavity is called alkali slag backfilling waste salt cavity. The settlement characteristics in the solution chamber of the brine solution have an important effect on the backfill effect. As a preliminary study, two kinds of alkaline slags mixed with saturated brine were studied by one-dimensional sedimentation test in laboratory. It was found that the flocs with less clay content had low development degree, and the flocs were small and independent of each other. The sedimentation type is flocculation uniform settlement, the flocculation of alkali slag slurry with more clay content is of high development degree, the flocs are large and connected to form a net, and the sedimentation process of alkali slag slurry can be divided into four stages: flocculation stage, settling stage, and so on. Comparing the sedimentation process of the two kinds of alkali slag, it is found that the alkali slag slurry with the floc net sedimentation takes longer time in the first three stages, and the porosity of the sedimentary body formed after the settlement is basically over. There is still a large amount of free water in the sedimentary body. This study reveals the one-dimensional settlement law of two different types of alkali slag, which provides a certain reference for further exploration of the consolidation mechanism of alkali slag sedimentation and the engineering of waste salt cavity backfilling of alkali slag in the field.
【作者单位】：岩土力学与工程国家重点实验室(中国科学院武汉岩土力学研究所);西南资源开发及环境灾害控制工程教育部重点实验室(重庆大学);
【基金】：国家自然科学基金项目(51304187);国家自然科学基金面上项目(41272391)
【分类号】：TU433

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