大尺寸型盐造腔相似试验研究

 基于相似理论中的量纲分析法，建立型盐造腔相似试验模型，通过试验找到一种可用于模拟造腔的型盐，并利用自行研制的模具成功制备直径为300 mm，最大高度为500 mm的大尺寸型盐。在3组不同造腔工艺下进行大尺寸型盐造腔相似试验。在试验过程中，提出一种利用饱和盐水导电特性测量腔体形状的方法。试验结果发现：造腔工艺影响腔体形状和造腔速率，主要影响因素有套管位置组合、油垫位置、造腔时间、注水流量；在分步扩展造腔工艺下，造腔效率较高，腔体形状为下大上小的倒梨形，腔体体积达到4 200 cm3，腔体最大直径达到24 cm，平均直径为20 cm，腔体高度达到27 cm，造腔过程中排出的卤水浓度达到22%左右，符合采盐工艺的要求。依据相似试验模型中的相似判据，建立模型和原型相关参数的关系，对现场造腔的设计和控制具有指导意义。

SIMILAR EXPERIMENTAL STUDY OF CAVITY BUILDING USING LARGE-SIZE MOLDED SALT ROCK

Based on the dimensional analysis method of similarity theory,the similar experimental model was established to simulate the cavity building using the molded salt rock instead of natural salt.By experiments,a kind of molded salt rock that can be used for cavity building was found.Using the self-developed mould,a kind of large-size molded salt rock was obtained,which has a diameter of 300 mm and a maximum height of 500 mm.Three groups of experiments with different kinds of solution mining techniques were conducted,and a method for measuring the cavity shape by saturated brine for its electrical properties was proposed.The study shows that the cavity shape and the cavity building efficiency are affected by the washing techniques,and main factors include the location of casing pipes,location of oil cushion,time of cavity building and water flow.The step-by-step expansion method for cavity building can induce higher cavity building efficiency,and the cavity is an inverted pear-shaped chamber with a volume of 4 200 cm3,the maximum diameter of 24 cm,the average diameter of 20 cm,and the height of 27 cm.The brine concentration is about 22%,which reaches the demand of salt mining.Based on the similarity criteria in the similar experimental model,relationship between model and prototype parameters was developed.It provides a guidance about the design and control of cavity building.