|
Based on energy security in China and the West-East Gas Pipeline Project, there is an urgent need to establish giant oil and gas reserves of the library used to the reservoir of oil, natural gas, nuclear waste and industrial refuse. Underground energy storage is generally placed in low permeability rock formations (such as rock salt, granite, etc.) as well as the porous rock. Rock salt has a very low penetration characteristics (permeability of less than 10-20m2) with good creep behavior, to ensure the tightness of the storage cavern. The mechanical properties of the rock salt are more stable, and able to adapt to the changes of the storage pressure, and rock salt easy to dissolve in water characteristics of the rock salt cavern excavation for easier and more economical. Important functions of security, peaking, environmental protection, strategic reserves, commercial operation of the underground repository. Rock salt repository built chamber process, first solve the problem of salt dissolved this to study the factors that affect the halite dissolution rate, these factors both internal factors of the ore itself is not regulation, there are external factors that can be regulated. The basis of experiments, this study halite dissolved indoor experiment to study the rock salt of dissolved area, the temperature of the solution, the concentration of the solution, the solution flow rate and bedding angle factors affect the dissolution rate. Halite dissolution of the law of the experimental study, the following conclusions: ① the dissolved surface area on the dissolution rate is not obvious, but the larger the the dissolved surface area of ??the larger dissolved quality; ② solution temperature increased a great influence on the dissolution rate in halite dissolved quickly in the high temperature, and as the temperature rises, the rock salt dissolution rate is gradually increased, the exponential relationship; ③ As the concentration of the solution increases the rock salt dissolution rate is gradually reduced, in a saturated sodium chloride solution, halite basic longer to dissolve, the curve of a quadratic curve; ④ within a certain velocity range, the rate of dissolution of the rock salt with the flow rate increases, and its relationship to the exponential relationship; ⑤ layered rocksalt bedding angle for dissolving rate, the rate of dissolution of 90 ° angle between the bedding than 0 ° a large, but the dissolution rate under the bedding angle difference not described specimens anisotropic obvious; ⑥ through the solution concentrations, temperature, and solution flow velocity, three factors on the the gray relational halite dissolution rate impact analysis can be found, the temperature is the most important factor, the influence of the solution flow rate, followed by the last concentration. The three parameters of gray related degree greater than 0.85 greater than the impact of the dissolution rate. Above study and draw conclusions, and provide a theoretical basis for further study of the flow field and concentration field distribution of the rock salt law provides the basic theoretical and experimental foundation for the rapid-made cavity.
|