Nonlinear chaotic characteristic in leaching process and prediction of leaching cycle period

• Published in: Journal of Central South University Vol. 23; no. 11; pp. 2935 - 2940
• Main Authors: Liu, Chao, Wu, Ai-xiang, Yin, Sheng-hua, Chen, Xun
• Format: Journal Article
• Language: English
• Published: Changsha Central South University 01.11.2016; Springer Nature B.V
• Subjects: Civil; Energy and Traffic Engineering; Energy dissipation; Engineering; Geological; Metallic Materials; Nonlinear dynamics; phase space reconstruction; neural network prediction; leaching system; leaching cycle period; chaotic characteristic
• DOI: 10.1007/s11771-016-3357-9
• ISSN: 2095-2899

A laboratory leaching experiment with samples of different grades was carried out, and an analytical method of concentration of leaching solution was put forward. For each sample, respectively, by applying phase space reconstruction for time series of monitoring data, the saturated embedding dimension and the correlation dimension were obtained, and the evolution laws between neighboring points in the reconstructed phase space were revealed. With BP neural network, a prediction model of concentration of leaching solution was set up and the maximum error of which was less than 2%. The results show that there exist chaotic characteristics in leaching system, and samples of different grades have different nonlinear dynamic features; the higher the grade of sample, the smaller the correlation dimension; furthermore, the maximum Lyapunov index, energy dissipation and chaotic extent of the leaching system increase with grade of the sample; by phase space reconstruction, the subtle change features of concentration of leaching solution can be magnified and the inherent laws can be fully demonstrated. According to the laws, a prediction model of leaching cycle period has been established to provide a theoretical foundation for solution mining.