Research On Surface Subsidence Characteristics And Solutions Of Land Reclamation In Drilling Solution Mining Area

The recovery rate of drilling solution mining is very low at present, it is very imminent to heighten the synthesized recovery rate of the mineral resources. The mining of mineral resources lead to a huge amount of arable land being destroyed, it is very acute to reclamation the destroyed arable land. This thesis has based on surface subsidence monitoring and land reclamation and synthesized recovery rate of the mineral resources, and land circulation in the zengjiahe sodium sulfate anhydrous mining area, which has discussed the characteristics of surface subsidence monitoring and land reclamation situation, method of improving the recovery rate and the economic benefit of land circulation in the this mining area. The thesis has processed, predicted and analyzed the monitoring data of mining area at same time. This thesis has obtained the following conclusions:(1) This thesis has analyzed the monitoring data, then applied Richards and its special model to analyze surface measured settlement, compared prediction accuracy of the different models, and drawn a conclusion:Richards model has the best prediction accuracy of all, which has maximum fitting Correlation Coefficient and the minimum root mean square error (RMSE). On the basis of the predicting, this thesis has applied BP neural network model to amend the random prediction error of Richards model, then obtained corrected prediction value of Richards-BP combined model, and improved prediction accuracy.(2) The current land circulation policy allows the surface subsidence and deformation values break through the limitation of existing regulations, through analyzing the mineral resources utilizing situation and existed work, the thesis has proposed a program which improves the recovery rate of associated sodium sulfate anhydrous, namely through multi-well connected technology, connecting cavity which being full of saturated brine, then recycling sodium sulfate anhydrous by machinery transporting brine.The technology can improve the recovery rate 45% at least.(3) Using fuzzy evaluation model to evaluate the economic benefits of land circulation in mining area, then select four aspects evaluating index of economic benefit, including rural economic development index, improvement of mining revenue index, improvement of farmers’lives index, and agricultural industry development index, and arrive at a conclusion at last:it is generally in a "good" level that the economic benefits of land circulation in mining area, land circulation project has achieved relatively good results.(4) In connection with feature of drilling solution mining area, the thesis has proposed appropriate reclamation countermeasures, including taking full advantage of surface subsidence and its prediction value to optimize land reclamation program, strengthening environmental monitoring, and the land ownership after land circulation et al.The thesis has analyzed surface subsidence monitoring data, evaluated synthesized recovery rate and land circulation in the zengjiahe drilling solution mining area at same time. Then the thesis has obtained surface subsidence characteristics and the synthesized economic benefits, and advanced technology which improved synthesized recovery rate in the zengjiahe drilling solution mining area. At last, the thesis has proposed appropriate reclamation countermeasures which based on surface subsidence, land circulation, and mineral resources recovery mining.