Research On Control System Of Mine Water Safe-Discharge Based On Water Hammer Protection

The water conveyance system with long distance and high height has been widely utilized in many spheres. With the development of deep mining technology, the mine drainage system has a influence on the safety production increasingly. And the water hammer seriously can cause severe safety misadventures like casualties and device destruction, submergence the pump stations, loss of life and personal injury. Especial for the drainage system with these characteristics: long distance, piping layout complex, the water hammer produces great effect. There will be an irretrievable tragedy, if a water hammer accident happens in a water drainage rescue process. The great achievements resulted from researches about water hammer prevention and protection have given an impetus to the development of water drainage system. But for the drainage system with narrow and small space, the protection measures relies on enhancing safety coefficients mainly. The water hammer pipe vibration and impact, long-term accumulation of pose a safety hazard, especial for the automation control or unattended automatic mine water discharge system. the start-stop control of water pump and the switch on-off control of mine waterdischarge valves become the key link.On basis of the analysis of three drainage condition: normal drainage pump,emergency and rescue drainage and using the combining method of water hammer protection theory, case and experiment, the mine water discharge water hammer protection method is built based on the hydraulic control valve speed regulating system and the mine water discharge system security control system is shown, in order to solve the long distance, high lift, piping water hammer problems of complex coal mine water discharge system.(1) On basis of the analysis of normal, emergency and rescue drainage, the water discharge control system for water hammer problems is researched. The water hammer protection method by using the speed regulating hydraulic operated gate valve is put forward for the mine drainage pump valve shutdown of water hammer protection problem in small space. And the optimal order law and speed control valve is the key to solving the problem of water hammer,which leads to the main modules of emission control system and it lay the foundation for subsequent control valve of the waterproof design of control system of hammer and module development.(2) Through the study of producing and fluctuation process of water hammer,a mathematical model for water hammer wave is established based on thecharacteristic method. The boundary conditions of water hammer control in mine drainage is studied and the optimal valve adjustment of simplex model is constructed, By combining the simple search optimal valve adjusting decision based optimization method and dynamic programming speed regulation valve search algorithm, the optimal solution of multi-stage valve regulating law is obtained. Taking the Zhujiajian mine as an example, it is concluded that the optimal valve adjustment strategy for optimum valves closed for two phase shifting, namely the valve stroke within 2/3 before at a speed of 0.01 m/s uniform in the valve; within 1/3 after close the valve stroke to 0.01 m/s uniformly retarded velocity of closing valves, and the total valve is 44 s.Compared to the result of valve close at a constant speed, the optimal order law of uniform-uniformly retarded shut valve water hammer pressure amplitude decreases about 50%.(3) On basis of the theoretical analysis of optimal valve adjustment, the control valve water hammer system control scheme and the implementation process are designed. And the parameters such as pipeline vibration, pressure and flow are test with the different valve shut down sequence law at the scene. It is concluded that the acceleration of x, y, z amplitude have a 5, 9.17, 7.67 times of acceleration displacement amplitude to use an optimal decision-making order law shut valve, and the maximum impact pressure of the valve close at a constant speed change from 4.87 MPa to 3.47 MPa, and the valves closedmulti-stage shifting process numerical data has a good agreement with the test data, the error within 5%, which verified the effectiveness of optimal valve to adjust water hammer protection and the correctness of the numerical results.(4) In order to implement the mine water safety control system based on water hammer protection, the four main modules that affect the mine water safety control system are designed: water hammer electric hydraulic operated gate valve, mine water pump room traffic monitoring, bus communication and wireless signal transmission, negative pressure control valve. Considering the complicated factors of mine strong flow sensor signal interference, a denoising algorithm based on LWT-G-FLP is proposed, in order to improve the accuracy of signal acquisition. The researched of technology and control strategy is applied in the Zhujiajian mine of Luliang Yang county of Liliu group and Jingfang mine of Changzhi mountain coal group, and the vibration of the pipeline also has been significantly improved. The road vibration displacement of water hammer efficiency could be improved by more than 60%, which is controlled in the range of 10 mm basically and caused by water hammer pressure value drop by more than 67%.The electro-hydraulic hammer on-off waterproof technology of safety of reasonable water hammer control strategy development is put forward, which provides a theoretical basis and technical support for the safety of the mine water discharge.