Research On Monitoring Technology For Self-ignition Of Coal Stack

Coal self-ignition seriously affects the production and operation and brings great security risks to the transportation and storage of coal.The development of coal spontaneous combustion forecasting technology is severely restricted because it is difficult to describe the process of coal spontaneous combustion under different working conditions.In order to effectively prevent coal spontaneous combustion,study the spontaneous combustion characteristics of coal and select proper monitoring technology,it is necessary to find high temperature area quickly and accurately.Based on a certain port open-air strip coal pile as the research object,through analyzing the characteristics of the coal spontaneous combustion process of combining with the actual working condition of the coal yard condition,design and develop a complete set of monitoring system,to ensure that the storage of coal is safe and effective.This paper is built using COMSOL Multiphysics 5 simulation software in multi field coupling under the spontaneous combustion of the coal pile model,the spontaneous combustion process of coal stack is simulated and analyzed,the influence of the height of the heap,the angle of the heap and the wind speed on the distribution of the high temperature area in the coal pile is analyzed.According to the actual conditions of the coal pile in the coal storage yard,a reasonable monitoring scheme is proposed for the strip coal pile.Secondly,according to the actual working conditions of open-pit coal yard,low power coal wireless monitoring system based on temperature collection node system,network base station system and data monitoring center system,real-time monitoring the temperature change of the temperature field in the coal pile.The temperature acquisition node system mainly uses the thermometer to measure the internal temperature of the coal pile,using Modbus protocol to upload temperature information to network base station system based on 433 MHz frequency band;The network base station system is integrated by the receiving device and the GPRS module,the receiving device uses the 485 interface and the GPRS module to transmit the data,and drives the GPRS module to upload the obtained temperature data to the network cloud based on the mobile network.The data monitoring center system downloads the valid data and displays it on the terminal.Finally,the data monitoring center uses configuration software to build a monitoring platform.Through the data monitoring platform,the actual situation of the internal temperature of the coal pile can be monitored continuously.The historical data of different dates of coal pile temperature are examined,and the trend of its development is judged in order to make reasonable treatment.The temperature alarm record is inquired and the monitoring points of the multiple temperature alarm are processed in advance according to the alarm record.With SMS alarm function,the alarm information is sent to the staff's mobile phone in time.Wwith the sound alarm function,it can remind the staff on the spot in time to reduce the hidden danger of coal safety.