According to the national policy and market demand,it’s the good time of transformation and upgrading for coal Industry in recent years, especially as the transformation speed of coal-fired boiler become faster and faster, pulverized coal boiler and pulverized-coal preparation has become a hot investment market .It’s known that a large amount of granding mills from SBM company has been applied to pulverized coal production in 2015, which are equipped with auxiliary system to ensure the safe production of making coal powder.
Coal powder is inflammable and explosive,so it needs more attention to fire and explosion protection in the prpcess of coal powder production . LM Series Vertical Roller Mill and MTW Series Euro-Type Trapezium Mill are often used in production of coal powder.The central control system will play a core role while processing with Nitrogen-making system and carbon dioxide extinguishing system working together to refrain from fire and explosion
The central control system：
The central control system use industrial pc as the core unit, through a variety of communication technology to read the PLC (programmable controller) or ECS (intelligent control system) and capture the status of the device, according to the state of device, field equipment are controled by computer introductions, thus implement the remote control of equipment, records equipment information and analysis,print the report about how the equipment works.
1．The central control system of LM Series Vertical Roller Mill make the state of controlled production process focus on the display through integrative cooperation of industrial pc，PLC，sensor and other electrical components. You can check the oil temperature, air pressure, CO content, etc with a small mouse ,the remote control is also available.
2.MTW Series Euro-Type Trapezium Mill was equiped with specifically designed intelligent control system.Adopting EPC intelligent control system,the control system can implement both centralized control and remote control at the same time, using mobile terminal equipment such as Ipad, mobile phone,you can check the operation process of the production line.
pulverized-coal preparation system from SBM
Safety assistant system:
1.Nitrogen-making system ：In the production of coal powder, the main role of nitrogen-making system is to separate and purify nitrogen of the air for fire fighting，the nitrogen can be compressed into liquid and stored.The liquid nitrogen will absorb heat and cool temperature while vaporization in the process of fire fighting .
The oil removal device will remove most of the water ,oil,dust in the compressed air in Nitrogen-making system ,after that the air will go into refrigeration compressed air drier for second dehydration,then dust filter will remove most of dust in the air.The air will go through the gas tank buffer ,then enter the PSA oxygen nitrogen separation system which was filled with adsorbent. Clean and compressed air go into the adsorption tower from the bottom, Air was spread by the air diffuser ,enter the adsorption tower evenly, Oxygen and nitrogen will be seperated after adsorption and separation,then the nitrogen exits from the export to Nitrogen buffer tank .
2.Carbon dioxide extinguishing system: carbon dioxide is a good fire extinguishing agent with characteristic of non-conductive, inertia, low toxicity and no polution after fire, and it also have other advantages like extensive sources, easy production and low prices. The main effect of carbon dioxide extinguishing principle is to achieve Stifle effect with a part of cooling effect .
The main components of Carbon dioxide extinguishing system are gas cylinders, choice of container valve, check valve, valve, drive, header pipe, metal hose, nozzle, pressure feedback device, control panel, system of pipeline fittings, fire extinguishing agent conveying pipeline fittings and air cylinder bracket, etc.
3.The temperature detection fire alarm system: when the temperature of the protected area exceed the preset alarm temperature, alarm signal will be transmitted to the host, the alarm host will give the alarm instructions .similarly,concentration of carbon monoxide alarm signal can be connected with the fire alarm host through the signal lines, when the concentration of carbon monoxide concentration exceed the preset, The alarm host will give the alarm instructions, then the alarm host begin countdown 30 seconds, countdown to zero, the alarm host will give a signal to carbon dioxide extinguishing system , The nitrogen bottle group will open the corresponding electromagnetic valve, nitrogen activated carbon dioxide extinguishing system at the fire alarm region.The system is equiped with automatic, manual, mechanical emergency manual and emergency start/stop the four kinds of control mode.
4,The gas on-line analysis system is designed to analysis gaseous content of pulverized coal making process. This system can test the components concentration of the sample automatically and offer two series of figure for alarm. It can be used for alarm or interlock control.The perfect cooperation of main and asstant equipments makes the pulverized coal production working with high-performance,environmentally，friendly and safely .Whether from its own characteristics or national policy support, this pulverized coal will become a typical representative of the future fuel power equipment.
The central control system of making pulverized coal from SBM