How To Increase the Operating Safety and Installation Availability of Heat Transfer Plants
Emergency Stacks and Emergency Air Valves:
In wood-fired power plants, in order to decouple the high residual heat in the combustion system from the thermal oil system, an emergency stack can be connected, as long as the heater is not connected directly with the fire box.The hot gases can be discharged away from the heater to the atmosphere through the stack. This stack must be care fully designed, however,especially if it is still located with in the building and not, as shown in this picture, outdoors .It isessentialto investigate at least the following in advance: Expected gas exit volumes and gas temperatures; Flammable objects in the surroundings (trees, fuel stores, roof areas, etc.); Dust and sparks; Could road users be distracted by the stack flare (if roads pass close by to the power plant)?; Position taken by the approving authorities and insurers, are there any requirements?; Automatic or manual operation of the emergency stack? Deciding factor?; How many function tests guarantee safe triggering?; Opening must take place without pressure and power, otherwise too little safety is provided; Is the functionality of the system independent of weather conditions? What damage could occur if the stack opens during heavy rain or other adverse conditions?; When the stack opens, does it present any other hazards within the power plant?
(Picture: Heat Transfer Technique / Vogel Communications Group )
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