Emergency situation Procedure and Placing Boiler from Solution
Low Water Level
Low water level, 140mm or more listed below the normal functioning level, will activate the aesthetic and distinct alarm systems (lighting of the alarm system light on the control board and seeming of the alarm system buzzer).
Should the water level are up to 250mm or more listed below the normal functioning level, the fuel oil emergency situation journey shutoff will shut, turning off fuel from the boiler. The feedwater shutoff and heavy vapor quit shutoff should be fully shut, the heater closed down totally and the forced draught follower quit after removing the heating system. Never ever attempt to provide feedwater to the boiler until the boiler has cooled down adequately, as there’s a risk of bringing relatively chilly feed right into contact with warm surface areas. When the boiler water level is brought back the boiler may be flashed up using the normal treatment.
Fire Failing
In situation of fire failing, shut the oil inlet shutoff and decrease atmospheric pressure to prevent over cooling the heating system. Cleanup the heating system thoroughly before relighting the heater. Constantly use the pilot heater for ignition, never ever attempt to relight the heater from the warm heating system refractory.
Evaporating Tube Failing
Major tube failing where water level cannot be maintained.
a) Turned off the oil provide to the boiler and if television failing outcomes from reduced boiler water level, turned off the feed provide, shut the feedwater shutoff and heavy vapor quit shutoff.
b) If television failing outcomes from a reason various other compared to low tide level, the fuel provide should be turned off but the feedwater provide should be maintained in purchase to assist in the cooling off process. When the boiler has cooled down adequately, shut the feed shutoff and heavy vapor quit shutoff and open up the heavy vapor drum duct.
c) In either situation of tube failing, maintain the forced draught follower so that the air prepare helps in bring away the leaving heavy vapor. Treatment must be required to avoid damage to the refractory by an extreme air provide. Don’t strike down the boiler unless television failing is so serious that workers could be threatened. When the boiler has cooled down, the blowdown may be used to empty the boiler.
e) When the boiler has cooled down enough, an evaluation should be carried bent on evaluate the circumstance and perform necessary repairs.
f) If tube failing isn’t major and the water level can readily be maintained, the boiler can be closed down in the normal manner.
The forced prepare air provide should be maintained to carry away vapours produced by the leaking water and the water level maintained throughout the cooling off duration. When boiler stress has dropped to 2 kg/cm2, the heavy vapor drum duct shutoff boiler may be opened up and the boiler blown down.
Method Placing Boiler
When placing a boiler from solution, the damp lay-up technique is more suitable, as it requires much less prep work and it can be quickly returned to solution. These actions are taken if the deliver is to be taken from solution for some time and are not component of normal functional routine.
1. Wet Lay-up
When the boiler remains in the cooling off process following shutdown, appropriate amounts of boiler chemicals should be infused right into the drum using the boiler chemical shot device. To ensure adequate protection of the boiler, follow the standards provided by the chemical provider. The amount of the chemicals required will rely on the problem of the boiler water and a water test should be performed before shutting down. After dosing the boiler water should sign up pH of 12, (alkalinity 300 to 400 ppm) phosphoric acid about 50 ppm, and salt sulphite 80 to 100 ppm. The high alkalinity will ensure adequate protection of the boiler. When returning the boiler to solution the chemical concentrations should be returned to normal levels and this means blowing down the boiler and filling with neglected cosmetics feed.
a) When the stress is coming close to atmospheric stress, open up the heavy vapor drum air duct shutoff.
b) When the stress is off the boiler, provide pure water until it problems from the duct shutoff, after that shut the duct shutoff.
c) Put a hydrostatic stress of 3.5 to 5kg/cm2 on the boiler. Hold this stress until the boiler has cooled down to ambient temperature level. Hemorrhage the boiler using the duct shutoff to be certain all the air is out.
Maintain a hydrostatic stress of 2 to 3.5 kg/cm2 on the boiler. Take a regular boiler water example and renew any diminished chemicals.
Preserving Boiler in Warm Problem
At sea, with one boiler being distributed through the waste heat economiser, the standby boiler should be maintained in a cozy problem by providing heavy vapor to the heating aspect in all-time low drum. This is done by shutting the heating coil drain shutoff and opening up the inlet and electrical outlet shutoffs. The boiler stress should be maintained at 0.5 kg/cm2 or over. When the heating aspect is not being used, the inlet/electrical outlet shutoffs are shut and the drain exposed. In port with the economiser closed down, the standby boiler is maintained at 2kg/cm2 or over by switching the heater on and off. Don’t use all-time low drum heating unit.
2. Dry Lay-up
This should just be undertaken if a damp lay-up cannot be performed.
a) Whilst the boiler remains warm, drain it of all water and ensure that headers are dry.
b) Remove completion item of the waterwall lower header to inspect that no water remains.
c) Provide some dry heat, electrical heating units ideally, in the heating system to advertise interior drying out.
d) When the boiler is totally dry, put some fast lime or calcium chloride in a superficial meal for positioning in the drum andheader after that shut completion plate and manhole doors.Inspect the moisture absorptive chemicals weekly at first and renew as required.
e) Cover the channel electrical outlet and shut the air inlet to the heating system.
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