In a sulfuric acid plant, does a trip of the boiler feed water pump require shutdown?
Thread Content
I would like to ask the process engineers: In a sulfuric acid plant, does the shutdown of the boiler feed water pump require a full plant shutdown?
As long as the water level in the boiler drum is visible, the standby feed water pump can be started quickly without shutting down the plant; if the water level still cannot be seen even after attempting to check it, then an emergency shutdown is necessary
This issue is quite complex; it depends on how one understands the boiler. Simply put, if water can be produced, there’s no need to stop the boiler. The level gauge on the steam drum is installed at a middle position, and just because the gauge shows no water does not mean there is no water in the drum. Boilers are designed with a margin of safety; it takes experience and calculations to determine how much water remains below the gauge and how long it can evaporate. Therefore, whether to stop the boiler or not depends on one’s understanding of the boiler. Of course, doing so carries risks
What you are doing is a serious violation that will lead to severe consequences. The drum design features a low-low interlock level (the level is visible); shutdown is required when this level is reached. At this point, the remaining water volume in the drum (excluding make-up water) is sufficient to cover the evaporation rate during shutdown, preventing the drum from drying out. If the vehicle does not stop, there is a high risk of a fire breaking out, leading to a serious accident. The level gauge can no longer show the liquid level, so no one knows what the actual level is; the only option is to stop the machine for inspection.
What you are doing is a serious violation that will lead to severe consequences. The drum design features a low-low interlock level (the level is visible); shutdown is required when this level is reached. At this point, the remaining water volume in the drum (excluding make-up water) is sufficient to cover the evaporation rate during shutdown, preventing the drum from drying out. If the vehicle does not stop, there is a high risk of a fire breaking out, leading to a serious accident. The level gauge can no longer show the liquid level, so no one knows what the actual level is; the only option is to stop the machine for inspection.
Whether it’s against the rules or not depends on the circumstances. If you’re confident that you can top up the water immediately, then you can keep going; I’ve said there are risks involved, and experience as well as calculations are needed. Otherwise, you’d better stop the vehicle right away
I’m just afraid that as soon as you add water, there’ll be a loud bang, and chaos will ensue: lol
I really want to say a few words. Comments suggest that one shouldn’t stop the machine as long as water can be supplied, but I think this is incorrect. The process of supplying water should only be carried out after the machine has been stopped. If there is a severe lack of water, natural cooling is the only option; in cases of mild water shortage, water can be added slowly in small amounts. Just imagine: if the unit has a high capacity, the amount of water that evaporates is significant; by the time you request more water, the pot will already be dry. It would be better to have a low liquid level switch that stops the operation before asking for more water – that’s my personal opinion. Safety first!