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What will be the effect of high level in HP drum of HRB?

How about WATER carry over into the steam system instead of steam... Not a good idea!!!

DIIK PBE

Roy Matson,

I'm almost afraid to ask, but, can you explain (without offending anyone or using expletives)?

CSA,

Just struck me as funny that someone would ask us to answer a question that way, was he texting from a cell phone or what?

Damed If I Know, Probably Big Explosion.

Regards,
Roy

It does seem like some people think they're texting their request by cell phone. If I wanted to sound like my grandfather I'd say, "Young whippersnappers need a lesson or two in respect!" But, that's the way of the world; until speech recognition gets more prevalent we're going to see more and more keystroke shortcuts on PCs as more and more people use their wireless texting "abilities" when communicating via the Internet.

I didn't understand CTTech's "test question" reference at first. But this is the kind of question one would see on some kind of exam, being written by a non-technical person who had just read some passage in a textbook or manual about carryover and it's effects. Lots of questions on various technical tests like this are very brief (because the test question writer doesn't have enough knowledge to know how to word such a loaded question) and the answer would be very obvious to someone who knew something about the topic and was preparing an exam, not to mention it's a huge answer if one considers *all* the parameters. Most of the responses (including my own) touched on only one or two of the most important responses, and I think only one included the less obvious answer about steam temp, though I've never heard of low steam temp causing gaskets to leak.

That's why I was asking what the context of the question was; it hadn't occurred to me that some people might be looking for answers to exam questions on this forum. Homework, yes. I guess this is as good a place as any to ask questions; one might even get some pretty interesting and intelligent answers.

What is the context of your question? Has your HRB (we presume that's a Heat Recovery Boiler, as opposed to an HRSG, Heat Recovery Steam Generator, as opposed to a WHB, Waste Heat Boiler, as opposed to a EGHRB, Exhaust Gas Heat Recovery Boiler) experienced a high drum level event? Was there carryover? Did your steam piping system experience a slug? Did the steam turbine get slugged?

Are you trying to understand why boiler drum level control is important?

Are you talking a high drum level or a high-high drum level? Are you talking about during a transient condition (start-up, shutdown, emergency shutdown)?

Where does the exit of the HP drum on your HRB direct the steam to?

What is the context of your question?

Another test question!

High water level in the drum can allow moisture carry over to the turbine. The control system is programmed to force a turbine trip.

Low water level in the drum can merely cause a meltdown of the heating surfaces of the boiler. Thus the control system is programmed for a boiler trip ie the turbine/generator will not trip. The difference is from an *electrical generation* perspective only.

A turbine trip will open the main generator breaker, while a boiler trip will allow one to *coast* on existing boiler pressure hoping to restore the boiler and recover from the trip.

High level in HP drum of HRB will first of all reduce the temperature of HP steam and also there will be water carry over. This may lead to damage of pipe gaskets thus leading to high steam leakage.

Reduced temperature will lead to plant shut down. Also if this wet steam is used to move some turbine the turbine blades may get damage and cosst of repair is huge.