Number of startups during boiler service life

[wayuu1981]

Hello, is there any standard or common practice to define the number of startups during a boiler service life (cold, warm and hot startups).

Our company is working on the bid terms for a new coal fired utility, 280 MWe, ACFB boiler, and we would like specify a minimun number of startups during service life (the higher the better) but, we are not sure about how many to request.

In the same area, burning the same coal, and using the same thecnology (ACFB boiler, condensing turbine with reheating, natural circulation), we are erecting a 150 MWe utility, and the boiler manufacturer guaranteed at least 120 cold starts, 1200 warm starts and 3000 hot starts during a 30 years service life. Are these values common? can they be increased? is ussual for a boiler manufacturer to receive this kind of requirements?

Thanks in advance for your help

Javier Guevara E.
Projects, Mechanical Engineer

 

[metengr]

I know of no standard because plant operation is case-by-case specific. The service conditions usually are defined by the owner of the project. The owner must decide on how the plant will be operated - base load, load following, two-shift operation, or off-line on weekends.

 

[wayuu1981]

Thanks for your quick reply,

As it has been ussual where the plant is going to be erected, it will be originally considered as base load but after some years it will operate at cycling load according to market requirements.

According to that, what I would like to know, or at least to have an idea, is about for the plant I'm describing (280 MWe coal fired utility, ACFB boiler, bituminous-B coal, natural circulation, condensing turbine with reheat, closed condenser cooling cycle, etc) what will it be an acceptable number of starts during service life, what are the numbers commonly used by manufacturers when no specific requirements given by project's owner

Javier Guevara E.
Projects, Mechanical Engineer

 

[metengr]

Alright, assuming a 30 year economic life of the asset;

Unit
Cold starts - 1,500

Warm starts - 4,000