5 replies to this topic

[Narnia]

Dear All,

Some clarification is required about assessment of soot blowers that for circulating fluidized bed boiler of capacity 45 tph operated on coal having sulpher contents > 6 % and ash contents > 30% needs to have soot blowers are not. Kindly suggest.

Is soot blowers requirement are related with the boiler capacity??

Thanks

[ankur2061]

Narnia,

I don't think soot blower requirement has anything to do with the capacity because soot deposition occurs over a period of time. Some coals will have more ash content and metals whereas some will have less of them. This will impact only the time for the deposit to occur on the tubes, longer or shorter. So Soot blowers are required irrespective of the capacity of the boiler.

I am attaching a nice little article on soot blowers.

Regards,
Ankur.

Attached Files

•  Soot_Blowers.pdf   108.98KB   42 downloads

[Narnia]

Thanks for your reply,

is soot blowers requireements are also check with the type of boiler.

for CFB is it required.... bz some vendor quotes that due dry nature of ash soot blowers are not required for CFB. your input is required on it

thanks

[ankur2061]

Narnia,

Frankly speaking, I have no exposure to Circulating Fluidized Bed boilers and cannot give an answer on a personal basis. However, I would generally trust the vendor's design for package items since the reputed vendors know their business and are not going to give you something that will not work. Issues with vendor's design only arise when the original specification for the inputs to the package has deviated. Vendors can claim indemnity from penalty if it is proved that whatever information that was provided to them for the design of the package was incorrect or during commissioning the input parameters have changed.

Regards,
Ankur.

[Narnia]

OK,

I am confused in a way that some vendors are proposing them & some are not... but what will be the actual requirement is not clear to me.

I need to know the normal practice of already installed similiar units in world wide & with some clarifications.

thanks

[kkala]

Local PPC (public power corporation) lignite boilers inject pulverized lignite into the combustion chamber and seem to be equipped with soot blowers (*). Lignite is burnt in fluidized state. Analysis and other data of local lignite can be found in the abstract (in English) of http://irakleitos.ntua.gr/dns/92.pdf.
Not having experience on lignite / coal boilers, I can tell that two heavy fuel oil boilers for refinery service had been ordered with soot blowers, required in the duty specification. Flue gases would be expected to drift some ash particles on boiler tubes, needing periodic cleaning, at least in ordinary designs of coal boiler. It is not indicated that the vendor offers a new alternative, http://www.energy.eu...ons/0609-02.pdf. Moreover prototype designs, not having tried before, are usually unacceptable.
Most probably you are making bid evaluation for a "CFB" boiler, so all vendors should offer on the same basis. I would issue a supplementary note to bidders, asking for soot-blowers (e.g. on superheater, circulating tubes, economizer) unless a bidder gives references of installed boilers without soot-blowers. Then I would visit the referenced boilers to assess the case.
In such cases "better to prevent than cure". I remember a case of a compressor (erroneous data by design), replaced three years after start -up.

(*) This is found in http://invenio.lib.a...4.pdf?version=1 but it is written in Greek. Soot blowers are mentioned in chapter 2.3.1.1. Google title has a note of 25 soot blowers. Present note mainly for kkala's reference.

Edited by kkala, 19 December 2011 - 07:36 AM.