Alteration/modification of dedusting pipe

(not verified)
Posted in: , on 3. Oct. 2006 - 08:08

dear all

i think of adding one more ducting to the existing dedusting system with velocity 3500fpm. sp=-10inwg and fan capacity for the bag filter is 120000m3/hr. (bag filter for collecting cement dust) end part before goes to silo

what things should be checked before i proceed adding the pipe?

air withdrawn etc? ...need your input pls


Modification Of Dedusting Pipe

Posted on 3. Oct. 2006 - 07:50

What size is the duct you are thinking of adding to the system? Whereabouts in the system?

A small duct will not make much difference to a system of 120,000 cu.m/h but be aware that it will rob adjacent ducts of their fair share of the design airflow.

You may need to re-balance the airflows to correct this.

If you are planning a large addition, you will need to consider upgrading the fan duty. You should get an expert to analyse your proposal and advise you the best way to avoid mistakes.

If possible, ask the original equipment supplier to advise you.

Michael Reid.

(not verified)

Re: Alteration/Modification Of Dedusting Pipe

Posted on 3. Oct. 2006 - 10:31

additional pipe maybe around 8-12 inch dia. and attached to 1.7 meter ducting of the bag filter....

additional ducting equip with damper to adjust the air flow around 4000-5000 cub ft per min...

is it work...

Modification To Dedusting Pipe

Posted on 4. Oct. 2006 - 12:48

For 4000 to 5000 cfm (6,900 to 8600 cu.m/h) the duct will be 350 to 400 dia. This flow is 5% to 7% of the system total. It will affect the flow in all ducts upstream (if the connection is at the inlet to the bagfilter).

Yes, it will work for the new dust extraction point, but all other points will suffer unless you make some adjustments to the fan duty and rebalance the system.

Michael Reid.

(not verified)


Posted on 4. Oct. 2006 - 03:51

tq, i've few question;

what do u mean by adjustment of fan duty? ..changing fan blade etc

you said 5-7% compare to fan capacity so what is the acceptable percentage for us not to do adjustment or balance to system ? ...<5%

actually the upstream of the bag filter duct is only one unit separator ... do you think it still affect the system performance if add new ducting as mention before.