The Lime kiln was experiencing high dP emissions from the change over between limes. Midwesco completed an inspection and recommended to utilize fiberglass filter bags with an ePTFE membrane finish. The result is low emissions with a dP of 2.5 - 3.0
 A Canadian steel mill was experiencing problems with its AAF pressure reverse air collector. The unit is on a lime kiln that supplies lime to the main steel plant. This collector was experiencing a serious problem both from the standpoint of emissions and the bottleneck for the kiln production.
The kiln staff advised Midwesco® that when the kiln changes from dolomitic to high calcium lime, the unit is running at 4 - 5.5” dP pre-change and within 2 - 3 days, the dP goes up in all compartments to around 8” dP, which is problematic from an operations standpoint. When the kiln switches over from a high calcim lime to dolomitic lime, they take a pause at the kiln and ‘super clean’ the bags. When the compartment goes online the baghouse operates well at 3.5” w.g.
Midwesco’s engineering staff conducted an inspection to determine the overall condition of the unit and the tubesheets and thimbles specifically. Midwesco® recommended utilizing a fiberglass with ePTFE membrane filter media along with some structural corrections.
As a result, the lime kiln has experienced very low dP and almost zero emissions. The lime kiln has been able to run at peak production. The lime kiln has made product-shifts using both the high calcium and dolomite lime with no problems or increase in the delta P. The collector is running continuously at a 2.5 - 3.0” dP. |