Puffing boiler

Varied boiler firing configurations are found in hog fuel boiler applications, including dutch oven, fuel cell, spreader stoker with traveling or vibrating grates, and cyclone stoker types. As stated previously, the spreader stoker is the most widely used of these configurations. Spreader/stoker boilers in the pulp and paper industry often have an air swept spout added to the front of the boiler to feed bark down on top of the coal.14 Wood is puffed at one-... 

Balanced-draft or induced-draft furnaces and boilers are intended to be operated with a small negative pressure (ca. -0.1 inch H O) just below the first row of convective tubes, that is, just below the shock tubes. If we operate such a piece of equipment with a severe shortage of air in the firebox and massive air in-leakage in the convective section, it may sometimes experience thumping, puffing, or vibration. 

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