Slabs, heat-soaking

To heat slabs uniformly with regenerative burners, the following steps are necessary and should not be compromised  

Add bottom and sidewall piers with small tempest burners through the long walls to fire under the bottom piers to pump the combustion gases down the long walls. 

Below some firing rate, for example, 10 kk Btu/hr, the burners should fire direct to increase mass flow to improve temperature uniformity, by firing direct, bypassing the regenerative beds. (The poc of these burners should exit through flue openings below the burners.) 

Example 6.7 Compare fuel requirements for a slab-soaking furnace fired with regenerative burners, and with and without added burners for pumping (stirring, circulation). (See fig. 6.21.) 

High-fire fuel input, main burners = 2.9 hr x 20.6 kk Btu/hr = 59.7 kk Btu. 

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