1962 Table 46:Temperature over time at the seam wall (TW), and in the centre of the blasthole (TC), in the open blasthole scenario shown in Figure 121 Time (hours) TWall, TW ( oC) TCentre, TC ( oC) 0 70 20 8 67.1 48.0 16 66.2 47.2 Over 16 hours the open hole wall temperature decreased by approximately 4 oC relative to its initial value, while the air temperature at the center of the hole within the reactive seam increased by approximately 27 oC. When measuring blast-hole temperature prior to loading it is important to measure the wall temperature given the large difference between the wall and air temperatures. The model was run with two common bulk product types, an ANFO and a pumped emulsion blend, to see the impact on hole temperature over time when the convective heat flow of air was replaced with conductive heat flow from the higher density bulk explosives. The bulk product initial temperature was set at 40 oC. 70/30 Pumped Emulsion/ANFO Blend Figure 122:Cross section of blast hole loaded with Emulsion Blend Bulk Product showing the temperature gradient at 0, 8 and 16 hours ANFO
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