Influence of asphalt composition upon the thermodynamics performance of a mixing plant

Rotary kiln process: An overview of physical mechanisms, models and applications

“…The correlation proposed by Küssel et al [91] lies close to that given by Hausen [92,93]. Huchet et al [86], Piton [97], Piton et al [87] and Seghir-Ouali et al [98] all proposed correlation (13)…”

“…Wes et al [85] proposed the correlation in logarithmic form to estimate the wall-solid thermal exchange coefficient. The correlation proposed by Tscheng and Watkinson [75] and used in most research papers (Huchet et al [86], Piton et al [87]) is as follows (5):…”

“…with 𝜉 𝑎 = [1.82 × 𝑙𝑜𝑔(𝑅𝑒 𝐷ℎ ) − 1.64] −2 , 2,300 < 𝑅𝑒 𝐷ℎ < 10 6 , and 𝐷 ℎ 𝐿 𝑘𝑖𝑙𝑛 ⁄ < 1. Gunnarsson et al [92], Huchet et al [86] and Piton et al [87] all used correlation (11) below, as established by Gorog et al [93].…”

“…Lebas [89] proposed two correlations for natural and forced convection; these correlations gave rise to the ℎ 𝑒𝑥𝑡 values of 0.26 W.m -2 .K -1 and 3-40 W.m -2 .K -1 , respectively for natural convection (with an exterior wall at 175°C, in 20°C ambient air) and for forced convection (with a wind speed of 4 to 100 km/h) [89]. Huchet et al [86] and Piton et al [87] also provided a correlation to estimate ℎ 𝑒𝑥𝑡 , based on Nusselt's number (see Table 3, where 𝑑 𝑘𝑖𝑙𝑛_𝑒𝑥𝑡 is the outer diameter of the rotary kiln (m), and 𝜆 𝑎𝑖𝑟 the thermal conductivity of air (W/m/°K)). The above correlation has been validated for 𝑅𝑒 𝜔 numbers between 1.1×10 3 and 5.8×10 4 , as well as for 𝑅𝑒 ∞ numbers between 0 and 3×10 4 .…”

Energy efficiency of flights rotary kiln

“…-The use of recycled materials gives rise to a temperature augmentation as discussed in a recent paper [6], -a secondary air flow passage is responsible of the wall cooling when none recycled materials is formulated.…”