Oxygen transfer to slurries treated in a rotating drum operated at atmospheric pressure
Oxygen transfer to slurries treated in a rotating drum operated at atmospheric pressure
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DOI：
10.1007/s00449-006-0088-6
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发表时间：
2006-12-01
影响因子：
3.8
通讯作者：
Poggi-Varaldo, Hector M.
中科院分区：
文献类型：
--
作者：
Barrera-Cortes, Josefina;Manilla-Perez, Efrain;Poggi-Varaldo, Hector M.
本工作的目的是确定（1）转速（N）和提升器对矿物溶液的氧传递系数（k（L））的影响;（2）在固定值N下，泥浆土壤-矿物溶液的固体浓度对kL的影响（0.25 s（-1））;在这两种情况下，处理都是在大气压下操作的充气转鼓反应器（RDR）中进行的。首先，矿物质溶液的kL在6.38 × 10（-4）-7.69 × 10（-4）m·s（-1）的范围内，这与供应有空气流的封闭旋转鼓计算的kL具有相同的数量级。一般而言，使用升降器的RDR的kL上级或等于不使用升降器的RDR的kL。对于使用升降机的RDR，kL在6.65 x 10（-4）-10.51 x 10（-4）m s（-1）的范围内随N增加，而不使用升降机的RDR的kL首先随N增加，直到N = 0.102 s（-1），然后下降。第二，关于土壤泥浆实验，kL（约。在N = 0.25 s（-1）时，观察到在低固体浓度（C-v）时的渐近模式和在高C-v时的渐近模式。这些结果表明，传质现象的指挥浆料的性质和半经验方程的形式Sh = f（Re，Sc）似乎证实了这一发现。
The objective of this work was to determine (1) the effect of rotational speed (N) and lifters on the oxygen transfer coefficient (k(L)) of a mineral solution and (2) the effect of solids concentration of a slurry soil-mineral solution on kL, at a fixed value N (0.25 s(-1)); in both cases the treatment was carried out in an aerated rotating drum reactor (RDR) operated at atmospheric pressure. First, the kL for the mineral solution was in the range 6.38 x 10(-4)-7.69 x 10(-4) m s(-1), which was of the same order of magnitude as those calculated for closed rotating drums supplied with air flow. In general, kL of RDR implemented with lifters was superior or equal to that of RDR without lifters. For RDR implemented with lifters, kL increased with N in the range 6.65 x 10(-4)-10.51 x 10(-4) m s(-1), whereas kL of RDR without lifters first increased with N up to N = 0.102 s(-1), and decreased beyond this point. Second, regarding soil slurry experiments, an abrupt fall of kL (ca. 50%) at low values of the solid concentration (C-v) and an asymptotic pattern at high C-v were observed at N = 0.25 s(-1). These results suggest that mass transfer phenomena were commanded by the slurry properties and a semi-empirical equation of the form Sh = f(Re, Sc) seems to corroborate this finding.