Assessing the Chargeability and Separability of Oat Groat Particles through Sieving Combined with Triboelectrification-based Approach
Assessing the Chargeability and Separability of Oat Groat Particles through Sieving Combined with Triboelectrification-based Approach
复制标题
通过筛分结合基于摩擦起电的方法评估燕麦颗粒的带电性和可分离性
DOI：
10.1016/j.seppur.2021.119486
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发表时间：
2022
影响因子：
8.6
通讯作者：
Solmaz Tabtabaei
中科院分区：
文献类型：
--
作者：
D. Konakbayeva;Solmaz Tabtabaei
采用联合筛分法和摩擦-静电分离法对脱壳燕麦颗粒进行分选。通过该工艺，在53 ~ 425 μm的6种不同孔径下对燕麦粥进行初步筛选，得到6个不同馏分，包括6个富淀粉馏分和6个富麸皮馏分，其中富麸皮馏分的蛋白质浓度（15.5 ~ 19.6%）显著高于富淀粉馏分（9.7 ~ 14.0%）。蛋白质含量与平均颗粒直径（D50）呈线性关系（R2= 0.9554）。所有筛分的摩擦充电行为被评估为颗粒大小和蛋白质含量的函数。当层流空气流速（Re = 2091）与聚四氟乙烯（PTFE）摩擦充电管接触时，富膜颗粒的电荷质量比（nC/g）高于富淀粉颗粒。在层流空气流速下，将比电荷（nC/g）值重新计算为电荷密度（nC/m2）值，并观察到电荷密度与蛋白质含量之间有三个阶段的递增趋势。富淀粉馏分在湍流（Re = 4182）空气流速下表现出完全不同的摩擦充电行为，这是由于其细小颗粒的表面体积比大，导致颗粒与壁面碰撞增强，最终获得更高的比电荷值。孔径为106 μm、蛋白质含量为10.1%的富淀粉组分，通过单级和多级摩擦静电分离工艺进一步分离，蛋白质含量显著提高约80%，蛋白质分离效率超过55%。
The possibility of fractionation of dehulled oat groat particles was assessed through combined sieving and tribo-electrostatic separation approach. Through this process, oat groats were initially sieved at six different aperture sizes of 53 to 425 μm, resulting in the production of twelve different fractions including six starch-rich fractions as well as six bran-rich fractions among which the bran-rich fractions had significantly higher protein concentration (15.5–19.6%) compared to the starch-rich fractions (9.7–14.0%). A linear relationship (R2= 0.9554) was found between protein content and mean particle diameters (D50) of all sieved fractions. The tribo-charging behavior of all sieved fractions was assessed as a function of particle size and protein content. Bran-rich particles despite their large particle sizes were acquired higher charge-to-mass (nC/g) ratios compared to starch-rich fractions at the laminar air flow rate (Re = 2091) in contact with polytetrafluoroethylene (PTFE) tribo-charging tube. To exclusively evaluate the tribo-charging behavior of the fractions as a function of protein content, the specific charge (nC/g) values were recalculated to charge density (nC/m2) values and a three-stage incremental trend was observed between charge density and protein content of the fractions at the laminar air flow rate. Starch-rich fractions exhibited totally different tribo-charging behavior at the turbulent (Re = 4182) air flow rate due to the large surface-to-volume ratio of their fine small particles that resulted in enhanced particle–wall collisions and eventually acquisition of higher specific charge values compared to their equivalent sieved bran-rich fractions. The starch-rich fraction sieved at aperture size of 106 μm with protein content of 10.1% was further fractionated through single- and multi-stage tribo-electrostatic separation processes where its protein content was sharply enhanced by ~80% equivalent to over 55% protein separation efficiency.