Effect of Mixed Nanobubble and Microbubble Liquids on the Washing Rate of Cloth in an Alternating Flow

Abstract

It is well‐known that laundry waste water contributes to water pollution, and the need to reduce the amount of detergent used is widely recognized. Predominantly, research has focused on the washing effects of microbubbles and nanobubbles, and mechanical work was found to account for about 50 % of the washing effect on the cloth. In the present research, mixed nanobubble and microbubble water and four types of surfactants (including a commercial cleaning liquid) were investigated in an alternating flow system. The nanobubble water achieved a washing rate greater than that of ion‐exchanged water. However, the microbubble water had the same washing rate as ion‐exchanged water. Moreover, nanobubbles mixed with an aqueous solution of surfactant exhibited a washing rate that depended on the ionization of the surfactant: the mixture with nanobubbles and anionic surfactant exhibited a washing rate that was higher than that of aqueous anionic surfactant solution without nanobubbles. The surface tensions of nanobubble water and mixed nanobubble anionic surfactant were lower than those without nanobubble, respectively. Also, there was no advantage in mixed microbubble liquids. These results provide evidence of an enhanced washing effect by nanobubble mixtures in liquids.

Interpreting the interfacial and colloidal stability of bulk nanobubbles

“…Though bulk nanobubbles are a relatively new field, because of their unusual longevity they are already attracting a lot of industrial attention and many potential applications have been proposed. Thus, there is immense scope for nanobubbles to impact and even revolutionise many current industrial processes such as wastewater treatment, 4 surface cleaning, [5][6][7] froth flotation, [8][9][10][11][12] nanobubbles as ultrasound contrast agent, [13][14][15][16][17][18][19] therapeutic drug delivery, 17,19,20 drag reduction, 21 sterilisation of bacteria, 22 enhanced germination rate of seeds, 23 promotion of physiological activity of living organisms, 24 improved blood oxygenation, 25 and improved engine performance using hydrogen nanobubbles. 26,27 To fully exploit these potential benefits, however, a thorough understanding of the formation, stability and dynamic behaviour of bulk nanobubbles is needed.…”

The effect of fabric movement on washing performance in a front-loading washer III: Focus on the optimized movement algorithm

“…Thus, washing effects are considered difficult to explain exactly in respect of the mechanical washing mechanism, such as fabric movements, mechanical action by the washers, water flow dynamics, and so on. It eventually causes difficulties in explaining the overall washing mechanism, such as new washing methods, [6][7][8][9] washing evaluation methods, [10][11][12][13][14] and simulations on washing. [15][16][17][18][19][20] Therefore, there is a need for research on the effects of mechanical action, such as fabric movement on washing efficiency, for better understanding the overall washing mechanism.…”

Production of Oxygen Ultrafine Bubble Water with Spray Injection from a Pressurized Container

“…2017 年 6 月 ISO は、微細気泡(ファインバブ ル)技術に対する正しい理解のために直径 1 µm 以下の微細気泡を「ウルトラファインバブル(以 下、UFB と略記) 」 、直径 1 µm～100 µm の気泡を 「マイクロバブル」 と定義した [1]。 UFB は水中で の長期安定性 [2]、 高い内部圧力 [3]、 負に帯電した 大きな表面積などの独特な物理化学的性質を持 つ。UFB が持つ多くの可能性は、洗浄 [4,5]、野菜 /動物種における代謝の促進 [6]、水処理システム [7,8]…”