油酸钠浓度对泡沫稳定性的影响

    Study on the influence of sodium oleate concentration on the stability of foam

    • 摘要: 本文以油酸钠为起泡剂,利用动态泡沫分析仪研究了其浓度对泡沫稳定性的影响。由高分辨率图片可以看出,油酸钠浓度越高,初始产生的气泡越小,气泡间的液膜厚度越大。泡沫从产生至衰减过程泡沫体积、平均气泡半径、泡沫体积稳定性和泡沫含液量等特性参数测量结果表明,不同浓度油酸钠条件下产生的泡沫稳定性顺序为:6×10−4 mol/L≈8×10−4 mol/L>1×10−3mol/L>4×10−4 mol/L。Laplace方程推导表明随着油酸钠浓度的增加,溶液的表面张力逐渐减小,ΔP也逐渐变小,液膜排液速率下降,气泡兼并速度变慢,泡沫稳定性变高。但是当油酸钠浓度增加至1×10−3 mol/L时,产生的泡沫含液量最大,此时重力排液过程占主导作用,因此出现泡沫稳定性降低的现象。本研究证实了起泡剂浓度对泡沫稳定性具有重要的影响。在实际生产中,矿浆浓度和药剂用量对药剂浓度的影响很大,合理调节两者范围对于改善泡沫浮选具有至关重要的作用。

       

      Abstract: In this study, the dynamic foam analyzer is used to study the effect of sodium oleate(NaOL) concentration as the frother on the stability of the foam. High-resolution images show that the higher the concentration of NaOL, the smaller the initial bubbles generated and the thicker the liquid film between the bubbles. The measurement results of characteristic parameters such as foam volume, average bubble radius, foam volume stability and foam liquid content during the process of foam generation and attenuation indicate that the stability order of foam generated under different NaOL concentrations is: 6×10−4 mol/L≈8×10−4 mol/L >1×10−3 mol/L >4×10−4 mol/L. The Laplace’s equation calculation illustrates that with the increase of NaOL concentration, the surface tension of the solution gradually decreases, and pressure difference(ΔP) gradually decreases, leading to the decrease of liquid film discharge rate and bubble merging speed, which manifested as the increase of foam stability. However, when the NaOL concentration increases to 1×10−3 mol/L, the liquid content of the generated foam is the largest, then gravity drainage dominates, so the stability of foam decreases. This study confirms that the concentration of frother has an important influence on the stability of foam. In actual flotation, pulp concentration and reagent dosage have a significant impact on reagent concentration. It plays a vital role in improving flotation to adjust them reasonably.

       

    /

    返回文章
    返回