水基溶液起泡性能评价方法比较研究

Comparative study on the experimental assessment methods for water-based foam behavior

泡沫液的发泡比和半衰期是表征起泡剂特性的基本物理量。选用十二烷基硫酸钠为典型的表面活性剂,测量了不同质量分数溶液的表面张力,得到试验条件下的临界胶束浓度(CMC)为0.25%,采用改进的RossMile法、搅拌法和测压力法,在相同的环境下对同一溶液进行发泡试验,其中测压力法可以得到表征重力排液和扩散排液过程等泡沫破灭过程的定量数据。结果表明,发泡比因起泡方法的不同而有较大差异,在相同质量分数下,测压力法的起泡量最大而搅拌法的起泡量最小,3种方法所产生的发泡体积随质量分数的变化趋势一致,当表面活性剂质量分数≥0.25%(CMC)时,搅拌法、Ross-Mile法和测压力法的发泡体积比为1∶1.25∶1.36。3种方法所产生泡沫的半衰期随表面活性剂质量分数增加而增大,达到最大值后缓慢减小,有相似的变化趋势,测压力法、Ross-Mile法和搅拌法的半衰期之比约为1∶3∶6,分析了3种方法所产生泡沫的发泡比和半衰期差异的原因。

The present paper is to make a comparative experimental study on the water-based foam behavior by choosing the study of foam-producing characteristic features and the lauryl sodium sulfate as the typical surfactant sodium while doing and observing the three foaming experiments under the environment temperatures. In proceeding with our research,we have taken the foaming ratio and the half-life of the foaming liquid as the basic physical quantities to represent the behavior of the foaming agent.As a matter of fact,we have measured the foaming liquid surface tension at different concentration levels and found it is 0. 25%.Moreover,in order to improve our experiments,we have improved such foaming methods,as the Ross-Mile method,the mixing method and the pressure measurement method,respectively,from which we have gained the quantitative data by the pressure measurement method in the process of the bubble burst,including the gravity drainage and spreading drainage. The experimental results we have achieved show that the foaming ratios vary greatly in different foaming ways. For example,the application of the pressure measurement method can help us to gain the maximal foaming product,whereas the mixing method can only allow us to get the minimal foaming product under the same solution concentration.At the same time,when we use the improved Ross-Mile method,the mixing method and the pressure measurement method, it would be possible for us to get different foaming volumes,respectively,by holding the same developmental trend with the increment of the solution concentration. And,in case when the surfactant concentration is greater than or equal to 0. 25%,the ratio of foaming volume produced by the said three methods would be equal to 1： 1. 25： 1. 36. In addition,the half-lives of the abovementioned foams produced by using the above foaming methods have been found rising at the beginning with the increase of the solution concentration and then tend to reach their peak data,and finally turn to decrease slowly in the end. And,then,the developmental trends of the foam half-life found by using the above said three experimental methods prove to be similar. The ratio of the foam half-lives given by the above said methods,has been found approximately to be 1： 3： 6 under the same solution concentration.Through careful analysis of the differences of foaming volume and half-lives of the three said methods,we can arrive at a conclusion that the diversity of the foaming generating process tends to lead to the differences of foam-given properties.