Analysis of the Mode and Mechanisms of Destabilization of Micro Foams

Micro-foam fluid destabilizes in three ways: separation of the liquid phase, settlement, or both. In our study the effects of several factors on the way of foam destabilization were studied, including the viscosity and gel strengths of the micro-foam, the molecular weight of the foam stabilizer, speed for mixing the foam, temperature, Na⁺ and Ca²⁺ etc. The viscosity and strength of the interfacial films of the micro-foam prior to destabilization were compared with each other and the intrinsic mechanisms of the destabilization of the micro-foams were analyzed. These studies shall be able to provide technical references to the formulation of micro-foam fluids with thermal stability and salt-resistance. Generally speaking, when the viscosity and the ratio of yield point over plastic viscosity of the base fluid are low, or when medium for stabilizing the micro-foam is a kind of lightweight gel, the micro-foam destabilizes in a way of liquid separation; when the density of the base fluid stabilizing the micro-foam is high, or when the molecular weight of the gel is too high resulting an in increase in the amount of bound free water, and hence an increase in the thickness and weight of the liquid films, the micro-foam destabilizes in a way of settlement. When the micro-foam is aged at different temperatures or contaminated with different concentrations of metal ions, it destabilizes in a way of both liquid separation and settlement.