Study of ethylenediammonium dichloride as a clay stabilizer used in the fracturing fluid
Clay stabilizer is the topic of a great number of studies, particularly in petroleum engineering. The organic cationic polymer is a kind of clay stabilizer with excellent anti-swelling effect. However, for tight reservoirs, the organic cationic polymer type clay stabilizers tend to increase the permeability damage caused by retention and blockage of stabilizers. Therefore, stabilizers with low molecular weight are necessary for tight reservoirs. The inhibition properties and the mechanisms of ethylenediammonium dichloride (EDD) were studied in this paper. The clay inhibition properties were studied from three aspects: swelling inhibition, clay sedimentation, and particle size distribution. Results showed that the anti-swelling rate reaches 91.98%. Control experiments showed that EDD had better inhibition property than KCl, NH 4 Cl, and poly dimethyldiallyl ammonium chloride (PDMDAAC). The inhibition mechanisms, studied from the aspect of surface hydrophobicity, surface charge, interlayer water content, and crystal spacing, can be concluded as that EDD reduces clay electronegativity and enhances the hydrophobicity of the clay surface, thereby keeping clay in a stable state. Compatibility tests showed that EDD can be used in guar based fracturing fluid. This study provides an alternative clay stabilizer for hydraulic fracturing.
危险品化学品经营许可证（带存储）