Study On Interaction Of PSSMA Polymer With Montorillonite And Fluid Loss Mechanism

With the ongoing exploration of oil,the proportion of deep zone oil and gas reserves in the energy is becoming larger and larger. In order to solve the energy shortage, and to meet our energy needs, efficient exploration and exploitation of resources of deep zone oil and gas is showing its increasingly important position. Drilling fluid as "blood" of the drilling, its stability and fluid loss performance in the harsh conditions of high temperature and high salinity has become the key issues in the exploitation of deep zone oil and gas resources.This thesis is mainly focused on the interaction between styrene sulfonic acid-maleic anhydride copolymer PSSMA and montmorillonite and its effects on the dispersion stability of montmorillonite, with the characterization methods of colloid chemistry. And based on the harsh envirment faced by the the exploitation of deep zone oil and gas resources, the change of the physical and chemical properties of the polymer molecules in solution and its effect on the fluid loss of drilling fluid in the conditions of high temperature and high salinity was studied.The main content of the thesis includes the following parts:i) The effect of concentration of styrene sulfonic acid-maleic anhydride copolymer PSSMA on the colloid stability of montmorillonite dispersion was studied,and the mechanism is postulated to explain the phenomenon.ii) The comparative study of adsorption on montmorillonite particles and the Zeta potential of montmorillonite particles between different molecular structure of styrene sulfonic acid-maleic anhydride copolymer PSSMA is made,and the adsorption mechanism on montmorillonite is further studied by infrared spectroscopy.iii) The properties of risisting high temperature,high salt and foaming of three sulfonated polymer PSS,PSSMA(SS:MA=1:1),PSSMA(SS:MA=3:1) in the solution of NaCl and CaCl2was studied, focusing on the effect of monovalent and multivalent salt on solubility of polymer,and have a further discussion about relationship between polymer solubility and foaming property of solution.iv) The effect of configurational changes of the polymer molecules on the mud fluid loss of performance is investigated,we have a analyses on fluid loss mechanism and found that collapse,aggregation and even precipitation of polymer molecule chain can also have the ability of reducing filter loss.