Research And Application Of Water Basing Paraffin Removing/Inhibiting Agent

The productions of most oil fields have been in the middle-last development time in China, and accordingly the oil well produced liquid has been in the high water content period. Just because of this, the popular and widely used oil soluble paraffin removing/ inhibiting agent could not achieve the expected effect due to its low density. Aiming at this problem, a new water basing paraffin removing/inhibiting agent is developed for downhole use in high water cut oil wells in this study.The mechanisms of the water basing paraffin removing/inhibiting agent were as the followings:Firstly, surfactants with high permeability and strong dispersibility could assist the agent infiltrating into the gap of paraffin crystal with loose structure, thereby decreased the surface tension of paraffin. Secondly, the molecules of surfactants could permeate through paraffin, which decreased the binding force among paraffin molecules and destroyed the adhesion between paraffin and tube wall, therefore paraffin crystals were disassembled and flowed out of oil well with liquid fluid. Finally, surfactants were easily absorbed on the surface of metal, which reversed the surface of paraffin deposit to its hydrophilic surface, correspondingly prevented the adsorption and precipitation of non-polar paraffin crystal on metal surface and decreased the adhesion between paraffin with tube wall, consequently attained the paraffin removing/inhibiting aim.In present study, the water basing paraffin removing/inhibiting agent was synthesized by using water as dispersing media adding surfactants with different functions, cosolvents, stabilizers, alkali, etc. It could not only remove and inhibit paraffin, but also reduce crud oil viscosity and improve the flow ability. Furthermore, the lower the temperature was the lower crud oil viscosity by adding the water basing paraffin removing /inhibiting agent. The results showed that the percent of paraffin inhibition was 47.8%, which was much higher than 15%specified by industry standard of SY/T 6300-1997 "General Specification for Paraffin Removing/Inhibiting Agent in Oil Production".The present study analyzed the influence of water content in crud oil, formation temperature and the agent application dosage on the wax control effect of water basing paraffin removing/inhibiting agent, and pointed out the possible operating conditions and scope of the agent.