Development and Application of The Graft Coated Viscosity Reducer

Abstract

The graft coated viscosity reducer was developed for the high cost of mixing light oil. The viscosity reducing mechanism is that the polar hypertonic agents in thSe viscosity reducer dissociate the net structures of the resin and asphalt and then form eutectic grafting with these dissociated macromolecules when the heavy oil in the water was broken or in the solution of associating state. The heavy oil takes shape of small particles while the resin is out of structure and not easy to get agglomerated. The released resin and the coating agent for the viscosity reducer form a layer of film on the surface of small oil particles to prevent the resin and asphalt from network structuring again. The heavy oil particles are not easy to be in coalescence concerning electrical repulsion and solution association among the coating in between. The heavy oil particles are dispersed in the medium to achieve the stabilization of viscosity reduction. For example, the viscosity of the crude oil from Liaohe Oilfield is 87.2mP•s after adding the agent at 50°C (the original viscosity was 4919mP•s). The viscosity reducer did not corrode the pipelines and wellbores and had no effect on the dehydration of united stations. The construction was carried out by continuously dripping the viscosity reducer into the 16 wells of Liaohe Oilfield. The viscosity all decreased to below 100mP•s afterwards. The current, load and other parameters all decreased along with the application. So this method could take the place of mixing light oil.