Study and application of a new blockage remover in polymer injection wells

Abstract

With the extensive application of polymer flooding technology in offshore oilfields, the plugging in polymer injection wells has become more and more severe, which seriously affects the oil displacement effect and regular production of oilfields. In this paper, a new kind of blockage remover has been developed and evaluated by rheological behavior experiments, dissolution experiments and core flooding experiments. The results reveal that this new blockage remover can effectively reduce the viscosity of polymer and completely degrade the reservoir blockage with low corrosion rate. It is beneficial to long-term production of oil wells in offshore oilfield. Results of core flooding experiments show that this new blockage remover can relieve polymer damage and improve permeability. The agent has been applied in LD10-1 oilfield in 2016, the daily injection rate increased significantly after stimulation.

Keywords

Polymer injection wells / Formation plugging / Blockage remover / Performance evaluation / Field application

Acknowledgments

The work is Supported by National Science and Technology Major Project of the Ministry of Science and Technology of China “High Efficiency Oil Production and supporting Technology Demonstration on Bohai Oilfield” (No. 2016ZX05058-003).

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