渤海J油田注聚受益井堵塞物成因研究

Study on Causes of Plugs in Polymer Injection Beneficial Wells in Bohai J Oilfield

通过对现场注聚受益井堵塞物样品进行组分分析,配合XRD法、扫描电镜(SEM)/能谱法、红外光谱(IR)法、色谱(GPC)法多种表征手法,以及堵塞物动态模拟评价、长岩芯动态驱替实验研究了J油田注聚受益井堵塞原因。结果表明,堵塞物的无机成分为不配伍产生的垢、黏土矿物和铁盐沉淀,有机成分为三价金属离子交联产出聚合物形成的胶团;聚合物在酸性条件会与Al^3+、Fe^3+发生配位作用,生成聚合胶团水不溶物,且交联程度随浓度的增加而增强,加深储层伤害。

Reservoir stemming in polymer-injection wells in Bohai J oil field is analyzed by applying X-ray polycrystalline diffraction,scanning electron microscopy/spectroscopy,infra-red spectrometer,the dynamic simulation experiment,the dynamic displacement experiment of long core,and the stemming formation mechanism and its micro morphology are studied.The results show that the inorganic components of the blockage are fouling matter,clay mineral and iron salt precipitation.The organic component is micelle formed by crosslinking polymers produced by trivalent metal ions.The polymer will coordinate with Al^3+ and Fe^3+ under acidic conditions,generating water insoluble polymer micelle with cross-linked network structure,And the degree of crosslinking goes up with the increase of polymer concentration,deepening the reservoir damage.The research results can provide a basis for the study of the plugging removal working fluid system and the plugging removal scheme.