大牛地气田镶嵌屏蔽钻井液技术

Inlay-shield Drilling Fluid Technology in Daniudi Gasfield

大牛地气田开发区环保压力日益增加,应用成熟的钾铵基聚合物钻井液体系已无法满足钻井环保要求。镶嵌屏蔽钻井液体系包被颗粒呈网状凝胶态,通过瞬时高失水迅速在井壁建立刚性屏蔽膜,有效隔离钻井液对地层伤害,并显著提高封堵性,有效防止坍塌掉块;通过静电力和拖曳力,在钻屑表面发生多点吸附,形成隔离膜,抑制钻屑水化分散。现场应用表明,该钻井液体系可有效降低钻井过程地层漏失及井壁失稳的发生,可大幅减少现场固、液排放量,全程无废弃液落地,完井剩余液全部转下口井使用。实现了钻井过程的"零污染",能满足钻井对环保的要求,具有广阔的应用前景。

More attention has been drawn to the environmental protection pressure in Daniudi Gasfield,and the potassium amino polymer drilling fluid system cannot meet the environmental protection requirements. A rigid shielding film on the sidewall can be rapidly created through instantaneous high water-loss of the network-gel coated-particles in Inlay-shield drilling fluid system.This film can effectively prevent the formation damage from drilling fluid,significantly improve plugging efficiency and efficiently avoid Coated-particles collapsing and breaking. Multi-point adsorption and a shielding film are created by static electricity and drag force,which can inhibit cutting hydration dispersion. Field application shows that this drilling fluid system can effectively reduce formation leakage and improve wellbore stability and significantly reduce field solid and liquid discharge amount. There is no waste liquid on the ground in the whole drilling operation,and all remaining liquid of completion can be recycled in the next drilling operation. 'Zero-pollution'is achieved during the drilling operation,which can fulfill the environmental protection requirements and will obtain a broad application prospect.