Study On The Properties Of New High Density Powder Weighting Agent

Drilling of abnormal high-pressure strata,deep wells and ultra-deep wells has become an important direction for the development of China's oil drilling industry in the future.From the actual application situation in the field,in order to overcome the rising formation pressure,the high-density drilling fluid technology has gradually evolved toward extreme technology,that is,the maintenance of drilling fluid density is not limited to “high”,but constantly in the direction of “ultra-high”,the contradiction between rheology and sedimentation stability is one of the main difficulties in high-density drilling fluid technology.High solids content can lead to a series of problems such as friction and torque is increased,hole cleaning difficultly,and difficult maintenanc of drilling fluid performance.Conventional weighting agents such as API barite have gradually become difficult to meet the performance requirements of high-density drilling fluids.In the application process,problems such as solid phase sedimentation and rheology are difficult to control,the development and application of new weighting materials have become a research hotspot in recent years.In this paper,the research on the properties of two new high-density micronised weighting agents,namely,micro-manganese and micronised ilmenite.Firstly,the physical and chemical properties of the new high-density micronised weighting agents are tested by electron microscopy,particle size analysis and potential testing.And the effect of its performance characteristics on drilling fluids was investigated.The effects of high-density drilling fluid rheology,sedimentation stability,lubricity and water-reducing wall building properties and its mechanism were studied through laboratory tests.The advantages and disadvantages of the new high-density micronised weighting agents and the traditional barite weighting agents were compared;the particle size grading calculation model of the new high-density micronised weighting agents and the traditional weighting agents is established,and the optimum ratio of the high-density micronised weighting agents and the API barite weighting agents in the high-density drilling fluid was evaluated.The effect of compounding high-density micronised weighting agents and API barite weighting agents in high-density drilling fluid was evaluated.It was found that the reasonable compounding ratio can combine the advantages of new high-density micronised weighting agents and the traditional weighting agents.Effectively improve the performance of the high density and ultra-high-density drilling fluids,and provide a reference for the application of new high-density micronised weighting agents.