The Development Of Rheology Modifier For Biomass-based Drilling Fluids

Domestic oil-based drilling fluids for horizontal wells generally have problems such as low shear force,poor rheology,and difficulty in subsequent processing of cuttings.They need to be improved in terms of performance and environmental protection.In order to meet the development needs of green high-performance drilling fluids,biomass synthetic-based drilling fluids have come out.Because their viscosity is lower than that of oil-based drilling fluids,it is difficult for the existing rheology modifiers to achieve satisfactory lifting effects.In response to this problem,the research and development of rheology modifiers for biomass-based drilling fluids were carried out in order to increase the dynamic shear force and low shear rate viscosity and enhance the suspension of the system when the drilling fluid viscosity is less affected.Debris and wellbore cleaning ability.First,starting from the rheology experiment of commonly used rheology modifiers,it is optimized among six rheology modifiers of HIRHEO,BT,RM-60,PAC-50,MOSHT and BZDRM.Studying their way of acting on water-in-oil emulsions,it was found that the introduction of strong polar groups on the complex long carbon chain framework can greatly increase the shear force when the viscosity of the drilling fluid is relatively small.Secondly,starting from the molecular structure design of rheology modifiers,amide was selected as the basic skeleton,polyaniline was introduced,and four rheology modifiers were developed.A series of rheological evaluation experiments were carried out to determine the best synthesis method.The dimer acid and diethanolamine were mixed in a molar ratio of 1:2.1,polyaniline was introduced on it,and reacted at170-180? for 6 hours to develop a flow Type regulator AD-4.Finally,a biomass synthesis-based drilling fluid system was constructed,and the rheology modifier AD-4 was added to evaluate the system's resistance to temperature,pollution,aggravation,and environmental protection.The evaluation results show that the biomass synthesis-based drilling fluid system with the addition of rheology modifier AD-4 has good rheology,stable emulsion,high temperature resistance,strong anti-pollution ability,and environmental protection and easy degradation.