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Aiming at the problem of large friction in the process of drilling large-reach horizontal wells and the environmental protection requirements of drilling fluids, an environmentally friendly drilling fluid lubricant was developed based on amide reaction. The molecular structure of the new environmentally friendly lubricant was characterized by infrared spectroscopy and the thermal decomposition process of the environmentally friendly lubricant was tested by thermogravimetric analysis. The average particle size of the environmentally friendly lubricant was tested by particle size distribution experiments and the comprehensive performance of the environmentally friendly lubricant was evaluated through laboratory experiments. The test results show that the particle size D50 value of the new environmentally friendly lubricant is 387 nm, the particle size distribution is uniform and its lubrication The coefficient reduction rate is greater than 90%, the influence value on drilling fluid density is less than 0.003 g/cm³, no biological toxicity, EC50 value is 36000 mg/L, At 260 °C, the quality retention rate is 90%, the temperature resistance can reach 180 °C, and it can resist the pollution of 10% NaCl, 1% CaCl2 and 8% poor soil and maintain the reduction rate of the lubrication coefficient greater than 70%. The environmental protection lubricant can achieve 88.3% corrosion inhibition effect under the condition of 0.5% dosage. The environment-friendly lubricant has good compatibility with the polymer drilling fluid system and polysulfonate drilling fluid system under the condition of 1% dosage. The development of this environmentally friendly lubricant is of great significance for improving the ROP of complex wells and meeting the needs of on-site environmental protection technology. [ABSTRACT FROM AUTHOR]