Estudo de sistemas de colchões lavadores para aplicação em poços perfurados com fluidos de perfuração não aquosos

Abstract

Drilling fluids used to assist the operation of drilling perform several functions among them, forming a film of low permeability (filter-cake) in the walls of the borehole preventing damage to the formation. After the descent of the column casing, the annular space to be filled with cement during this process are used, often two types of mattresses, "cushion washer" and "cushion spacer", where the first aims at removing the filter-cake formed by the drilling fluid and the second avoid contamination of the cement by other fluids. The efficiency of the mattress scrubber is enhanced by the presence of mixtures of dispersants and surfactants in the composition. The use of technology is an alternative surfactant in removing the nonaqueous drilling fluid and has been demonstrated in field operations that these techniques are successful. Within this context, this work was carried out with two main objectives: to study the parameters that influence the microemulsion system (nature of the surfactant (T), the nature of the cosurfactant (C) and the C/T) and evaluating the removal efficiency of a movie drilling fluid synthetic paraffin base and brine (70:30). From the construction of the diagrams were chosen those with larger regions of microemulsions. The mattresses washers microemulsion formed with KMS surfactant, n-butanol and the ratio C/T 0,5 were those with the best efficiency results, on average 33 seconds according to the "PROCELAB". The results indicated that the mattresses microemulsion systems are promising vehicles contributing to the cementing operation of oil wells because they are of great interest and economical production that mattresses are performing well in their jobs.