The article covers the history and methods of developing and improving Vietsovpetro drilling mud systems, applied for drilling the production and exploration wells. One of the major ways to improve technological and economic efficiency of well construction is to apply high-quality drill mud systems with such properties, which comply the geological conditions of drilling and low costs. Having the corresponding laboratory base at Vietsovpetro disposal, the specialists of the company develop and improve drill mud systems, which conform the geological conditions of Vietsovpetro fields and current requirements on cleaning the wellbore from the cuttings, as well as allowing implementing the modern rotary steerable systems. The improved biopolymer drilling mud systems have been developed from a simple recipe of inhibitive aluminum-potassic mud (IAPM).
The improvement of recipes has been performed by Vietsovpetro specialists own resources with studying contemporary materials, chemicals and performing the significant amount of laboratory tests.
To increase inhibitive and lubricating properties, the IAPM system has been improved by adding such inhibitors, which under a high temperature, generate the emulsion at the bottomhole, helping inhibiting clay shales and reducing the drill tools torque. Further improvement of the mud system included implementation of anionic polymer. Its objective is to inhibit clays and encapsulate solid particles of drilled cuttings. To stabilize pH and improve efficiency of lubricating additives, the alums had been removed from the recipe while polyalkylene glycol was substituted with polyethylene glycol, which is effective under high temperatures above 80 °C at the bottomhole. The next stage of improving Vietsovpetro drill muds was application of advanced BASF agents in the recipes. Following the successful lab tests, the pilot tests of such recipes are planned.
The developed recipes containing the advanced chemicals, have high indicators of inhibiting ability, thermal stability and PH stability, and on top of that, may compete with high-quality muds of service companies, but differ by lower costs.
References
1. Ryazanov Ya.A., Entsiklopediya po burovym rastvoram (Encyclopedia of drilling mud), Orenburg: Letopis' Publ., 2005, 664 p.
2. Nasiri A.R., Valizadeh M., Norouzi H., Hemmati M., Investigating the effect of Polythin and Polydrill on the properties of drilling fluids, Journal of Petroleum Science and Technology, 2012, V. 2, no. 1, pp. 37–42.
