Using on-stream X-ray fluorescence analysis to determine the chemical composition of drill cuttings

Abstract

Background. The authors investigate the problems arising from the lack of information on the chemical composition of the drilled rocks during the construction of a well. Aim. The aim of this study is to determine the possibilities and efficient application of the streaming XRF method for determining the elemental composition of unwashed drill cuttings. The contribution of the paper lies in the lack of experience in the world practice of using streaming XRF analyzers. Materials and methods. Furthermore, the authors evaluate the possibility to use the streaming XRF method for analyzing the chemical composition of drill cuttings for the development of the oil industry. At the same time, the application of the proposed method is justified. The basis of this study are the results of the application of the streaming XRF method using the CON-X 02 streaming spectrometer for analyzing the chemical composition of drill cuttings not washed from drilling mud. This project has been implemented according the technological project between Gazpromneft — NNGGF LLC in cooperation with Nosov Magnitogorsk State Technical University and Gazpromneft — STC LLC. Result. The article presents the results of determined main elements of the composition of drill cuttings. The authors have carried out the analysis of changes in the intensity of the characteristic lines of the main components from the sampling depth. Simultaneously, the authors show the possibilities to derive correlation curves for various elements characteristic of certain rocks in the geological section of a particular field. Moreover, the study reveals the identification and characteristics of geochemical signs of specific target layers. Conclusions. Based on the results of the study, authors may conclude that to obtain the correct results on the intensity of spectral lines of various chemical elements during streaming XRF analysis, there is no need to flush the cuttings from the drilling fluid. Finally, it is possible to qualitatively control the main elements of the composition of the drill cuttings.