MINERALOGICAL AND GEOCHEMICAL PARTICULARITY OF DRILL CUTTINGS FROM OIL FIELDS ON THE EXAMPLE OF OBJECTS OF THE TOMSK REGION

Abstract

The relevance of the research is in poorly studied mineralogical, elemental composition and toxicity of drill cuttings formed during the construction of wells in oil fields. The main aim of the research is to identify the geochemical and mineralogical particularity of drill cuttings, to determine the toxicity of this type of waste using modern research methods. Methods: X-ray powder diffraction; inductively coupled plasma mass spectrometry; scanning electron microscope; bioassay. Results. Common minerals, such as quartz, albite, muscovite and calcite, were determined in the studied samples of drill cuttings that indicates a similar composition of the original host rocks. The geochemical specificity of drill cuttings expressed in increased concentration of chemical elements such as Pb, Zn, Cu, was revealed. Mainly, the elements belong to heavy metals of I, II and III hazard class. The value of the total pollution indicator shows that most samples of drill cuttings are of low pollution. However, the samples from existing sludge pits are characterized by medium pollution. The identified mineral phases are represented by oxides of iron, lead, zinc, iron sulfide, barium sulfate. Spherical particles of iron and lead were discovered. In general, drill cuttings samples have not toxic effects on test objects: Daphia magna, Scenedesmus quadricauda, Drosophila melanogaster. At the same time, samples from existing sludge pits have an effect on the test organism Daphia magna. In this way, the studied samples of drill cuttings are low-hazardous, practically non-hazardous waste, and are not potentially toxic.

Keywords

• drill cuttings
• sludge pit
• well pad
• oil field
• elemental composition
• heavy metals
• bioassay