Methodology of controlling amino compounds and latex in drilling muds

Abstract

In industrial practice, rock hydration inhibitors, classified as amine compounds, are being increasingly used in drilling mud compositions. There is no methodology for determining this type of compounds content in the drilling mud, and proper servicing of this type of muds requires constant monitoring of their content to ensure appropriate inhibitory properties. During drilling, amine compounds adsorb on the surface of rocks and their concentration decreases during drilling and reduces the inhibitory properties of the mud. A common additive used in the composition of drilling muds is latex, the determination of which is necessary to ensure the mud parameters stability. Compounds of this type ensure the stability of the borehole wall, while their content also decreases during drilling. The results obtained from the research presented in the article allowed to propose methods for the determination of amine compounds and latexes. These methods can be used in the field laboratory when servicing drilling muds. The article presents the methodology for determining the content of new types of chemicals used in drilling muds, i.e. rock hydration inhibitors classified as amine compounds and latexes. The proposed methods enable proper servicing of muds with the addition of the agents that ensure the maintenance of appropriate mud properties. The method for the determination of amine compounds consists in determining the total nitrogen in the drilling mud filtrate. Dilution of the filtrate provides the results within the measuring range of the method and reduces the concentration of chloride ions, the amount of which may not exceed 10 000 mg/dm3. The first method of latex determination is weight determination of the dry residue after separation of the latex from the filtrate with acetone. The second one is based on nephelometric measurements of a tenfold diluted filtrate. The measurement result is the NTU (nephelometric turbidity unit) value depending on the latex content in the filtrate. All of the developed methods require the preparation of calibration curves, which are the basis for calculating the content of a given agent in the mud.