Modelling acid attack of oilwell cement exposed to carbonated brine. (January 2018)

• Record Type: Journal Article
• Authors: Liaudat, Joaquín; Martínez, Ariadna; López, Carlos M.; Carol, Ignacio
• Is Part Of: International journal of greenhouse gas control. Volume 68(2018)
• Page Start: 191
• Page End: 202
• Publication Date: 2018-01
• Subjects: Carbonation -- Carbon sequestration -- Well cement -- CO2 -- Carbonic acid -- Chemical model -- Finite Element Method; Greenhouse gases -- Environmental aspects -- Periodicals; Air -- Purification -- Technological innovations -- Periodicals; Gaz à effet de serre -- Périodiques; Gaz à effet de serre -- Réduction -- Périodiques; Air -- Purification -- Technological innovations; Greenhouse gases -- Environmental aspects; Periodicals; 363.73874605
• DOI: 10.1016/j.ijggc.2017.11.015
• Languages: English
• ISSNs: 1750-5836

Abstract

Graphical abstract: Highlights: A model for the carbonation process of oilwell cement exposed to carbonated brine. Formulation as simple as possible, but including key features. The model has been benchmarked against laboratory experiments. The model reproduces both qualitative and quantitative experimental results. Abstract: A diffusion-reaction model for the carbonation process of oilwell cement exposed to carbonated brine under CO2 geological storage conditions is presented. The formulation consists of two main diffusion/reaction field equations for the concentrations of aqueous calcium and carbon species in the pore solution of the hardened cement paste, complemented by two diffusion-only field equations for chloride and alkalis concentrations, and by a number of chemical kinetics and chemical equilibrium equations. The volume fraction distribution of the solid constituents of the hardened cement paste and the reaction products evolve with the progress of the reaction, determining the diffusivity properties of the material. The model is used to simulate experimental tests performed by Duguid and Scherer (2010), leading to promising results indicating that the fundamental aspects of the phenomenon are captured.