On modeling the dissolution of sedimentary rocks in acidic environments. An overview of selected mathematical methods with presentation of a case study

Different environmental processes utilize calcium carbonate and sedimentary rocks, for instance sedimentary rocks are used for water purification as filters and utilized also for acid remediation of process waters before being discarded. Additionally sedimentary rocks are used in another very important environmental process, wet Flue Gas Desulfurization. In this process, limestone and carbonates in general play one important role because of their dissolution and provision of the necessary amount of calcium ions used for the precipitation of gypsum. The objective of this study is to present in a first place an overview of a reduced number of specific theoretical and empirical mathematical models applied to the dissolution of carbonates in acidic environments with provision of additional developments and details, secondly a case study was presented where a suitable time of exposure and surface diffusivity obtained analytically by different methods well describe the experimental results. There were justifications for this choice. The experimental data and the related mathematical modeling were performed considering transient conditions. In the present work diverse raw materials were tested in order to reveal their suitability for wet Flue Gas Desulfurization. The research was focused on products from  CO 2 fixation processes materials as well as other types of limestone samples. In this way it was found that also waste materials from different environmental processes, like  CO 2 fixation can be used for Flue Gas Desulfurization.