Abstract:
Due to the agricultural intensification in Sri Lanka, there is a high demand for potassium (K)-fertilizer inputs. However, in the Sri Lankan geological setting, the presence of major potash sources is minimum though the K- bearing minerals and rocks are abundant. Therefore, exploration of K-bearing mineral deposits is essential to cater the demand of K-fertilizer in the country. In this regard, this research is focused on investigating the K-bearing minerals and rocks in Sri Lankan geological terrain which can be used as K-fertilizers directly or as alternatives for currently available K-fertilizers. During sample collection, K-bearing minerals, such as feldspar and mica and K-bearing gneiss rock samples were collected from Matale, Kaikawala and Kadugannawa areas. Processed samples were subjected to analyse major oxide concentrations and K concentrations and surface topography. Analyses revealed that the highest actual potassium concentrations were presented in orthoclase feldspar (10.35 w/w%) and then biotite mica (9.95 w/w%) whereas other rocks showed the lowest. Based on the results, biotite mica (Kaikawala) and biotite gneiss (Matale) displayed the highest potential for K recovery, whilst the least potential for K recovery was shown in orthoclase feldspar (Kaikawala). However, further studies are recommended to develop this K-fertilizer and to assess whether its application is economically viable.
Citation:
Nivethithan, T., Ariyawansha, K. A. P. M., Dahlan, A. C. A., Abeysinghe, A. M. K. B., Ratnayake, N. P., Premasiri, H. M. R., Dushyantha, N. P., Batapola, N. M., Dilshara, R. M. P. (2022). Identification of potential minerals/rocks in Sri Lankan geological terrain as source of potassium (K) fertilizer. C. L. Jayawardena (Ed.), Proceedings of International Symposium on Earth Resources Management & Environment 2022 (pp. 43-48). Department of Earth Resources Engineering, University of Moratuwa. http://dl.lib.uom.lk/handle/123/19696