Quality of rock from Ngrayong Formation as additional material for cement manufacture, Gunem District, Rembang Regency, Central Java

• Main Authors: Winarno, Tri, Marin, Jenian, Tiffany, Charlotte
• Format: Conference Proceeding
• Language: English
• Subjects: Aluminosilicates; Aluminum oxide; Aluminum silicates; Calcium carbonate; Cement; Chemical composition; Geochemistry; Limestone; Lithology; Portland cements; Quartz; Sandstone; Sedimentary rocks; Silicon dioxide; Siltstone; Sulfur trioxide
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/5.0061093

Due to development of infrastructure in some regions of Indonesia, existing cement producers are expanding their capacity and new investors began to build new factories as well. Portland cement is the most commonly produced cement in Rembang area, mainly using limestone (CaCO3) mixed with additional material clay, shale, sand as source of alumino-silicate. This study aims to evaluate quality of sedimentary rocks from Ngrayong Formation in Gunem District as additional material in cement industry. Detailed field mapping and rock sampling are used to determine lithology types of study area, supported by petrographic analysis. Geochemical XRF analysis aims to determine chemical composition of rock samples as standard parameter for material quality. Lithology of study area is sedimentary rocks composed of layers of quartz sandstone, siltstone, and claystone with slightly to completely weathered. This study uses company chemical standard SiO2 > 65%, Al2O3 > 16.5%, and SO3 < 2.5% for rocks. Result of geochemical concluded that quartz sandstone in the western part of study area and claystone meet the aforementioned standard as additional material for cement mixture. Other rocks are unsuitable as they can damage manufacturing equipment as well as compromise the final cement quality.