Techno-economic analysis of scenarios to develop the extraction of limestone for the southern area of Santiago deposit located in Estepa- Spain

Abstract

The lime is a versatile product with multiple applications in everyday life. According to the European lime association, each citizen uses around 150 grams of lime per day. It is used as a base material to produce various products in environmental, agriculture, metallurgical production, construction, and chemical industries, among others. The high range of lime applications generates many limitations based on the content criteria set by the consumers and varies according to the requirement and further use of the lime. According to the European lime association (2017), one of the highest lime uses is on steel production; 40% of the total world production is sold to the steel industry each year. The quality requirements for the lime to be used to produce steel are strict, setting the target for the obtention of lime with a high concentration of CaO and low presence of prejudicial impurities such as phosphorus or sulfur. Calgov lime production plant is located in the south of Spain. It supplies local and national consumers of lime and has been operating for approximately 35 years. The steel manufacturing industry is one of the major clients of the plant consuming about 50% of the total installed capacity. This industry's quality requirements are a significant concern for the plant, and the obtention of limestone with low phosphorus content one of the primary targets for the company's future. Currently, the plant is under high pressure to find and extract limestone with low content of P2O5, below 0.039%, which is the limit set by the client. Seeking to comply with quality and quantity, the plant has performed exploratory work in the southern area of the deposit in which resources of limestone that meet this target are found. In this work, a mine design and scheduling options for the extraction of the south area of Calgov deposit extraction is presented based on the composition requirements set for the limestone. Furthermore, a techno-economic analysis of the extraction scenarios is developed exploring different alternatives to deal with the lack of information about some areas of the deposit and alternatives to ensure a constant feed of lime to the plant, avoid over costs and increase the possible economic return.