OCR

San Nicolas Iron Beneficiation Project The plant and ore handling facilities were built to upgrade the Marcona Mine iron ore prior to shipment all over the world. The plant is not only capable of upgrading the various types of ores, but also of producing numerous types of ore products. These facilities will contribute greatly to the future profitability of Marcona's operations. Beneficiation of the ore results in a more concentrated product, so that the value per ton is increased substantially. Not only does this increase the value of the ore and its saleability, but also decreases the shipping costs in relation to the value of the ore shipped. In addition, it is possible to utilize ores of lower grade which otherwise could not be marketed economically. The beneficiation process consists essentially of crushing, screening and grinding the ore and then separating the iron bearing portion from the rest of the ore. Since some of the ores are magnetic, magnetic separators can be utilized to separate the iron oxides from the waste material. For non-magnetic ores, separation is accomplished by utilizing the difference in weight between the ron-bearing particles and the other material. In this "heavy-media" separation process , the crushed ore is introduced into a heavy liquid which allows the iron par- ticles to settle to the bottom while the waste material floats and is removed from the surface of the liquid. After separation has been completed, the concentrated ore is de-watered and stockpiled or made into pellets prior to shipment. Before this facility all of the ore shipped from San Juan and San Nicolas had been high grade ore suitable for direct shipment. Two huge rod mills, which grind the ore for magnetic separation in the new Magnetic Concentrating Plant started operation in September, 1962. This was followed by further coarse and fine grinding lines. The completed plant is capable of producing numerous types of concentrated ore. These new mills were producing specification product and at designed rate of produc- tion within a few hours of startup and Marcona has expressed complete satisfaction. The program at San Nicolas was initiated on July 4, 1960. The contract between Marcona Mining Co. and Utah Construction & Mining Co., provided that Utah would handle complete engineering, procurement, and construction of all facilities under the general direction of the Marcona Technical Services Group. The long range program which was set up pro- vided for the design and construction of the new facilities in stages. The first three stages included a limited amount of ore beneficia- tion facilities, plus non-process facilities such as utilities, roads, buildings, and a diesel power plant to support the initial requirements of the new operation located some eight miles from the existing San Juan operation. Also included were a downhill conveyor system, a pier with associated pierhead facilities (including a shiploader), and product storage facilities.