Bong

BONG (EN: Bong; RU: Бонг) is the iron ore combined enterprise on the base of the Bong Range deposit of the iron ores within Liberia, the Salala district. It belongs to the "Bong Mining" firm, which is the joint enterprise of 4 metallurgical firms within the West Germany, and one Italian firm. It includes the open pit mine, beneficiation plant, 2 pelletizing plants, railway (the length is 66 kilometres, to the port of the Monrovia city), port built structures, auxiliary workshops, and so on. The extraction of the ore has been started during the 1965.

The iron ores of the deposit, which is being developed by the combined enterprise, are confined to the narrow synclines (the length is up to 12 kilometres), which are formed by the rocks of the Archean age (micaceous and amphibolic schists, gneisses). The ores are itabiritic, magnetite-hematitic (the ratio is 2:1), the content of Fe is from 37-46% (the zone of weathering, and the intermediate zone) to 30-40% (the magnetitic zone). The reserves of the ore (the average content of Fe is 38.7%) is 350 million tonnes (1977). The development of this deposit is conducted by the opencast method with the usage of the drilling-blasting works. The excavation works are performed by the power shovel excavators; the transport is the heavy-load dump trucks. Before the beneficiation, they average the ore by stowing it into 2 stacks with 250 thousand tonnes each, with the usage of the stacking machine (the productive capacity is 3 thousand tonnes per hour). They deliver by the bucket-wheel excavators the ore from the stacks into the beneficiation plant. The concentrate is subjected to agglomeration by sintering (the content of Fe is 64.5%), and pelletizing (after the addition of bentonite), within the drum pelletizers and roasting machines. The productive capacity of the plant is 2.7 million tonnes of concentrate for agglomeration, and 7.5 million tonnes of pellets per year.