Seventy percent of copper in MSB Bor came from Krivelj open mine and technical director of Mining basin Bor company MBB, Vidoje Adamovic, expects even better results by the end of the year from the accession to the richer classes and just completed the automation of the local flotation. – “Krivelj” has enough uncovered ore, but planned removal of tailings are still half. – “Cerovo” already processed 7,000 tons of ore per day, which is a good indicator. – Stabilized production of bulk lime in Zagradje
For six months of this year in the Bor copper mines has been excavated 90 percent of the planned amount of ore. 13,500 tons of copper in concentrate will be delivered to the smelter, which is 85 percent compared to the plan, while the semi-annual balances of stripping is partial. However, by the end of the year it is expected realization of close to 90 percent, as technical director of MBB Vidoje Adamovic announces the creation of conditions for the removal of two million tons of tailings per month. It must be, he said, respected the mining project of digging by 2031st and we should not allow serious disruption of ores and tailings relations.
-We are expecting end of June in MBB with about 2,400 tons of copper in concentrate, which will be about 90 percent of realization of the plan – says Adamovic. – At this moment let me loud Mine “Veliki Krivelj” who carries this production because over 70 percent of that copper comes from the open pit. Production at the largest mine is stable, with enough uncovered ore of good content, although smaller amounts that are unfavorable to the flotation are taken from the upper floors. Because of them, copper recovery is around 80 percent, but I hope that in the future will be better because digging leads into the wealthy. As in Krivelj flotation these days has been completed the full automation of the process, also on that side we expect progress. Technological process will be monitored and run through the electronics and set parameters and thus subjective assessment and omissions will be eliminated. Adamovic emphasizes that MBB respects the requirements of the new smelting technology and delivers a concentrate with over 20 percent of copper. It tries to put moisture in it below 10 percent. These days arrive so called flocculants just for this purpose.
-We will provide about 70 percent of tailings in June in relation to the plan – estimated our interlocutor five days before the end of the month. – The reason for this is the work of the transport system and interruptions due to slipping material around trays (height delay is over 350 meters) and the need to frequently move the tray to be safe. All this has hampered the achievement of a given capacity. However, in late June, as we announced, we are moving one of the excavator on the east margin of the open pit and begin removing of large quantities of overburden. This procedure is close to the new landfill, relations are short; to the end of the year I expect over two million tons of tailings per month and the realization of the plan in the stripping of the ninety percent. There were some problems with the trucks, the number of active fell from 16 to 13, but at the beginning of July, I expect them to finally be 18. I must say that, with all the difficulties that accompany us, the employees contribute a lot to keep pace. They realize that only with work we can positively operate, namely to settle all obligations and to have money for salaries. I expect stable mining in “Krivelj” until the end of the year.
In the “Cerovo” has been also doing better. Capacity of ore processing were increased and it goes over 7,000 tons per day. – I hope we can keep it in the coming period because at the local mine has been opened enough ore, soon the fourth truck will be included, and with two excavators, a bulldozer and drill we have a stable dug system in the ore. The problem with the sectional feeder on the primary crusher was solved, and by inserting new lining and some other procedures we have increased the capacity of flotation processing – says our source.
Although there are still many problems Jama has also stepped up deliveries of richer ore in recent days. Scattered ore bodies mean large engagement of transport and loading mechanization to achieve the planned objectives. Therefore it was started the procurement procedures of a jaw crusher that would facilitate the work underground. – The ore would be no longer climbed to the existing crusher – explains Adamovic – but it will descend towards the new, which would be on the horizon 19th. This would increase transport capacity and reduce hiring equipment, and it would create the conditions for entry the so called cap of the “Bor River”. And the flotation works better. Its “C” section processes all ore from Jama without a problem, and “B”, at which is built a vertical mill, slag from the new smelter. The parameters given for a new slag in the project – are respected.
With the opening of one of the two “Auerbach” furnaces in Zagradje also has been stabilized the production of bulk lime. According to Adamovic, more than 150 tons are already produced per day, which meets the needs of MBB. Intensively the overhaul of another furnace like that also has been started and plan is to put it into operation by August 6th. – With it the quantities of bulk lime crossed over 220 tons per day, which would meet the needs of Majdanpek flotation. This means that MSB would no longer have the need to procure lime on the side. The lime from Zagradje is of satisfactory quality (activity over 80 percent), so we can expect good input parameters in the process of flotation.
Interventions on Krivelj tailings
From the technical director of the Copper Mine Bor, we found out that the “zero” field of Krivelj tailings (it will be upstream along the Krivelj’s river, towards the mine)has been considerably projected due to the fact that the capacity of “two fields” is exhausted, and “field one” is at the end. Adamovic announces that in the next three months, by its own forces, should be also completed the rehabilitation of collectors under Krivelj tailings. Testing has shown that it is not in critical condition, however, MBB is obligated to, as soon as drops the level of the Krivelj’s River, to replace reinforcement in the form of metal rings, so-called belt, that have yielded. The contracting of acacia seedlings, by which would be reforested second and third dam in autumn, is underway, and in the meantime will begin earth hauling, creating a terrace for their planting and preparing the system for watering of these plants
