:: HGE Successfully Upgrades Concentrate Handling at Bulgarian Smelter

A flexible and trouble-free raw materials handling system for Umicore's recently modernized copper smelter at Pirdop in Bulgaria was needed to cope with the increased throughput. HGE was given the task to improve the current unloading, storage and feeding operation.

The copper concentrates had particularly demanding material flow characteristics due to their fine particle size and occasional high moisture content. HGE retained the services of Jenike & Johanson Ltd. (www.jenike.com) to measure the flow properties and provide functional design recommendations for reclaim hoppers and feeders. The test results showed these copper concentrates to be extremely cohesive and difficult to handle.

The project consisted of a new Railcar Unloading Building and associated equipment, a refurbished Bedding Plant, new mass flow hoppers and feeders in the Blending Plant, and new mass flow hoppers and feeders for the Dryer Feed Bins.

The project had to be performed in such a manner as to avoid interruptions to production. The design offered considerable installed redundancy, at minimal cost, by allowing both the Blending and Bedding Plants to feed the Dryer Feed Bins. These in turn feed the Flash Smelting Furnace via the dryers. Thus, if one feed source is out of service, the smelting process is not interrupted.

Under normal operating conditions, local concentrates are stored in the Blending Plant and imported concentrates in the refurbished Bedding Plant. However, the new system easily allows storage of imported concentrates in the Blending Plant and storage of local concentrates (or pre-blended mix) in the Bedding Plant. A high degree of flexibility has been achieved.