There are many types of scrap copper, and the recycling technology and processes are also different, but they are generally divided into two parts: pretreatment and recycling. The so-called pretreatment is to classify the mixed scrap copper, select other waste materials mixed with machinery, remove the oil stains on the surface of the scrap copper, etc., and finally obtain a single variety of relatively pure scrap copper, which provides excellent raw materials for smelting, thereby simplifying the smelting process. There are many methods for recycling scrap copper, which can be mainly divided into two categories, namely direct utilization and indirect utilization of scrap copper. Direct utilization is to directly smelt high-quality scrap copper into refined copper or copper alloy, and indirect utilization is to remove the base metals in the scrap copper through smelting, cast it into anode plates, and then electrolyze it to obtain electrolytic copper.
The pretreatment part of this article will focus on the pretreatment technology of scrap copper wires and cables, and the recycling part will focus on the processes and patents of some foreign recycled copper plants.
(I) Pretreatment of waste wires and cables
The purpose of pretreatment of waste wires and cables is to separate the copper wire and the insulation layer. There are four main methods:
1. Mechanical separation method, which can be divided into two types.
(1) Drum stripping machine processing method. This method is suitable for processing waste wires and cables of the same diameter. my country already has such equipment. The Wolfe Hampton plant in the UK uses this equipment to strip waste wires and cables with good results.
The waste wires and cables are first cut into segments with a length of no more than 300 mm, and then manually fed into a special drum shredder. In the drum shredder, the wires and cables are broken and peeled, and the debris leaks out from the 5 mm diameter sieve hole at the bottom of the drum blade. The drum speed is 3000 rpm and the drum diameter is 200 mm.