Recently, some customers confirmed with us whether we can guarantee that there is no metal components mixed during carbon black particle processing line. Their raw material is tire pyrolysis carbon black. The reason why they want to remove metal component is that customs will do metal inspection for importer.
We all know that detection index for carbon black excludes metal detection. Carbon black produced from waste tire pyrolysis contain metal component itself. Today, we will make use of the topic to analyze all production circles which may lead to metal components in carbon black. Then, discuss how to separate metal contents.
First, in terms of raw material, before pyrolysis, waste tire will be shredded first. Existing pyrolysis process mainly consists of large block furnace entrance pyrolysis and rubber ball furnace entrance pyrolysis. For former method, iron wire always mix into carbon black. What’s more, it is also hard to prevent oxidized iron sheet from entering carbon black. These are internal influence element of raw material.
Second, grinding procedure. No matter horizontal crusher, vertical crusher or vibrating ball mill, all these machines rely on metal components to contact and function with carbon black. There will definitely be metal loss during the process. In addition, if raw materials are mixed with metal components which are not separated out before entering crusher, metal may mostly likely be crushed into fine powder and increase bulk density of product.
Third, pelleting/granulating circle. Carbon black granulator/pelleting machine adopt stainless steel lining drum and alloy pin mixing head which also will be continuously consumed and cause metal content in product.
Fourth, carbon black particle drying procedure. Carbon black will rub with rotary dryer drum, which may also increase iron content of product.
Combined with above reasons, on the premise of not adding and amend equipment process, only do adjustment to raw materials. Avoid entrance of metal components. If customer want to solve this issue completely, there is only one method that is to communicate with buyer and sell ultra-fine powder. Before packing, separate out metal content. This metal content is not only simple magnetic substance and cannot be simply removed by magnetic separation. Therefore, customer must choose eddy current and air separator for specific gravity separation.