Waste-free processing of waste nickel slags

Abstract

The paper considers one of possible options for the waste-free processing of dumped masses of nickel slags, accumulated over the years of operation of some enterprises. This process includes the use of hydroand pyrometallurgical processing, which results in three products: iron sulfate, ferrosilicon with a small admixture of aluminum, and slag from the ferrosilicon smelting. The slag has a hardness of 7-7.5 Mohs and can be used as an abrasive powder for sandblasting, or as a raw material for production of high alumina cement. The resulting iron sulfate can subsequently be purified from the copper, nickel, magnesium, and aluminum impurities and brought to the existing GOST compositional requirements. The resulting ferrosilicon, whose silicon content is similar to that of the marked ferrosilicon FS 75 with an aluminum admixture, can be used for deoxidation and silicon alloying of all existing grades of steels and cast irons. In this case, specifications drawn up with participation of a consumer enterprise can be a regulatory document for such ferrosilicon. The slag obtained during the ferrosilicon smelting can also be defined within the framework of these specifications for the abrasive powder producing enterprises.