ORALS

The present study describes a zero discharge hydrometallurgical process for value addition of non-metallic LD Slag fines to multiple products of industrial importance. The process involves the quantitative separation and conversion of calcium along with some key nutrient elements which are part of LD Slag fines. This includes magnesium, iron, phosphorus, and manganese, which are used to form a new chemical compound viz Limegyp (Registered trade mark product) which finds application in the field of agriculture as a multi-nutrient soil conditioner. At the same time, the authors have also converted calcium into an insoluble anhydrite containing silica. The significance of the process lies in producing two types of products at the same time. One of the advantages of the process is that there is no generation of any type of gas or liquid pollutants. Hence it is strictly a zero discharge process which has enormous significance in the current global scenario. Another advantage of the process is that it reduces the recycling of LD Slag fines into iron making, thus limiting the entry of elements like phosphorus, alumina etc., in the steel making process. This innovative process is applied for patent vide Indian patent application No: P||1077||4||2019[1]. The present study further describes chemical and mineralogical characterization by different techniques such as ICP-OES Analysis, XRD, FTIR and Raman study.

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