Зарубіжний досвід утворення та використання доменних шлаків

Abstract

We should regard an issue of efficient use of feedstock and, in particular, a transition to waste-free technology from the perspective of adjusting differences between economic growth (more resources in production required) and “productive capacity” of the environment (depletion of mineral resources, lowering of resources quality, disruption of environment balance). It is possible to adjust these differences not only by using resources rationally and comprehensively but also by processing generated industrial waste. In the Ukrainian metallurgical industry, these issues are very important because of the abundant practice of use of out-of-date resource and energy-intensive technologies and feedstock of poor quality. International experience shows that the metallurgical industry has rich potential in reducing generated waste. On average specific solid waste generation for a unit of product in the metallurgical industry in developed countries is 1.5-3 times lower than in Ukraine. One of the important processes of blast-furnace performance is the generation of slag; slag is one of the most valuable secondary materials. Recently international metallurgical enterprises started implementing a hundred percent recycling of use industrial waste. Moreover, for the past decade there were a lot of efforts made to process slag so to meet strict EU environmental requirements, hence we can regard it not as waste but as an industrial by-product. We use slag mainly in the road sector – for road construction, agriculture ‒ for liming of soils, metal industry – as an iron-containing substance for secondary melting in blast furnaces. The cement industry is the main consumer of blast furnace slag. EU regulations allow up to 35% of granulated blast furnace slag in Portland cement and up to 80% in Portland blast-furnace cement. The addition of blast furnace slag into the mixture increases the performance of blast furnaces and reduces fuel consumption by 15% and prime cost by 25-30 %. Apart from that the slag as an additive considerably improves several construction and technical peculiarities of cement. International experience and expert assessments say that Ukraine has not only huge potential in reducing blast furnace slag generation but also a need for its comprehensive processing with up-to-date technologies and state-of-the-art equipment that can bring an economic and environmental advantage.