Project summary

Waste of steel manufacture (dust and sludge) is sintered and conveyed to the revolving hearth furnace (RHF), where it’s heated at high-temperature atmosphere thus acidized iron is regenerated and turned out to be the iron of direct regeneration (DRI).

The regeneration reaction is finished in 15 minutes due to the radial heat exchange and quick reaction of small fractions.

The DRI includes steel iron, some amount of zinc plumb and alkali iron from 605 till 85%, that’s way it’s a good addition in the process of cast iron and steel production.

The DRI consumers can be both blast furnaces and other smelting aggregates, such as electric arc furnaces.

Technical aspects of the project

Technology of waste (including iron) utilization implementation has to provide reliable and highly effective, ecologically save methods of sludge treatment – dangerous waste of steel production and to assist to the substitution of natural resources (iron ore) usage as iron. As a result the project activity leads to the reduction of dangerous resources emission and assists to carbon usage in the process of regeneration, which is a component of waste.

The main technical indexes

The main characteristics of revolving hearth furnace (RHF), installed at Kimitsu Works enterprise in Japan, are pointed in the table below.

Project efficiency

• The project aims to solve problems of dangerous waste utilization, which contain such admixtures as zinc, plumb, natrium, potassium, chlorine and others, besides dust and sludge on the basis of RHF from DRI receiving.
• The received DRI grains can be used at the enterprises as the raw-material for blast furnace production, which gives the possibility to save fuel – usage of 1kg of DRI in blast furnace for 1 t of cast iron economize to 0,23 kg of coke.

Project socio-economic consequences

The project implementation will have the raw of socio-economic consequences for the enterprise and region, such as:

• has the demonstrative effect, because in Ukraine implementation of the facilities for dust and sludge utilization (industrial technology) will be used firstly;
• leads to the improvement of ecological climate in the region due liquidation of sludge accumulator;
• leads to reduction of harmful substances to the atmosphere and to surface ornamental water, according to the reduction of payments for environment pollution;
• regeneration of not utilized resources and treatment of iron, plumb, zinc waste and others;
• increases the terms of usage of the industrial waste polygon;
• improvement of the cast iron production process – productivity increase and reduction of coke consumption in the way of DRI usage at the blast furnace.

Propositions concerning the technology of waste (including iron in RHF) utilization implementation were also suggested and learnt during visiting of OJSC "Zaporijstal" and OJSC "MSW named after Illich".