The quantities of slag obtained world wide are increasing, which can lead to the removal of agricultural lands from the agricultural use and even to their pollution with various heavy metals. In accordance to statistical data, over 400 million tonnes of iron and steel slag are produced every year. Over the past 20 years, the recovery rate of these by-products from the steel industry has increased significantly. Innovative technological developments and the cooperation with other industries have brought the steel industry closer to reaching its Zero Waste goal. The slag obtained from the steel industry is a mixture of silica, calcium oxide, magnesium oxide and aluminium and iron oxides. Due to the characteristics of these secondary materials, respectively due to the high content of calcium oxide, they can be used on agricultural lands in order to neutralize the soil acidity and implicitly, for a better valorization of nutrients by the crop plants. Currently, the forecast given for the evolution of soils, both internationally and in our country, shows a continuous tendency of degradation of agricultural soils, agriculture being both a factor of degradation and a victim of the degradation caused by other socio-economic activities and also by agriculture itsel. In the last period, as a result of the application of agricultural technologies and due to the long-term fertilization with mineral Nitrogen fertilizers, a decrease in the soil’s reaction has been recorded. The efficient use of these by-products of the steel industry as an amendment in agriculture in order to neutralize the soil’s acidity, for improving crop productivity, for mitigating greenhouse gas emissions and for stabilizing heavy metals from contaminated soils, turns them into a value-added product in sustainable agriculture. This paper aims to present the influence of these materials resulted from the steel industry in improving the reaction of acidic soils, the influence they have on the main chemical properties of the soils and the influence on the production and quality of agricultural crops.

steel industry residue, steel slag, soil fertility, recycling, soil amendaments, acid soil

sciences soil

Presentation: poster