A Feasibility Study on the Application of Basic Oxygen Furnace (BOF) Steel Slag for Railway Ballast Material

Abstract

Railway ballast, for which natural crushed stone aggregates have been generally used, is an essential track component for the distribution of train loads along the rails and sleepers to the roadbed. However, the use of natural crushed stone aggregate causes environmental destruction as well as dust production in train service. This paper evaluates the feasibility of using the basic oxygen furnace (BOF) steel slag as railway ballast material. A series of physical and chemical quality tests are performed to investigate the characteristics of the materials associated with the effect of aging period due to the remaining free CaO and MgO in the BOF steel slag. Three different aging periods (i.e., 0, 3, and 6 months) are used to compare with various standards and the properties of the crushed stone aggregates. It is demonstrated that the physical and chemical properties of the BOF steel slag with different aging periods satisfy all requirements of standards sufficiently. Especially, the BOF steel slag without aging (i.e., 0 month) provides the similar physical and chemical properties, when compared to the BOF steel slag with aging (i.e., 3 and 6 months). Thus, it is possible to apply the BOF steel slag regardless of aging periods to the railway ballast materials instead of natural crushed stone aggregates.

Mechanical Properties of Coal Ash Particle-Reinforced Recycled Plastic-Based Composites for Sustainable Railway Sleepers

“…In addition, the slag aggregate is a byproduct of steelmaking generated during the refining process and can be classified as basic oxygen furnace (BOF) slag, which was supplied by Yujin Ecociel Co., Dangjin, Korea. Detailed information of the slag aggregate can be found in Koh et al [ 23 ] and Tafesse et al [ 24 ]. Figure 3 shows the fillers used.…”

An Experimental Investigation on the Fill Properties of Industrial By-Products Generated in Turkey

“…Son yıllarda sürdürülen araştırmaların çoğu EAF çelik cürufunun kullanılmasına yoğunlaşsa da BOF çelik cürufu çıktısı ülkemizdeki toplam çelik cürufu çıktısının hala önemli bir bölümünü oluşturmaktadır [34]. Son yıllarda BOF çelik cürufunun geri kazanımıyla ilgili yapılan uluslararası çalışmalar arasında malzemenin demiryolu balastı olarak kullanılması ve açık gradasyonlu agrega olarak asfalt karışımlarında kullanımı da vardır [43,44]. BOF çelik cürufunun faydalı kullanımını kısıtlayan en önemli özelliği su varlığında hacimsel genleşme olduğu için yürütülen araştırmaların çoğu malzemenin genellikle çakıl boyutundaki kısmının kullanılmasına yöneliktir ve kum boyutundaki malzemenin dolgu olarak kullanılması ile ilgili yapılan çalışmalar oldukça sınırlıdır [30].…”

Classification of BOF Slag by Data Mining Techniques According to Chemical Composition

“…Due to the vast research performed with the aim to valorize slag, it is interesting to obtain a relationship between potential applications and slag clusters [18,19,29,30]. If this is performed for every possible application, a better valorization of each slag cluster can be obtained.…”

“…Due to the similar characteristics of slag and gravel, it is possible to use it as a railway ballast [30]. However, the iron content in the slag presents a problem for its valorization due to the conductivity that it may generate.…”