Linz-Donawitz Research Articles

The Recycling of Linz-Donawitz (Ld) Converter Slag By Use as a Liming Agent On Pasture Land

Slag is a major by-product of the basic oxygen steelmaking converter process (BOS). Methods are being developed to make use of this by-product and large quantities are now employed in agriculture and in the production of aggregates in several European Community (EC) countries. However, a great deal of slag is still either simply discarded or discharged in landfills. This paper reports the effects over a 3-year period on both soil and crops, of the application of Linz-Donawitz (LD) converter slag on pasture land. Comparative studies were performed using different quantities of low phosphorus LD converter slag and fertilizer on land sown with Dactylis glomerata, Trifolium repens and Lolium perenne. The results showed an increase in soil pH and in the availability of Ca and Mg in the soil exchange complex. Aluminium content was reduced. When LD converter slag and fertilizer were applied together, plants were seen to contain the greatest concentrations of nutrients and greater yields were obtained. © 1995 ISWA

Effects of Linz‐Donawitz (LD) slag on soil properties and pasture production in the Basque country (Northern Spain)

Abstract Linz‐Donawitz (LD) slag, containing 29% calcium (Ca), 21% iron (Fe), and 5% magnesium (Mg), is a by‐product of the iron and steel‐making industry. It is produced in large quantities in Europe and poses a substantial disposal problem. A field trial was conducted to study whether LD slag could be used as a dolomitic liming agent for pastures. The effects of six LD slag rates (0, 1000, 1500, 3000, 5000, and 7500 kg LD slag/ha), with or without NPK fertiliser, on soil properties, pasture yield, and botanical composition were investigated at two locations, Derio and Abadiano (Bizkaia, northern Spain). Soil at Derio was a fine silty, mixed (acid), mesic Typic Udorthent and at Abadiano a fine loamy, mixed (nonacid), mesic Aquic Udifluvent. At Derio, the 3‐year trial was laid out on a newly established pasture of perennial ryegrass (Lolium perenne L.), cocksfoot (Dactylis glomerata L.), and white clover (Trifolium repens L.), whereas at Abadiano the trial was on a resident pasture dominated by yorkshire ...

The recycling of Linz-Donawitz (LD) converter slag by use as a liming agent on pasture land

Slag is a major by-product of the basic oxygen steelmaking converter process (BOS). Methods are being developed to make use of this by-product and large quantities are now employed in agriculture and in the production of aggregates in several European Community (EC) countries. However, a great deal of slag is still either simply discarded or discharged in landfills. This paper reports the effects over a 3-year period on both soil and crops, of the application of Linz-Donawitz (LD) converter slag on pasture land. Comparative studies were performed using different quantities of low phosphorus LD converter slag and fertilizer on land sown with Dactylis glomerata, Trifolium repens and Lolium perenne. The results showed an increase in soil pH and in the availability of Ca and Mg in the soil exchange complex. Aluminium content was reduced. When LD converter slag and fertilizer were applied together, plants were seen to contain the greatest concentrations of nutrients and greater yields were obtained.

Basic Linz‐Donawitz Slag as a Liming Agent for Pastureland

AbstractLinz‐Donawitz (LD) slag, a by‐product of the iron and steelmaking industry (29% Ca, 5% Mg w/w) produced in large quantities in Europe, poses a substantial disposal challenge. A field assay was conducted to study whether LD slag could be used as a dolomitic liming agent for pastures. Six slag rates (0, 1000, 1500, 3000, 5000, and 7500 kg ha−1), with or without NPK fertilizer, were investigated for their effects on soil properties, mineral concentrations of forage, and forage yield at Bizkaia, Spain, on a Derio silty clay soil [fine silty, mixed (acid), mesic Typic Udorthent]. The 3‐yr study was done on a newly established pasture of perennial ryegrass (Lolium perenne L.), cocksfoot (Dactylis glomerata L.), and white clover (Trifolium repens L.). Slag application increased soil pH linearly, especially where fertilizer was not applied. The 7500 kg rate, without NPK fertilization, increased soil pH from 5.3 to 6.5. When 3000 kg ha−1 of slag was applied, the increase in soil pH was accompanied by a decrease of AI saturation percentage in the cation exchange complex, to <10%. At this rate, exchangeable Ca and Mg increased in comparison with the control, by a factor of 1.8 and 2.3, with and without fertilization, respectively. Slag application resulted in higher Ca, Mg, and P, lower K and Mn plant concentrations, and increased herbage yield. LD slag appears to be a useful liming material for correcting soil acidity on pasture soils and for increasing Ca, Mg, and P concentrations in plants.

Electrical resistivity, magnetoresistance, and morphology of vapor-grown carbon fibers prepared in a mixture of benzene and Linz–Donawitz converter gas by floating catalyst method

Vapor-grown carbon fibers (VGCF's) were prepared in a mixture of benzene and Linz–Donawitz converter gas using floating catalytic seeds derived from ferrocene, cobalt acetylacetonate, and thiophene. The diameters of the fibers thus grown were in the range of 2–7 μm. The fibers were heat-treated in argon atmosphere at temperatures between 1700 and 3000 °C. The electrical resistivity at room temperature and magnetoresistance at liquid nitrogen temperature were measured for the as-grown and heat-treated fibers, and morphology of the heat-treated fibers was observed with a scanning electron microscope. The electrical resistivity was nearly similar to that obtained for VGCF's prepared on a substrate in a mixture of benzene and hydrogen. The size effects on the resistivity and magnetoresistance were observed. The magnetoresistance was also found to depend on the heat-treatment time. The magnetoresistance results showed that a transition heat-treatment temperature for the magnetoresistance change from negative to positive was between 2200 and 2300 °C, indicating the graphitizable nature of the present fiber. A characteristic polygonal appearance was observed for the fibers heat-treated above 2500 °C.

Mechanical properties of vapor-grown carbon fibers prepared from benzene in Linz–Donawitz converter gas by floating catalyst method

Tensile strength and Young's modulus were determined for vapor-grown carbon fibers (VGCF's) prepared from benzene in Linz–Donawitz converter gas (LDG) by the floating catalyst method. The tensile strength decreased with increasing diameter and volume and depended strongly on whether the fiber was straight or crooked. The average tensile strength of straight fibers was 2.05 GPa, while that of crooked fibers was 1.09 GPa. The latter broke at bends in the fiber where they acted as defects. The average Young's modulus of straight fibers was 163 GPa, while that of crooked fibers was a little higher at 197 GPa. VGCF's prepared in LDG appeared to have comparable mechanical properties to those grown in hydrogen.