Steel slag to correct soil acidity and as silicon source in coffee plants

Abstract

Slags from the iron and steel industry may be used in agriculture to correct soil acidity. Current assay assesses the effect of iron and steel industry´s slag, derived from stainless steel, and compares it to limestone as soil acidity corrective and silicon source in coffee plants. The experiment was conducted between December, 2012 and January, 2014 in the municipality of Machado MG Brazil, in a 4-year-old coffee plantation, cultivar Catuaí Amarelo IAC 30. Experimental design comprised randomized blocks in a 2x4 factorial scheme, with control and four replications. Treatments combined two soil acidity correctives, namely, stainless steel slag ("Agrosilício") and limestone; 4 corrective doses corresponding to 0.5; 1; 1.5; 2 times the amount required to raise index base saturation (V%) of the soil´s surface layer (0 to 0.2m) by 60%. Control did not contain any soil correction. Soil samples were collected during the experiment at depths 0 to 0.1m; 0.1 to 0.2m; 0.2 to 0.4m; similarly, samples of coffee leaves, at 180 and 390 days, respectively, after the application of correctives. Stainless steel slag showed the same efficiency as limestone in soil acidity correction at 0 to 0.1m layer, and in providing Ca 2+ to the coffee plant. Stainless steel slag does not correct soil acidity at 0.1 to 0.2 and 0.2 to 0.4 m layers in coffee plants within a 180 day period. Stainless steel slag increases silicon rates in the soil and in the coffee leaves, and increases yield when compared to limestone.

Integrating Arid Areas in the Global Bioeconomy: Opportunities and Challenges toward Sustainable Biomass Generation and Management

“…In particular, CaO, SiO 2 , MgO, FeO, and P 2 O 5 from steel slag can be used as fertilizers. These mineral oxides are key micronutrients to plants and they can also participate as carbon capture matrices by carbonation, which could also further improve the growth rate and yields of crops. − Therefore, valorization of slag toward increase biomass growth, and thus carbon capture in biomass, as well as carbon biofixation in soils represent an opportunity to synergistically close the loop and contribute to the decarbonization of the steel industry.…”

Effect of liming of sod-podzolic soils with by-products of steel production on soil acidity and composition of wash water (column experiments)

“…Correction of acidity with slag occurs similarly to the use of limestone. In addition to the decrease in acidity levels, Ca and Mg supply also occurs in soil (Torkashvand and Sedaghathoor 2007;Deus et al 2014;Mantovani et al, 2016). Suwarno et al, 2001) found that application of steel slag showed positive effect on plant growth compared to the dolomite liming that had no effect on P uptake by plants.…”

“…Shilnikov et al (2011) generalized results of lysimetric studies over 25 years and have shown that to compensate for the natural removal of magnesium and calcium from soils, their annual intake of at least 400-450 kg / ha in terms of CaCO3 is required. Various researchers reported results of using steel slag in agriculture and showed that the correct application of these waste materials increase the pH in acidic soils, increase content of phosphorus, calcium and magnesium, as well as increase the content of silicon (Deus et al 2014;Mantovani et al 2016;Souza and Korndörfer 2010), thus ultimately contributing to the increase in crop yields (Deus et al 2018).…”

The Comprehensive Utilization of Steel Slag in Agricultural Soils

“…The results of the researchers with the use of steel slag in agriculture have demonstrated that the proper application of these residues brings benefits on the chemical attributes of the soil, such as increase of pH in acidic soils; increase in the nutrient content of phosphorus, calcium, and magnesium; and increase in the content of the beneficial element silicon [6,[11][12][13][14]; these aspects contribute to greater crop production.…”

“…Correction of acidity with slag occurs similarly to the use of limestone. In addition to the decrease in acidity levels, Ca and Mg supply also occurs in soil [6,11,12], with positive effects for crops such as potatoes, rice, black oats, beans, soybeans, alfalfa, coffee, and sugarcane, among others, making steel slag a source capable of being used instead of limestone [11,13,[17][18][19][20][21]23].…”