Phosphate Fertilizer Derived From Steel Slag
Steel slag is an unavoidable byproduct of the steelmaking process. Steel slag has, until recently, largely been thrown away as waste. However, an innovative process has been developed to turn steel slag into an important resource – phosphate fertilizer.
Phosphate fertilizer is essential to modern agriculture and is used the world over to increase crop yields. It helps the plants to better absorb soil minerals and increases their growth. To make the fertilizer, steel slag is heated to temperatures of around 1450 degrees Celsius in a rotary kiln. This process causes reactive substances in the slag to form compounds which, when cooled, are highly concentrated phosphates.
This improved form of fertilizer is more effective than rock phosphates, which are the most common form of phosphate fertilizer and consist of weathered phosphoric rocks. Rock phosphates, while they do have the same chemically active phosphate compounds and have a long history of use in agriculture, are a poorer source of the nutrients needed for crop growth. Steel slag-based fertilizer, on the other hand, has a much greater concentration of phosphates and is therefore a much better choice.
Steel slag-based fertilizer also has other benefits. The reactive substances in it provide a slow release of nutrients, almost like a time-release capsule. This means that plants have a steady supply of nutrients over a longer period of time. The slag fertilizer also contains small amounts of calcium and magnesium, both of which are beneficial to plants.
The production of phosphate fertilizer from steel slag is not only an important method of repurposing an otherwise useless waste product, it also helps to reduce the cost of the fertilizer and minimizes environmental impacts. By using steel slag, miners and processors dont have to search for new phosphate deposits, saving time and money. Less chemical processing is also needed, as the beneficial compounds are already in the slag. Furthermore, this method is much less energy-intensive and therefore more efficient than production of rock phosphate-based fertilizer.
Overall, steel slag-based fertilizer is a beneficial and important resource. The use of steel slag for phosphate fertilizer provides a much more efficient and effective way of supplying farmers with vital nutrients that help to make sure their crops thrive.
