PROJECT DESCRIPTION
BACKGROUND
France, Germany, Italy, Spain and Turkey generate around 4.1 million tonnes of iron foundry sands and dust wastes every year. In spite of the various treatments on the market, a high proportion of this waste ends up in landfill. In Spain, for example, an average of around 67% of waste by volume is land filled (2013). More valorisation options for these materials are necessary in order to reduce the environmental impact of this type of waste.
OBJECTIVES
The LIFE FOUNDRYTILE project aimed to demonstrate the valorisation of iron foundry sands and dust wastes in the ceramic tile production process, thus contributing to the implementation of Waste Framework Directive (2008/98/EC) and the goals of the Roadmap for a Resource-Efficient Europe. The new applications would have three main benefits: the preservation of natural resources, the increase in foundry waste valorisation and environmental footprint reduction.
The project would first obtain and characterise the samples according to various factors (i.e. mineralogical and chemical composition, moisture, etc.). It would then develop different treatment solutions (a total of 16 solutions combining six different by-products) according to the sample characteristics and the production requirements of four different ceramic tiles. The project would produce 60 tonnes of different ceramic tiles and test them according to different quality parameters (i.e. mechanical resistance, water absorption, etc.). The best performing prototypes (mixtures) would be used to produce a sample of 800 m2 of wall tiles and porcelain tiles. The project results would be used to revise Best Available Techniques Reference Documents (BREFs) for both foundry and ceramic sectors (BREF codes SF and CER).
RESULTS
The project LIFE FOUNDRYTILE demonstrated that sands and dust waste from an iron foundry produced during the production of ceramic tiles could be viably re-used. It compiled a database of foundry by-products and developed criteria for their classification.
These by-products were classified as green, phenol-alkaline, phenol-isocyanate, furanic and silicate-ester, while the ceramic requirements were grouped in four product types. A total of 23 representative samples of foundry by-products were thus characterised to evaluate the viability of their application in the production of ceramic tiles. The critical parameters identified were organic carbon and iron oxide (Fe2O3), with the organic carbon found to be the most limiting factor, especially for dust samples, which have the highest valorisation percentage.
Evaluation of the pre-treatment of foundry by-products showed that thermal and magnetic separation can effectively remove organic matter and iron compounds, increasing the extent of the re-use of waste. However, the project team found that physical separation was not beneficial. The magnetic separation can be easily implemented by the ceramic industry, while the viability for thermal pre-treatment implementation is case specific and requires detailed economic analysis.
After the initial assessment of the effects of the pure foundry by-products, the project proposed and evaluated four valorisation strategies. However, due to the relatively high content of organic carbon, the percentage of sand and clay substitution in the ceramic sector, without pretreatments, is slightly lower than the target 5%. Nevertheless, the project concluded that more than 90% of foundry by-products fractions have the potential to be valorised on a national scale.
The project team also calculated that the new applications decrease environmental impacts by 0.5% to 0.7%, depending on the product, and reduce CO2 emissions by 8 540.7 tonnes of per year. They also estimated that the project methodology saves 415 940 tonnes of iron dust and sand sent from being sent to landfill.
The project contributed to the implementation of the Waste Framework Directive and achieving the goals of the Roadmap for a Resource-Efficient Europe, as well as updating reference documents (BREF). Cooperation with 17 companies from the foundry and ceramic sector was established.
Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).
