Modification of the sewage sludge ash P-mineralogy by thermo-chemical
treatment with LF slags© Lehrstuhl fĂĽr Abfallverwertungstechnik und Abfallwirtschaft der Montanuniversität Leoben (11/2022)
As an essential nutrient Phosphorus (P) is an important constituent in fertilisers used in agriculture. However, almost the entire amount of P used in Europe must be imported from sources worldwide. High amounts of P are concentrated in sewage sludge from mostly municipal sewage. From 2029 P-recycling from sewage sludge is mandatory for wastewater treatment plants in Germany. In this study, a process which uses a thermo-chemical treatment of sewage sludge ash (SSA) with Ca-carriers, is developed. The method succeeds in producing materials which match the demands for plant available P and as proven by chemical extraction and pot trials as required by national and European regulations for fertilisers. This was achieved by treating the molten SSA with burnt lime and slags from Ca-rich ladle furnace (LF-slag) which results in the formation of better soluble P-minerals in comparison to the phases whitlockite and apatite mostly abundant in SSA.
Improving the dry magnetic separation of BOF-slag by applying an
innovative pre-treatment process© Lehrstuhl fĂĽr Abfallverwertungstechnik und Abfallwirtschaft der Montanuniversität Leoben (11/2022)
To approach circular economy by enhancing the internal recycling potential of BOFslag, an innovative pre-treatment process for the dry magnetic separation is investigated. It consists of slow-cooling to enlarge the slag crystals, followed by microwave irradiation to generate intergranular cracks to enhance the mineral liberation during comminution. It can be shown that the pre-treatment leads to an increase in the separation degree by at least four percent. This can be further enhanced by a factor of five by using solid-state oxidation.
Innovative Application Methods of Slags from High-Temperature-Gasifying-and-Direct-Melting System© ThomĂ©-Kozmiensky Verlag GmbH (9/2016)
JFE High-Temperature Gasifying and Direct Melting Furnace System (hereinafter Gasifying and Melting System) was developed to treat any kind of wastes and to contribute to energy and material recovery. Gasifying and Melting System was developed by integrating company’s original technologies for the iron-making blast furnace and fluidized bed for incineration plants, which the company cultivated over many years. The company’s advanced technologies in these two different fields were combined and integrated into the unique Gasifying and Melting System. This system is a proven technology that realizes high performance
Material Recycling of Polyolefin-Rich Plastic Fractions© Lehrstuhl fĂĽr Abfallverwertungstechnik und Abfallwirtschaft der Montanuniversität Leoben (11/2014)
The material recycling of plastic waste has still an enormous potential, even in countries like Austria or Germany, which have a highly developed waste treatment system. At the moment, approximately 2/3 of the utilized packaging plastics are treated thermally, i.e. as waste derived fuels, and only 1/3 are routed for material recycling.
RoadMap - Mapping in Case of Landfill Mining© Lehrstuhl fĂĽr Abfallverwertungstechnik und Abfallwirtschaft der Montanuniversität Leoben (11/2014)
Raw materials such as steel and energy are becoming scarcer due to the steady growth of the world population and the resulting consumption change. Hence, it is to be expected that the Prices of primary and secondary raw materials will rise in future even more than present.
Aerobic in situ stabilization of landfills: long-term experience and new developments© IWWG International Waste Working Group (10/2007)
The in situ stabilization of old deposits aims for a lasting and controlled reduction of pollutant emissions from the deposited waste in order to diminish expenditure and the duration of landfill aftercare measures. At three landfills in Germany the stabilization operation over a period of 4 – 6 years was completed successfully.
Prediction and reduction of the duration of landfill aftercare© IWWG International Waste Working Group (10/2007)
A project is being carried out to establish and validate tools which can be used to predict and possibly also influence (reduce) the duration of the aftercare period for modern landfills and to estimate the associated costs.