4 Material und Umwelt
Filtern
Erscheinungsjahr
- 2021 (13) (entfernen)
Dokumenttyp
- Zeitschriftenartikel (9)
- Vortrag (3)
- Forschungsbericht (1)
Schlagworte
- Bottom ash (4)
- Rostasche (3)
- Circular Economy (2)
- Geosynthetics (2)
- Air pollution control (1)
- Antimon (1)
- Artificial ageing (1)
- Auslaugverfahren (1)
- Beschleunigte Alterung (1)
- Chemisches Recycling (1)
- Circular economy (1)
- Coastal protection (1)
- Combustion ion chromatography (1)
- Density separation (1)
- Design of experiments (1)
- Dichtesortierung (1)
- Dry treatment (1)
- Dynamic surface leaching test (1)
- Emission (1)
- Ersatzbaustoffe (1)
- European research area (1)
- Flotation (1)
- Geotextiles (1)
- Geotextilien (1)
- Leaching of waste materials (1)
- Limit values (1)
- Lysimeter (1)
- Marine littering (1)
- Oil (1)
- Oxyfuel-Verbrennung (1)
- Per- and polyfluoroalkyl substances (PFAS) (1)
- Potential toxic elements (1)
- Pyrolyse (1)
- Regulation (1)
- Salts (1)
- Secondary building materials (1)
- Sewage sludge (1)
- Solvolyse (1)
- Thermal treatment (1)
- Wasserbau (1)
- Waste incineration (1)
- Waste-to-energy (1)
- X-ray absorption near-edge structure (XANES) spectroscopy (1)
- Zentrifugalsortierer (1)
Organisationseinheit der BAM
- 4.3 Schadstofftransfer und Umwelttechnologien (13) (entfernen)
Eingeladener Vortrag
- nein (3)
Die Thermische Abfallbehandlung in Abfallverbrennungsanlagen sorgt für eine Inertisierung des Restmülls bei gleichzeitiger Minimierung von abgas- und abwasserseitigen Emissionen. Da der Großteil der Rückstände in verwertbare Sekundärprodukte überführt wird, fördert die thermische Abfallbehandlung die Verwirklichung einer Circular Economy in Europa.
In 2018 municipal solid waste (MSW) incineration in Europe produced nearly 19 Mt of bottom ash (BA); only 46 %-wt. was treated, often in poorly performing plants, leaving behind 10 Mt of untreated and unrecovered BA, destined to landfill. This work was based on the inventory of BA across Europe, and on the hypothesis to achieve complete BA valorisation through two assumptions: treating 100% BA and minimizing the loss of valuable fractions due to technical limitations of state-of-the-art processes in comparison to advanced innovative processes. The research involved three phases: characterization of potential secondary raw materials (metals and mineral fraction) currently lost from untreated (the surplus compared to treatment capacity) and unrecovered BA (the fine fraction) through material flow analysis; environmental assessment (energy balance and net GHG emissions) of complete BA valorisation; investigation of the economic feasibility of complete BA Valorisation through state-of-the-art technologies. The resulting 2.14 Mt loss of valuable materials included 1 Mt Mineral fraction and 0.97 Mt ferrous metals, mostly from untreated BA, and 0.18 Mt non-ferrous metals, mostly from unrecovered BA. The energy balance and GHGs emissions required by the treatment of the currently untreated and unrecovered fractions of BA resulted in energy and GHGs emissions savings. Economic profitability was driven by iron and copper recycling and avoided landfill fees. Profitability was achieved by two thirds of considered countries (average values: NPV 83 M€, ROI 20%, payback time 11 years) with BA mass flow exceeding 0.02 Mt.
The main obstacle to bottom ash (BA) being used as a recycling aggregate is the content of salts and potential toxic elements (PTEs), concentrated in a layer that coats BA particles. This work presents a dry treatment for the removal of salts and PTEs from BA particles. Two pilotscale abrasion units (with/without the removal of the fine particles) were fed with different BA samples. The performance of the abrasion tests was assessed through the analyses of particle size and moisture, and that of the column leaching tests at solid-to-liquid ratios between 0.3 and 4.
The results were: the particle-size distribution of the treated materials was homogeneous (25 wt % had dimensions <6.3 mm) and their moisture halved, as well as the electrical conductivity of the leachates. A significant decrease was observed in the leachates of the treated BA for sulphates (44%), chlorides (26%), and PTEs (53% Cr, 60% Cu and 8% Mo). The statistical analysis revealed good correlations between chloride and sulphate concentrations in the leachates with Ba, Cu, Mo, and Sr, illustrating the consistent behavior of the major and minor components of the layer surrounding BA particles. In conclusion, the tested process could be considered as promising for the improvement of BA valorization.