TOWARDS ‘BEYOND THE ZERO WASTE CONCEPT’: INNOVATIVE SOLUTIONS FOR VALORIZATION OF FINE RESIDUAL WASTE FRACTION FROM LANDFILLS: RARE EARTH ELEMENTS POTENTIAL

The growing population of the planet and the population’s desire for ever-higher welfare standards have contributed to a linear economy-based consumer society model that is one of the main reasons for the increased volume of waste. Global sustainability, mitigation of climate change, and the reduction of pollution are strongly related to the waste management issue, and there is a need to switch from linear economy models to the circular economy. The maintaining solution for keeping and storing waste over the last century has been landfilling as its costs are the lowest. A sustainable approach such as landfill mining (LFM) can be applied to recover rare earth elements (REEs) and other valuable metals from waste that make fundamental assets in terms of economy and essential for developing industrial technologies. This study investigated concentrations of REEs and other metals in waste material. Samples from IdaVirumaa (Estonia) landfilled waste fine fraction were taken to estimate the element concentration proceeded through sequential extraction. Additionally, the method of clay modification was developed that may serve as a sorbent to extract the REEs from the inert landfill fine fraction waste using hydroxyapatite modified clay. The amount of REEs might become of industrial interest if a feasible landfill mining approach for remediation of landfills and degraded industrial soils is applied together with innovative recovery methods, e.g., sorption by modified clays.