WP5 – Phytostabilization of primary slags and secondary waste resulting from hydrometallurgical treatment


It is possible, following WP2 and WP3 investigations, that some slag types will not be relevant for hydrometallurgical treatment. It is also foreseeable that the hydrometallurgical process applied in WP4 generates secondary waste that do not meet the environmental acceptability criteria for a safe re-use in the field of civil engineering.

Therefore, HYPASS will implement a phytostabilization strategy, for limiting wind and water erosion of steel slag dumps and to prevent leaching and run-off of  contaminants, whether they are primary slags or by-products resulting from the hydrometallurgical treatment. The WP5 will address this issue at two different “Technology Readiness Levels” (TRLs).

A set of laboratory experiments (TRL 3-4) will study the effects of “Arbuscular Mycorrhizal Fungi” (AMF) both on the stimulation of plant growth and on the decrease of metals accumulation by plants.

The phytostabilization effectiveness will be examined on a larger scale (TRL of 6-8) at site scale, where the implementation of a phytostabilization rehabilitation project is planned.

Description of work

Task 5.1. – The study of AMF symbiosis into primary slags in controlled conditions (M1-M12)

Task 5.2. – The study of AMF symbiosis into primary slags in “field” conditions (M1-M12)

Task 5.3. – The study of AMF symbiosis into secondary waste resulting from the  hydrometallurgical treatment (M24-M36)

Task 5.4. – The study of plant development and metal accumulation on a large  metallurgical slagheap processed by phytostabilization (M1-M36)


Phone: +33 4 77 42 01 23

Postal address
École des Mines de Saint-Étienne
158, cours Fauriel
CS 62362

F-42023 Saint-Étienne cedex 2