Water purification

Why use biochar for water purification?

Biochar has high porosity and a large surface area and therefore a high cation exchange capacity, as in a good ability to bind positive ions. The ability to bind ions allows biochar to capture heavy metals from the water that passes through the plantings where it is used. The quality of the drainage water therefore increases, which in turn reduces the risk of contaminating lakes, seas and other watercourses. The ability to bind heavy metals makes biochar a very interesting material in green-blue-grey systems in street spaces aimed at handling storm water.

WHAT WE DO IN THE PROJECT REST TILL BÄST

In Rosendal in Uppsala, the municipality of Uppsala is building a new type of road superstructure, where the finest fractions in the reinforcement sheet layer under streets with car traffic have been removed and only coarser materials remain. The idea is to create a reinforcement sheet layer with a much higher number of large pores, which will provide space for plant roots and air, and which can also be used to store water. In order to improve the reinforcement sheet layer’s function as a storm water filter and plant substrate, biochar has been added to certain plant beds. Within Rest till Bäst, the municipality of Uppsala, along with SLU, will compare the purification level in the drainage water from plant beds both with and without biochar.

COMMITTED PROJECT PARTNERS

CONTACT

Markus Paulsson
markus.paulsson@lund.se
+46 (0) 46-359 53 36
City of Lund, City Office
221 00 Lund, Sweden

REST TILL BÄST

Rest till Bäst is a Vinnova-funded project whose purpose is to develop solutions for managing society’s organic residues and create a much needed beneficial product, while at the same time minimising environmental and climate impact.