Table 4.
Biochar standards for obtaining the European certificate of feed-grade biochar
| Criteria | Biochar co-feed criteria values |
|---|---|
| Polycyclic aromatic hydrocarbons | Less than 4 mg kg−1 |
| Carbon content | More than 80% |
| Heavy metals | Arsenic: Less than 2 mg kg−1 |
| Lead: Less than 10 mg kg−1 | |
| Cadmium: Less than 1 mg kg−1 | |
| Mercury: Less than 0.1 mg kg−1 | |
| Benzo-a-pyrene | Less than 25 µg kg−1 |
| The dioxin-like polychlorinated biphenyls | A start value of 0.35 ng TE kg−1 |
| Polychlorinated dibenzo-p-dioxins and dibenzofurans along with dioxin-like polychlorinated biphenyls | Less than 1.25 ng TE kg−1 |
| Polychlorinated dibenzo-para-dioxin/ Polychlorinated dibenzofurans | A limit of 0.75 ng TE kg−1 |
| Fluor | Less than 150 mg kg−1 |
| Dry matter, insoluble-, and crude- ashes | Same as standard values imposed by EU regulations for feed |
| Crude protein, crude fat, and crude fibre | 0 g kg−1 due to pyrolysis effect |
| Paint and solvents | Free |
| Contaminants such as plastics, rubber, and electronic scrap | Free |
All parameter values are calculated at 88% (dry matter basis). The various criteria and their values are summarised