Data_ Integrating torrefaction of pulp industry sludge with anaerobic digestion to produce bioenergy and biochemicals: Techno-economic and environmental feasibility analysis

In order to improve the economic competitiveness of bioenergy carriers and biochemicals, they must be produced<br> from low-cost or no-cost feedstock and at a reduced operational expenses. In that regard, this study<br> focused on understanding the techno-economic feasibility of using pulp sludge as a low-cost alternative feedstock<br> to forestry biomass in torrefaction. Economic feasibility of further integrating pulp sludge torrefaction with<br> anaerobic digestion to produce energy, biomethane and volatile fatty acids (VFA) was also studied. The operational<br> expenses were around 8.2 and 2.04 M€ and the minimum selling price of torrefied pellets was 407 and<br> 189 €/t for forestry biomass torrefaction and pulp sludge torrefaction respectively. In case of integrated approaches,<br> VFA production showed higher economic feasibility with a torrefied pellets selling price of 163 €/t<br> compared with biomethane production (213 €/t). The biomethane and VFA selling price can be reduced by 90<br> and 64% compared with current market price at torrefied pellets selling price of 260 €/t. Sensitivity analysis<br> revealed that, moisture content of the sludge is the main influencing parameter on the overall economic feasibility<br> of the pulp sludge torrefaction. The environmental analysis showed that pulp sludge torrefaction has higher<br> emissions compared with forestry biomass torrefaction.