| lühikokkuvõte: |
Pulp and paper industries (PPI) are known for producing large quantities of organic residues. Considering the economic and environmental aspects, the resource recovery from PPI wastes is necessary in order to increase the resource efficiency. In that regard, developing novel biorefinery processes to produce multiple products from PPI wastes is interesting under bio and circular economy. On the other hand, the interest on torrefied biomass is rising over the globe as it can replace the coal. However, the economics of torrefied pellets is not competitive compared to the coal. As the majority of the torrefied pellets production costs are coming from raw materials, sourcing them from low cost resources could be helpful to improve the economic competitiveness of the torrefied pellets over coal. To address the above said two issues, this project will study the feasibility of the torrefaction of pulp and paper industry sludge (PPIS) and integrating it with microbial conversion to produce bioenergy carriers i.e. bio-coal and bio-methane and volatile fatty acids. To achieve this, the expertise of the experienced researcher on biomass torrefaction, process modeling and feasibility analysis will be combined with the expertise of the supervisor on microbial conversion processes and biomass pretreatment. Initially, torrefaction of dewatered PPIS will be carried out in order to establish the biofuel characteristics of torrefied PPIS. Later, anaerobic digestion of torrefaction condensate produced through the torrefaction of PPIS will be studied at varied operating conditions in order to establish the production potential of bio-methane and volatile fatty acids. Finally, the proposed process integration will be simulated to a commercial scale from laboratory experimental results in order to evaluate the techno-economic and environmental feasibility. The proposed study can help the European society to shift toward low carbon economy and achieve sustainable development goals. |
