No abstract

In the present study analysis of co-firing microwave (MW) pre-treated biomass pellets of different origins (wood and wheat straw), with raw pellets (wood, straw, and peat), to control and improve thermochemical conversion of biomass blends and achieve a sustainable use of local energy resources in energy production has been carried out. Effects of MW pre-treatment regimes and composition of blends were studied experimentally using measurements of the weight loss of blends, the yield of volatiles, flame temperature, total heat output from the device, and composition of products. It was found that co-firing MW pre-treated and raw biomass pellets promotes synergistic interaction between components of blends by increasing mass loss rate, the intensity of which depends on the proximate composition of pellets, MW pre-treatment regime and mass fraction of pre-treated pellets in the blend. The most effective synergistic interaction was found when co-firing pre-treated straw or wood pellets with raw peat, which increased the yield of combustible volatiles and heat output from the device as well as improved the composition of emissions. The least effective synergistic interaction was observed when co-firing pre-treated straw with raw wood pellets. Main factors that influenced the thermal and chemical conversion of MW pre-treated blends are discussed considering the effects of MW pre-treatment on the structural changes, elemental and chemical composition, and heating value of pre-treated pellets.

Experimental results on mass transfer within a thin porous layer saturated with ferrofluid are outlined in this paper. From the analysis of particle concentration distribution across the layer it is shown that both the mass diffusion and the Soret coefficients of nanoparticles are remarkably less than those measured in free fluid. The particle transport coefficient changes due to an external uniform magnetic field qualitatively well agree with the predictions of existing theoretical research. The magnetic field that is oriented transversely to the porous layer causes an increase in the diffusion coefficient and a decrease in the Soret coefficient whilst the longitudinal field causes a reduction of the mass diffusion and an intensification of the particle thermodiffusion.

No abstract

No abstract