Chemical composition of agromass ash and its influence on ash melting characteristics

Investigation of Buckwheat Hulls as Additives in the Production of Solid Biomass Fuel from Straw

“…When explaining and validating differences in ash melting characteristics, the elemental composition and potential influence of a particular element must be taken into account. The results of Tables 2 and 3 correlate with the results of [24][25][26], and suggest that Ca, Mg, and Al increase the ash melting temperature, while K, Na, P, and especially Si decrease it. This can be observed from the low melting temperatures of pure straw ash as they contained high K and Si concentrations and low Ca concentrations.…”

“…Figure 1a shows a very marked change in N, S, and Cl concentration for buckwheat hulls, wheat straw, and wood chips. From [9,22,23,26] it is clear that the change in the concentration of N, S, and Cl in the pure raw material was several times larger than the changes in concentration of C, H, and O. The concentration of N was 4 times higher, while concentrations of S and Cl were 1.5 times higher in buckwheat hulls compared to the concentration of the respective elements reported in [21].…”

“…It should be noted that the composition of the produced ash depends on the pure elements and various oxides [24][25][26]. Thus, the total content of the elements presented in Table 2 at their oxide (Figure 2) content ranges from 70% to 86% of the ash composition, with pure elemental concentrations between 45% and 51% of the elemental composition of the ash.…”

“…However, judging from studies on the energetic properties of wood, wood pellets, and peat [21][22][23], buckwheat hulls have comparatively high energy potential [21]. This exploration of wheat straw and buckwheat hull mixtures aims to exploit the energy potential of buckwheat hulls and evaluate the ash melting characteristics by individual element impact assessments, enabling comparison with the results obtained in [24][25][26]. For this purpose, we compared additional pure elements from pure biomass ash (buckwheat hulls [16], straw [5,9,12,13,25,27], wood [9,12,13,25,27]) and their oxides, because of a lack of research on the use of buckwheat hulls as an additive in straw thermal conversion processes.…”