INDUSTRIAL CROPS AND PRODUCTS, sa.186, ss.1-10, 2022 (SCI-Expanded)
In order to achieve economically viable and sustainable solid biofuel production from perennial grasses, high
biomass productivity must be complemented by good combustion quality. The aim of this research was to
compare the combustion quality of 7 cool-season perennial grasses, comprising bulbous canary grass, reed canary
grass, smooth brome grass, orchard grass, tall wheatgrass, tall fescue, and perennial ryegrass, and 3 warm-season
perennial grasses, comprising switchgrass, miscanthus, and giant reed, over 2 harvest times (autumn, winter/
early spring) in 2 contrasting semi-arid environments (Adana, and Cankiri, Turkey). Delaying the harvest from
the autumn to the winter or the spring significantly increased the lignin contents of each of the 3 warm-season
grasses and generally decreased the contents of all of the minerals, except for Al and Fe, in miscanthus and
switchgrass, and K and Na in giant reed, at both locations. Similar trends were also generally observed for all of
the cool-season grasses, except for the orchard grass that was grown in Cankiri. Additionally, delayed harvest
resulted in lower slagging tendency and sintering risk in all of the perennial grass species, except for giant reed in
Cankiri. However, the autumn harvest caused significantly higher lignin, but generally lower N, P, K, Ca, S, Si, Al,
and Fe contents, slagging tendency, and sintering risk in most of the cool-season grasses that were grown in
Adana. On the other hand, despite the autumn harvest in Adana, and the spring harvest in Cankiri provided a
substantial improvement in combustion quality of the cool-season grasses, mainly due to the reduced mineral
and increased lignin contents, they still exhibited relatively lower combustion quality than miscanthus and
switchgrass, especially in Adana. These results showed that further effort is needed to improve the combustion
quality of cool-season grasses in order for them to be primary biomass feedstock alternatives for dry marginal
lands of semi-arid environments.