As today’s society searches for renewable energy sources that could be an alternative to fossil fuels, biomass and biofuels provide a promising solution. Switchgrass is one of feedstocks that can be utilized as a ren...As today’s society searches for renewable energy sources that could be an alternative to fossil fuels, biomass and biofuels provide a promising solution. Switchgrass is one of feedstocks that can be utilized as a renewable energy source. When farming, one of the most important considerations is efficiency. This consists of several factors, including time, fuel use, economic and power efficiencies of equipment. Inefficient field operations could increase harvesting costs and in turn could cause hesitation when a farmer decides to participate in biomass production. This literature review will cover the main elements of biomass and biomass handling relating to determining harvesting efficiency and biomass quality for switchgrass round bales. Specifically, the following sections include past research activities relating to biomass harvesting, biomass bale quality during outdoor storage, logistics models, and data collection methods during biomass harvesting. The objective of this review is to examine status and needs for switchgrass round bale harvesting operations and the expenses that come with it.展开更多
针对国内秸秆打包机不能进行田间收获打包作业的现状,设计了收获粉碎式秸秆压块打包一体机。以7 3.5 k W拖拉机作为牵引机,利用捡拾收割装置进行秸秆捡拾收获,通过二次粉碎抛送装置完成秸秆的二次粉碎与抛送,实现了秸秆的田间收获压块...针对国内秸秆打包机不能进行田间收获打包作业的现状,设计了收获粉碎式秸秆压块打包一体机。以7 3.5 k W拖拉机作为牵引机,利用捡拾收割装置进行秸秆捡拾收获,通过二次粉碎抛送装置完成秸秆的二次粉碎与抛送,实现了秸秆的田间收获压块打包作业。田间试验表明:该机捡拾收获效果良好,损失率低,作业效率达到了2.84t/h,草捆密度133.4kg/m^3,满足农作物秸秆收获作业要求,为秸秆综合利用提供了技术支持。展开更多
Miscanthus is an emerging dedicated energy crop, which can provide excellent yield on marginal lands. However, this crop is more difficult to harvest than many conventional energy crops such as corn stover and switchg...Miscanthus is an emerging dedicated energy crop, which can provide excellent yield on marginal lands. However, this crop is more difficult to harvest than many conventional energy crops such as corn stover and switchgrass due to its tall and rigid stalks. Crop samples for laboratory studies were collected from the field and the effects of roll spacing, roll speed, and crop input of a mechanical conditioning device on the physical conditions of miscanthus were studied in a lab setting. Test results showed that mechanical conditioning is effective to change the physical conditions of miscanthus to make baling possible or easier. Results also showed that the roll spacing had the most significant impact on the physical conditions of miscanthus, shown by a 115% increase in conditioning over a 0.95 cm (75%) reduction in roll spacing. Increased roll spacing and speed were shown to decrease the amount of torque required to condition the miscanthus.展开更多
This study investigated the influence of both shaking duration and number of trees per bale on postharvest needle characteristics such as percentage needle loss, needle retention duration and explored the physiologica...This study investigated the influence of both shaking duration and number of trees per bale on postharvest needle characteristics such as percentage needle loss, needle retention duration and explored the physiological roles of endogenous ethylene and volatile terpene compounds (VTCs). To accomplish these objectives, 25 six-year-old trees were detached and exposed to a range of shaking durations (0 to 60 sec.), and 30 six-year-old detached trees were exposed to baling treatments from 0 to 5 trees. Response variables measured were percent needle loss, needle retention duration, average water use, ethylene and volatile terpene compound evolution. Trees shaken for 60 seconds lost 16% less needle compared to control, which was consistent with the decrease in percent needle loss with increasing shaking duration. Baled trees lost 13% more needles compared to control, but percent needle loss was observed to decrease with increasing number of trees in a bale. These trends corresponded with increasing ethylene and VTC evolutions, where the longer the shaking duration or larger number of trees in a bale, the higher the ethylene and VTC evolutions. One can therefore draw inference that mechanical perturbation as a result of shaking and baling induce biosynthesis and regulation of ethylene and VTC in balsam fir trees in an effort to regulate postharvest needle abscission.展开更多
文摘As today’s society searches for renewable energy sources that could be an alternative to fossil fuels, biomass and biofuels provide a promising solution. Switchgrass is one of feedstocks that can be utilized as a renewable energy source. When farming, one of the most important considerations is efficiency. This consists of several factors, including time, fuel use, economic and power efficiencies of equipment. Inefficient field operations could increase harvesting costs and in turn could cause hesitation when a farmer decides to participate in biomass production. This literature review will cover the main elements of biomass and biomass handling relating to determining harvesting efficiency and biomass quality for switchgrass round bales. Specifically, the following sections include past research activities relating to biomass harvesting, biomass bale quality during outdoor storage, logistics models, and data collection methods during biomass harvesting. The objective of this review is to examine status and needs for switchgrass round bale harvesting operations and the expenses that come with it.
文摘针对国内秸秆打包机不能进行田间收获打包作业的现状,设计了收获粉碎式秸秆压块打包一体机。以7 3.5 k W拖拉机作为牵引机,利用捡拾收割装置进行秸秆捡拾收获,通过二次粉碎抛送装置完成秸秆的二次粉碎与抛送,实现了秸秆的田间收获压块打包作业。田间试验表明:该机捡拾收获效果良好,损失率低,作业效率达到了2.84t/h,草捆密度133.4kg/m^3,满足农作物秸秆收获作业要求,为秸秆综合利用提供了技术支持。
文摘Miscanthus is an emerging dedicated energy crop, which can provide excellent yield on marginal lands. However, this crop is more difficult to harvest than many conventional energy crops such as corn stover and switchgrass due to its tall and rigid stalks. Crop samples for laboratory studies were collected from the field and the effects of roll spacing, roll speed, and crop input of a mechanical conditioning device on the physical conditions of miscanthus were studied in a lab setting. Test results showed that mechanical conditioning is effective to change the physical conditions of miscanthus to make baling possible or easier. Results also showed that the roll spacing had the most significant impact on the physical conditions of miscanthus, shown by a 115% increase in conditioning over a 0.95 cm (75%) reduction in roll spacing. Increased roll spacing and speed were shown to decrease the amount of torque required to condition the miscanthus.
文摘This study investigated the influence of both shaking duration and number of trees per bale on postharvest needle characteristics such as percentage needle loss, needle retention duration and explored the physiological roles of endogenous ethylene and volatile terpene compounds (VTCs). To accomplish these objectives, 25 six-year-old trees were detached and exposed to a range of shaking durations (0 to 60 sec.), and 30 six-year-old detached trees were exposed to baling treatments from 0 to 5 trees. Response variables measured were percent needle loss, needle retention duration, average water use, ethylene and volatile terpene compound evolution. Trees shaken for 60 seconds lost 16% less needle compared to control, which was consistent with the decrease in percent needle loss with increasing shaking duration. Baled trees lost 13% more needles compared to control, but percent needle loss was observed to decrease with increasing number of trees in a bale. These trends corresponded with increasing ethylene and VTC evolutions, where the longer the shaking duration or larger number of trees in a bale, the higher the ethylene and VTC evolutions. One can therefore draw inference that mechanical perturbation as a result of shaking and baling induce biosynthesis and regulation of ethylene and VTC in balsam fir trees in an effort to regulate postharvest needle abscission.
