Pelleting of Pine and Switchgrass Blends [electronic resource] : Effect of Process Variables and Blend Ratio on the Pellet Quality and Energy Consumption

• Ngôn ngữ: eng
• Ký hiệu phân loại: 621.47 Solar-energy engineering
• Thông tin xuất bản: Washington, D.C. : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Energy Efficiency and Renewable Energy ; Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2019
• Mô tả vật lý: Size: Article No. 1198 : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 262837
• Chủ đề: 1. 09 biomass fuels; 2. 2-inch top pine residue + switchgrass blends; 3. Pellet quality; 4. Pelleting process variables; 5. Specific energy consumption

Tóm tắt

 The blending of woody and herbaceous biomass can influence pellet quality and the energy consumption of the process. This work aims to understand the pelleting characteristics of 2-inch top-pine residue blended with switchgrass at high moisture content. The process variables tested are blend moisture content, length-to-diameter (L/D) ratio in the pellet die, and the blend ratio. A flat die pellet mill was also used in this study. The pine and switchgrass blend ratios that were tested include: (1) 25% 2-inch top pine residue with 75% switchgrass
  (2) 50% 2-inch top pine residue with 50% switchgrass
  and (3) 75% 2-inch top pine residue with 25% switchgrass. The pelleting process conditions tested included the L/D ratio in the pellet die (i.e., 1.5 to 2.6) and the blend moisture content (20 to 30%, w.b.). Analysis of experimental data indicated that blending 25% switchgrass with 75% 2-inch top pine residue and 50% switchgrass with 50% 2-inch top pine residue resulted in pellets with a bulk density of >
  550 kg/m<
 sup>
 3<
 /sup>
  and durability of >
  95%. Optimization of the response surface models developed for process conditions in terms of product properties indicated that a higher L/D ratio of 2.6 and a lower blend-moisture content of 20% (w.b.) maximized bulk density and durability. Higher pine in the blends improved the pellet durability and reduced energy consumption.