Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati 781 039, Assam, India.
Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati 781 039, Assam, India.
Bioresour Technol. 2018 Aug;261:294-305. doi: 10.1016/j.biortech.2018.04.011. Epub 2018 Apr 12.
This study reports pyrolysis kinetics of biomass blends using isoconversional methods, viz. Friedman, FWO and KAS. Blends of three biomasses, viz. saw dust, bamboo dust and rice husk, were used. Extractives and volatiles in biomass and minerals in ash had marked influence on enhancement of reaction kinetics during co-pyrolysis, as indicated by reduction in activation energy and increase in decomposition intensity. Pyrolysis kinetics of saw dust and rice husk accelerated (positive synergy), while that of bamboo dust decelerated after blending (negative synergy). Predominant reaction mechanism of all biomass blends was 3-D diffusion in lower conversion range (α ≤ 0.5), while for α ≥ 0.5 pyrolysis followed random nucleation (or nucleation and growth mechanism). Higher reaction order for pyrolysis of blends of rice husk with saw dust and bamboo dust was attributed to catalytic effect of minerals in ash. Positive ΔH and ΔG was obtained for pyrolysis of all biomass blends.
本研究使用等转化率方法（即 Friedman、FWO 和 KAS）报告生物质混合物的热解动力学。使用三种生物质，即锯末、竹粉和稻壳进行了混合。生物质中的萃取物和挥发物以及灰分中的矿物质对共热解过程中反应动力学的增强有显著影响，表现为活化能降低和分解强度增加。锯末和稻壳的热解动力学加速（正协同作用），而竹粉的热解动力学在混合后减速（负协同作用）。所有生物质混合物的主要反应机制在较低转化率范围（α ≤ 0.5）内为三维扩散，而对于α ≥ 0.5，热解遵循随机成核（或成核和生长机制）。稻壳与锯末和竹粉混合物热解的较高反应级数归因于灰分中矿物质的催化作用。所有生物质混合物热解的ΔH 和ΔG 均为正值。
