标题：Segmented heating carbonization of biomass: Yields, property and estimation of heating value of chars
作者：Qi, Jianhui; Zhao, Jianli; Xu, Yang; Wang, Yongjia; Han, Kuihua
作者机构：[Qi, Jianhui; Zhao, Jianli; Han, Kuihua] Shandong Univ, Sch Energy & Power Engn, Jinan 250061, Shandong, Peoples R China.; [Qi, Jianhui] Univ Queens 更多
通讯作者地址：[Han, KH]Shandong Univ, Sch Energy & Power Engn, Jinan 250061, Shandong, Peoples R China.
关键词：Biomass; Carbonization; Biomass upgrading; Fuel property; Higher heating; value
摘要：To provide preferable operating conditions for biomass carbonization, the carbonization properties of maize straw, cotton stalk and poplar wood were investigated in nitrogen atmosphere by segmented heating process at different final temperatures of 300-800 degrees C for 1 h. Segmented heating carbonization contributes to higher ratio of mass and energy yields than a constant temperature/linear heating process with final temperature of around 300 degrees C. The fuel properties and characteristics of raw and carbonized biomass were analysed systematically. Increasing carbonization temperature, the fuel ratios of the obtained chars rise exponentially, and the profile of atomic H/C ratio versus atomic O/C ratio approximately decreases linearly. There are small changes of sulphur and nitrogen content in the chars. To provide an estimation method for higher heating value for torrefied/carbonized biomass, a new correlation is proposed based on ultimate analysis. The correlation is HHV = 19.9579 + 0.2184C + 0.3355H - 0.12090 - 1.3836N - 5.4680S, which is validated through experimental data. The correlation has a low level of errors, that the correlation efficient, mean absolute error, average absolute error and average bias error are 0.971, -6.75 x 10(-6) MJ, 1.2% and 0.02% respectively. This work will make a contribution to the biomass pretreatment process. (C) 2017 Elsevier Ltd. All rights reserved.