Occurrence form and release and migration characteristics of potassium during combustion of torrefied biomass

被引：0
|
作者：
Yu Z. [1 ]
Liu Q. [1 ]
Zhong W. [1 ]
Zhou J. [1 ]
机构：
[1] Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing
来源：
Liu, Qian (liuqian@seu.edu.cn) | 1600年 / Materials China卷 / 72期
关键词：
Alkali metal K; Chemical fractionation; Combustion; Fixed bed; Thermodynamic equilibrium calculations; Torrefied biomass;
D O I：
10.11949/0438-1157.20201108
中图分类号：
学科分类号：
摘要：
Rice straws and cotton stalks were selected as raw materials. After torrefaction pretreatment, the fixed-bed combustion experiment and HSC Chemistry thermodynamic equilibrium calculations were conducted to obtain the release and migration characteristics of alkali metal K during the combustion of torrefied biomass. The results showed that there was a small amount of water-soluble K release and its conversion to ammonium acetate dissolved K during torrefaction, and its conversion and release capacity was positively correlated with Cl/K. The ash formation rate of torrefied biomass decreased with the increase of combustion temperature, while the release rate of K changed with the temperature on the contrary; K was released in the form of water-soluble K, ammonium acetate dissolved K and acid-soluble K, and its main release form was K chloride and KOH. In addition, water-soluble K and ammonium acetate dissolved K were mainly converted to char-K at 600℃, and mainly converted to K silicate at 700-900℃. As the temperature rose, its conversion volume continued to increase. Compared with the raw biomass, torrefied biomass had a higher ash formation rate; in addition, torrefaction promoted the conversion of ammonium acetate dissolved K to acid-soluble K or potassium silicate during the combustion of biomass, and at the same time inhibited the release of water-soluble K. Therefore, the release rate of K during the combustion of torrefied biomass was lower. The inhibition of K release during the combustion of biomass by torrefaction is positively correlated with the release rate of Cl during the torrefaction. © 2021, Editorial Board of CIESC Journal. All right reserved.
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页码：2258 / 2266
页数：8
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