高温液态水预处理木质纤维素类生物质的实验研究
文献类型：学位论文
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| 作者 | 徐明忠 |
| 学位类别 | 硕士 |
| 答辩日期 | 2008-06-03 |
| 授予单位 | 中国科学院广州能源研究所 |
| 授予地点 | 广州能源研究所 |
| 导师 | 袁振宏 |
| 关键词 | 高温液态水水解 木质纤维素类生物质 水解动力学 水解反应器 |
| 其他题名 | The Study on Hot Liquid Hydrolysis of lignocellulosic biomass |
| 中文摘要 | Lignocellulosic biomass has been widely applied to produce ethanol. Enzymatic hydrolysis has been proved to be the best way to hydrolysis cellulose. However, due to the stability of lignocellulosic biomass’s structure, the raw materials should be pretreated. Hot liquid water can efficiently hydrolyze hemicellulose and reserve cellulose, considerd to be a competitive pretreatment process. In order to study the hydrolysis merchanism and providing datas for the continuous hydrolysis reactor desgin, a review of world ethanol was promoted. Then local rice straw was investigated on the best condition by liquid water batch hydrolysis and the products were analyzed. Furthermore, xylan, rice straw and palm shell were hydrolyzed under the best condition to meet the math model, and the kinetic parameters were canculated. Finally a continuous reactor for biomass hydrolysis was designed based on the above datas. The effect of reaction temperature and time, the mass ratio of liquid to solid ratio(L/S), rotating speed and preheating time on the suagr yield, concentration and raw material conversion ration had been investigated by hot liquid water batch hydrolysis of rice straw.The optimum hydrolysis conditions from a comprehensive consideration haver be determine as follows. The temperature was 200℃, and the presssure was 4.0MPa.The ratio of liquid to solid ratio was 20 and the reaction time was 10 minutes.Furthermore, the rotating speed was 500r/min and preheating time was 60 minutes.The liquid product had a sugar concentration of 8.9g/l and a sugar yield up to 51.85%, as well as a mass conversion ratio of 48.18%. The bed-shrinking percolation experiments indicated that under the condition of temperature at 160℃, L/S at 20:1 and time at 42 minutes, the maximal sugar concentration was obtained at 6.23g/l and the sugar yield was 41.53%. The residue was test by Van Soest methods that the conversion ratio of hemicellulose, cellulose, lignin and ash were 88.90%, 5.72%, 20.18% and 33.05 % respectively. A SEM test and industrial and element analysi were carried out on the residue under optimal condition to identify the hydrolysis result. The results showed that the pretreatment was efficient. A first-oder squential kinetic modeling of hot liquid water hydrolysis of xylan, rice straw and palm shell were employed on the basis of kenetic experiment data and summarization of all models on hemicellulose hydrolysis.The kinetics were caculated as following: The active energy of hemicellulose degradation were 65.58kJ/mol for xylan, 68.76kJ/mol for rice straw and 95.19kJ/mol for palm shell; The active energy of sugar degradation were 147.2kJ/mol, 47.08kJ/mol for rice straw and 79.74 for palm shell. The caculated results meet approximately with the experiment data. Based on the data of batch experiments, with combination of summarization on the hydrolysis reactor styles, a two-stage continuous reactor of a capacity of 20kg/h were scheme out.The first stage was a horizonal plug flow reactor which hydrolyzed hemicellulose with hot liquid water. The second stage used a vertical countercurrent bed to achieve high celluose conversion by extremely low acid hydrolysis. |
| 语种 | 中文 |
| 公开日期 | 2011-07-14 ; 2011-07-15 |
| 页码 | 67 |
| 源URL | [http://ir.giec.ac.cn/handle/344007/5812]  |
| 专题 | 中国科学院广州能源研究所 |
| 推荐引用方式 GB/T 7714 | 徐明忠. 高温液态水预处理木质纤维素类生物质的实验研究, The Study on Hot Liquid Hydrolysis of lignocellulosic biomass[D]. 广州能源研究所. 中国科学院广州能源研究所. 2008. |
入库方式： OAI收割
来源：广州能源研究所
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