纤维素原料预处理技术的过程工程研究及系统评价

项目名称： 纤维素原料预处理技术的过程工程研究及系统评价

项目编号： No.20876078

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 环境科学、安全科学

项目作者： 张红漫

作者单位： 南京工业大学

项目金额： 32万元

中文摘要： 木质纤维素原料转化成生物质糖，在此基础上生产生物能源及生物基化学品对环境保护和经济社会的可持续发展具有重要意义，是目前国内外研究的热点。而在纤维素原料的转化过程中，预处理过程是十分关键的步骤。本课题以纤维素原料玉米秸秆为研究对象，创新性地提出了一套稀酸循环喷淋预处理工艺，该过程能很好地降解半纤维素使木糖得率高而发酵抑制物少，同时由于处理过程中木质素的有效去除，使处理后物料的酶解效率显著提高；结合扫描电镜、热重分析、红外光谱及X-射线衍射等现代分析手段的表征结果，解析了预处理过程中纤维素原料在复杂流体系统中的反应机理及解聚机制，建立了反应动力学模型；以纤维素酶解效率为评价指标，对典型的球磨预处理工艺过程进行了系统评价及工艺优化，同时对蒸爆、螺杆挤压等十种预处理工艺进行了酶解评价；创新性地成功开发了GC/MS直接进样分析模式，实现了玉米秸秆酸性水解液中18种发酵抑制物的定性定量分析，并对酶解糖液的发酵性能进行了初步评价；设计制作了适用于高底物浓度酶解的新型卧式酶解反应装置，并对酶解反应体系进行了流变学分析，利用计算流体力学对反应过程进行了模拟。

中文关键词： 木质纤维素; 预处理; 动力学; 酶水解; 系统评价

英文摘要： The conversation process of lignocellulosic biomass to sugar that uses as a basis for the production of bionenergy and bio-based chemicals becomes the hot research area all around the world, which is significant for environmental protection and social and economic sustainable development. Pretreatment is essential in the bioconversion of lignocellulosics to useful products. In this project, a typical cellulosic material corn stover was investigated, and a novel pretreatment system, dilute acid cycle spray flow-through (DCF) had been presented. In the course of DCF, the hemicelluloses could be effectively degraded with high xylose monomer yields and low contents of fermentation inhibitors, while the enzymatic digestibility had been enhanced due to the effective lignin removal in this process. The reaction and depolymerized mechanism of lignocellulosics was analyzed combining with the results of SEM, TGA, IR and XRD, which provided theoretical foundatoin for the establishment of dynamic model. Meanwhile, a typical ball milling pretreating process had been evaluated and optimized in term of enzymatic hydrolysis efficiency of cellulose. Furthermore, a novel GC/MS analytic model with direct aqueous injection was developed, which identified and quantified 18 kinds of fermentation inhibitors in dilute acid hydrolysate, and the fermenting performance of sugar hydrolysate were assessed. On the other hand, the rheologic properties of reaction system of enzymatic hydrolysis had been analyzed based on the construction of a new-type reactiontor for enzymatic hydrolysis with high substrate concentration, and the reaction processes had been simulated by computational fluid dynamics.

英文关键词： lignocellulosics; pretreatment; dynamics; enzymatic hydrolysis; system evaluation