不同豆腐废水添加量下芦苇秆水热焦燃烧特性研究  

Fuel Characteristics of Reed Stalk Hydrochar under Different Dosages of Bean Curd Wastewater

作　　者：郭淑青 董向元 陈祥 王树中 高新杰 张恒瑞 GUO Shuqing;DONG Xiangyuan;CHEN Xiang;WANG Shuzhong;GAO Xinjie;ZHANG Hengrui(School of Energy and Power Engineering,Nanjing Institute of Technology,Nanjing 211167,China;School of Energy and Environment,Zhongyuan University of Technology,Zhengzhou 450007,China)

机构地区：[1]南京工程学院能源与动力工程学院,南京211167 [2]中原工学院能源与环境学院,郑州450007

出　　处：《农业机械学报》2021年第3期325-330,共6页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金项目(51206194);南京工程学院引进人才科研启动基金项目(YKJ201811、YKJ201812)。

摘　　要：为研究豆腐废水添加量对生物质水热碳化行为的影响,以芦苇秆为原料,纯水溶剂为参照,在反应温度250℃、停留时间240 min、液固比5~30条件下进行了水热碳化实验,分析了水热焦元素组成和燃烧特性的变化规律。结果表明,随着液固比的增加,豆腐废水溶剂中水热焦产率从49.27%增至63.53%,而纯水溶剂中水热焦产率从46.30%下降至38.30%,两者变化趋势相反;豆腐废水中水热焦的C和N质量分数变化范围分别为68.35%~70.30%和1.48%~3.26%,高于纯水中水热焦的相应参数,且随着液固比增加,豆腐废水中水热焦的C和N质量回收率增加;豆腐废水促进了芦苇秆的脱羧反应,水热焦H/C原子比和O/C原子比均与褐煤相近,高位热值最高为29.53 MJ/kg,能量密度约为1.80,能量回收率从0.85增至1.17,而燃料比从1.09减小至0.78。在液固比不大于10时,豆腐废水溶剂中的芦苇秆水热焦有与纯水溶剂水热焦相近的燃烧特性,其燃烧性能良好。Bean curd wastewater(BCW)is the main waste in the processing of bean products.It is expected to save water resources and reutilize the organic matter in BCW by using BCW instead of pure water as reaction solvent of hydrothermal carbonization(HTC).However,the mechanism of the effect of BCW on the HTC remained unknown.To investigate the effect of different BCW dosages on the HTC of biomass,the HTC experiments of reed stalk under BCW and pure water were carried out at 250℃for 240 min at liquid-solid ratio of 5~30.The elemental composition and fuel characteristics of hydrochar were analyzed in depth.The results showed that with the increase of liquid-solid ratio,the yield of hydrochar obtained under the BCW was increased from 49.27%to 63.53%while that obtained under the pure water was decreased from 46.30%to 38.30%.The C and N content of hydrochar obtained under the BCW was 68.35%~70.30%and 1.48%~3.26%respectively,which was higher than the corresponding parameters of hydrochar obtained under pure water.Moreover,the C and N recovery efficiency of hydrochar obtained under the BCW was increased as the liquid-solid ratio was enhanced.The BCW promoted the decarboxylation reaction during hydrothermal carbonization of reed stalk.Both H/C and O/C atomic ratios of hydrochar obtained under the BCW were close to those of lignite.The higher heating value(HHV)of hydrochar was up to 29.53 MJ/kg.The energy densification was about 1.80.And the energetic recovery efficiency of hydrochar was increased from 0.85 to 1.17,while the fuel ratio of hydrochar was decreased from 1.09 to 0.78.When the liquid-solid ratio was less than 10,the combustion characteristics of hydrochar under the BCW were similar to those of hydrochar obtained under pure water,indicating good combustion performance for hydrochar.Thus,the liquid-solid ratio of BCW and biomass should be less than 10 when hydrochar was used as fuel.

关 键 词：芦苇秆 水热焦 豆腐废水 生物质 水热碳化 燃烧 

分 类 号：S216[农业科学—农业机械化工程]