规模化沼气工程总挥发酸与碳酸氢盐自动滴定装置  

Automatic Titrator for Measurement of Total Volatile Fatty Acids and Total Inorganic Carbon in Scaled Biogas Project

作　　者：吴树彪[1] 陈新颖[1] 刘良[1] 郭建斌[1] 董仁杰[1] 

机构地区：[1]中国农业大学农业部可再生能源清洁化利用技术重点实验室,北京100083

出　　处：《农业机械学报》2015年第9期217-222,166,共7页Transactions of the Chinese Society for Agricultural Machinery

基　　金：'十二五'国家科技支撑计划资助项目(2012BAD47B02);北京市科技计划资助项目(D141100001214001)

摘　　要：为及时有效地监测和预警厌氧发酵系统的运行稳定性,根据Nordmann滴定法的原理,设计了一种沼气工程厌氧发酵液总挥发酸(VFA)质量浓度和碳酸氢盐(TIC)质量浓度自动滴定装置。本装置以Lab VIEW为平台,可精确测定厌氧发酵液的VFA质量浓度和TIC质量浓度,并能够实现p H计自动标定、自动滴定与补液、生成实时滴定曲线、数据处理与存储等功能。利用该装置对人工配制的混合模拟样品溶液和实际沼气工程的猪粪厌氧发酵液进行滴定试验,结果表明:测定混合模拟样品溶液和实际厌氧发酵液VFA质量浓度和TIC质量浓度的相对标准偏差均在5%以内,结果重复性好,准确度和精密度均比手动滴定法高,可有效避免手动滴定人为误差,提高工作效率,降低劳动强度;装置在连续运行15 h条件下测定结果稳定,运行性能良好,该装置在沼气工程监测和预警方面具有推广价值。In order to monitor and early warn the operational stability of anaerobic fermentation system timely and effectively, an automatic titrator for monitoring total volatile fatty acids （VFA） and alkalinity in term of total inorganic carbon （TIC） concentration in scaled biogas project was designed following the principle of Nordmann titration method. The titrator was designed based on the LabVIEW software. It can not only accurately measure the concentration of VFA and bicarbonate alkalinity, but also achieve the functions of automatic pH meter calibration, automatic titration and rehydration, generating, displaying, storing titration data and curving in real-time, etc. with the support of the host application software. The titrator was tested for examining its properties by titrating the artificially prepared mixed analog sample solution and anaerobically digested pig manure slurry. The results showed that the achieved relative standard deviations of VFA and TIC concentration in both the mixed analog sample solution and the digested pig manure slurry were less than 5%, which were lower than those in manual titration and indicated a higher measurement accuracy. Additionally, it can effectively avoid man-made error in process of traditional manual titration, improve work efficiency and reduce labor intensity. Moreover, even in the continuous long run for 15 h, the titration results were stable, indicating titrator＇ s operational stability and good performance. The results indicated that the automatic titrator would have an important practical application value for the biogas project.

关 键 词：沼气工程 厌氧发酵 挥发性脂肪酸 碳酸氢盐 自动滴定 

分 类 号：S24[农业科学—农业电气化与自动化]