摘要
深低温区的汽液相平衡实验研究在化工和能源等各领域具有重要作用,其数据也是专业数据库热衷于搜集的对象。论文自行研制了一种用于测量深低温区汽液相平衡数据的高精度实验装置。实验装置主要由恒温系统与测量系统组成,即包括不锈钢平衡釜、控温温度测量系统、真空及配气系统等,恒温浴中的冷量由液氮提供。在恒温浴中,温度达到平衡后其波动小于±5 mK(30 min)1。温度测量采用四线制标准铂电阻温度计,其型号为WZPB-I,China,不确度为±1 mK(ITS),数据采用Keithley 2002多功能万用表进行采集,温度总的不确定度为±10 mK,压力采用压力传感器(型号:PMP4010,Drunk)进行测量,总的压力的不确定度为±330 Pa。此外以Visual BASIC为开发平台,为实验台设计并开发了一套集实时数据采集、自动控制、存盘记录和数据分析处理于一体的测控软件。通过实验装置初步测试,测试结果显示实验装置运行良好,实验数据与参考数据具有良好的一致性,可以满足实验要求,且所开发的软件方便实用,明显提高了实验测试的自动化水平,有力保障了混合工质相平衡实验工作的顺利进行。
The experimental study of VLE at low temperature is important in the chemical engineering, energy engineering, etc., and its experimental results are always accepted by professional database. In this paper, an experimental apparatus with high accuracy is developed to get the VLE data at low temperatures. The apparatus consists of the stainless steel equilibrium cell, the temperature control system and measurement system, etc.. The temperature of the thermostat bath is maintained by liquid nitrogen and a heating coil. The temperature fluctuation in the bath is less than ±5 mK.（30 min）-1. The temperature is measured by a four-head 25-platinum resistance thermometer （Model： WZPB-I, China） with an uncertainty of ±1 mK （ITS） and a Keithley 2002 data acquisition/switch unit. The overall uncertainty of the measured temperature is within 4-10 mK. The pressure is measured by a pressure transducer （Model： PMP4010, Drunk）. The total uncertainty of the pressure measurement is within 4-330 Pa. In addition, based on Visual BASIC, a measurement and control program is also developed to get on-time data logging. The experimental VLE data of the methane and nitrogen mixture obtained by using the developed apparatus were compared with the corresponding reference data, and they have a good agreement with each other. The operating results show that the experimental apparatus developed runs well.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2012年第6期917-922,共6页
Journal of Chemical Engineering of Chinese Universities
基金
国家自然科学基金(50806063)
浙江省自然科学基金(Y1090455)
关键词
深低温
汽液相平衡
实验装置
天然气
cryogenics
vapor-liquid equilibrium
experimental apparatus
natural gas
