An automatic monitoring technique for water-soluble inorganic particles

• Main Author: 劉怡伶
• Other Authors: 蔡春進
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/wktxne

碩士 === 國立交通大學 === 環境工程系所 === 101 === In this study a real-time monitoring system, PPWD-WEP, which consists of parallel plate wet denuder (PPWD), wet electrostatic precipitator (WEP) and ion chromatography (IC) for soluble inorganic acid/basic air and particles sampling, was developed. The present system can solve the problems in traditional sampler such as time consuming and artificial generated during samples transportation and analysis. It is expected that the convenience and accuracy of air sampling and analysis can be enhanced by the present system. In the PPWD-WEP, porous glass plate and copper plate which are coated with TiO2 nanoparticles to enhance the hydrophilicity are used as the acting surfaces and the collection electrode, respectively. The soluble inorganic acid/basic air and particles are collected by a uniform water film flowing downward along the active and collection electrodes surface. Ion chromatography is used to analyze liquid samples. NH3 and HF gases generated by a gas generator were used as the test gas and sampled by PPWD-WEP system without applying to high voltage and impinger at the same time. The gas concentrations sampled by PPWD-WEP system agree well with those sampled by impinge with deviation lower than 4.4%. The PPWD-WEP system applied to high voltage and filter sampler were further used to sampled NaCl and (NH4)2SO4 particles simultaneously, which were produced by atomizer (TSI, Model 3076) in this study. In the PPWD-WEP system, particles migrated to the collection electrodes because of the electrostatic force and then collected by scrubbing liquid. Particles collected by filters were extracted by used deionized water. Ion Chromatograph was used to analyze the samples and determined the ion concentration in the particles. The results show that when the sodium ion and chloride concentrations were 0.93-36.46μg/m3 and 0.83-48.8 μg/m3, respectively, the concentrations measured by the present system agree well with those sampled by filter samplers with deviation lower than □10.7 %. When sulfate and ammonium concentrations were 1.25-16.2 μg/m3 and 0.55-6.58 μg/m3, respectively, the concentrations sampled by the present system are in good agreement with those sampled by filter samplers with a deviation lower than □5~20%. This result suggested that the present PPWD-WEP system can be used to monitor inorganic acid /basic gases and NaCl and (NH4)2SO4 particles accurately.