Decontamination of Simulated Wastewater Containing Acetic Acid by Continuous Supercritical Water Oxidation

• Main Authors: Hung-Chih Wang, 王鴻志
• Other Authors: none
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/28653783493532462527

碩士 === 逢甲大學 === 環境工程與科學所 === 93 === Supercritical water oxidation (SCWO) represents an innovative technology for its complete and efficient characteristic to the destruction of hazardous waste without generation of harmful by-products. Organic compounds and oxygen are completely soluble in water above its critical point of 374℃ and 218atm, which provides a single-phase medium for rapid oxidation of organic to CO2 and H2O with the destruction removing efficient (DRE) over 99% in a short residence time. In the past decade, Japan, America and Europe countries prompted research to develop the SCWO technology. The major difficulty in SCWO was the mineralization of organic matter a large amount of inorganic salts and sludge were formed. The generated salts could block the tube and therefore limited the operation applications. When the oxygen and reaction temperature are not high enough, organic matter in SCWO may possibly produce the intermediary product, such as formic acid and acetic acid etc. Acetic acid is stable in aqueous solution and is not easily degraded. In this thesis, studies will focus on the decontamination of acetic acid by continuous SCWO technology and establish operation parameters for the destruction of acetic acid in SC water. The reactor’s pressure maintains at 250 atm and at 460 ℃, the DRE of TOC and COD for simulated acetic acid solution reaches approximately 50% and the changes of pH is very small. According to our experimental results, in order to complete destruction of acetic acid, either raise the reaction temperature or a burning agent such as ethylene glycol must be added to the solution to enhance the DRE.