Journal of Hazardous Materials, Vol.137, No.2, 965-971, 2006
Destruction of an industrial wastewater by supercritical water oxidation in a transpiring wall reactor
The supercritical water oxidation (SCWO) is a technology that takes advantage of the special properties of water in the surroundings of critical point of water to completely oxidize wastes in residence times lower than I min. The problems caused by the harsh operational conditions of the SCWO process are being solved by new reactor designs, such as the transpiring wall reactor (TWR). In this work, the operational parameters of a TWR have been studied for the treatment of an industrial wastewater. As a result, the process has been optimized for a feed flow of 16 kg/h with feed inlet temperatures higher than 300 degrees C and transpiring flow relation (R) between 0.2 and 0.6 working with an 8% (w/w) isopropanol (IPA) as a fuel. The experimental data and a mathematical model have been applied for the destruction of an industrial waste containing acetic acid and crotonaldehyde as main compounds. As the model predicted, removal efficiencies higher than 99.9% were obtained, resulting in effluents with 2 pprn total organic carbon (TOC) at feed flow of 16 kg/h, 320 degrees C of feed temperature and R = 0.32. An effluent TOC of 35 ppm under conditions feed flow of 18 kg/h, feed inlet temperatures of 290 degrees C, reaction temperatures of 570 degrees C and R = 0.6. (c) 2006 Elsevier B.V. All rights reserved.
Keywords:supercritical water oxidation;SCWO;transpiring wall reactor;acetic acid;crotonaldehyde;industrial waste