scholarly journals Supercritical water oxidation of octol – containing wastewater

2019 ◽  
Vol 21 (2) ◽  
pp. 172-179 ◽  
Keyword(s):  
Supercritical Water ◽  
Water Oxidation ◽  
Reaction Times ◽  
Pilot Scale ◽  
Operating Conditions ◽  
Performance Criteria ◽  
Optimum Operating ◽  
Toxicity Tests ◽  
Supercritical Water Oxidation ◽  
Product Analysis

<p>This study investigated optimum operating conditions of supercritical water oxidation (SCWO) for octol and compared the degradation of its components TNT (2,4,6-trinitrotoluene) and HMX (octahydro-1,3,5,7- tetranitro-1,3,5,7-tetrazocine, octogen) under the same conditions. Pilot scale experiments were conducted at various temperatures, reaction times and oxidant amounts. Removal efficiency, by-product analysis and toxicity tests were selected as the performance criteria for the SCWO. Optimum conditions were determined as a temperature of 500 C, 120 s of oxidation time and an oxidant ratio of 150%. Removal of octol was achieved at a rate of 99.99%, while TNT and HMX were removed individually at a rate of ~85% when they existed in the wastewater. No toxicity was observed at the end of the octol oxidation, whereas toxicity was found in the TNT and HMX oxidation due to the formation of TNT isomer and aniline. Higher initial organic material concentrations promoted the removal rates. These results demonstrated that SCWO can be effectively used for the degradation of ammunition wastewater even when concentrations are high.</p>

Supercritical Water Oxidation – Wastewaters and Sludges

1991 ◽  
Vol 23 (1-3) ◽  
pp. 389-398 ◽  
Author(s):  
Abdullah Shanableh ◽  
Earnest F. Gloyna
Keyword(s):  
Acetic Acid ◽  
Supercritical Water ◽  
Water Oxidation ◽  
Biological Treatment ◽  
Treatment Plant ◽  
Transformation Products ◽  
Pilot Scale ◽  
Supercritical Water Oxidation ◽  
Temperature And Pressure ◽  
Dimethyl Phenol

Environmental contaminants can be eliminated through the use of SCWO techniques. A comprehensive supercritical oxidation (SCWO) research laboratory, including bench and pilot-scale facilities has been developed. High temperature and pressure systems slightly less than and greater than supercritical water conditions can be used for the efficient destruction of waste biological treatment plant sludges, acetic acid, 2-nitro phenol, 2,4-dimethyl phenol, phenol, and 2,4-dinitro toluene. Above 400 °C, near complete destruction of sludge and transformation compounds such as acetic acid can be achieved with relatively short residence times. Ammonia and acetic acid are transformation products in the SCWO of biological treatment plant sludges. Acetic acid produced from the oxidation of sludge is oxidized rapidly at supercritical temperatures, 400 °C to 450 °C.

Simulation of Supercritical Water Oxidation with Air at Pilot Plant Scale

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Belén García Jarana ◽  
Jezabel Sánchez Oneto ◽  
Juan Ramón Portela Miguélez ◽  
Enrique Nebot Sanz ◽  
Enrique J. Martínez de la Ossa
Keyword(s):  
Kinetic Parameters ◽  
Supercritical Water ◽  
Water Oxidation ◽  
Pilot Plant ◽  
Reaction Kinetic ◽  
Pure Water ◽  
Kinetic Equations ◽  
Pilot Scale ◽  
Laboratory Scale ◽  
Supercritical Water Oxidation

Supercritical Water Oxidation (SCWO) processes have been studied by numerous researchers. The effectiveness of this approach to treat a wide variety of wastes has been proved and the kinetics involved in some cases have been described. Phenol is commonly present in industrial wastewaters and it is extremely toxic. Hence, phenol is a model pollutant that has been the subject of numerous studies by SCWO on a laboratory scale. In this work, a pilot-scale SCWO system has been used to compare experimental and predicted conversions in the SCWO of phenol, using the reaction kinetic equations obtained at the laboratory scale. In this context, “PROSIM PLUS” software was employed to develop a simulator for the pilot plant facility, with the reaction kinetic parameters adjusted to represent the experimental data. In this study it was necessary to determine the thermal losses between the experimental reactor and its surroundings. These thermal losses were obtained from tests with pure water and oxidant streams in the absence of chemical reaction. An equation that predicted the effect of flow rate and temperature on the thermal losses was used. Experimental oxidation tests were conducted with initial temperature in the range 380 to 425 ºC, at 250 bar and phenol concentrations ranging from 1 to 12 g/l. Good agreement in the simulation was obtained by adjusting the kinetic parameters within their confidence range. This simulator was used to optimize the SCWO of phenol solutions in the pilot plant facility.

Supercritical water oxidation of sludges contaminated with toxic organic chemicals

2000 ◽  
Vol 42 (7-8) ◽  
pp. 363-368 ◽  
Author(s):  
N. Crain ◽  
A. Shanableh ◽  
E. Gloyna
Keyword(s):  
Supercritical Water ◽  
Water Oxidation ◽  
Paper Mill ◽  
Pilot Scale ◽  
Supercritical Water Oxidation ◽  
Pulp And Paper Mill ◽  
Remediation Technology ◽  
University Of Texas ◽  
The University ◽  
Hazardous Compounds

Supercritical water oxidation (SCWO) is a proven technology for the treatment of contaminated organic wastes. Bench and pilot-scale work completed at The University of Texas at Austin's SCWO Laboratory have proven the technology effective for treating a variety of sludge types, including sludge contaminated with hazardous compounds. The studies included pulp and paper mill sludges and sludges derived from the treatment of municipal and industrial wastewaters. The results presented in this paper confirmed that the removal of the organic component of sludge, including the trace toxic organic compounds, using SCWO exceeded 99.9%. For example, the results show that the destruction removal efficiencies (DRE's) of the PCBs reached 99.99% in the contaminated sludge. No dioxins or furans were detected in the gaseous effluent resulting from the treatment of the PCB-contaminated sludge. These results demonstrate the technical effectiveness of SCWO as a sludge remediation technology.

Design of the first pilot scale plant of China for supercritical water oxidation of sewage sludge

2012 ◽  
Vol 90 (2) ◽  
pp. 288-297 ◽  
Author(s):  
Donghai Xu ◽  
Shuzhong Wang ◽  
Xingying Tang ◽  
Yanmeng Gong ◽  
Yang Guo ◽  
...  
Keyword(s):  
Sewage Sludge ◽  
Supercritical Water ◽  
Water Oxidation ◽  
Pilot Scale ◽  
Supercritical Water Oxidation

Modeling and simulation of hydrothermal oxidation of cutting oil in supercritical water

2020 ◽  
Vol 18 (8) ◽  
Author(s):  
Nadjiba Benmakhlouf ◽  
Nawel Outili ◽  
Jezabel Sánchez-Oneto ◽  
Juan Ramon Portela ◽  
Abdeslam Hassen Meniai
Keyword(s):  
Flow Rate ◽  
Supercritical Water ◽  
Water Oxidation ◽  
Initial Temperature ◽  
Operating Conditions ◽  
Outlet Temperature ◽  
Treatment Technique ◽  
Supercritical Water Oxidation ◽  
Feed Concentration ◽  
Dependent Variables

AbstractSupercritical water oxidation may be used as waste treatment technique that consists of oxidizing organic and inorganic matter using water at supercritical conditions. It was developed as an alternative technique in order to limit the risks of secondary pollution. The purpose of this study is the development of simulation tools in stationary state in supercritical water oxidation (SCWO) tubular reactor which has been numerically investigated basing on using a two-dimensional modeling approach applying the k-ε turbulence model, and on the international association for the properties of water and steam formulation (IAPWS-IF97). A Multiphysics simulation using Comsol Multiphysics 5.2 software for the supercritical water oxidation of “cutting oil Biocut 35” as a pollutant is reported. First, the heat transfer coefficient was estimated and the obtained temperature and species concentration profiles were compared to experimental data where a quite good agreement was obtained as confirmed by the acceptable coefficient of determination value. Finally, once the used model was validated, numerical simulations were performed to describe the behavior of the reactor investigating the effects of operating conditions such as temperature, pollutant feed concentration and reactor inlet flow rate, on dependent variables like outlet temperature, chemical oxygen demand removal (COD) and the highest temperature reached inside the reactor. This last parameter was considered in the study to take into account the operation safety. The significance of the studied factors and their interactions were quantified and analyzed by means of the full factorial design of experiment (DOE). The results showed that the effect of initial temperature was the most important for the three responses, followed by the feed concentration then to a lesser extent the flow rate. The effect of initial temperature was positive for outlet temperature, maximal temperature and cutting oil removal. The interaction temperature-feed concentration was the only significant one for the COD removal and the maximal temperature. The results defined an operation safety zone of the SCWO reactor based on the superposition of the three studied dependent variables and imposed constraints on the inside reactor temperature and the pollutant outlet concentration.

Treatability of Phenol by Supercritical Water Oxidation

2011 ◽  
Vol 422 ◽  
pp. 462-465
Author(s):  
Hui Li ◽  
En Zhao
Keyword(s):  
Supercritical Water ◽  
Water Oxidation ◽  
Continuous Flow ◽  
Flow Reactor ◽  
Reaction Times ◽  
Supercritical Water Oxidation ◽  
Continuous Flow Reactor ◽  
Organic Destruction ◽  
Water Conditions ◽  
Phenol Wastewater

This study focused on the treatment of phenol wastewater by supercritical water oxidation(SCWO). Tests were conducted by using a continuous-flow reactor system. Based on COD, organic destruction efficiencies of phenol wastewater were obtained at supercritical water conditions. Temperatures and pressures, respectively, ranged from 400-500°C,and 25-40Mpa. The reaction times varied from 30 to 190 seconds, and hydrogen peroxide was used as oxidant. Under SCWO conditions, destruction efficiencies greater than 99% were achieved.

scholarly journals Naphthalene mineralization by supercritical water oxidation and determination of by-products using Non-target analysis

2021 ◽  
Author(s):  
H. Ates ◽  
M. E. Argun ◽  
N. Kurt
Keyword(s):  
Supercritical Water ◽  
Water Oxidation ◽  
Oxidation Process ◽  
Operating Conditions ◽  
Supercritical Water Oxidation ◽  
Experimental Conditions ◽  
Design Program ◽  
Derivatives Of ◽  
By Products

Abstract In this study, the fate of naphthalene was investigated with a supercritical water oxidation process (SCWO). Also, the effectiveness of different operating conditions including pressure, temperature, residence time and oxidant dose on the formation of by-products were determined. The experimental sets were determined by the experimental design program and the effect of the selected variables on the removal of the naphthalene was associated statistically. According to obtained results, naphthalene by SCWO process was mineralized up to 98.5%. Removal efficiencies in sub- and supercritical conditions were determined as between 94 and 100%. Derivatives of aldehyde, propanoic acid, benzene acetic acid and benzofuran were detected as by-products at many experimental conditions and also, some intermediates with a molecular weight higher than naphthalene were determined.

Sign in / Sign up

Export Citation Format

Share Document