Supercritical water oxidation of landfill leachate

Journal Article · Thu Sep 15 00:00:00 EDT 2011 · Waste Management

DOI:https://doi.org/10.1016/j.wasman.2011.05.006· OSTI ID:21578473

Yang, Guo ^[1]; Chongming, Chen ^[2]; Jie, Zhang; Yanmeng, Gong; Yuzhen, Wang ^[1]

---

1. School of Energy and Power Engineering of Xi' an Jiao Tong University, Xi'an 710049 (China)
2. Hebei Electric Power Research Institute, Shijizhuang, Hebei 050021 (China)

Highlights: > Thermal analysis of NH{sub 3} in supercritical water oxidation reaction. > Research on the catalytic reaction of landfill leachate by using response surface method. > Kinetic research of supercritical water oxidation of NH{sub 3} with and without MnO{sub 2} catalyst. - Abstract: In this paper, ammonia as an important ingredient in landfill leachate was mainly studied. Based on Peng-Robinson formulations and Gibbs free energy minimization method, the estimation of equilibrium composition and thermodynamic analysis for supercritical water oxidation of ammonia (SCWO) was made. As equilibrium is reached, ammonia could be totally oxidized in SCW. N{sub 2} is the main product, and the formation of NO{sub 2} and NO could be neglected. The investigation on SCWO of landfill leachate was conducted in a batch reactor at temperature of 380-500 deg. C, reaction time of 50-300 s and pressure of 25 MPa. The effect of reaction parameters such as oxidant equivalent ratio, reaction time and temperature were investigated. The results showed that COD and NH{sub 3} conversion improved as temperature, reaction time and oxygen excess increased. Compared to organics, NH{sub 3} is a refractory compound in supercritical water. The conversion of COD and NH{sub 3} were higher in the presence of MnO{sub 2} than that without catalyst. The interaction between reaction temperature and time was analyzed by using response surface method (RSM) and the results showed that its influence on the NH{sub 3} conversion was relatively insignificant in the case without catalyst. A global power-law rate expression was regressed from experimental data to estimate the reaction rate of NH{sub 3}. The activation energy with and without catalyst for NH{sub 3} oxidation were 107.07 {+-} 8.57 kJ/mol and 83.22 {+-} 15.62 kJ/mol, respectively.

• OSTI ID: 21578473
• Journal Information: Waste Management, Vol. 31, Issue 9-10; Other Information: DOI: 10.1016/j.wasman.2011.05.006; PII: S0956-053X(11)00248-0; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0956-053X
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ACTIVATION ENERGY
AMMONIA
CATALYSTS
EQUILIBRIUM
EXPERIMENTAL DATA
FREE ENTHALPY
MANGANESE OXIDES
NITRIC OXIDE
NITROGEN DIOXIDE
OXIDATION
OXIDIZERS
OXYGEN
PRESSURE RANGE MEGA PA
REACTION KINETICS
REFRACTORIES
SANITARY LANDFILLS
THERMAL ANALYSIS
WATER
CHALCOGENIDES
CHEMICAL REACTIONS
DATA
ELEMENTS
ENERGY
HYDRIDES
HYDROGEN COMPOUNDS
INFORMATION
KINETICS
MANAGEMENT
MANGANESE COMPOUNDS
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NITROGEN OXIDES
NONMETALS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
PRESSURE RANGE
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
WASTE DISPOSAL
WASTE MANAGEMENT