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Influence of chlorine on methane oxidation
Yong Chi1, Bo Wang, Jianhua Yan
1Institute for Thermal Power Engineering, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China. chiyong@zju.edu.cn
Journal of Environmental Sciences (China)
|December 17, 2009
Summary
Adding chlorine to methane oxidation enhances methane destruction but can increase toxic byproducts like phosgene (COCl2) at lower temperatures, impacting hazardous waste incineration efficiency.
Area of Science:
- Chemical Engineering
- Environmental Science
- Combustion Chemistry
Background:
- Hazardous waste incineration requires efficient destruction of hydrocarbons like methane (CH4).
- The role of chlorine in modifying hydrocarbon oxidation pathways is crucial for process optimization.
Purpose of the Study:
- To investigate the influence of chlorine on methane oxidation in a simulated hazardous waste incineration environment.
- To determine the effect of varying chlorine-to-hydrogen ratios (Cl/H) and temperatures on product formation and destruction efficiency.
Main Methods:
- Experiments were conducted in an atmospheric pressure flow reactor.
- Methane oxidation was studied across temperatures from 973 to 1273 K.
- Inlet Cl/H ratios ranged from 0 to 0.44, with online species analysis using Fourier transform infrared spectroscopy (FT-IR).
Main Results:
- Methane destruction and removal efficiency increased with higher Cl/H ratios.
- Increased Cl/H favored the formation of phosgene (COCl2) and carbon monoxide (CO), while inhibiting CO oxidation.
- Elevated temperatures enhanced CH4 destruction and reduced chlorinated intermediate concentrations (CH3Cl, CH2Cl2).
- CO and COCl2 concentrations peaked around 1100 K and 1023 K, respectively, before declining.
Conclusions:
- Chlorine addition enhances methane destruction efficiency in incineration.
- Incomplete combustion products, such as COCl2, are favored at insufficient temperatures, posing environmental and safety concerns.
- Optimizing temperature and Cl/H ratio is critical for effective and safe hazardous waste incineration.
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