Wet combustion and its performance 232 .pdf pages
Thesis presented for obtaining the title of Doctor of the University Henri Poincaré, Nancy 1 Science in Mechanical and Energy. By Rémi Guillet.
Keywords: wet combustion / combustion / humidity / hygrometry / environment / efficiency / energy / thermal process / nitrogen oxides / protection
For many years, water has been used as an additive to improve combustion, power machinery, or as an octane and more recently as inert for reducing the formation of nitrogen oxides. Today the challenge for the economy of the scarce resource of fossil fuels and more, the protection of the environment.
With the wet combustion, the performance of land based gas turbines can be enhanced very significantly Thus, steam injection cycles (STIG), regenerative cycles to humidified air (HAT), can approach the performance of the combined cycle.
For its part, the steam pump cycle that recycles the ultimate heat, sensible and latent, usually discharged into the chimney, the form of air preheated combustion and humidified, allows many processes to approach performance maximum combustion 100% of the gross calorific value of the fuel.
In all its forms, the introduction of water into the combustion chambers is also known to reduce NOx formation: direct injection, emulsion with the fuel in vapor form generated by a catcher, a steam pump ...
So remarkable energy and environmental performance are possible,
especially for processes that enhance the recovery of latent heat. Among the most likely to benefit from the advantages of the wet combustion processes, of:
- Condensing boilers;
- Generators in direct contact;
-The live dryers with energy recovery;
- Regenerative turbine cogeneration;
-the methods of clean incineration with energy recovery.
Wet combustion, three fluids are introduced into the combustion chamber: the fuel, combustion air and additional water ...
To analyze these processes, we have developed a method of analysis using the
wet bulb temperature as the main parameter, called Diagram of Hygrometric
Combustion. This method, described in detail and numerous diagrams derived therefrom, is recommended for:
-analysis, forecasting, improvement, optimization of combustion efficiency;
- Predictive control;
- The prediction of condensation;
- The dimensioning of the biphasic exchangers.
But the method can also be used in the case of conventional methods such as condensing boilers and generators to provide access to performance prospects more accurately and at lower cost.
Further information about the changes due to the presence of additional water in thermal processes with combustion are also provided.