Low Emission Combustion of Vegetable Oils with the Porous Burner Technology
low NOx- and CO-emissions due to lower and controllable combustion zone temperatures,
wide, infinitely variable dynamic power range of 1:20 while conventional state of the art premixed burners show a power range of 1:4,
high power density of up to 4 MW/m2 and 40 MW/m3 under atmospheric pressure,
high combustion stability over a wide range of equivalence ratios.
Due to these outstanding properties, the porous medium burner technology is attractive for a wide range of applications. One of them is the combustion of C02- emission neutral vegetable oils. Vegetable oils contain an enormous variety and number of different molecules, so that complete evaporation or gasification without any residuals in premixed burners is a very challenging task. Thus, systematic studies of controlled vegetable oil evaporation were carried out to make vegetable oils available as a fuel for porous medium combustion. The main result of these studies is, that vegetable oil evaporation without any residuals is not possible, but there are operating windows with acceptable low residual levels. For the practical realisation of vaporisers a suitable cleaning procedure through at least partial oxidation was developed, which uses air oxygen for partial oxidation under elevated temperature. A porous medium burner was constructed, which contains two vaporisers, so that one vaporiser can be cleaned while the other provides vegetable oil vapour for burner operation. Thus, continuous operation of the system can be achieved by cleaning the vaporisers mutually from time to time.
KeywordsPorous medium burner vegetable oils evaporation vaporiser low emission combustion
Unable to display preview. Download preview PDF.
- 1.Nitsch J. Wege in eine zukünftige Energieversorgung (Ways to Future Energy Supply), Presentation, Energie Innovativ, Nuremberg, Germany. 1998.Google Scholar
- 2.Trimis D., Durst F., Pickenäcker O., Pickenäcker K. Porous Medium Combustion versus Combustion Systems with Free Flames, 2nd International Symposium on Heat Transfer Enhancement and Energy Conservation, ISHTEEC’97, Guangzhou, China. 1997.Google Scholar
- 3.Durst F., Keppler M., Weclas M. Air-Assisted Nozzle Applied to very Compact, Ultra-Low Emission Porous Medium Oil Burner, 3rd Workshop “Spray 97”, Lampoldshausen, Germany. 1997; 22–23.Google Scholar
- 5.Pan H. L., Pickenäcker O., Trimis D. Investigation of Heat Transfer in Highly Porous Media-Experimental Determination of Heat Conductivities and Equivalent Pore Diameters, Report LSTM 508/E, Institute of Fluid Mechanics at the University of Erlangen- Nuremberg, Erlangen, Germany, 2000.Google Scholar
- 6.Apfelbeck R., Gessner B. H., Widmann B. A., Pontius P. Verwendung von Rapsöl zu Motorentreibstoff und als Heizölersatz in technischer und umweltbezogener Hinsicht (Technical and Environmental Aspects of Rape Oil as a Fuel for Car Engines and Household Heating), Technische Universitat Miinchen, Bayerische Landesanstalt fur Landtechnik, reising-Weihenstephan. 1992.Google Scholar