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Abstract: This work is connected with properties of a flame obtained by combustion of liquified propane gas (LPG) with highly preheated air using a regenerative burner. The attention is focused on both the size and shape of the flame and the results were obtained in a semi-industrial furnace equipped with a regenerative burner system. Results of the CFD-based mathematical modeling have been compared with measurements of a number of parameters including the furnace-wall temperature and the concentrations of gaseous species in the furnace. The results indicate that the flame spread can be well predicted using the numerical model. A flame entrainment ratio has been proposed here for describing and classifying the physical changes of the flame shape. This ratio can be used to optimize the diameter and length of a combustion chamber for specific applications. It is also found that equipping a furnace with a regenerative burner can provide a high saving energy, a larger flame volume and a lower emission of NO. It has been obtained that a lower excess air ratio leads to a low peak temperature and a larger flame volume, thus a lower NO emission. [Copyright &y& Elsevier]

In a biomass gasification process, condensation of inorganic species can cause problems such as corrosion and deposition on the downstream equipment. In this work, in order to investigate the condensation of inorganics during the gas cooling step of the biomass gasification system, both experimental and modelling studies were conducted. Experiments were performed on a pilot-scale steam/oxygen blown fluidized bed gasification facility. A CO 2 cooled probe was located at the head of a filter to condense inorganic species. Five thermocouples were used to monitor the probe temperature profile. Deposits on the probe were characterized using scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) to analyze the elemental composition of deposits. A process model based on the local chemical and phase equilibriums was developed using software SimuSage to predict both release and condensation of inorganics. A customized thermodynamic database extracted from the FactSage 7.1 was used during model calculations. Two cases including with and without addition of bed material were calculated. Results show that the identified elemental compositions of deposit under different gas cooling temperatures reasonably agree with the elemental compositions predicted by model calculations. This demonstrates that the established model and the customized thermodynamic data are valid. A large amount of carbon is identified in the deposit of low temperature probe sections, which may come from the condensed tar. Additionally, a temperature window is found, where melts are formed during gas cooling. [ABSTRACT FROM AUTHOR]