Development of an inverse diffusion partial oxidation flame and model burner contributing to the development of 3rd generation coal gasifiers

Gasification by partial oxidation of coals is a key process for the chemical and power industry. Hence, studying these reactions is of major interest. In order to investigate partial oxidation phenomena on a simplified laboratory scale, a reference flame for partial oxidation (POX flame) is developed and characterized. Such a flame consists of a high-temperature oxidation zone and the subsequent low-temperature post-flame region, which both represent conversion zones of large-scale gasifiers in principle.The scope of this paper is to determine the influence of different fuel dilutions on the elementary composition, the exit temperature and the kinetics occurring in this flame and thus to find the best configuration for investigating partial oxidation reactions. Further, thermo-chemical phenomena in the flame zone and the post-flame zone are investigated both experimentally and numerically. For this purpose, a literature flame was used to validate the experimental and numerical setup. Subsequently, the final burner setup was investigated in detail. The developed laminar inverse diffusion flame with pure oxygen as oxidizer, a 1:1 molar mixture of methane and carbon dioxide as fuel at an equivalence ratio of 2.5 represents well the conversion reactions in the post-flame zone.

► A reference flame is developed for studying gas-phase reactions in gasification. ► A CH4/CO2 fuel mixture with pure O2 suits most to reflect for gasification. ► Experimental investigations applying OH LIF were carried out. ► CFD results with detailed diffusion and chemistry agree well with experiments. ► The chosen fuel–oxidizer mixture passes through endothermic zones and is converted.