Developing of experimental combustion boiler with stationary fluidized bed and multifuels combustion

Due to the outdated higher requirements for reducing emissions of harmful substances in the combustion of fossil fuels and waste in particular, more and more research is needed, which will lead to the provision of various alternatives to influence the emerging pollutants into the atmosphere. This study deals with the development of experimental combustion units with a stationary fluidized bed with regulated parameters of primary and secondary air supply, performed fuel supply and flue gas parameters. Combustion is carried out in a bubbling stationary fluidized bed with a height of 100 mm and a diameter of 140 mm. The fluidized bed consists of ST 54 glass sand with a mean grain size of 0.22 mm. The basic purpose of the study is to describe the construction of the experimental unit with verification of its functionality. On the experimental equipment was realized experiments in terms of combustion various types of fuels, whether they are fossil fuels (coal), alternative fuels as straw pellets, sludge from wastewater treatment plants, sludge from paper mills or their combinations. Determination of temperature and pressure along the entire length of the unit is a device equipped with thermocouples and pressure sensors.

Experimental combustion chamber simulation at transient regimes

The transient regimes in a combustion chamber has to be as short as possible because flame front position and thickness can destroy the combustion chamber in couple seconds. The simulation of such a regime has to be performed unsteady. An experimental combustion chamber it is simulated at two unsteady regimes to see the flame front structure and comparison it is made with the experimental data to validate the results. For this analysis Ansys CFX was used and the turbulent model was DES while the combustion model was Eddy Dissipation. The two cases show different flame front structures while the boundary conditions for the two regimes are very similar.

Impact of oxygen enhanced combustion of natural gas on thermal efficiency of combustion aggregate

The aim of the present article is to present the achieved results on the experimental combustion aggregate. In the experimental measurement, the increased of the oxygen concentration in the oxidizing agent in the combustion of natural gas has been used. The results presented in this article are focused to achieve the thermal efficiency of the device, which is expressed by useful heat of the combustion aggregate. Part of the article is the analysis of the heating heat exchanger based on heat flow by convection and radiation and CFD mode of heat exchanger