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Regenerative combustion technology has many advantages such as fuel saving, high combustion efficiency and low emission, and it has been widely used for large-scale furnaces. However, when regenerative combustion technology is adopted for small-scale furnaces, many technical problems occur. In this paper, a small-scale regenerative furnace with heat load of 70–80 kW and primary air coefficient of 1.00–1.60 was designed. It was found that the flame shifts from bright pale blue with faint rotating streamlines to yellowish transparent without apparent streamlines and to bright and transparent eventually. When main burners work stably, the temperature inside the furnace raises rapidly at first, and then the temperature increases steadily and fluctuates periodically. The highest temperature in the furnace can reach around 1300 °C. As the reversing time increases, the temperature fluctuation becomes more dramatically and the highest temperature is higher. NOx concentrations at all measurement points are below 50 ppm. Heat transfer efficiencies of each heat retainer show an increasing trend with the rise of the number of reversions. As reversing time increases, the heat transfer efficiency shows a decreasing trend.

The exhaust gas temperature of SOFC is as high as 600–1000 °C and contains combustible components that can be reused. In this paper, an experimental system was set up to study the combustion characteristics of SOFC simulated exhaust gas in a porous medium burner, the combustion of SOFC exhaust gas under different equivalence ratio, the effects of hydrogen concentration and water vapor fraction in the anode exhaust gas and the stable combustion limits of the burners had been analyzed. Results showed that: equivalence ratio and adiabatic flame temperature had a significant effect on the combustion, when the adiabatic flame temperature of mixed gas below 440 °C, or the water vapor content in the anode gas was greater than 85%, the flame couldn’t be stably burned; On the condition of the fuel utilization rate of 60% and the equivalence ratio of 0.40, the burner could burn stably with the inlet airflow velocity from 0.16 to 0.24m/s; The combustion stability limit of the exhaust gas burner varied with the utilization ratio of the stack, with increasing of fuel utilization ratio, the equivalence ratio of lifting and flashback limit was changing, and the adiabatic flame temperature of stable combustion limit had been studied.