Structure and working principle of glass kiln regenerator

The regenerator is a waste heat recovery device that performs heat exchange through heat release and heat storage of gas. The temperature of the flue gas (exhaust gas) discharged from the glass furnace is very high, usually about 1400-1500°C. There is still a large amount of heat energy in the exhaust gas, which must be utilized. The purpose of the glass kiln equipped with a regenerator is to save energy on the one hand, and to make the flame reach a higher temperature on the other hand. In the glass kiln, the flame temperature needs to reach about 1700°C, except for the heat provided by fuel combustion. , It is also necessary to use the high temperature of the exhaust gas to preheat the air and gas to ensure that the flame reaches high temperature.

The regenerator of the glass kiln can be divided into vertical and horizontal according to the airflow direction, and can be divided into two kinds of connected type and divided type according to the structure. The structure of the vertical regenerator is shown in Figure 1. The top of the gas flue is built with a regenerator grate, and the grate is stacked with checkered bricks. The wind and fire partition is the partition wall between gas and air. The temperature is high, the flying material is corroded, and it is easy to see through after burning. Therefore, its thickness is large and the masonry is required to be compact. The heat storage outdoor wall is lined with thermal insulation bricks to reduce heat loss. Regenerators often need to repair checker bricks and clean up powder ash, so generally the exterior walls are equipped with hot repair doors and cleaning holes, and ash pits are built in the flue.
When the high-temperature exhaust gas in the glass furnace passes through the regenerator from top to bottom, the lattice body in the regenerator is heated, and the temperature of the lattice body gradually rises, and the lattice volume stores a certain amount of heat; after changing the direction, when the combustion air When the gas passes through the flue at the bottom of the regenerator and enters the regenerator from bottom to top, its inner grid uses the accumulated heat to heat the air and gas, so that the temperature of the gas rises and achieves the purpose of preheating. The regenerator works periodically. One cycle is a heating period and the other is a cooling period. Therefore, its function is to use checker bricks as a heat storage body to accumulate heat in the exhaust gas, and then use this heat to combine air and gas. Warm up. Generally, the air can be preheated to 1000～1200℃; the gas can be preheated to 800～1000℃; the temperature of the exhaust gas out of the regenerator is about 600℃.

In the heat transfer process, the exhaust gas mainly transfers heat to the surface of the lattice body through radiation, and then transfers the heat to the interior through heat conduction; while heating air, the lattice body mainly transfers heat to the air through convection and radiation, because of the O2 and N2 are symmetrical diatoms, which do not radiate or absorb, so the temperature is still dominated by convection heat transfer; when the gas is heated, the radiation effect is strengthened. The reversing time has a great influence on the heat exchange efficiency of the regenerator. In addition, the specific heat capacity, density, arrangement of checker bricks, and gas flow in the channels also affect the heat exchange process. The air flow in the regenerator is mainly the uniform distribution of the air flow on the cross section, which is of great significance to improve heat transfer and heat efficiency.