Generally speaking, ceramic roller roller kiln adopts centralized or semi centralized smoke exhaust at kiln head. The typical centralized smoke exhaust is that two pairs of smoke vents are set on the upper and lower side walls of the roller table at the kiln head. This centralized smoke exhaust method allows the smoke to be fully used to heat the products. However, if this centralized smoke exhaust method is not used in conjunction with other adjustment methods of the pre heating zone (such as fire wall, brake plate, temperature regulating air duct, etc.), it is very easy to cause the temperature of the kiln head to be too high (above 340 ℃ or higher), and the kiln body is required to be fully dried, Or it is difficult to adjust the temperature curve of the pre heating zone, so many ceramic roller kiln and centralized smoke exhaust are used together with several temperature regulating air ducts (similar to the mixing air curtain set up in the pre heating zone, but the main function is not to mix, there is no special requirement for the jet speed of air flow, generally the air ducts are relatively thick, there are hot air using the waste heat of the cooling belt, and there are also direct uses of ambient air).
The semi centralized smoke exhaust method is to set up multiple pairs of smoke vents (generally four pairs) on the upper and lower side walls of the roller tracks of the ceramic roller kiln body in front of the ceramic roller kiln head, or set up several additional smoke vents on the top of the kiln in the preheating zone.
Generally speaking, this semi centralized smoke exhaust method has a relatively low heat utilization rate of flue gas, and has little effect on the regulation of the pre heating zone. Generally, it still needs to be used in conjunction with other regulation methods of the pre heating zone, such as the ram, fire wall and temperature regulating air duct. Therefore, how to set the ram, fire wall or temperature regulating air duct is an important topic in the design and research of the pre heating zone.
At present, the ceramic roller kiln in use usually starts with a fire wall near the first pair of burners, and then sets 1-2 more fire walls in the whole preheating zone. Generally, the middle of the preheating zone is equipped with an array of temperature regulating air ducts. These temperature regulating air ducts are equipped with adjustable valves. Generally speaking, these shutters, fire walls and temperature regulating air ducts can not only enhance the heat exchange between flue gas and products in the preheating zone, It can also increase the adjustability of the temperature curve of the pre tropical zone, and of course, increase the burden of smoke exhaust.
