The results that can be obtained by regulating the different parameters of a dryer depending on the relative humidity, temperature and pressure of the combustion gases are immediate. Furthermore, in general, each zone of the dryer requires a different “drying atmosphere”, which requires exhaustive control of the expulsion of humidity throughout the burner zone for its maintenance.
It is in the preheating zone that the energy savings can be greatest. The measurement of relative humidity in the exhaust gases is essential to guarantee both the overall performance of the drying process, as well as an adequate level of quality of the pieces by ensuring a correct and progressive elimination of humidity. Reduced humidity levels in this area can cause unnecessary heat extraction, favoring excessive consumption and the appearance of cracks in the pieces.
A good regulation of the positioning of the opening of valves in the chimney (or inverters of the turbines motors, if applicable), can optimize the RH% in ranges from 1% to 2%, which implies considerable fuel savings.
In addition, the temperature control at the exit of the dryer allows to know and standardize the working conditions in each of the floors of the dryer.
The control of the drying atmosphere provides greater stability to the drying process and the adequate removal of moisture from the pieces. By ensuring constant humidity, the pieces do not suffer strong variations in drying due to the existence of gaps in the dryer. In addition to guaranteeing important savings in gas consumption.
This is the key to minimize heat loss. A check with the OPTIMA® RH analyzers will be essential to correct any mismatch. It is estimated that with effective control of relative humidity and temperature in a drying room, in the presence of gaps, the reduction in consumption and therefore CO2 emissions from combustion will be more than 20%.