Combining infrared radiation and air management to reduce energy use
Infradry systems from Heraeus Noblelight GmbH (Hanau, Germany) make printing and coating applications significantly more efficient, as infrared emitters work in conjunction with a specially developed air management system to reduce drying time.
Drying coatings and inks is an energy-intensive process, which is reason enough to put conventional dryers to the test. Infradry modules combine intensive IR radiation with a controlled air supply and exhaust system to ensure effective drying.
This was accomplished with the help of computational fluid dynamics (CFD) to coordinate radiation and air extraction via computer simulation before the system was built. Initial tests with customer materials confirmed the simulation. The drying speed was up to 20 percent faster than with conventional dryers.
The air management system has been designed to absorb and then remove the moisture that is driven out of the coating by the IR emitters. This accelerates drying by preventing the atmosphere inside the process area from becoming oversaturated.
With a power density that is customised to the application and highly polished reflectors that concentrate the infrared radiation on the substrate surface, the new Infradry systems provide very efficient drying. Their modular construction makes them easily scalable for any working width, and they can be configured with a variety of interfaces. Infinitely variable power ensures exact control of drying.
There are currently two types of Infradry systems: The Infradry Compact has a very small footprint, and is easily expandable. The Infradry Combi is suitable for larger facilities and is the first drying system in the world to extract the air between the emitters within the infrared emitter field. Unlike conventional dryers, the moisture is extracted directly from the process area, making infrared drying more thorough, as a result.
High-performance twin-tube IR emitters provide the heat for drying inks and dyes. Depending on the application, shortwave or mediumwave emitters can be selected. Shortwave emitters produce very high temperatures very quickly, while mediumwave emitters are considered the most efficient method to dry inks and coatings gently to protect the paper.
Heraeus Noblelight offers the whole range of infrared radiation—from near infrared (NIR) to mediumwave carbon infrared (CIR), conducts trials with the materials, and provides guidance in selecting the optimal emitter for every process.