Heat recovery in drying processes
SiccaDania developed its technology to drastically reduce the energy costs of drying processes. Besides saving energy it also reduces CO2 and NOx emissions, counter dust emissions and reduce the ecological footprint. This is done through the use of heat recovery systems and high-efficiency cyclones.
The heat used for evaporation and drying processes often originates from fossil fuels. These are not only scarce, but are also becoming more and more expensive. This forces companies to make drastic energy savings. SiccaDania, specialist in spray drying, evaporation and filtration, offers specific, directly applicable solutions for these energy-intensive processes. The portfolio includes systems for heat recovery, optimized process automation and high efficiency multi-cyclones.
Fig. 1 Simple representation of a heat recovery system.
Reduction of product loss
The easiest way to save energy is to limit product loss by efficient dust emission reduction. Sicca-Dania uses the ‘powder in the bag’ principle for designing its systems. Often the combination of SiccaDania VTK cyclones and multicyclones are sufficient enough to fulfill the most stringent regulations. The energy-efficient VTK cyclones can replace bag filters, so that captured powders are not lost but can be reused as an end product.
SiccaDania’s CIP-cleanable heat recovery system includes a pillow plate heat exchanger whose air side can be cleaned during the production. This means that dust particles that may have been released during the drying process can be easily removed. The liquid on the fluid side of the system transports the absorbed energy to the location in the drying process where the energy is needed.
The application of heat pumps in dryers is not new, but it is very actual. The integration of a heat pump in a dryer heat recovery system can result in substantial additional energy saving. Savings of 30 and sometimes as much as 50 percent can be achieved. The payback periods vary from 2 to 6 years, depending on the process conditions.
Besides reducing the energy the reduction of CO2 and NOx emissions not only lowers the ecological footprint, but is also financially attractive. Since January 2021, a national CO2 tax is in place to encourage companies to contribute to the climate goals. In addition, a reduction can make it possible to realize projects without exceeding the permissible emissions.
SiccaDania’s OptiPC automation system stands for Optimal Process Conditions (OptiPC). The software determines the optimal process conditions for a drying process based on a range of parameters, such as air humidity, temperatures, volume flows and product supply. With this simple ‘add on’, energy savings of 5 to 15 per cent can be achieved, without major investments in dryer modifications.
Fig. 2 An easy to clean pillow plate heat exchanger.