Drying Equipment and Service

Drying Equipment and Service

A dryer is not a system on its own. Measuring whether the drying really works, preventing additive vapors from contaminating the line, and renewing ageing dryers are separate subjects.

Drying cannot be managed without measuring

The display of the dryer shows the drying temperature and the dew point; but what really matters is the moisture remaining inside the granulate. Raw material manufacturers give a residual moisture tolerance per material, and the plant's own internal specification is added on top. The ideal place for the measurement is immediately before or above the feed zone of the processing machine. The moisture analyzer is made exactly for this job.

Additives evaporate

The additives in the granulate evaporate or off-gas at the drying temperature. These vapors accumulate in pipes and hoses and in time lead to system failure. Compressed air dryers do not solve this problem; because they do not work in a closed loop, they release the chemical components into the environment uncontrolled. The additive filter is fitted to the return air of the dryer and separates these vapors.

An old dryer can be renewed

A working drying chamber does not have to be scrapped. In most cases the existing chambers are kept and only the ageing central dry air generator is replaced with a modern one. With a dryer retrofit, an energy saving of up to 100 kWh per ton is possible.

We covered the share of drying in the energy consumption of a plant in our article on energy consumption and saving.