Where does the water go that is dried out by these dryers?
Tumble dryers are vented to the outside. Radiators just send the water vapour into the atmosphere of the house, to condense on cold surfaces, I would think that these driers do exactly the same, but faster. Better than sleeping with wet clothes draped around a radiator for days, yes, but the same amount of water has to go somewhere.
Maybe a separate spin-dryer would take out more water than a washing machine - they have better spin speeds - and then whatever method of finishing the drying is used, it will be faster and create less condensation.
If the students can't afford a washing machine or a vented tumble-dryer, then they will be wringing things out by hand - a spin-dryer would be cheaper and more useful than a washing machine to them.