Dear frieds
I would like to post again the following . Any help will be appreciate
In a cold room working at -25ºC, one evaporators drains clogged. The evaporator tray overflow and plenty of water felt on the floor forming a mountain of about 20 cm high and 80 cm in diameter . It do not allow circulation of the forklift or elevators to repair the drainage Electric resistance.(heater)

The client do not want to use salt (NaCl) to thaw the ice for corrosion problems on metal shelves.
What other ways could be used to melt or thaw the ice block ?
It has to be food grade and suitable for workers perform i in a closed and cold environment.

The costumer do not want use a chisel and hammer to do the job becouse the workers could damage the floor.
Thanks
Gwapa