An apparatus controls the evacuation of volcanic magma to prevent explosions. Magma evacuation is through a single evacuation tube that heats the magma flow within the tube to prevent stickiness of the magma in the tube. The heating may use small combustion chambers to heat steam, which in turn heats and stabilizes the magma flow. Stability is aided by central cooling, where needed, using water jets from nozzles located at the wall of the tube.