The process is similar to that of freeze-drying. First, the body is frozen to minus 18 degrees Celsius and submerged in liquid nitrogen. Under such low temperatures, soft and elastic materials become hard and brittle. The body is then refrozen to minus 196 degrees Celsius, causing crystallization. After two hours, the liquid nitrogen evaporates as harmless nitrogen gas. 60 seconds of ultrasonic vibration reduces the remains to powder. The powder is then passed to a vacuum-sealed chamber, where frozen water sublimates and is released as steam. Afterwards, mercury, sodium, and more than 50 other foreign substances are removed. The remains are packed into an organic coffin and buried. After a year, the remains turn into soil, which can feed a tree. Irish company Eco Legacy offers a similar burial service, with the exception that the expelled energy is reused in future burial processes.