Turkey’s First Freeze-Dryer to be used in conservation
Turkey’s first freeze dryer used for waterlogged organic archaeological artifacts was engaged at Istanbul University Yenikapı Shipwrecks Project Research Center Laboratory. This technique developed using the latest technology for conservation of organic artifacts found at underwater excavations is preferred primarily among the contemporary conservation techniques in the world. The first trials of the device were completed successfully.
After satisfactory results of the PEG impregnation, all of the timbers of Çamaltı Burnu 1 Shipwreck which is the first underwater excavation conducted by Turkish scientists, are undergoing the freeze drying process. In the previous days after the successful completion of the process, for the first time after 800 years, timbers from the shipwreck were completely dry and displayable at a museum.
The first step in the process is a preliminary PEG (polyethylene glycol) impregnation.
Therefore, during the lyophilization (freeze drying) it prevents the water inside the wood structure to expand. Later, the timbers are placed inside the freeze-dryer and the water inside the wood is removed by sublimation. The freeze-dryer primarily reaches the freezing degree of PEG and removes the solid water in the wood directly as vapor. In this method there is no surface tension on the wood, therefore shrinkage, crackage or dimensional deformations are not formed on the timbers. After the process, timbers appear natural.