Reuse of salt waste in 3D printing : case study

Salt waste from desalination plants and potash mining industry al- ready presents an environmental problem. Salt (NaCl) in combination with other materials shows promising mechanical and physical prop- erties and has already been used as a building material in the past. This experimental study focuses on using salt in 3D printing technolo- gy to improve the resource efficiency of both the building material and construction process (speed, cost, accessibility). To analyze the printability of salt mortars, four different material groups (SS- salt and starch, SC – salt and clay, CS – salt and concrete, SG – salt and gypsum) each prepared in six different mixes were eval- uated according to a range requirements (pumpability, printed shape maintenance before it hardens, proper binding time around 30 min- utes, possibility to build another layer and surfaces). The most promising printing mortar was selected for a 3D printing pro- cess with a clay printer (Potter Bot Micro 10) for more complex print objects. The SC printing mortar performed the best in terms of printability requirements, stayed stable after the hardening period and also pre- served the complex printing shape. However, SC print objects showed high efflorescence on the surface and connection problems between printing layers on some positions. In the future special attention should be given to the further develop- ment of the printing mortars. In general, experimental results demon- strate that salt printing mortars provide a promising method for 3D printing.     «

Salt waste from desalination plants and potash mining industry al- ready presents an environmental problem. Salt (NaCl) in combination with other materials shows promising mechanical and physical prop- erties and has already been used as a building material in the past. This experimental study focuses on using salt in 3D printing technolo- gy to improve the resource efficiency of both the building material and construction process (speed, cost, accessibility). To analyze the printability...     »