The construction of residential buildings from peat slabs has been known in Northern Europe since time immemorial, but today Estonian scientists are proposing to revise the idea using 3D printing concepts. Peat is cheap, available in abundance, but it is not suitable for creating solidified solutions, which has been proven in the course of many experiments. And now the solution to the problem seems to have been found.
For small Estonia, this could have revolutionary consequences. Peatlands occupy about 22% of the country's territory; this is a colossal source of raw materials. At the same time, the region has developed oil shale mining, about 7 million tons per year, but there is no waste recycling mechanism. The main by-product, ash, is just garbage, and it is dangerous for the environment. But at the suggestion of scientists from the University of Tartu, ash and peat can become revolutionary materials for housing construction.
It is precisely the high pH of shale ash that compensates for the chemical properties of peat that previously interfered with the hardening of binders in the 3D printing mix. It also contains cement and silica nanoparticles, resulting in a concrete-like material. It takes more than a day to completely solidify, so the printing technology of buildings will have to be adapted to new conditions. However, from the very first minutes, the mixture grasps and if you form blocks from it, and not layers, they will retain sufficient elasticity to fuse under their own weight into a single structure without cracks.
The authors of the development indicate that their material is strong, lightweight, durable, non-flammable, despite the presence of peat in the base. It blocks the transfer of heat and sound, but most importantly, it is very cheap, because it is mostly made of garbage. That promises the prospects for cheaper construction and parallel cleaning of the environment in the future.