Investigation on gypsum plaster waste recycling: an eco-friendly material

Reducing the anthropogenic impacts on the environment is an important task, one that must be tackled in the building sector, which has considerable responsibility for such impacts. The amount of construction and demolition waste is increasing, and, consequently, so is gypsum plaster waste. This waste is due to the increase of using gypsum plaster in buildings as renderings and plates. This paper presents results that can enhance the value of gypsum waste recycling, thus reducing the damage the building sector does to the environment. Both the energy consumed in recycling and the way to recycle in stationary kilns were studied in order to establish the best calcination temperature and the residence time. With this result (calcination time and temperature), the properties of the recycled plaster were evaluated in powder, fresh state and hardened state. The results obtained are better than for commercial gypsum plaster, thus indicating that this a good way to recycle and add value to this waste material.