The Atotonilco Plant for Treatment of Residual Waters is an industrial facility currently being constructed to improve the water quality for irrigation primarily in the Valley of Mexico. Located in Atotonilco de Tula, in the State of Hidalgo, the Atotonilco Plant will become the largest hydro complex in Latin America, and one of the largest worldwide upon completion.
There are 30 digester tanks in the plant that have already been constructed. These tanks will store blackwater, or sewage, that will be chemically treated and later be used as irrigation for farmers to grow their crops. These tanks operate at a certain temperature, which needs to be maintained at all times, so good insulation is required.