AAO Steel A/S

Resource conserving treatment of process water from an alkaline washing line.


In addition to Aage Østergaard A/S, the AAO-Steel A/S group in Horsens also includes Scan Press A/S, E.J Værktøj, Brdr. Madsen Maskinteknik A/S and Erik Hudecek ApS.

The company was established in 1924 and has 500 employees.


AAO Steel A/S


Metalworking company specialising in deep drawing, pressing and cold forming.


AAO-Steel A/S disposes of 1,200 m3 of process water each year from an alkaline automatic washing line. Until 2009, the company had annual costs of DKK 720,000 to an external company for the disposal of the process water. In addition, there are costs for
soft water.


Envotherm’s new ET350 now concentrates process water so that only 5% needs to be disposed of. The remaining 95% distilled water is of such high quality that it can be directly recycled back into the process. Oil content <10ppm.
Conductivity < 40μS/cm. The investment was repaid in less than 2 years.