During many industrial processes there occur unwanted or casual mixture of mineral oil substances with water. Especially mineral oil, petrol and fuel oil belong to these substances. Such polluted water is hard to clean, especially when there are not many differences between the viscosity of the polluting substance and the viscosity of water. “The active liquid separator” was made to separate the surface spots of these substances. It uses the unique principle of mechanic – pneumatic separation.

If the water was polluted and there cropped up fat spots on the surface, it is unwanted to drain the liquid because the layers are mixed and there is a necessity to separate carefully both of these layers. The active separator of unmixtable liquids uses the low viscosity of the polluting substance and the small adhesion to the surface of the machinery. The principle of the construction is an obliquely placed rotation disc which has a double ribbon spiral on the working side. This rolled up spiral has a G-form. There is a hollow cylinder with a perforate wall in the middle of the spiral, which is used as a shaft and at the same time as a hydraulic recipient.

The mineral oil substances have thanks to their surface tension the inclination to make spots on the maximum large area and the minimum thickness. That’s why it must be tried to limit the formation of this layer in a maximum way through its active gathering from the water surface and through its concentration to a minimum space, where its height will raise. In this way there will be created conditions for a successful separation.

The gathering of the layer follow through a spiral, which is placed on the lower side of the disc. The spiral is put obliquely to the surface and during the rotation it closes a part of the surface towards the narrow becoming space, which gets on to the middle, where it goes on to the hollow shaft. During the rotation there is caught a little air which forms a bubble. This bubble goes on together with the closed liquid into the hollow space of the shaft and through its pressure impulse and through the pressure powers of water it separates the liquid layer through holes in the hollow shaft into the gathering space (see movie).