Patent RU-2762677-C1 (RU)
Title: Flotation device with thresholds and hydraulic means for separating oil droplets
Inventor: LARNHOLM PER REIDAR
IPC: C02F1/40
Filed: 2019-08-22
Granted: 2021-12-21
Abstract: FIELD: mechanical engineering.  
     SUBSTANCE: proposed group of inventions relates to a flotation device designed to separate one phase from a dispersion containing at least the first continuous phase and the second dispersed phase. The flotation device, in particular, is suitable for separating oil from a dispersion containing water as a continuous phase and oil as a dispersed phase, with the formation of a fraction of pure water and a fraction enriched with oil. The flotation device comprises a tank in which there is: a dispersion inlet forming the inlet end of the tank, an outlet of the first fraction with a low content of the second dispersed phase forming the outlet end of the tank, an outlet of the second fraction with a high content of the second dispersed phase, a gas outlet, at least one bottom threshold, at least one overflow threshold, at least one gas injection device containing at least one hole for injecting gas or dispersion of gas in liquid into the tank, at least one removal means, intended for the removal from the surface of the liquid of the second fraction formed during the operation of the flotation device on the surface of the liquid, and at least one hydraulic means designed for the hydraulic pushing of the second fraction formed during the operation of the flotation device on the surface of the liquid in the tank, into the means of removal by liquid flow, by gas-liquid flow and/or by gas flow, while the corresponding liquid flow, the gas-liquid flow and/or gas flow is discharged by hydraulic means to the surface of the liquid in the tank and/or to the second fraction formed during the operation of the flotation device on the surface of the liquid. The overflow threshold is located at some distance and is shifted towards the outlet end of the tank from the bottom threshold. At least one opening of at least one gas injection device is located vertically below the bottom threshold or is located in a channel formed between the bottom threshold and the overflow threshold. The vertical distance between the bottom threshold and the overflow threshold is from 30 to 80% of the height of the tank, while the vertical distance between the bottom threshold and the overflow threshold corresponds to the distance between the lower edge of the bottom threshold and the upper edge of the overflow threshold. In the above flotation device, a method for separating oil from water is carried out, in which a dispersion containing at least the first continuous phase and the second dispersed phase is fed into the intake of the dispersion of the tank with a certain flow rate, so that during the implementation of the method, a certain liquid level is maintained in the tank exceeding the upper edge(s) of the overflow threshold(s), gas or gas dispersion in the liquid is fed into at least one gas injection medium, the second fraction enriched with the second dispersed phase, by means of a means of removal, the first fraction with a low content of the second dispersed phase is removed through the release of the first fraction and the gas is removed through the gas outlet.  
     EFFECT: increase in the efficiency of separating one phase from another.  
     15 cl, 3 dwg