Inside the oil separator, the flow of the emulsion is very slow so that the oil droplets have enough time in order to float to the surface of the emulsion. Because of using coalescing media, the uplift of the fine oil droplets is accelerated. The emulsion contaminated with small oil droplets flows through the coalescing media. The small oil droplets stick to the surface of the coalescing media. The small oil droplets do not have enough uplift so that they do not float to the surface. The flow resistance in the emulsion is bigger than the small uplift of the small oil droplet.
Because of the high viscosity of the oil droplets compared to the emulsion, the small oil droplets will stick much better to the surface of the coalescing media in the emulsion. The emulsion flows through the coalescing media, while the oil droplets stick to the surface of the coalescing media. Many small oil droplets on the coalescing medial form bigger oil drops. The bigger oil drops have more uplift, and they are separated on the surface of the emulsion. After passing the coalescing media, the emulsion flows back by gravity into the central emulsion tank.
The separated oil floats on the surface of the emulsion in the separation chamber. In many conventional oil separators, the floating oil should flow over a baffle into a waste oil tank. The height of the baffle has to be adjusted to the height of the liquid level in the separator. If the height of the baffle is too low, many oil will flow into the waste oil tank. The result is high consumption of emulsion and high cost for disposal. If the baffle is adjusted too high, a very thick oil layer floats on the surface. The emulsion underneath has no contact to the oxygen in the air, and anaerobic bacteria will grow very fast.
For this reason, the oil separator Skimmtelligent is equipped with Friess oil skimmer model 1U in order to remove the floating oil. The floating oil sticks to the outside of the oil collector tube of the oil skimmer. The oily oil collector tube is drawn into the oil skimmer. The collected oil is removed with scrapers from the surface of the oil collector tube. The oil flows from the scrapers into a waste oil collecting tank. The oil collector tube returns to the surface of the emulsion and picks up new oil. The operating time and the idle time can be set individually for each application so that the capacity of the oil skimmer fits exactly to the oil volume that is separated. The contamination of the waste oil with emulsion is very low, and the disposal costs are low as well.