Oil skimmers are pieces of equipment that remove oil floating on the surface of a fluid. These generally work because they are made of materials to which oil is more likely to stick than the fluid it is floating on. At the same time, the fluid has very little attraction to the equipment.
Oil skimmers are usually all that is necessary to remove oil from a liquid. In some cases, however, they may be used to pre-treat a fluid. In this case, they remove as much of the oil as possible before more expensive and time-consuming measures are employed. Pre-treating the fluid this way reduces the overall cost of cleaning the liquid.
There are several different types of oil skimmers, though all designs depend on the laws of gravity and on surface tension in order to function. The six primary types are belt, disk, drum or barrel style, mop, large tube or mini tube, and floating suction oil skimmers.
Belt oil skimmers utilize a belt of stainless steel. This belt is lowered into the liquid that needs to be cleaned. The belt then passes through special wiper blades, which remove the oil from both sides of the liquid as it passes through.
Disk oil skimmers use a disk that is rotated through the liquid. The oil is wiped off the liquid and placed into a special collection container within the skimmer. This type is not a good choice for shallow liquids or for places where the liquid level fluctuates, because it is most effective when the entire disk is immersed.
Drum or barrel style oil skimmers are like the disk version, but they use a rotating drum rather than a disk. In addition, they tend to be more durable and are capable of moving more water than disk oil skimmers. Fluctuation liquid levels, however, are still problematic for drum or barrel skimmers.
Mop oil skimmers use a special type of rope to pick up the oil. The rope dips into the liquid, removing the liquid and the oil. The rope is wrung out with pinch rollers as it goes into the drive unit. When used with high viscosity oils, the ropes in these devices tend to become matted down and lose their effectiveness. In addition, replacement mops can be somewhat costly.
Large tube oil skimmers utilize a plastic hose, which runs over the liquid’s surface and draws the oil in. They can only be used for areas with a large surface area. For smaller surface areas, mini tube versions are a better choice. They work in the same manner, but utilizessmaller hoses.
Floating suction oil skimmers come in a variety of shapes, but each type includes a floating intake. These are best to use with thicker layers of oil.
