Oil skimmer as a belt skimmer
Belt skimmers are probably the most widely used type of oil skimmer in industrial applications. The belt skimmer consists of a motor with a drive roller and a mount. The drive roller drives a flat, endless skimmer belt. The belt is weighted down by a loose deflection roller and pulled downwards. The lower part of the belt is immersed in the floating oil phase. The oil adheres to the belt and is moved through the water phase below, with the belt. The oil still adhering to the belt is then conveyed upwards and removed from the belt by the scrapers and fed into a collection container.
With this type of skimmer, the removal of tramp oils depends heavily on the belt width. The removal capacity of tramp oils can be up to 8 liters per hour with a belt width of 80 mm, whereas with a belt width of 30 mm the conveying capacity is only 3 liters. These values are realistic maximum estimates that depend on other factors, such as the belt speed, which in turn depends on the performance of the motor. In general, the belt skimmer type is ideally suited for cleaning and maintaining all cooling lubricants, but only for small containers, regardless of the design of the belt skimmer. Belt oil skimmers are easy to install and are often equipped with a magnetic base as standard.
Areas of application
Belt skimmers are often used on machine tools to remove tramp oil from the cooling lubricant. They are particularly suitable for small coolant systems. By removing tramp oil from the surface of the cooling lubricant, the formation of bacteria in the coolant is prevented and the cooling lubricant maintains operating parameters such as oil concentration and pH value for longer. This not only extends the service life of the cooling lubricant, but is also a health and safety measure.
Other areas of application include washing applications such as degreasing baths, parts washing systems or pre-treatment of painting systems. Oil removal is important in these applications to ensure that the cleaning performance of the washing liquid does not deteriorate too much over time. This is because the more saturated the washing liquid is with oil, the less oil it will remove.
Usage of the belt skimmer
This design of oil skimmer is primarily intended for tanks with a smaller surface area. The belt dips into the liquids to be separated vertically to diagonally. Due to the design and function of the belt skimmer, only a small part of the surface is treated. In larger tanks, this would mean that only a small part of the oil floating on the surface is captured, which would reduce the effectiveness. Therefore, the belt skimmer is unsuitable for larger tanks or basins. The tube skimmer is the first choice for larger systems. Here, the tube length can be adapted to the tank size so that there are no dead zones, as the lfoating liquids can be collected over the entire surface.
Prices
Like the similar O-Ring skimmers, belt skimmers are available for well under 1000 Euros. In smaller tanks, they effectively remove oils and thus keep coolants and other liquids clean. This leads to a significantly longer service life and therefore reduces operating costs in the long term. Depending on the intensity of use, the skimmer belt may need to be replaced from time to time, as the skimming of the oil will cause wear and tear after a certain period of time. The prices for a replacement belt vary depending on the manufacturer and should be enquired about in advance. When comparing prices, factors such as warranty period, costs for spare parts, capacity and performance should be taken into account.
Depending on the aggressiveness of the liquid, caused by temperature and pH value, the service life of a skimmer belt can vary greatly. It makes sense to find out whether the manufacturer has different belts that are intended for different operating conditions in order to keep the replacement frequency low.
Design
Belt skimmers are characterized by their very compact design, which means that they can be easily accommodated in tanks that are already very compact. With their small footprint, they also fit through very small openings in tanks, which reduces heat loss in warm applications. Some belt skimmers also have guided deflection rollers, which allows them to be inserted into the side of a tank if installation from above is not possible.
Advantages:
- Small and compact device
- Inexpensive
- Fluid level can fluctuate (with large models also large fluctuations)
Disadvantages:
- Low removal rate
- Does not create a flow on the surface
- Only reaches a small area of the surface
- Scrapers are destroyed by particles
- Sludge can block the drain
Summary
Belt skimmers are your go-to solution, especially for small applications. Thanks to their fabulous price-performance ratio, they are particularly popular for small machine tools and other small applications and work very effectively.
You just have to make sure that the application is not too large. Otherwise, the belt skimmer may no longer be able to remove all the oil present.
More about the other types of oil skimmers:
You can find more detailed information on oil skimmers here!