A plant may have five oily pits without needing five oil skimmers. The more useful question is how many locations actually need to be skimmed at the same time.
Do you really need an oil skimmer at every pit?
Industrial sites often accumulate free-floating oil in several different places: wastewater sumps, process tanks, scale pits, wash-water collection areas, retention basins or outdoor ponds.
The obvious solution is to install a permanent oil skimmer at every location. In some plants that is exactly the right answer. But if the oil load is intermittent and the locations can be treated one after another, a mobile oil skimming system can allow one recovery unit to serve several points around the facility.
That changes the buying decision. Instead of asking “How many pits do we have?”, start by asking “How many pits need oil removal simultaneously?”
Buy one skimmer per location — or share one system?
There is no universal answer. A mobile system can reduce the amount of equipment required only when the operating pattern allows the same system to be moved between locations.
The economic opportunity comes from sharing unused capacity. If Pit A only needs skimming on Monday, Pit B on Wednesday and Pit C after a weekly washdown, three permanent systems may spend most of their time standing idle.
If all three pits continuously receive oil at the same time, moving one skimmer between them can create untreated periods. In that situation, dedicated fixed systems may be the more appropriate design.
Start with simultaneous demand
The number of tanks or pits alone does not determine the number of skimmers required.
Periodic oil accumulation
- Several locations require skimming at different times
- Oil accumulates slowly between treatment cycles
- Operators can move the system safely between locations
- The same collector-tube configuration is suitable for the oils involved
- Temporary treatment does not disrupt the process
- Access for cleaning or maintenance requires the skimmer to be removable
Continuous simultaneous duty
- Several locations generate significant oil continuously
- Leaving a pit untreated creates process or discharge risk
- The skimmer cannot practically be moved between locations
- Different oils require substantially different configurations
- Automated unattended recovery is required at every location
- Moving equipment would create excessive labour or operational disruption
Do not compare purchase price alone
The relevant comparison is the complete operating solution: equipment, installation, labour, mobility and the required availability of oil-removal capacity.
Size the number of skimming systems around the maximum simultaneous oil-removal requirement, then evaluate whether the remaining locations can share mobile equipment.
This is more useful than automatically specifying one skimmer for every pit, sump or tank on a site plan.
From wheeled cart to complete mobile recovery station
A “mobile oil skimmer” can mean anything from a compact wheeled frame to a complete tank-mounted recovery system. The correct level of mobility depends on the site.
For nearby locations
A wheeled cart allows the skimmer and associated recovery equipment to be rolled between accessible pits, tanks or sumps. This can work well where the treatment points are relatively close together and manual movement is practical.
For larger industrial sites
Pallet-mounted systems can be moved by forklift or pallet jack. This suits larger equipment and plants where operators already use materials-handling equipment to move machinery between process areas.
For pits, ponds and remote locations
The largest configuration combines the oil skimmer with a collection tank, transfer equipment and balanced boom so the complete recovery system can be repositioned around large industrial pits, ponds or lagoons.
Four situations where a shared skimmer deserves consideration
When mobility needs storage and extended reach
At the larger end of the range, mobility is no longer simply a skimmer mounted on wheels.
The Mobile Extended Reach Skimming Station combines the skimming system with a recovered-oil tank, oil transfer pump, controls and balanced boom. This allows the operating portion of the system to reach out over a pit or pond while the main equipment remains on accessible ground.
A mobile skimmer is only economical if it is practical to move
The lowest equipment count does not automatically produce the lowest operating cost. Check these points before deciding to share one system between many locations.
Map every oil-recovery point before choosing equipment
Create a list of every pit, tank, sump or pond where floating oil is a problem. For each location, record:
- how quickly oil accumulates;
- how often it needs to be removed;
- how long the skimmer needs to operate;
- whether other locations need treatment at the same time;
- the oil type and process-liquid temperature;
- access, distance and available power;
- and what happens if treatment is delayed.
That exercise normally makes the architecture much clearer. Some sites will justify several permanent skimmers. Others may have many oil-collection points but only require one or two shared mobile systems.
Make sure the same collector technology suits the intended locations
A shared mobile system becomes particularly attractive when the same collector-tube configuration can work effectively with the oils and process liquids found at several recovery points.
For unfamiliar applications, the Oil Skimmers Tube Test Kit can be used to evaluate collector-tube pickup with the actual oil and process liquid before the final system is specified.
This is especially useful where one mobile unit is intended to serve several different processes and you want to verify the application before committing to the complete system.
Do not buy skimmers based only on the number of pits
If five locations continuously need oil removal, five permanent systems may be justified.
If five locations need treatment sequentially, however, installing five complete systems may provide far more equipment capacity than the plant actually uses.
The better starting point is the maximum simultaneous treatment requirement. Once that is known, fixed and mobile systems can be combined around the way the site actually operates.
Mobile and portable oil skimmers
Can one oil skimmer be used on multiple pits or tanks?
Is a mobile oil skimmer always cheaper than several fixed skimmers?
When should separate fixed skimmers be used instead?
What is the difference between cart-mounted and pallet-mounted systems?
What is a Mobile Extended Reach Skimming Station?
How large can the mobile collection tank be?
Can a mobile skimmer be used at a remote pond?
How do I know whether a mobile system will work with my oil?
What information should I provide before selecting a mobile oil skimmer?
Map the whole site before buying the first system
Filtra International can review all intended recovery points together and determine whether the application is better served by individual fixed skimmers, one mobile oil-skimming system, or a combination of both.