Optimising your tank cleaning operations

Tank cleaning equipment is designed to yield specific performance under specific conditions. A variety of factors can affect results. Even when tank cleaning equipment appears to be working as expected, there may be room for improvement. Adjustments are often possible to achieve more consistent results, improve efficiency, reduce the length of time tanks are out of service and lower operating costs.

Here are seven optimisation tips to consider as you evaluate the current performance of your tank cleaning equipment.

1. Heated water vs impact

Hot water is costly but may be needed to remove some residues. However, in some cases, hot water may be eliminated by increasing cleaning impact. This can result in a dramatic reduction in energy costs and savings of thousands of dollars annually. Ask your local sales engineers for assistance in determining if increasing impact can eliminate hot water use in your application. This may involve a proof-of-concept test to compare the cleaning performance of high impact vs hot water. We highly recommend evaluating impact by a tank cleaning expert.

2. Operational considerations

Two tanks that are the same size with the same residue may require completely different tank cleaners and cleaning times. For example, a 3.7 m diameter tank used for food storage may be cleaned using a medium-impact tank cleaner with cycle times averaging 10 minutes if any food residue is still wet. The same size tank may require a high-impact tank cleaner and take longer to clean if any liquid has dried in the tank.

3. Look for issues associated with ‘striping’

High-impact tank cleaners that provide 360° cleaning coverage use solid stream sprays. These sprays don’t overlap as they rotate, so there’s a small distance between each path and striping occurs. The greater the distance the nozzles are from the vessel walls, the greater the distance between paths. In some operations, striping can be a contamination risk. Switching to a three- or four-nozzle configuration, rather than the standard two-nozzle configuration, is one way to reduce striping and minimise risk.

4. Shorten cleaning time by increasing impact

Simple adjustments to liquid pressure and flow may enable a reduction in the number of cycles needed for thorough cleaning. Faster cleaning saves time and reduces water and chemical use. To increase impact and cleaning efficiency, it’s far more effective to increase flow than liquid pressure since increasing flow rate intensifies impact at a greater rate than increasing pressure. In fact, doubling flow rate boosts impact as much as 100% while doubling liquid pressure provides only 40% more impact. In addition, there are other drawbacks to increasing pressure. Higher liquid pressures can introduce turbulence to the jet stream, reducing throw and cleaning efficiency.

5. Cleaning hard-to-reach areas

Internal obstructions, like agitator shafts/blades, coils, etc, block the spray from hitting the tank wall. Certain areas, such as skim lines, require more cleaning than others. Having the flexibility to reposition tank cleaning equipment can help you achieve complete cleaning in less time and reduce operating costs. An adjustable ball fitting can be used to clean vessels in sections: clean the top half of the vessel, then lower the device and clean the bottom half of the vessel or change the angle to clean difficult locations. Lances and adjustable flanges can also be used to help position nozzles properly. For example: if the tank only has a single-entry opening, special lances and flanges can be used so the nozzle turret can be easily moved to multiple locations in the tank. Special lances and flanges can also be used to position nozzles so the spray impacts directly on heavily soiled areas or skim lines.

6. Review system components

In addition to the tank cleaner, other equipment can affect cleaning performance. Pumps: check that you have the correct pump for your system. The efficiency of the pump will have a direct impact on flow and the performance of the tank cleaning equipment. Piping and valves: be sure pipes and valves are properly sized. Incorrect sizing can lead to inadequate flow, pressure and fluid velocity. Filtration: confirm that required filtration products are installed. Filters or strainers should be properly sized and installed to prevent clogging. Monitoring: ensure gauges or flow meters are placed in critical locations. System monitoring will enable quick detection and resolution of problems.

7. Perform regular maintenance

After installing the tank cleaner, documenting the performance will help establish a baseline for later comparison. Also, be sure to inspect equipment on a regular basis. Verifying operation can be challenging since it is difficult to visually observe tank cleaning equipment while operating. Problems with tank cleaning equipment often become evident when trace amounts of residue are detected after cleaning. Watch for debris build-up. Debris can clog nozzles, become embedded in bushings and gears and cause the unit to stop working or reduce service life. Even if you are just cleaning with water, rust or scale from piping may accumulate in the unit. Make sure to put your tank cleaners on a routine maintenance program to check bushings, seals, bearings and nozzles and make sure they are not worn or clogged. Be sure to document when service is done and how frequently components are replaced.

Spraying Systems Co. Australia are tank cleaning experts that can provide help to optimise tank cleaning operations. Local sales engineers are available to evaluate a site's current operations and equipment, and offer optimisation suggestions to achieve specific tank-cleaning objectives.

For more information: https://bit.ly/3cMupuW.