Regular cleaning of large industrial tanks is one of those maintenance tasks that can easily fall by the wayside when more urgent work demands attention. When a tank appears to be functioning normally, cleaning can seem unnecessary. In reality, neglected tank cleaning causes problems that grow slowly but surely. In this article, we cover the most common questions that industrial maintenance professionals ask about tank cleaning and how to time it correctly.
Why is regular tank cleaning important?
Regular tank cleaning is important because sediment, solids, and residues that accumulate on the interior surfaces of a tank degrade product quality, accelerate corrosion, and can compromise the entire production process. A tank that is never cleaned does not simply become dirty over time — its structure also deteriorates more rapidly. Regular tank cleaning is preventive maintenance at its best.
The substances stored in industrial tanks always leave behind some residue. Oils, chemicals, process water, and other liquids build up on the bottom and walls of the tank. These deposits can react with each other or with a new batch of material, leading to contamination. In the worst case, this means an entire product batch is rejected, resulting in direct financial losses.
From a corrosion standpoint, the situation is equally clear. Accumulated deposits trigger chemical reactions against the tank surface, significantly accelerating structural degradation. The longer cleaning is postponed, the deeper the corrosion penetrates. Ultimately, this can lead to costly repairs or premature tank replacement. Regular tank cleaning is therefore also the economically sensible choice.
What risks does neglected tank cleaning pose to production?
Neglected tank cleaning poses three key risks to production: deterioration of product quality through contamination, structural damage to the tank from corrosion and sediment buildup, and the risk of an unplanned shutdown when damage is discovered too late. These risks compound over time, and their costs far exceed the price of regular cleaning.
From a production perspective, the worst-case scenario is an unplanned shutdown. When a tank fails or a contaminated batch is only detected at a later stage in the process, production grinds to an uncontrolled halt. This is many times more costly than a planned maintenance shutdown, where cleaning is scheduled in advance and resources are allocated ahead of time.
Neglected tank cleaning also drives up costs in another way. Residues that have been allowed to accumulate over a long period are far more difficult to remove. This makes the cleaning work itself technically more demanding, which directly increases both the cost and the duration of the job.
How often should an industrial tank be cleaned?
The cleaning frequency for a large industrial tank depends on the substance being stored, the tank material, and the operating conditions. The statutory inspection interval for tanks is 10 years. Tanks storing reactive or easily sedimenting substances require more frequent cleaning. In the food, pharmaceutical, and chemical industries, cleaning intervals are considerably shorter.
In practical maintenance planning, cleaning frequency is best determined on a case-by-case basis, taking the following factors into account:
- The properties of the stored substance, such as viscosity, tendency to sediment, and reactivity
- The material the tank is made from
- Operating temperature and pressure
- Product purity requirements set by the production process
- Inspection obligations imposed by regulatory authorities or the customer
A good starting point is to measure the thickness of deposits and assess the condition of the coating every time the tank is cleaned, and to document the findings. This data helps optimize the cleaning interval for that specific tank and avoids the costs associated with both over-frequent and under-frequent cleaning.
What is the difference between manual cleaning and robotic cleaning?
Manual cleaning involves using a pressure washer inside the tank, washing the walls from scaffolding. Robotic cleaning involves using a mechanical cleaning robot that either moves along the tank walls or operates within its own mechanical structure, without the need for scaffolding. The biggest differences lie in safety, speed, and the ability to handle stubborn deposits. Robotic cleaning is best suited to large tanks and tough, hardened coatings.
Manual cleaning means the work is carried out by a person using a pressure washer. Its limitation, however, is that the job requires a person to work inside the tank for extended periods and potentially at height on scaffolding. This increases both the safety risk and the overall project duration due to the time needed to erect and dismantle the scaffolding.
Robotic cleaning eliminates this problem entirely. The cleaning robot operates without scaffolding, moving in close proximity to the tank walls and continuously maintaining the optimal distance between the wash head and the tank surface. This makes cleaning faster and significantly reduces workers’ exposure to hazardous substances and noise. The robot is suitable for all large tanks regardless of the material they are made from, and is particularly effective at removing old, hardened residues and coatings — tasks that are extremely demanding and time-consuming when done manually.
Choosing the right method always depends on the size of the tank, the nature of the stored substance, and the tenacity of the deposits.
If you would like to schedule your tank cleaning, inspection, or coating work to coincide with your next planned production shutdown, get in touch and tell us about your site. We will assess the situation together and recommend the most suitable cleaning method and schedule for your needs.