No. 2 How long will it take to clean my tank?
Watch the video here How long will it take to clean my tank? or read on below to find out how long different types of cleaning in place (CIP) system will take.
So how long does it take to clean a processing or storage vessel? It is a key question and can be one of the most important in terms of operational efficiency. When they're being cleaned, any tanks are not being used for whatever they're normally being used for. So effectively what we have is operational downtime when the tanks are being cleaned. So the time it takes to clean a tank can actually be the most important thing for many customers, and improving on tank cleaning times is a key issue SNP gets asked to address.
So, in absolute terms, it's impossible to actually answer the question because each residue and each tank are different. So rather than talking about absolute terms i.e. for this residue, it will take this long to clean this tank, we talk about it in relative terms, i.e. comparing the different time periods different styles of tank cleaners will take. The length of time any tank cleaning or any cleaning operation needs to run depends on four main things:
- Time is one of the four key factors in any cleaning operation, along with 2. mechanical action, 3. chemical action and 4. heat. Each of these factors combine to give an overall cleaning effectiveness. So if we want to reduce one, we need to increase one of the others and vice versa.
When answering the question, how long will it take to clean the tank we actually need to know what the other three factors are. So it's not a simple question. But, we can look at the mechanical action component because this is the key difference between the different styles of tank cleaners.
We'll assume for the purpose of this exercise that we will keep the chemical action the same and the heat the same. And we'll just look at the varying mechanical action components of the different styles of tank cleaners.
Spray balls have a very, very low mechanical action, and so all other things being equal, they will need longer to clean any tank.
If we increase the mechanical action by upgrading the spray balls to spinners, we improve the mechanical action of the cleaning system and so can reduce the time it takes. Now it's hard to say by how much, but a general rule of thumb we would expect to see the same level of cleaning in about 50 to 75% of the time so a 20 minute clean would be reduced to between ten and 15 minutes.
If we decide to upgrade further to a rotary jet cleaners, then the mechanical action is increased even more dramatically and we can see even bigger reductions in time. The same level of cleaning can be delivered in perhaps 25% of the time. So that same 20 minute cleaning for a spray ball will be reduced to perhaps five minutes with a rotary jet cleaner.
However, there's one big caveat with this. The jet cleaner must be able to complete its complete cleaning cycle to ensure that the jets reach all areas of the tank. Otherwise, parts of the tank simply won't be cleaned. So there's a hard limit on the time savings that can be achieved i.e. you can't reduce the cleaning time below that overall cycle time.
So, with very light residues in small tanks that are cleaned well by a single spray ball in five minutes, you're going to actually struggle to improve the cleaning time even with rotary jet cleaners; most cleaning cycles of most jet cleaners are more than five minutes. You can still improve on overall water consumption by making that upgrade, and the jet cleaner may well do the same job with less water over that five minute period, but from a purely time perspective, improvement is unlikely to be achievable with those kind of light residues in small tanks. However, if the spray ball wash was taking, say, 30 minutes, then it's a completely different story and the rotary jet cleaners will likely produce significant time reductions.
So hopefully that gives you some idea of how to answer the question how long will it take to clean a tank? The absolute answer is it's difficult to give because it's very much dependent on the residue in the tank in question, but the relative answers given here can help you make some sensible decisions when choosing the style of tank cleaning that you want for your CIP system.
To read more about tank wash systems and engineering considerations if you are replacing, upgrading or designing a new CIP solution, visit the SNP website here for lots more information and advice.
Or contact SNP on: