HOW TO REDUCE WATER PURGE (AND ASSOCIATED PROBLEMS) IN LIQUID PRODUCT TRANSFER LINES

If you work in the liquid process or hygienic industries and transfer liquids through pipes, here’s a problem that clients contact us about fairly regularly, and most importantly, how to solve it. ?

What happens is that after transferring a batch of product through their lines, they then purge their process lines with water.

The aim of the water purge is to remove as much of the remaining product as possible.

There are a few issues with this method though.

(If you’re short of time here’s a video summarising this article):

The issues with water purging are not confined to any one type of product.

I’ve seen the same issue in the manufacture of foodstuffs (in particular bakery goods and meat slurries in pet food), as well as some types of confectionery, personal care, chemicals and other products.

The main problems are that water purging is labour-intensive, requires operator intervention, and uses a considerable amount of water.

High water usage is a major problem for companies that are trying to be more environmentally sustainable, and especially if they’re located in water-sensitive locations.

Water flushing or purging is also time-consuming. This is an efficiency drain on any company.

What’s more, if the water is heated for a hot flush, it uses a fair bit of energy to heat the water.

And the longer the flush, the more energy it uses, as well of course water.

Significantly, unless the residual product in the line is retrieved before the flush, then using a water purge wastes the product in the line. Literally sends it to drain.

This product could be recovered rather than sent to flush waste, which is a far more efficient, profitable and environmentally friendly option. ?

Unless the flush water can be recycled or reused, it also creates effluent.

And this unnecessary effluent has costs attached – it has to be treated, stored or transported away.

There are also a couple of lesser-known problems with water flushing that we come across from time to time.

Sometimes, there’s a tendency for the operators to ‘over-flush’. They do this to be on the safe side, in other words, to make absolutely sure there is no product remaining in the line. ?

However, it’s a costly thing to do.

Over-flushing uses even more water (and energy if it’s heated) and takes even longer than necessary, which means more downtime and inefficient use of labour. ?

On the other hand, sometimes the opposite can happen - the flush doesn’t take place at all.

Flushing is usually a manual process and it’s one that can occasionally be overlooked.

Not flushing at all is dangerous. It can result in product quality, contamination and cross-contamination issues.

Sometimes, especially if the products have a tendency to thicken or set, and the flush process isn’t adhered to, it can even result in process lines becoming blocked or clogged with product.

This then requires the removal of some or all the process pipework to find and clear the blockage.

Dismantling the lines is even more time-consuming, disruptive and inconvenient to say the least.?

So here’s how to significantly reduce, even eliminate water flush - use liquid product recovery (pigging) technology.

?Remove the Product Before Flushing by ‘Pigging’

?If you’ve not heard of liquid product recovery technology (otherwise known as ‘pigging’ technology) – here’s an overview of what is pigging.

?By pigging the line before flushing (or CiP), it reduces the required flush time considerably, so saves operator time and labour, along with significant amounts of water and often energy.

There’s also less effluent and associated treatment, transfer and disposal costs.

Sometimes pigging can even replace the flush altogether.

And of course, because the whole pigging process is automated, it reduces the chances of either no flushing or over-flushing.

Importantly the product that would have been flushed away is recovered for use.

Depending on the pipeline specifications and product value, the ROI from recovering the product alone, rather than flushing it to drain or waste, is nearly always a major contribution to the bottom line.

Typical paybacks from @HPS Advanced Liquid Product Recovery (pigging) Technology are usually just a few months. After that, it’s a high ROI year on year – there’s a pigging system savings calculator on the HPS website at https://www.hps-pigging.com/resources/savings-calculator/

If you’re interested in assessing if HPS Product Recovery Solutions technology will work for you, please message me here on LinkedIn or put something in the comments and I’ll be in touch.

?#pigging #manufacturing #liquids #transfer #waterflush #engineering #fluids

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