Amazon Filters Blog

Seawater tests prove value of KilBac filters in combating biofouling

Written by Julie Hoad | April 27, 2021

Offshore oil and gas companies are set to benefit from two new filtration products after the pair passed rigorous seawater trials with flying colours.

Working with a global energy producer, we held a series of successful tests of our recently launched SupaSpun KilBac® and SupaGard Kilbac® filters.

It was the first time the technology behind KilBac’s meltblown fibre construction had been rigorously examined in real-world rather than laboratory conditions.

And it comes as the UK government announced plans to permit more oil and gas wells to be drilled in the North Sea.

The aim of the tests, carried out in partnership with a US-based crude oil and natural gas producer, was to check how well KilBac protects seawater membranes.

Launched just before the pandemic brought much industry production to a halt and reduced the scope for tests on rigs, platforms or FPSOs, KilBac features high-performance antimicrobial and antialgal additives.

The underlying technology harnesses micron-sized particles containing active silver, zinc and copper which, combined with a base polymer, combat the growth of bacteria or algae on the filter, so extending cartridge life and optimising performance.

Amazon Filters Managing Director Neil Pizzey said: “Biological fouling and growth, including algae, can significantly reduce fluid throughput and increase downtime and cost.

“By suppressing the growth of captured organic material, KilBac enables customers to avoid costly premature membrane replacement.

“We already knew it was successful in lab tests but now we have been able to measure its performance in real offshore conditions.”

While both inhibit the growth of bacteria and algae, SupaSpun Kilbac is an absolute depth filter while SupaGard Kilbac is a nominal depth filter.

The difference is that a nominal filter has broader manufacturing tolerances, so enabling greater variations in effective porosity.

Due to the often rapidly changing conditions of inlet seawater it is difficult to obtain definitive comparison testing when running different filters back-to-back as run times vary even with identical sets of cartridges.

To address this issue, the test programme involved challenging three different specification filters with the same quality sea water and biological exposure.

They were the 5-micron anti-algal SupaSpun KilBac, the 5-micron antibacterial SupaSpun KilBac and the 5-micron untreated standard SupaSpun II filter.

Parallel test housings were installed downstream of multi-media beds at the offshore facility, delivering prefiltered sea water at the sulphate reduction stage.

The main criteria for success were demonstrating decreased blocking, robust membrane protection and the potential for increased service life.

The results showed the KilBac filters exhibited half the differential pressure of the standard filters.

The antialgal KilBac also had 39% higher dirt holding capacity than standard SupaSpun while for the antibacterial KilBac, the difference was even higher - a 125% increase in dirt holding.

Neil said: “If biofouling is allowed to occur on prefilters this can break through and foul the membranes resulting in downtime and the expense of cleaning and regenerating.

“Our test results provide compelling evidence that the use of KilBac variant filters in seawater filtration systems can reduce the requirement for changeouts, more than double the service life of cartridges at the prefiltration stage and keep processes operational at times of increased challenge of organic materials due to localised algae blooms.

“The combination of reduced downtime, the avoidance of costly clean-in-place cycles and the reassurance of more effective throughput means oil and gas producers can expect to see substantial cost savings on their filter spend thanks to KilBac technology.”

Read more about seawater testing