How well does Cathodic Protection negate corrosion when used in Seawater Filtration?

The problem with cathodic protection of metal

Ballast water filters need to withstand the most challenging circumstances in seawater filtration. Why is Cathodic protection considered the industry standard for corrosion prevention, and is it the most effective solution available?


A recent report made public by the U.S. Maritime Administration stipulates that, as of January 1st, 2015, there were 41,674 ocean freight merchant vessels (weighing in at 1,000 gross tons and over) registered with an International Maritime Organization number and sailing through waterways across the globe. Among the ships in this worldwide fleet are vessels ranging from container and general cargo ships to tanker ships.

While these ships run the gamut with respect to size and functionality, they all share a single and particularly significant vulnerability. They all run the risk of falling prey to corrosion-related degradation of their ballast water filters due to the various corrosion challenges facing ballast filtration systems.

Taking in seawater for ballast naturally invites a host of microorganisms that ballast water filters need to treat, such as Sulphate-reducing bacteria and phytoplankton, which stimulate microbiologically influenced corrosion (MIC). The filters not only need to protect the ballast water tanks from MIC, but they are also subject to rust themselves and need adequate protection against it.

After several challenging years focused on securing regulatory compliance under the Ballast Water Management Convention (BWMC) and U.S. Coast Guard’s Final Rule for ballast water treatment, shipping’s priority has shifted to operational compliance, which ensures BWMS are compliant for the lifecycle of the vessel.

At the Marine Environment Protection Committee (MEPC) 75th session, the International Maritime Organization (IMO) issued guidance to Administrations that all BWMS installations should be tested following commissioning. This requirement, as well as guidance previously issued by individual flag administrations, has provided the first glimpse into the real-world performance of ballast water management systems after installation.

One of the main reasons for BWT failures during compliance testing is organisms over 50 microns, which clog the system. This can be prevented by a strong and robust filter. Without it, the effectiveness of the entire BWTS could be compromised, leaving manufacturers open to criticism from ship owners and operators, who must repeat unsatisfactory tests at a later date.

In an ideal situation, to ensure uninterrupted operation and protect BWTS, the recommended practice of leaving the ballast water filters full at all times or emptying and drying them would help prevent corrosion and its subsequent degradation from taking root. However, the need to take on more ballast water to accommodate the absence of cargo during particular portions of a given voyage and unexpected rough operational conditions during loading and unloading procedures often makes it difficult to successfully and satisfactorily complete the process on a thorough and regular basis. The result: sedimentation accumulates on the ballast water filters, leading to reduced service life, the risk of failures, and high, short- and long-term maintenance costs.

To ensure uninterrupted operation regardless of varying water conditions and other unpredictable factors, ship owners need effective and dependable filtration systems that protect their entire ballast water management systems. The filters remove as much matter from the water as possible before it goes on to secondary treatment, reducing the amount of chemicals needed and time required to neutralize living organisms in the water. If the filters themselves are not adequately protected from corrosion, they might not filter water effectively, incurring frequent maintenance and replacement costs.


Cathodic Protection for Ballast Water Filters in Seawater Applications

Today, most ballast water filter screens in the world are made of 316L stainless steel. Cathodic protection is the most common corrosion protection method for this type of steel, making it widely used in vessels worldwide. Cathodic protection safeguards the metal against corrosion by connecting the at-risk steel to a highly active “sacrificial metal” acting as an anode. The anode introduces free electrons to the space and relinquishes its ions. In doing so, the formerly active 316L steel areas on the screen’s metal surface become passive, and the new, more active metal coating ultimately and safely corrodes instead.

While Cathodic protection is a well-tested methodology and is being successfully used in many seawater applications to negate the effects of corrosion, the time has come to ask if it is the best option for ballast water filters. This is because, though it has long been recommended by filter and screen manufacturers to provide the necessary protection for ballast water screens made of 316L steel, this corrosion protection approach has some significant drawbacks.

A sacrificial anode can be used for protecting the filter’s screen, but the anode is consumable, and its dissolving leads to the formation of a hard scale on the screen surface. This scale is caused by the buildup of calcium carbonate. On a flat or consistent metal surface, this build-up is not as problematic as it is when it forms on complex metal structures such as woven filter screens and results in clogging of the screen pores. This is because the woven screens have a much higher surface area that is exposed and where calcium carbonate can build, but also because the increased surface area also increases the area at risk for common corrosion problems to start. These factors contribute to an environment that produces high amounts of calcium carbonate that can reduce the size of the screen’s pores, reduce the flow rate, or simply block the screen altogether. In high consumption rates of the anode, this becomes a critical risk and requires regular cleaning of the screen.

The economy of Cathodic protection is less-than-ideal. Although it is cheaper than other alternatives, installing Cathodic protection is complicated. Once it is up and running, ongoing electricity supply and periodic inspection and maintenance fees add to the cost.

While Cathodic protection is a viable solution, its durability may call its high investment requirements into question. In particular, the sacrificial anodes’ limited available current and their vulnerability toward rapid corrosion lead to a shockingly limited lifespan.

Furthermore, sacrificial anodes need to be immersed in an electrolyte for a minimum of 24 hours before Cathodic protection can be applied. If filters are not regularly kept full as recommended by manufacturers, the sacrificial anodes need to be immersed for 25% of the voyage.

With such downsides to Cathodic protection, it would only be natural to ask: Are better options available?


Alternatives to Cathodic Protection

One of the best alternatives to Cathodic protection is using a higher-grade stainless steel for ballast water filtration. For example, 904L steel eliminates the need for Cathodic protection altogether. Traditionally used in the high-technology, aerospace, and chemical industries, 904L is also famously utilized in Rolex’s luxury watches. It has been chosen by luxury watch manufacturers thanks to its higher polish and water-corrosion resistance, enabling wearers to go about their daily business wearing the high-ticket accessory worry-free.

Austenitic stainless steel 904L has a higher percentage of nickel and chromium than 316L steel, in addition to copper. Its composition provides it with superior corrosion resistance capabilities, rendering Cathodic protection unnecessary.

Indeed, 316L steel is the traditional staple coating historically relied on by the ballast water market, and as such, it is regularly produced and widely available. But while 904L is less common, it is still relatively available, and can be supplied with excellent lead time.

Though the initial cost of 904L steel is higher than that of 316L steel, due diligence processes have found that the benefits of applying 904L steel for ship ballast filters in seawater applications far outweigh the costs. The higher durability requires less maintenance and extends the lifespan of screens and filters, ultimately saving the industry precious stakeholders’ time and money in the long term.

If better corrosion resistance can be obtained by upgrading the steel, the traditional choice of 316L steel for ballast water screens, which necessitates Cathodic protection, needs to be re-evaluated.


Bottom line

Using Cathodic protection to prevent corrosion of ballast water filter screens made of 316L steel requires more frequent maintenance and part replacements, leading to increasing costs over time. The sacrificial anodes used in Cathodic protection stimulate the formation of scale, which clogs the screens. Installation of Cathodic protection is complicated, and the anodes need to be immersed in an electrolyte for a significant portion of the voyage. Overall, Cathodic protection is complicated to install and is a less durable corrosion prevention approach than other existing solutions available in the market today, such as using a higher grade stainless steel.

Several parameters have been used to evaluate corrosion prevention approaches for ballast water filtration systems, including Pitting Resistance Equivalent Number (PREN), Pitting Resistance Accelerated Test, corrosion rates in acidic conditions, and natural seawater tests. A new comparative analysis of corrosion resistance approaches is now available for download in a special free white paper.


Download it now: Overcoming Corrosion of Stainless Steel Screens in Seawater Applications.

Filtersafe Develops New UV BWMS Filter

Manta Series: Engineered Ballast Water Filtration Dedicated to UV BWMS

Compact, high-performance, and easy-to-maintain MANTA filters, created in response to market feedback, also receive equivalent series type approval.


ISRAEL; 2nd June 2022: Filtersafe, a world leader in automatic seawater filtration, has today announced its new ‘MANTA’ filter series, with the first of the portfolio exhibited at Posidonia 2022 in June.


The company’s latest high-performance filter is able to maintain impressive removal rates – 99.6% of organisms over 50 μm – all in a cost-effective package with a small footprint, specifically engineered for UV-based ballast water management systems (BWMS).


These organism removal rates ensure that ship owners and operators will be compliant with the International Maritime Organization’s D-2 standard for the implementation of the ballast water management convention, which must be adhered to by 08 September 2024, as well as the U.S. Coast Guard’s (USCG) existing ‘Final Rule for Ballast Water Treatment’.


Filtersafe has received an equivalent series type approval from Det Norske Veritas (DNV) and the USCG. As one of the first complete filter redesigns to be approved under the USCG’s Policy Letter (CG-OES 03-20) Guidance on Testing Alternate Components for a Type Approved BWMS, the MANTA reflects one of the first true evolutions in ballast water filtration since the complex and costly testing regimes were mandated. Gaining approval under this policy ensures that customers of the performance-leading BallastSafe filter now have a new, more compact option to add to their BWMS portfolio.

The MANTA filters family

The MANTA features Filtersafe’s new one-motion scanner. This new design removes lateral motion of the scanner, reducing cost and eliminating parts. It features a larger proximity nozzle which is able to clean the filter screen in one continuous motion. When combined with the filter’s unpleated screen, the MANTA has improved cleaning coverage that reaches 100% of the screen.


A high-performing filter with scalable automatic self-cleaning technology is particularly important for BWMS operations in challenging water conditions, which is a priority for regulators and ship operators alike. Automatic filter cleaning can be increased when ballasting in sediment-rich waters, including those found in the port of Shanghai, to ensure a consistent flow rate and to avoid costly operational issues such as clogging. Despite being tested with a finer mesh filter, the MANTA outperformed the original BallastSafe design in independent testing of the cleaning, removal rate, and throughput efficiency of the filters.


Corrosion prevention remains another key industry pain point. Filtersafe introduced 904L stainless steel across its filter screen supply chain last year and this superior steel is also used in the MANTA series’ sintered screens. In addition, and in order to combat the steady-rising cost of alloy material, Filtersafe, together with its partners, has adopted a new SuperQuenching procedure, borrowed from the space industry, to overcome the material degradation of 316L due to the weaving, sintering, and fabrication process. This allows it to also offer a viable 316L screen option at a lower cost. Improved longevity and superior cleaning reduce maintenance costs and, even when maintenance is required, MANTA is thoughtfully designed to ensure it can safely and efficiently be maintained by one person.


Mark Riggio, Head of Marine at Filtersafe, commented: “As requested by leading BWMS manufacturers, we’re pleased to offer Filtersafe performance in a smaller package, designed specifically for UV systems. Having equivalent series type approval already completed makes adopting a MANTA filter a no-brainer for our current customers. The rising challenges posed by sediment-rich water conditions are not going away – and now we have the filter that anyone can use to meet them.”


“From a shipowner and operators’ perspective, MANTA is a win in both the CAPEX and OPEX categories. You expect CAPEX costs may be a little more for a high-quality filter, MANTA disrupts that. And our OPEX costs have always been Filtersafe’s strong point. If you have any questions about this or just want to see a MANTA filter, I encourage you to swing by the Filtersafe booth at Posidonia.”


Ballast water management is one of the toughest water treatment challenges in the world and demands the best technical solutions. There is sufficient technology and innovative equipment available on the market today to overcome operational challenges and ensure seamless, cost-effective regulatory compliance.


Powerful Lessons to Be Learnt From BWMS Operational Data

Ballast water management systems (BWMS) haven’t been the black-box solution that many shipowners had hoped for. They work, but as participants in a webinar hosted by De Nora and Filtersafe heard, there are outside variables that can make them challenging for managers and crew, especially if they don’t have quality equipment and adequate support from manufacturers.

Taking a look at some real-life case studies, the participants in the “What can vessel data tell us about BWMS commissioning & operation?” webinar (see full webinar below) discussed crew training, system commissioning, and striking a balance between power consumption and filter capabilities.

In one case study, crew operating their system for the first time found that while the portside pumping system worked as expected, the starboard system sounded the differential pressure alarm and shut itself down. Initially suspected to be a filter backflushing problem, the true cause lay in the design of the piping. This was only picked up by careful analysis of the system’s data logs by Filtersafe personnel who were then able to propose a workaround to the crew.

Why wasn’t this picked up during system commissioning? Sometimes both port and starboard pumps are not run simultaneously during commissioning – sailing schedules and crew availability can lead to such risks being taken.

In another case study, the crew complained that the filters were backflushing all the time – and the crew suspected that the culprit was the challenging waters in which the vessel was ballasting – but that ultimately wasn’t the cause of the problem. Rather, after manual cleaning, the filter was being reassembled incorrectly causing premature component wear. A further look at the data logs revealed another problem – an undersized airflow line. The problem was subsequently fixed on the vessel and also other vessels in the fleet.

It’s important that crews do not continually resort to bypassing systems. This would endanger the environmental objectives that ballast water treatment systems are designed to prevent: the spread of harmful aquatic organisms. One compliance issue which was highlighted is the proliferation of organisms in the ballast tanks, and therefore the criticality of emptying and cleaning the tanks regularly.

As an equipment manufacturer, De Nora provides intelligence and support to ship managers to monitor operations and avoid any issues that might frustrate crews. Furthermore, De Nora can help optimize power usage and reduce power consumption when ballasting in less-challenging conditions. This can be achieved regardless of treatment technology (UV or electrochemical dosing) and it can be done without risking schedules or compliance with D-2 standards.

Ballast water manufacturers, operators, and regulators have collected a lot of data so far during the experience-building phase of the regulations. It’s important to leverage this data to make sure shipowners – and regulators – can be confident that systems are working as intended when onboard a ship, and to make sure that ballast water rules have the positive environmental impact they were designed for.

The biggest takeaway from this data is that quality pays. Working collaboratively with quality, expert partners, and installing the highest quality systems is the best way to reduce operating costs, save time for both ship operators and crew, and deliver compliance.

Installing a cheap, low-quality system – where suppliers are not acting as technical partners – means buying twice, with almost certain costly failures and no tools to rectify them. And the ramifications of this will only become more extreme as ballast water is more heavily policed in the years to come.

And let’s not forget why ballast water treatment is so important! While significant attention is being given to finding effective solutions to the industry’s decarbonization challenge, the risks of invasive species remain real and dramatic. As we strive for a more sustainable future for shipping, environmental stewardship requires taking responsibility for both water and air alike.

Here is the full webinar with division in chapters for your convenience:

Filtersafe’s Smartweave Screen: Water Filtration at a Whole New Level

The heart of any filtration system is the screen. It is the barrier that keeps downstream systems protected, ballast water free from invasive species, and RO membranes safe from upstream contaminants.

Filtersafe’s patented filtration technology all started with a vision to engineer a dedicated seawater durable filter that could handle filtration of microscopic organisms without letting the microscopic organisms through or clogging. After years of R&D our engineers created our unique smartweave screen, utilizing a patented manufacturing and sintering process that places our screen leaps and bounds above the alternatives.

By using a combination of weave wire filtration screens, protective screens, and a reinforcement layer, the innovative, highly effective screen filters out sediment and microorganisms, providing invaluable filtration support no matter where it’s installed.

Why It’s Important

As the heart of a filter, the screen provides two key benefits that make or break the functionality of the filter – it’s ability to filter out particles down to the designated micron and its ability to work without clogging.

wedge wire candle filter with debrisIf a filter can’t be trusted to filter down to the required micron level, many problems can occur. In an industry such as ballast water filtration, allowing organisms in the ballast tank can cause a ship to be in non-compliance with the International Maritime Organization’s D-2 regulations, and result in heavy fines for shipowners. In agriculture, it can result in sediment getting through to the drip irrigation lines and clogging the pipes and nozzles, resulting in expensive maintenance. Every filter request comes with a request to filter down to a specific micron level because anything bigger than this size will cause problems downstream. It’s imperative that end users can trust that their filters are filtering down to the level requested.

The second issue, clogging, is deeper than just the screen stopping because of a clog. Clogging can also refer to any unexpected reduction in the filter’s flow rate, which can cause cascading problems. Firstly, many filters clean based on the concept of differential pressure – that is the pressure inside of the filter is higher than that outside and this difference in pressure triggers the screen to be cleaned. If the screen cleaning mechanism can’t properly remove the debris building up on it, the buildup of debris can reduce the clear opening of the filter mesh and significantly reduce the flow through the filter. Even before it clogs completely, this phenomenon can reduce flow through the filter by up to 80 or 90%, effectively rendering the filter clogged even though it still can pass the process fluid.

On a cargo ship this reduction in water can slow or even halt the loading or unloading of cargo, as the ship can become dangerously unbalanced as products are moved on and off and there isn’t a respective change in balancing ballast water. The additional time in port not only throws of the ship’s schedule down the line, but can result in expensive additional docking fees while in port. In many industrial applications a clogged filter can simply shut down the process its involved in – in a food production facility this means stopping production, but if the filter is involved in a HVAC/cooling tower application, the particles that aren’t filtered out can cause corrosion within the system, or even more dangerous cause the system to overheat and shutdown as the vital cooling water isn’t being provided.

Now that we understand how important a properly functioning screen is to various industries, let’s learn more about how Filtersafe’s smartweave screen works.

How It Works

The basis for Filtersafe’s smartweave screens is our exclusive weave-wire mesh layer. This is the layer that determines the micron level down to which the filter filters, and can range anywhere from 10-500 microns, depending on the application. In order to enhance the strength of the screens (and we’ll see below flimsy screens are a real problem), the mesh layer is covered on either side by a protective layer. In addition, on the outside of the screen is an additional perforated reinforcement layer, for enhanced durability.

Filtersafe's 4 layer sintered screen

In order to keep the 4 layers compact and without rubbing (which can lead to wear and tear of the individual layers and compromises the filtration integrity and can also encourage corrosion within the filter screen) we have a unique sintering process, which allows our 4 layer screen to be less than 3 mm thick. The combination of the unique use of weave wire along with the additional protective layers also gives us an unrivaled effective screen area. This means that smartweave screens are able to trap a huge amount of particles while still maintaining a high flow rate (all within a small footprint). Lastly, Filtersafe is able to offer its proprietary screen technology in several different stainless-steel varieties including – 316L, 904L, and SMO254, depending on application requirements.

What is Sintering

Sintering entails heating elements of the 4 layers so that the metals of each layer bond together, without the use of any bonding agent or other external materials, and without actually melting the metal. Sintering produces a secure, reliable bond between the layers, and is especially suited to wire mesh, as it allows each wire to be securely attached in place at the same time. This is especially important as the numerous strands of wire can easily become loose and start fraying if not properly secured together – threatening the integrity of the filtration element cut point.

A Closer Look At Other Screens

The smartweave screen technology especially stands out when compared to the other screen technology options available. Let’s see how smartweave compares to the competition.

Floating weave wire vs smartweave sintered

Floating weave wire screens are similar to our smartweave screens in that they both contain weave wire and therefore have exceptionally high open area and higher flow rates than other screen options, while trapping 8 times more organic matter than wedge wire filters – however the similarities end there. Floating weave wire screens are a popular choice as they are much cheaper to manufacture than our sintered alternative, and therefore cheaper to buy. However, the cost savings in the short term quickly result in expensive problems for buyers.

The screens are called ‘floating’ because the screen layers aren’t sintered together and a cross-section looks like they are floating atop one another. Each layer of the Floating weave wire screens needs to be more robust because it can’t rely on the strength it neighboring layers which leads the overall width of the screen to be 12 mm thick or more with the actual fine filtration layer (working mesh) placed further away from the surface of the screen and the gap between the inner protection mesh and the working mesh can be 2.5mm or more allowing high slippage flows when being cleaned. Alternatively, smartweave screens are only 3mm thick with the working mesh being only 0.5mm away from the inner protection mesh. This increased thickness between the layers can make it harder for nozzles to properly clean the screen (an issue discussed in greater depth in our article about our patented nozzlex technology). Aside from the problems their thickness can cause with cleaning, as the screen layers ‘float’ they can move with changes in pressure within the filter, rubbing against each other. This can cause two problems – corrosion from the steel rubbing and reduced integrity of the weave wire layer which puts the filtration degree in jeopardy. Just one small hole in a screen changes the filtration degree of the entire screen.

Candle filters vs weave wire

Candle filters get their name from the long, tubular shape of the filter. These types of filters are normally wedge wire and rely on metal barriers to filter water and are cleaned through backflushing. While theoretically candle filters are supposed to be able to filter to a finer degree, the backflushing process can allow fine particles to come through. Unlike precision nozzles which suck off debris at the point of nozzle contact, backflushing reverses the flow of water to clean and the force of the reversed flow can weaken the filter’s welds over time,  reducing the durability of the filter. In addition, when fine filtration is required, the open area and porosity of the filter decrease dramatically, resulting in a much lower flow rate.

As discussed above, because smartweave screens are sintered, the layers of the screen don’t rub together, resulting in enhanced durability.  Weave wire screens can also be used on-line or in-line, while candle filters can only be in-line. Weave wire screens also have up to 6 times the open area of wedge wire, resulting in a higher flow rate that can be incredibly valuable if time is of the essence (such as when you are trying to fill up a ballast tank while unloading cargo, or are filtering water at a desalination plant for hundreds of thousands of people). Lastly, while more superficial, weave wire screens tend to leave water looking cleaner, even with larger filtration degrees.

Screen vs sand filters

Sand filters are one of the oldest technologies that are still in use. Sand filters are a common choice when the user wants to remove suspending particles and don’t require a high flow rate. They can be economical choices, but overall, have many cons when compared to automatic screen filters. The table below gives a clear overview on the benefits automatic screen filters have over sand filters.

FeatureSand FilterFiltersafe Filter



External Backwash Pump


Not needed


May be Necessary

May be Necessary

Clean water for Backwash


Not needed

Filtration Degree

25 microns and above (Unless chemical is used)

25 microns and above (Unless chemical is used)

Downtime for Backwash \ Flushing

10 to 20 minutes. System isolated for backwashing unless with
standby unit.

Flushing doesn’t affect system flow.

Approximately 30 seconds for full recovery.

Amount of Backwash water

Easily 6% of total flow

Less than 1% of total flow

Media Replacement


Not needed

Chemical Use

Yes, to achieve fine filtration

No chemical use


Let smartweave Filter For You

smartweave works to its full potential when paired with our nozzlex proximity nozzles, and results in our EVERCLEAR automatic filtration cycle technology. The EVERCLEAR autonomous self-cleaning filtration cycle works with low operating pressure, minimal water for flushing, and is NOT a backwashing sequence, for 100% screen cleaning every cycle.

Excelerate Exemplar Filter Installation: Video Case Study

Discover why Excelerate Energy chose the Filtersafe filter (as part of a De Nora BALPURE BWMS) for their challenging FSRU installation needs. Download the case study.

About the BWMS End User

Excelerate Energy owns and operates one of the largest fleets of Floating Storage Regasification Unit (FSRUs) in the industry and has over 15 years of development, construction, and operational experience. The company’s FSRUs are permanently moored to a docking facility at a location close to a market access point and tailored to fit specific environmental requirements.

For its latest charter, the FSRU Exemplar, Excelerate Energy needed a high-capacity ballast water management system (BWMS) capable of ballasting in the most challenging harbor conditions. To ensure efficient operations, the vessel needed a solution that could provide a flow rate of 5,000 m3/h and fit

into the limited space available in the engine room, to properly support the Exemplar’s 150,900 m3 storage capacity.

See our video case study:

Why they Chose Filtersafe

The BallastSafe Series features a modular design that allows for any possible configuration and is particularly helpful in retrofit installations. BallastSafe filters can be installed vertically or horizontally to provide the flexibility needed in tight spaces, and the vertical filter configuration operates in exactly the same manner as a horizontally positioned unit and to the same performance standard, whilst substantially reducing its area footprint. Filter orientation can be decided in as little as eight weeks before delivery.

Filtersafe’s automatic screen filters utilize unique, patented, and cutting-edge technologies to ensure the high-performance demands of the market are met. They are a dependable filter choice, are approved by all major class societies, and are approved to work with most IMO and US Coast Guard leading BWMS systems.

To learn more about the Excelerate Exemplar installation and the full details of the Filtersafe filter, please download our case study below.

Filtersafe Down Under: Our Australia & New Zealand Office

You can now find Filtersafe down under! 

Filtersafe’s latest international office and support center, Filtersafe Australia & New Zealand has opened in Adelaide, South Australia, servicing the entire Oceana region. Our Australia office specializes in filtration for Agriculture, Aquaculture, Mining, Industrial and other related applications, and brings unique solutions to these applications to meet the Australian market’s needs. 

For example, agriculture is the largest user of water from the River Murray System. Filtersafe has years of experience filtering water directly from rivers, reservoirs, and other dynamic bodies of water for use in irrigation. Filtersafe offers extensive experience in a variety of agriculture and aquaculture applications, including high-flow filtration, filtering water sources with high loads of TSS and organic matter, and other applications so important to corporate farms who rely on filters that run smoothly and won’t clog. 

Mining is another important industry that requires robust, proven filters that can work in the harshest conditions. Filtersafe filters have and are currently being used for various critical aspects of water filtration in mining, such as de-dusting, reuse, and treatment before discharge, and can be found operating reliably in the toughest climates, from Siberia to South America.  

These industries provide challenging water for filters as the water to be treated will have very high TSS and debris that can threaten the integrity of the screen. Filtersafe successfully not just passed but superseded a test done for the ballast industry, but is applicable to all industries, showing that even at 2,450 ppm TSS the filters do not clog. 

The team is led by David Thomson, the CEO. After working in filtration for decades, David was excited at the opportunity to build Filtersafe’s presence in Australia. He explains, “It is not often that the mechanical filtration industry, which is quite mature, has a big advancement, but Filtersafe’s patents and systems are a game-changer.” In addition to his roles as CEO, David is focused on bringing Filtersafe’s revolutionary technology to the corporate agriculture sector.  

Jamie Pickford brings his years of experience to serve Industrial applications. Jamie himself has spent 30 years in the water industry, working in South Australia, New Zealand, Queensland, Western Australia and Indonesia. During that time, he served in various management roles focusing on large industrial pumping and filtration projects for municipal, mining, aquaculture, agriculture, and industrial applications and will continue to use his expertise to show potential customers in these industries the benefits Filtersafe can bring to their applications. 

For Technical Sales & Support, Ronen Leyson rounds out the leadership team. His expertise is helping clients find the best Filtersafe product for their needs and providing support when needed. 

For more information on the products and services Filtersafe Australia and New Zealand offers to the region please reach out to or fill out our contact form here and we will get back to you.  

Filtersafe 2.0: The filtration experts for challenging waters

As Filtersafe approaches 20 years in business, we decided to take a deep look back at what has made us successful, and where we want to be heading. Over the course of the past year, we took time to self-reflect and identify our strengths so that we can continue to utilize them and see where we have the potential to grow. At the same time, we reached out and spoke to our clients, vendors, partners, and employees to help us get alternative points of view on the same questions.

Amongst the responses, there were three recurring themes that stood out, and that we felt a deep emotional connection to that touched on the answer of why we do what we do. We took these ideals and forged them into values that don’t just represent who we are as a company but also as a commitment for the future, that Filtersafe is and will always strive to be:

  • Committed to relationships
  • Leading the with expertise  
  • Driven by challenges

To help explain how these values touch in our daily function as a company we put together the following story: 

While we are still at our core a seawater filtration company founded to help protect the world’s oceans, we have grown to become a leader in the filtration of challenging water across the spectrum (fresh, brackish, reclaimed, etc.). Today, over 4,000 of our systems can be found installed on ships, in mines, in municipalities, on farms, on oil and gas rigs across the globe, to name a few locations.

With this growth, we decided it was time our brand was updated to reflect our growth.

As a company that heavily invests in R&D, we have significant developments that will be introduced to our markets in the coming year. This rebranding is done to reflect these developments and journey we are going through. This visual change may seem minimal, but they reflect the new additions and improvements to our product lines and processes that we’ve been making, and will continue to make as we continue to solve critical filtration challenges, together.

Ballasting Flow Rates: The True Cost of Delays & How to Avoid Them

In today’s maritime industry, ship owners and operators are required to make new, costly investments to ensure that vessels comply with the latest environmental regulations. This includes the Ballast Water Management Convention (BWMC), which requires most vessel owners to install and operate an effective ballast water management system (BWMS). Typical BWMSs have a primary treatment component, in most cases a filter, then a secondary treatment component to neutralize the organism found in the ballast water. With profit margins under pressure, and numerous products to choose from, many shipowners see BWMS and filter selection as a weighty decision with long-term CAPEX and OPEX implications.

To make a smart decision, it is essential that shipowners understand both the regulatory and technical benefits of specifying a BWMS that includes a suitable filter – one that promotes proper filtration to avoid ballasting delays and non-compliance with the BWMC.


Regulation and non-compliance

In order to comply with the International Maritime Organization (IMO) Ballast Water Management Convention and the additional US Coast Guard (USCG) ballast water regulation, it is essential to select and operate a high-performing BWMS to ensure long-term and reliable treatment of invasive aquatic species. In practical terms, most ships ballast in port or river estuary waters, where sediment is significantly higher than out at sea. This can significantly impact flow rates if a low-quality filter is installed, which can then extend ballasting times.


Flow rates impact finances

Ballasting rates for a vessel are designed alongside the rates of cargo loading and discharge. For vessels to safely load and unload cargo, the ballast pumps must be able to either load ballast water or discharge ballast water to maintain the stability of the vessel. The slowing of the flow during ballasting can have dangerous consequences for vessels during cargo discharge if the stability of the vessel becomes compromised, such as listing.

A decreased flow rate occurs for two primary reasons: firstly, during heavy loading, when filling the tanks to maximum capacity as quickly as possible, the filter will often go into continuous backflush and a significant portion of the water will be diverted through the backflush line. Secondly, filter loading and increased differential pressure across the mesh places a larger discharge head on the ballast pump, causing the pump to flow less water to the tank.

In reality, the time it takes to move ballast can range from 12 hours to nearly 90 if the filter is not designed for heavy loading. In comparison, a filter appropriately designed for a vessel’s loads and the waters where it will be ballasting may be able to move more than three times as much water than a filter that slows or clogs.

The exact amount of money that can be lost will depend on the market, the type of vessel, whether the vessel is in port, how busy the crew is, and what the costs may be for additional time alongside. However, as an example, a VLCC tanker earning a typical $36,000/day, every hour of delay can cost $1,500 plus any port charges. These costs can rapidly add up and should be kept in mind when considering CAPEX and OPEX for a BWMS installation.


The challenge of sediment

An additional factor that can decrease flow rates is the level of sediment being collected while ballasting. Two particular locations, the Mississippi River Delta and the Yangtze River, show exceptionally high Total Suspended Solids levels and present a particular challenge to many BWMS technologies.

Sediment is one of the critical factors in filter clogging but allowing sediments to accumulate has further implications to the vessel. The buildup in the ballast tanks between drydocking periods can create an unpumpable, permanent ballast that, if not removed, reduces the vessel’s cargo capacity over time.

For vessels contracted in the bulk and oil trades, this may affect the charter agreement and cause vessels to carry less than the obligatory cargo amounts as per the voyage plan, with potentially significant implications for a ship’s earning ability. Vessels are designed to carry a specific amount of cargo based on weight and displacement, so vessels ferrying around even a few inches of sediment over the entire bottom of ballast tanks can quickly see tonnes of additional weight added to their dead weight. This additional dead weight may offset cargo loads.

The choice of a BWMS and its filter is critical for shipowners and operators to avoid non-compliance and expensive ballasting repercussions. It must be economically sound, both from a CAPEX and long-term OPEX standpoint. The filter within a system has a big effect on its ability to perform effectively, efficiently and within the regulatory parameters. As such, it is an investment with potential implications for many company departments, including technical, operations and finance. This makes BWMS and filter selection a business critical issue.

For more information on this topic, please download our whitepaper on the cost of compliance here:

Filtersafe provides high performing BWMS filters for ConocoPhillips Fleet

Filtersafe multifilter installed on Polar fleet

Learn why ConocoPhillips chose the De Nora BALPURE® BWMS with Filtersafe filters for their entire Polar Vessel fleet.

ConocoPhillips, Alaska’s largest crude oil producer and the largest owner of exploration leases, operates a series of vessels traveling between Alaska and San Francisco. This west coast route has particularly challenging conditions due to widely ranging water quality, including high sediment waters in San Francisco Bay.

ConocoPhillips Polar route with Filtersafe filtersConocoPhillips recognized the need for high-performing ballast water management system (BWMS) filters to ensure regulatory compliance and operational efficiency. In 2015, the company invested in independent testing to assess and choose the right BWMS filter for the fleet’s operational route.

It was through this testing that they came to the conclusion to install the De Nora BALPURE® BWMS with Filtersafe filters across the fleet.

The BallastSafe BS300-T filter . The filter is designed to perform under high sediment loads in poor water quality areas and has a flow rate of 750 m3/hr. Due to the enormous size of the ships in the fleet, it was decided that in addition to 2 BallastSafe BS300-T filters, that 2 additional BallastSafe BS1204H filters should be added when the BWMS is installed in each ship.


Filtersafe solution

Most filters build a “cake” i.e. an uncleanable part of the filter created over time as a result of a decrease in water pressure in the filter system. For the filter to return to optimum performance levels, the filter must be manually cleaned. In contrast to most filters, Filtersafe’s solutions are the only technology available to the global shipping industry today which is self-restoring.

This means the filters have no uncleanable areas and are able to remove even the toughest build-up, with the filter returning to its original clean state after every heavy use in less than three minutes. For example, in the Shanghai Test our filter fully recovered from an unimaginable TSS load of 2,450 ppm in 182 seconds. 

Filtersafe has an exclusive, upgradeable cleaning mechanism that can be modified even after installation to improve cleaning efficiency. This means the filter can be configured according to the vessel’s trading waters and then changed as those trade routes are altered over the life of the ship. This is significant as it removes the limitations that ballast water management systems (BWMS) have traditionally placed on ships, allowing vessels to move between low and high sediment routes, such as the tankers navigating around high sediment areas of San Francisco, without being prohibited by filter performance.



The filter operated under various conditions for several months, monitoring and recording hundreds of hours of valuable operation data. The results of the tests demonstrated flow rates varying between 400-750 m3/hr. These rates were recorded during testing and varied according to inlet pressure levels and sediment loads, which reached as high as 400 Nephelometric Turbidity Units (NTU) (TSS 350- 400mg/L). The filter performed very well during high sediment loads, especially at known turbid locations such as the Shell Terminal in San Francisco Bay and the ports of Anacortes and Valerio in Washington, recovering quickly from the high dirt load conditions. In addition, the filter operated without the need for manual cleaning throughout the duration of the test.

Following the successful installation and the test results on board the pilot Polar vessel transporting fuels regularly between Alaska and other major energy producing ports along the North American West Coast, ConocoPhillips decided to install Filtersafe filters on the entire Polar fleet.

Following the initial test, all five crude oil tankers in the Polar fleet will feature filtersafe filters as an integral part of their BWMS, with 2 ships already past installation and commissioning and the rest with planned installation datesin 2022: Polar Endeavour, Polar Enterprise, Polar Resolution, Polar Adventure and Polar Discovery, as outlined above. Each vessel was assessed according to its ballasting needs to ensure the right filters and flow rates were chosen. Filtersafe also worked with a leading class society, the American Bureau of Shipping (ABS), to complete a successful remote pressure test survey to certify the filters ahead of installation to ensure the highest standards for ConocoPhillips.

To read more about the installation, please download the case study here:

What the Shanghai Test Results Tell Ship Owners About a Ballast Water Filter

Shanghai River with Muddy Water

Savvy ship operators know that the right filter is key to not only complying with IMO and USCG regulations but also to ensure that their ship can sail and ballast anywhere, in addition to costing or saving a ship money by how long it takes to filter and fill a ship’s ballast water tanks.

Shipowners and operators regularly ask Mr. Louis Peperzak (Technical Manager Ballast Water Services at Control Union) and his colleagues: “How am I supposed to trust that a ballast water filter will work in severe circumstances?” they continue: “since IMO regulations account for 50 mg/L of TSS but in Shanghai Harbor, TSS concentrations can reach up to 1,000 mg/L?”

They turned to Control Union specifically as they are a highly respected 3rd party certifier of various maritime QA/QC evaluations, including for ballast water management systems. The Control Union as a whole is a collection of international companies that offer certification in various industries, including marine and ballast water.

What is the ‘Shanghai Test’?

This is how Control Union came to create their ‘Shanghai Filter Test’, which seeks to mimic the muddy, turbid waters of the popular Shanghai Port. If a ballast filter could manage to filter the 1,000 TSS mg/L of suspended solids that can be found in the waters of Shanghai without clogging, then they could be confidant that their ship can sail to and ballast in any port without fear that the filter would clog from water with high total suspended solids (TSS).

The test puts water with mud the similar consistency and particle size distribution as the mud found in the Port of Shanghai through the filter at increasing amounts until the filter has less than 5% outflow and effectively clogs. Since the Port of Shanghai can have a maximum TSS of 1,000 mg/L that is the benchmark Control Union has set for whether a filter passes the test or not. If a filter can work at 1,000 mg/L without clogging, it is considered to have passed the test.

A clogged ballast water filter is an expensive and time-consuming problem for shipowners. A clogged filter means:

  1. The ballasting process must stop while the filter is cleaned, halting loading or unloading of cargo from a ship;
  2. Seafarers must invest manpower and spend time cleaning the filter instead of attending to their other important, onboard duties;
  3. More time spent in port, having to pay port fees, and time lost on the delivery route.

If a shipowner can know that a ballast water filter comes tested & certified by Control Union as having passed the test and not clogging at 1,000 mg/L of TSS, they can have more confidence in their entire BWMS. This means a certified ballast filter is also of interest to BWMS manufacturers and naval architects who help ship operators pick and install their BWMS.

Filtersafe’s Shanghai Test Results

Filtersafe sent 5 configurations of its ballast water filter to the Control Union location in the Netherlands for the test (a combination of 25 micron and 40 micron screens paired with standard, turbo and superturbo automatic self-cleaning options in a BS101 filter body).

Filtersafe is proud to announce that not only did all 5 of the configurations pass the 1,000 mg/L challenge, all filters were challenged with increasingly turbid water, up to 2,450 mg/L, and none of them clogged.

We invite you to take a look at the results yourself. You can download the Shanghai Test Report to receive an explanation in detail of how the test was conducted and the results of each of the 5 tests.

Please fill out the form below to immediately download your copy of Filtersafe’s Shanghai Test Report.

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