Exhaust Scrubber Alternative Proposed for IMO 2020

Fort Myers, Fla. (August 22, 2019) – January 1st, 2020 marks the beginning of the International Maritime Organization (IMO) regulation on sulfur emissions for the global maritime fleet.

Heavy Fuel Oil (HFO) or High Sulfur Fuel Oil has provided tankers and cargo ships with cheap and widely available fuel for decades.

This new regulation calls for vessels to adopt higher cost fuels with significantly less sulfur contents than the current 3.5%.

Although the regulation specifically calls for the use of low sulfur fuels, the rule was written to regulate emissions, not sulfur contents.

This has created a loophole that allows vessels to keep burning the preferable high sulfur fuel oil so long as they adopt the appropriate measures to suppress sulfur emissions.

This has brought exhaust scrubbers technology into the global conversation because it can do just that.

Once installed on a ship, exhaust scrubbers work to significantly reduce sulfur oxides and particulate matter in emissions.

This would allow vessels to keep or even benefit from the low and predictably dropping price of high sulfur fuel oil.

Unfortunately, demand for this technology far outweighs the world’s supply capacity leaving many ships with two options, adopt more expensive compliant fuels (ultra low sulfur fuel oil, marine gas oil, or diesel fuel) or pay for costly vessel conversions to Liquid Natural Gas (LNG).

This harsh reality has prompted AXI International to propose a new solution to better deal with the IMO’s 2020 regulation.

The Concerns of Exhuast Scrubbers

Before we get into the new solution proposal, we must better understand why an alternative to exhaust scrubbers or Exhaust Gas Cleaning Systems (EGCS) would be desirable.

Aside from the low availability and long lead times, scrubber technology is still considered to be in its infancy and can cost ship owners millions for installation and integration.

EGCS systems are also becoming a much-debated topic among environmentalists due to how its byproducts are being disposed of.

Many of the new exhaust scrubbers being installed are open loop systems that spray sea water over the exhaust fumes to wash out the sulfur oxides and particulate matter.

Once drained from the emissions chamber, the sea water, now full of emissions contents, is released into the open ocean.

Advocates for exhaust scrubber systems have argued its effects on the ocean are negligible while many others remain skeptical of such claims.

“Surely, scrubbers will reduce emissions to air, but it appears as it will just move the emissions to the sea instead.” – Ivar Myklebust, CEO of Höegh Autoliners

This has led to speculation on whether exhaust scrubbers could be the target of future, more stringent regulations.

If this were the case, thousands of multi-million-dollar investments to keep HFO could be rendered useless overnight.

Singapore, China and Fujairah in the United Arab Emirates have already started a ban on open loop scrubber systems.

There are fears that localized areas with higher shipping density may be vulnerable to higher discharge volumes leading to negative ecological impacts.

It is uncertain if other ports will follow suit with similar concerns.

The Benefits of Keeping High Sulfur Fuel Oil

New Very Low Sulfur Fuel Oil (VLSFO) is expected to be 25% more expensive than the current high sulfur fuel oil.

This rise in fuel costs will result in increased freight rates which can be expected to be passed down to end consumers.

With 90% of all global trade happening on our oceans, Goldman Sachs estimates this change could impact consumer wallets by nearly $240 billion in 2020.

With initial capital expenditures, an investment in exhaust scrubber systems could help ships owners dodge the hikes in fuel costs and even save them money should the price of high sulfur fuel oil drop like many predict.

Keeping heavy fuel oil could make certain vessels more competitive with lower freight rates and faster transportation times, another metric expected to be negatively impacted as ships attempt to lower fuel consumption.

AXI International’s new alternative could allow entities to remain competitive in 2020 without the huge risk in capital expense needed for exhaust gas cleaning systems.

An Exhaust Scrubber Alternative

AXI International suggests the better solution to emissions control and cost reduction lies in the pre-combustion stage of the engine as opposed to the reactive approach of exhaust scrubbers during post-combustion.

By modifying the rate determining step of the fuel during the combustion process, AXI International has demonstrated amazing results in emission reductions across the board along with increases in fuel efficiency.

This is due to the fuel being burnt more completely in the combustion chamber as opposed to creating excess byproducts we have come to know as harmful emissions.

A proprietary combustion catalyst lies at the heart of this solution and AXI International has developed a robust system to deliver it directly to the vessel’s fuel supply with intelligent auto dosing protocols.

Talks have already began surrounding the systems implementation for smaller applications but AXI is actively looking for partners in further testing on larger maritime vessels.

With a more complete combustion of the fuel, users can expect increases in efficiency and power on top of emission reductions.

 “These benefits are all tied together. If you are burning more of the fuel you can expect to extract more energy from the fuel and receive considerable increases in power and efficiency. Harmful emissions are also a direct result of unburnt hydrocarbons (fuel). If more of the fuel is being burnt, you can quickly deduce how it would correlate to reductions in harmful emissions.”

To go further, AXI International’s AFC Fuel Additives are already being used to restore much of the lost lubricity associated with ultra-low sulfur diesel.

AXI believes this additive injection system paired with its fuel additive could work to alleviate some of the coming ailments and offset some of the increased costs associated with the adoption of new distillate marine fuels.

Chemical fuel treatments or fuel additives are a proven technology that have been successfully utilized in many industries on a whole range of hydrocarbon-based fuels.

” …the application of residual fuel additives in the marine and power generation sectors to improve combustion or provide other benefits is not yet widespread… The combustion phase is one of the areas where marine residual fuel oil additives can be used to advantage” – Chevron

In automating the additive dosing process, AXI International hopes this will become a more feasible solution for marine vessels to gain a competitive edge in a IMO 2020 environment.

Addressing "Algae" in Diesel Fuel

There is nothing worse than opening your tank and seeing diesel fuel contaminated with “algae“.

If this fuel were ever to be used, it could wreak havoc on your fuel system.

You may be asking yourself how do I get rid of this “algae” and prevent it for good?

Luckily, we have the answers to those very questions.

In this article, we’ll explain what the “algae” really is, where it comes from, common methods to combat it, and best practices to prevent it for good.

Part 1:

Understanding the Problem

A Common Misnomer

In order to address “algae” in diesel fuel we must first understand the problem in its entirety.

It was a common misconception that the dark sludge growing in your tank is “algae”.

As a result, many still refer to it as such.

What you are actually dealing with is microbial growth.

How do we know this?

For starters, your fuel tank is far too dark.

Algae are plant organisms and they cannot survive without sufficient sunlight.

On the other hand, there are plenty of microbes (bacteria and fungi) that reside in your diesel fuel.

Graphic depicting different cartoon microbes

When water present in the diesel separates into a distinct layer below the fuel (phase separation), you may notice a dark layer begin to form.

A term often coined to describe this phenomenon is the “diesel bug”.

Graphic depicting the development of fuel contaminates in diesel fuel overtime

The interface between the diesel fuel and the water creates the perfect breeding ground for various bacteria and fungi to thrive.

The microbes live and proliferate in the water while consuming the hydrocarbons in the diesel fuel.

In time, the accumulation of microbes will form a visible biomass (rag layer) between the water and diesel fuel.

By-products and dead cells from the growing microbial communities also fall towards the bottom of tank to create a viscous sludge.

The Effects of Microbial Growth

The sludge by-product of microbial growth, when churned up, can clog any engine filter with ease.

A clogged engine filter, especially one clogged at a time of importance, can cause serious problems.

For example, data centers relying on diesel generators for backup power may experience unexpected downtime due to clogged filters.

This can result in costs of hundreds to tens of thousands of dollars a minute for maintenance.

On a smaller scale, clogged filters on boats can often leave owners stranded.

“The diesel bug may start on a microscopic level, but it is clear it can lead to macroscopic consequences.”

Part 2:

Common Solutions

Common Methods to Prevent “Algae” in Diesel Fuel

There are a lot of opinions on how to best prevent “algae”/microbial growth in fuel.

Some will push for the use of biocides which use hazardous chemicals to kill most of the microbes directly.

Others prefer fuel additives that pull water back up into the fuel to help prevent conditions (phase separation) best suited for microbial growth.

At AXI International, we understand that neither of these solutions are perfect for every situation, but recognize they embody the two methodologies for controlling microbial growth in diesel fuel.

You can either kill them directly or prevent the very conditions they thrive in.


Although initially effective, biocides are not the end all solution to microbial growth and sludge formation.

Placing health, safety, and environmental concerns aside, frequent use of biocides can create resistant microbes that no longer die upon application.

This is due to the fact that it is nearly impossible to sterilize diesel.

As a result, the surviving microbes, through means of natural selection, will exhibit increasingly resistant traits that will eventually render biocides ineffective.

Graphic depicting a biocides eventual ineffectiveness on microbes in diesel fuel

Part 3:

Best Practices

Removing Microbial Sludge

If microbial growth has progressed to a point that it is noticeable, no treatment mentioned will effectively remove the sludge.

In order to restore the fuel, you must employ a mobile fuel polishing service or system.

Mobile fuel polishing systems work by circulating the fuel out of the tank for filtration.

Graphic depicting periodic fuel polishing with a mobile fuel polishing system

These systems are designed to effectively remove both small and larger contaminates like sludge and can prevent microbial growth through the removal of water.

Beyond restoring the fuel, it is not recommended to use mobile fuel polishing as a long term preventative measure to “algae“/microbial growth when compared to other options.

Preventing Microbial Growth

In some cases, fuel additives that pull water up into the fuel by the means of an emulsifier can be an appropriate response to preventing microbial growth.

The additives address the problem at its source.

Without water, microbes cannot proliferate in the fuel.

By pulling the water into the fuel, it will eventually vaporize in the engine and exit out the exhaust.

In cases involving a Tier-4 engine, water emulsifiers will only create more problems.

Tier 4 engines feed fuel into the combustion chamber at extremely high pressures with very little tolerance for fuel contaminants.

Internals of an injector tips nozzle

Emulsified water, being much larger than the 2-4 micron injector openings, can cause abrasive wear and eventual failure of the injector tips.

Due to this reality, Tier 4 engines require a more technical solution.

Tier-4 Preventative Solutions

For Tier-4 engines, fuel maintenance systems are the best approach to prevent “algae”/microbial growth in the diesel fuel.

Fuel maintenance systems are permanent installations that work on a programmed schedule to regularly pull fuel from the tank to filter out contaminants.

Graphic depicting the installation of an enclosed and compact fuel maintenance system for automated fuel filtration

Unlike fuel polishing systems, fuel maintenance systems are better at maintaining the fuel as opposed to restoring or remediating it from a highly contaminated state.

By the same effect of fuel polishing systems, fuel maintenance systems prevent “algae“/microbial growth through the removal of water.

Tank Polishing Dramatically Improves with New Technology

Fort Myers, Fla. (November 29, 2018) – AXI International is disrupting the fuel maintenance industry with a slew of new technologies that simulate, improve, and measure tank cleaning effectiveness.

Through the use of powerful software, the company can now simulate the cleaning efficiencies of their fuel polishing systems on different fuel tank designs.

With these simulations, AXI has solidified claims that their patent pending technology, Multi-Point Flow Path, dramatically increases flow velocity and tank cleaning coverage in base/belly tanks compared to traditional fuel polishing configurations.

To take things a step further, the company has also begun integrating particle counters on their systems to provide real-time data regarding fuel cleanliness to international cleanliness standards (ISO 4406).

“Combined, these technologies bring AXI to forefront of the fuel maintenance industry by inspiring data driven design and producing data backed results.” – Jeff Poirier, COO

Multi-Point Flow Path

Traditional fuel polishing configurations feature a single point of pick-up to pull fuel into the polisher and a point of return to transport the newly clean fuel back to the tank.

The industry has considered this best practice for maintaining fuel cleanliness.

AXI International hypothesized and later proved this traditional approach was lacking in tank cleaning effectiveness, which lead to the creation of Multi-Point.

This upgrade adds multiple pickup and return points to increase the number of flow paths, average flow velocity, and total cleaning coverage in any given tank.

To both optimize and demonstrate the effectiveness of this upgrade the company invested in complex simulation software.

Computational Fluid Dynamics (CFD) Software

AXI uses computation fluid dynamics (CFD) software to demonstrate the fluid flow, velocity, and cleaning coverage of fuel polishing configurations of specific tanks.

Through these simulations, AXI has demonstrated the power of their Multi-Point Flow Path upgrade in contrast with traditional setups.

Leveraging this insight, the company has begun consulting on valve placement and tank design to better optimize fuel flow for maintenance purposes.

Particle Counter Integration

To further ensure a tank’s fuel is meeting the international standards for cleanliness (ISO 4406), AXI now integrates particle counters into their fuel maintenance systems as an additional option.

These particle counters use laser-based detection to identify the size and number of contaminant particles per 100 mL of fuel.

The result is a three number code used to determine the overall cleanliness of the fuel as defined in ISO 4406.

“By integrating particle counters, we are eliminating any guess work as to how clean the fuel actually is before and after polishing. Our system will read the data and react appropriately to ensure your fuel is always within spec.” – Jeff Poirier, COO

The Failure Chain: When a Power Outage Can Spell Downtime

For mission critical facilities, downtime is not an option.

When the power goes out, multiple systems must function in sequence for a smooth, uninterrupted transition to backup power.

If just one of these systems fails, the whole backup power system fails.

This is what we call the Failure Chain.

In this article, we cover how oversights in maintenance can lead to the dreaded Failure Chain and how you can prevent downtime.

Part 1:

When the Power Goes

Mission Critical Facilities

Mission critical facilities house any number of operations that, if interrupted, will cause substantial losses of revenue, reputation, and, in the worst cases, life.

This definition can include a large range of facilities such as:

When a power outage occurs, these facilities must rely on a seamless transition to backup power to avoid the damaging effects of downtime.

According to Gartner, even a lapse of just minutes could cost companies thousands of dollars, not including the loss of customer goodwill.

Uptime Statistics (2018)

The 2018 Global Data Center Survey compiled by the Uptime Institute reported infrastructure outages increased to 31% among respondents, a 6% rise from last year’s 25%.

A majority of downtime instances averaged at four hours with 50% of respondents reporting losses under $100,000 and 3% at over $10 million.

Chart Depicting the top causes of Data Center downtime in 2018

The leading cause of data center downtime were power outages, accounting for 33% of all reported cases.

Part 2:

The Failure Chain

The Backup Power System

The typical backup power system includes multiple components that combine into a coordinated system aimed at providing a seamless transition to and from backup power.

Graphic showing an automatic power transfer switch

The instant a power outage is detected, the Automatic Transfer Switch (ATS) shifts power draw to an uninterruptible powersource (UPS).

A signal is simultaneously sent to the backup power generator (usually diesel powered) to begin startup.

Graphic of a Uninterruptible Power Supply (UPS) system

To maintain power during the time taken to start the generator, the UPS acts as a temporary source of electricity.

These systems, usually large batteries, are relatively limited in both storage and output.

As a result, only critical functions receive power until the main source of backup power, the generator, is fully running.

Graphic of a Diesel Power Generator with base tank of contaminated fuel

It is at this point in the backup power chain that problems are most likely to arise.

Fuel is drawn out of the storage tank and into the generator.

If not maintained properly, the diesel fuel can carry contaminants such as:

With the implementation of High Pressure Common Rail (HPCR), an advancement in fuel system efficiency, the tolerance for fuel contaminants has significantly decreased to 4μ in size.

Any contaminant larger than 4μ can clog or, in the case of water, even blow injector tips.

To prevent this, diesel generators have filters to prevent such contaminants from reaching the injectors but with poor fuel quality these filters can clog quickly.

Once generator filters are clogged a facility is left with two options:

#1 Shutdown the generator for maintenance

In order to replace filters, the generator must be shut down for maintenance.

Graphic of a individual replacing a on-board filter on a diesel powered generator

If the facility is relying on this generator for power, downtime is unavoidable.

#2 Bypass the filters

By bypassing the filters, there is nothing preventing the contaminated fuel from clogging or even blowing the injector tips.

Internals of an injector tips nozzle

Clogged injector tips will produce inefficient spray patterns which can result in:

Blown injector tips require immediate shut down for replacement and maintenance.

Either way, contaminated fuel significantly increases the risk of damage to the generator and downtime for the facility.

Part 3:

A Proactive Response

Addressing Fuel Contamination

Your backup power system is only as reliable as its weakest link.

Addressing fuel contamination is quickly becoming the standard for mission critical facilities.

AXI International provides two approaches to keep your diesel fuel emergency-ready:

#1 Fuel Polishing

Scheduled fuel polishing can be achieved internally with the purchase of a Mobile Fuel Polishing System (MTC) or outsourced to a fuel polishing company.

fuel polishing stored fuel to prevent downtime

With this approach, a mobile fuel polishing system is brought to your fuel storage tank.

Fuel is then pumped through the system where water, sludge, and particulate are filtered from the diesel fuel.

It is recommended you test your fuel regularly to ensure it remains within ISO cleanliness standards.

#2 Fuel Maintenance – Recommended*

Compared to fuel polishing, fuel maintenance systems are the more proactive approach to ensuring fuel cleanliness.

These permanent systems run automatically on a programmed schedule to maintain fuel quality indefinitely.

Much like dialysis, fuel maintenance systems pull contaminated fuel from the connected tank(s) for filtration and return clean fuel back to the tank(s).

fuel maintenance system for mission critical downtime

Ultra Low Sulfur Diesel (ULSD): the Good, the Bad, and the Rusty

You have probably heard mixed reviews about ultra low sulfur diesel (ULSD).

Some say it is great for the environment.

Others claim it causes more problems than it solves.

If you are looking for an unbiased take on what exactly is going on, you are in the right place.

Below we will cover why ULSD exists, its benefits and disadvantages vs. traditional diesel, and what you can do to protect your equipment in response to these changes.

Part 1:

ULSD: A Timeline

Clean Air Act Amendment (1990)

Congress passed the Clean Air Act in 1970 as a means to reduce harmful emissions from automobiles.

In 1990, it amended the Clean Air Act to require stricter emission reductions of:

The amendment also included, among other things, stricter tailpipe emission standards and emission testing procedures.

Concurrently, the EPA started imposing sulfur content limits in diesel fuel in an effort to specifically target sulfur oxide emissions.

Highway Diesel Program (2001)

In 2001, the EPA finalized a federally-mandated program called the 2007 Heavy-Duty Highway Diesel Program.

This program was established to further lower emissions from highway diesel engines.

Effective June 2006, the maximum sulfur limit in diesel decreased from 500 to 15 parts per million (ppm).

Chart of sulfur content (ppm) in on-road diesel overtime

This reduction marked the switch from Low Sulfur Diesel to Ultra Low Sulfur Diesel.

Clean Air Off-Road Diesel (2007)

Shortly after the highway diesel program’s inception, the EPA issued the Clean Air Non-Road Diesel – Tier 4 Final Rule.

This rule mandated sulfur reductions for off-road diesel engines, effective 2007.

Chart of sulfur content (ppm) in off-road diesel overtime

As a result, the maximum sulfur limit in off-road diesel fuel initially dropped from 3,000 to 500 ppm in 2007, and then again from 500 to 15 ppm in 2010..

Part 2:

ULSD: The Good, The Bad...

Emission Reductions

Since the 1990s, the EPA has mandated an overall 99.7% reduction in fuel sulfur content.

It has done so in order to cut diesel fuel emissions and pollution.

Sulfur oxides (SOx), specifically SO2are a threat to public health and the environment.

sulfur oxides and the threat to public health

Health concerns related to exposure from SOx include respiratory problems and lung damage.

SOx also causes environmental harm in the form of tree, plant, and stone damage, acid rain, and reduced visibility (haze).

The less sulfur content in fuel, the less polluting SOx emissions that fuel will release.

The Change in Fuel Chemistry

Reducing sulfur content greatly alters the lubricity and overall chemical composition of diesel fuel.

Refineries use severe hydrotreating to remove sulfur from diesel fuel.

Hydrotreating affects diesel fuel in the following ways:

Increases production costs

Fuel economy decreases by an estimate of 1%.

According to the EPA, severe hydrotreating increases fuel production costs by 5 to 7 cents per gallon.

However, these costs may be significantly higher depending on market, distribution, and other production factors.

Part 3:

ULSD: The Rusty

Same Tank, Different Fuels

In 2007, pollution awareness and prevention was on the rise as emission mandates came into full effect.

Since then, fuel tank corrosion damage has hit an all-time high in both gasoline and diesel fuel tanks.

ULSD fuel tankers labeled with ULSD and ethanol describing switch loading

This is because fuel hauling tanker trucks participate in something called switch loading.

For example, a truck could be hauling ethanol-based gasoline one day and ULSD the next.

ULSD causes fuel tanks to rust because of the increased water content and retention

This due to ULSD having a higher affinity to water than traditional diesel.

Water is essential for microbial growth.

However, as the EPA has confirmed, accelerated tank corrosion occurs when ULSD blends with small quantities of biofuel.

Therefore, when ULSD combines with ethanol, or other types of biofuel, even in small quantities, a problematic chain reaction occurs that not only accelerates tank corrosion but can also pose a risk to backup power systems:

ULSD problem flow chart that come from the increased microbial growth and sludge from using ULSD

Part 4:

ULSD: Problem Prevention

Addressing Low Sulfur

To combat problems with ULSD effectively, including decreased lubricity, energy density, and fuel economy, use of broad spectrum fuel additive  is considered best practice.

fuel additive can restore many of the lost properties of diesel while continually reducing emissions.

This is achieved through a fuel catalyst which allows for a more complete combustion of the fuel.

Benefits of using a fuel additive can include:

Preventing Corrosion & Downtime

As previously discussed, tanks containing ULSD have corrosion problems.

If ULSD mixed with biofuel during transportation, those problems will manifest at an accelerated rate.

To combat these issues, along with the formation of sludge, clogged filters, and downtime, you have to look at the chain of events that lead to these outcomes.

In this particular case, everything traces back to microbial growth.

Microbes that proliferate in diesel fuel love areas where water and fuel meet.

ULSD microbial growth from fuel contamination image

If you remove water, you effectively halt microbial growth along with the development of previously mentioned problems.

So how do you remove water?

You have two options:

#1 Hire a mobile fuel polishing company

A mobile fuel polishing company will bring specialized equipment to your location and filter out water, particulate, and sludge from your fuel.

Graphic depicting periodic fuel polishing with a mobile fuel polishing system

Note: Without a permanent installation, like a fuel maintenance system, it is recommended you test your fuel regularly to prevent future contamination due to condensation of new water or introduction of new fuel to the tank.

#2 Invest in a fuel maintenance system

A fuel maintenance system is a permanent installation that regularly maintains the fuel by removing water and other contaminants. These solutions run automatically.

Graphic depicting the installation of an enclosed and compact fuel maintenance system for automated fuel filtration

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