Open-Loop Scrubber

+250 marine water treatment installations for closed-loop scrubbers.

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Open-Loop to Closed-Loop Scrubber Conversion

Working with leading scrubber manufacturers, shipowners, and shipyards, LiqTech has many years of experience providing sustainable marine scrubber wastewater treatment systems for closed-loop scrubbers.

Do you have a vessel equipped with an exhaust gas cleaning system (scrubber)? Do you want to be future compliant with IMO regulations and save the ecosystem?

We are ready to convert your open-loop scrubber into a closed-loop system or hybrid scrubber. It is a compliant solution that allows vessels to operate on heavy fuel oil (HFO) and discharge clean water. With over 20 years of experience in the filtration industry and +250 marine scrubber wastewater treatment systems installed, we can provide you with an IMO-compliant scrubber water treatment solution.

Open-loop scrubbers have been subject to much debate, as they produce large amounts of wash water effluent, which is discharged into the sea, usually without any treatment. In open-loop mode, scrubbers discharge sulfuric wash water warmer than ambient seawater and contain suspended particulate matter, PAHs, and heavy metals. By converting into a closed-loop or hybrid scrubber with an open-loop retrofit, you can operate in zero-discharge mode (water reuse) or allow clean water for discharge without the pollutants that damage ecosystems and harm wildlife. Sludge and wastewater (bleed-off water) can be stored onboard and discharged shoreside.

Be future compliant with a LiqTech open-loop scrubber conversion solution.

The IMO is already working on an approved work plan focusing on harmonizing the rules for scrubber wash water discharges. They have sharply downgraded the limits of allowed sulfur content in marine exhaust gasses from 3.5% m/m to 0.5% m/m in the IMO 2020 regulations. The strict regulations are globally applied to all sizes of ships. Furthermore, in the Emission Control Areas, the upper limit for sulfur content in the marine exhaust is a maximum of 0.1% m/m. With an open-loop scrubber conversion from LiqTech, you will be able to comply with both the IMO regulations and the Emission Control Areas and be prepared for the future. Learn more about the IMO Sulfur Cap.

Our expertise in the marine scrubber industry and wastewater filtration will help you make growth sustainable – both concerning profits and the environment.

  • Future compliant with IMO regulations
  • Save the ecosystem
  • Operate in zero-discharge mode or discharge clean water
  • Work with marine and filtration experts
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Open-Loop Scrubber Bans

It is time for a scrubber conversion to closed-loop mode.

Many countries around the world are already banning the use of open-loop scrubbers in specific ports or territorial waters, including China, the United States, Singapore, France, Portugal, India, Spain, Egypt, Germany, Panama, Malaysia, Pakistan, UAE, Bahrain, Gibraltar, Belgium, Ireland, Scotland, Norway, Sweden, Lithuania, Bermuda and many more to come. If a vessel with an open-loop scrubber wants to enter some areas banning open-loop scrubbers, it will have to convert to a hybrid scrubber or a closed-loop scrubber. As an alternative, the vessel can switch to a more expensive compliant fuel containing less sulfur.

See the list of areas where open-loop scrubbers are banned.

  1. Open Loop Scrubber Ban World Map Liqtech Water

Proven Solution

1 years of experience in the filtration industry
230 marine scrubber wastewater systems installed worldwide

Work with Filtration Experts

Why convert from open-loop scrubber to closed-loop?

  • IMO regulations
  • Environmental footprint
  • Environmental image
  • Sustainability
  • UN Sustainable Development Goals
  • Closed-loop systems can spend more time in ECA zones and on port
  • Can use lower costing HFO (Heavy Fuel Oil) all of the time

Why choose LiqTech?

  • Many years of experience with treatment development for scrubber applications
  • Years of experience in installations and commissioning onboard vessels
  • Have in-housing specialists regarding open/closed-loop scrubbers and WTU
  • Complete production setup
  • Marine experienced project managers
  • References with all significant marine companies
  • Worldwide service setup
  • End-to-end qualified professionals
Marine Scrubber Wastewater Filtration Process Liqtech

Filtration Process for Marine Scrubbers

With a LiqTech open-loop scrubber conversion solution, our marine scrubber wastewater treatment system will treat the wash water from the scrubber tower and remove harmful elements from the combustion process, such as heavy metals, polycyclic aromatic hydrocarbons (PAH), and particulate matter (PM).

Afterward, the wash water is sent back to the scrubber tower for reuse. This enables the scrubber to run in a closed-loop mode with no scrubber waste discharge water overboard. A water monitoring unit is attached to continuously monitor and control pH, temperature, turbidity, and PAHs in relation to IMO regulations on scrubber waste discharge water. Instead, the SOx particles are filtered and concentrated in our silicon carbide membranes and further dewatered in a filter press or liquid sludge, providing bulk dry/wet waste discharge to a waste handling station while in port. By selecting a filter press solution (optional), a dry filter cake consisting of up to 80% dry matter is easy to dispose of while in port. By scrubbing the exhaust gas, 98% of sulfur is removed from the exhaust gases.

Liqtech Modular System Design Industrial Wastewater

Modular Design for Flexible Installation

With a LiqTech system, you get a flexible, modular solution, perfect for open-loop retrofits and new builds due to the design. The LiqTech system is compact, meaning that it solely takes up a small physical footprint of your vessel. If you want to increase capacity after installation, it is easy to add more systems if needed. A water treatment unit is highly efficient, ensuring thorough and high-quality scrubber wastewater treatment compliance with current and future regulations.

  • Separation of filter skid for ease of installation
  • Possibility to increase capacity
  • Low maintenance

The scrubber wastewater treatment system consists of:

  • Coarse pre-filtration
  • Fully automated SiC membrane system
  • Module for dewatering of membrane reject

Talk to an Expert

Please do not hesitate to contact us if you need help with a liquid filtration system.

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Your Success Is Our Success

In LiqTech we are experts in advanced membrane filtration technology for the purification of liquids and gasses. We deliver the know-how you don’t need to have – and deal with processes you don’t need to worry about.

We are a highly specialized business. Sharply focused on the industries where we believe our technology and application expertise can make the greatest difference. Flexible set up to deliver to your special needs – wherever you are. And proud to be pioneers when it comes to solving complex filtration challenges.

Our advanced membrane filtration systems help to ensure a high-quality end product; they also work to optimize your production. By removing treatment steps and protecting other equipment upstream and downstream. Ensuring an efficient and reliable operation.

When you choose us as your liquid filtration system provider, we would like you to think of us as your partner.