Connect with us

Business

ABS: Lessons learned from scrubber installation and operation

Scrubbers have been operating in marine environments for almost 30 years, so owners were not exactly entering a brave new world of technology, says ABS.

Admin

Published

on

CM1

The American Bureau of Shipping (ABS) recently released a post highlighting the challenges and possible solutions that were experienced by operators installing and operating exhaust gas cleaning systems.

At the beginning of this year, the IMO’s global sulfur cap on marine fuels entered into force and shipowners who chose the SOx scrubber pathway to compliance began the modern era of emissions reduction.

Scrubbers have been operating in marine environments for almost 30 years, so owners were not exactly entering a brave new world of technology. But any time a new technology is integrated into an individual vessel’s operating system, lessons are learned; and these lessons create a knowledge base that operators with less experience with scrubbers can draw from.

Leading class societies have been supporting scrubber integration in the marine environment since their first application. ABS, for one, has gathered the depth of market intelligence required to help owners to improve the process of installing and operating most scrubber systems.

Lessons have been learned about everything from installation and commissioning to the most common hardware failures for operating systems, and the type of consumables that are typically needed.

In this post, we will discuss some of the key issues associated with the installation and operation of scrubbers. But for a comprehensive list, please download ABS’s guide, practical considerations for the Installation and Operation of Exhaust Gas Cleaning Systems.

In commissioning SOx Scrubber systems, there can be challenges associated with extensive test periods, usually the result of an owner/operator having limited test plans and/or pre-commissioning work. This may be relatively intuitive, but following an approved test plan and completing the pre-commissioning activities are the fastest way to avoid these problems.

Another recurrent problem we are seeing, specifically during the installation process, is when washwater is carried over with the exhaust gas. This is commonly the result of unsuitable or inefficient flowpaths for the exhaust gas and can be resolved by optimizing the flowpath and/or modifying the design of the demister, which removes liquid droplets from the vapor stream.

Below are some more symptoms that operators are experiencing, and potential solutions:

HIGH EXHAUST BACK-PRESSURE:
This is likely due to either undersized scrubbers, sharp bends in exhaust piping, water-spray resistance, or a failure of the bypass-isolation valve interlock. Ultimately, the system’s design usually can be improved through simulations that identify the potential sources of back-pressure.

INTERRUPTED OPERATIONS
In the case of washwater supply, the problem can be caused by clogged filters in the supply piping. But when frequent operational interruptions become problematic, it is constructive to thoroughly examine your redundancy options. A failure mode and effect analysis can support this process.

NON-COMPLIANT PERFORMANCE
(eg., washwater pH value, SO2/CO2 ratio): These symptoms could be due to inadequacies in the washwater, low alkalinity in the water supply or simply an ineffective water-spray pattern. Improving the overall design, a process that can be verified through the use of computation fluid dynamics modeling, and verification of alkalinity levels in the water supply may resolve the issue.

POOR RELIABILITY OF MONITORING SYSTEMS
(including instrument malfunction): These symptoms can be caused by many issues, including the simple fact that the monitoring system may not be designed for marine applications. Other possible causes include that it may not be calibrated or installed correctly. Start by ensuring that the monitoring system is approved for marine use, and then follow the manufacturer’s instructions for calibration and maintenance.

HARDWARE FAILURE
When a SOx Scrubber system suffers a hardware failure there can be multiple causes. Below are some that industry-operating history suggests owner/operators may want to consider investigating when searching for solutions:

  • The sampling tubing may have become clogged, preventing accurate readings of SO2/CO2 ratios in the exhaust gas
  • The pressure transducers at the bottom of the pipe run may have become clogged with debris because the sensors were located in the wrong places
  •  The demister in the scrubber chamber may have malfunctioned due to a build-up of deposits
  •  Defective welds on piping system could have allowed washwater to leak
  •  Low-grade stainless steel (e.g. SS316 for fittings inside the scrubber chamber) may not have held up to       the corrosive operating environment
  •  The metallic pipe section on the side shell used to discharge washwater also may be corroded
  • The air pump that samples exhaust gases may not be working properly
  •  The scrubber’s uptake damper cannot be operated in manual mode
  •  The mechanical seals for the washwater feed pumps may have failed
  • The automation controls for printed circuit boards may have failed

MAJOR INCIDENTS CAUSING ENGINE SHUTDOWN AND DAMAGE:
History has taught the industry that most costly asset failures are the result of human error. The actions may be well-intentioned, but crews need to be fully trained to operate specific systems and to discourage any efforts to operate them in a mode that would disregard the control system, or manufacturer recommendations for upkeep.

In one recent event, a main engine stalled due to high backpressure after a scrubber by-pass damper failed to open when the scrubber uptake damper was closing. The programmable logic controller that was designed to control the interlock of the by-pass and uptake dampers had failed. Regular maintenance and testing in accordance with manufacturer’s instructions could have identified the problem.

The incident made clear that safety features require regular maintenance and testing in accordance with the manufacturer’s instructions, and that crews in charge of any system need to be familiar with basic starting procedures, such as checking damper positions and safety features.

In general, the industry has learned a lot about exhaust-gas scrubbers in the 30 years since they were first used in marine applications. The average owner may have become relatively familiar with the individual systems they chose to use.

However, leading class societies such as ABS will have learned the lessons from many systems, and have the depth of knowledge to help owners with any challenges they may face.

 

Photo credit: Cameron Venti from Unsplash
Published: 7 October, 2021

Continue Reading

Alternative Fuels

Yang Ming orders six LNG dual-fuel, ammonia-ready containerships from Hanwha Ocean

Each of the six new vessels will have a capacity of up to 13,650 TEU and feature LNG dual-fuel propulsion and Ammonia Fuel Ready specifications.

Admin

Published

on

By

Yang Ming orders six LNG dual-fuel, ammonia-ready containerships from Hanwha Ocean

Taiwanese shipping firm Yang Ming Marine Transport Corporation (Yang Ming) and South Korean shipbuilder Hanwha Ocean on Wednesday (2 September) signed a shipbuilding contract for six 13,000 TEU class LNG dual-fuel container vessels. 

The contract was signed by Dr. Chuck Tsai, Chairman of Yang Ming, and Mr. Charles Kim, CEO of Hanwha Ocean. The vessels are scheduled for delivery between 2028 and 2029. 

They will complement Yang Ming’s existing fleet of 10,000+ TEU vessels and serve as key vessels on East-West services, with deployment flexibility across trade lanes connecting Asia with the East and West Coasts of North America, South America, and the Mediterranean. 

Each of the six new vessels will have a capacity of up to 13,650 TEU and feature LNG dual-fuel propulsion and Ammonia Fuel Ready specifications.

“As Yang Ming transitions toward net-zero emissions, LNG provides a relatively mature and economically viable alternative fuel solution, capable of reducing greenhouse gas emissions by approximately 20%,” the company said. 

“At the same time, ammonia can serve as a carbon-free fuel by utilising converted LNG storage facilities, while offering relatively lower conversion costs and comparatively well-developed supply chains and infrastructure. The Ammonia Fuel Ready design will therefore provide Yang Ming with greater flexibility in responding to increasingly stringent international regulations on greenhouse gas emissions.”

In addition, the vessels will be equipped with Type B LNG fuel tanks with a design pressure of 1.0 bar to enhance the safety and efficiency of LNG operations, together with a range of energy-saving technologies, including Wind Shields, Rudder Bulbs, Pre-Swirl Stators, and Shore Power Systems. Smart ship technologies and cybersecurity protection features will also be incorporated to enhance operational efficiency, safety, and reliability while effectively reducing fuel consumption and greenhouse gas emissions.

Deliveries under Yang Ming’s next-generation fleet optimization plan commenced earlier this year. By 2030, a total of 24 new vessels are expected to enter service. 

This includes 18 LNG dual-fuel vessels—comprising five 15,500 TEU, seven 16,000 TEU, and the six 13,000 TEU vessels under this contract—alongside six 8,000 TEU methanol dual-fuel-ready ships. 

 

Photo credit: Yang Ming Marine Transport
Published: 4 September, 2026

Continue Reading

Alternative Fuels

LR, China’s MARIC unveil tanker concept ready for three future bunker fuels

Both secured AiP for a new 114,000 DWT product and crude oil tanker designed to accommodate future conversion to LNG, methanol or ammonia.

Admin

Published

on

By

LR, China’s MARIC unveil tanker concept ready for three future bunker fuels

Lloyd’s Register (LR) and the Marine Design and Research Institute of China (MARIC) on Thursday (3 September) have secured Approval in Principle (AiP) for a new 114,000 DWT product and crude oil tanker designed to accommodate future conversion to LNG, methanol or ammonia.

Announced at SMM 2026, the concept addresses one of the biggest investment challenges facing shipping today: the need to develop vessels and capabilities that can support a range of alternative fuel options and pathways as technologies, infrastructure and regulations evolve.

While LNG is already a mature fuel pathway, methanol and ammonia remain at an earlier stage of development, with questions around global fuel availability, infrastructure development, economics and long-term adoption.

The 114,000 DWT tanker concept has been designed as a product and crude oil carrier that can accommodate future conversion to LNG, methanol or ammonia as technologies, regulations and fuel supply chains mature. By incorporating conversion readiness at the design stage, the concept aims to reduce future retrofit complexity and provide owners with greater confidence when planning long-term fleet investments.

The design concept was reviewed against LR’s July 2026 class rules and regulations, including requirements relating to ships using gases and other low-flashpoint fuels, alongside relevant IACS Common Structural Rules for oil tankers. Final classification and statutory approval remain subject to full compliance with all applicable rules and regulations.

Theo Kourmpelis, Global Business Director for Tankers, Lloyd’s Register, said: “Shipowners are being asked to make major investment decisions today despite continued uncertainty around which fuels will dominate in the decades ahead. Alternative fuel solutions each offer potential pathways to compliance, but fuel infrastructure, regulation and economics continue to evolve at different speeds around the world.

“Designs that preserve flexibility will be critical in helping owners manage risk while preparing for multiple future scenarios.”

Si Nan, Marine & Offshore Marketing Department Vice Director, MARIC, said: “As the industry explores different decarbonisation pathways, shipowners need vessel designs that can adapt alongside technological and regulatory developments. This concept was developed specifically to provide greater fuel flexibility and long-term resilience, allowing owners to respond to changing market requirements without being locked into a single fuel strategy.

“Receiving Approval in Principle from Lloyd’s Register is an important milestone that validates the design concept and supports its future development.”

 

Photo credit: Lloyd’s Register
Published: 4 September, 2026

Continue Reading

Alternative Fuels

DNV: Alternative-fuelled vessel orders hit highest monthly level since October 2024

LNG-fuelled vessels accounted for the vast majority of August activity while the strong summer performance marked a significant acceleration in ordering activity after a relatively slow start to the year.

Admin

Published

on

By

DNV: Alternative-fuelled vessel orders hit highest monthly level since October 2024

Latest data from classification society DNV’s Alternative Fuels Insight (AFI) platform alternative-fuelled vessel ordering was strong in August, with 52 new vessels added to the platform.

This is the highest monthly total since October 2024 and follows another active month in July, when 47 vessels were added to the database.

LNG-fuelled vessels accounted for the vast majority of August activity, with 46 orders recorded. The container segment led the way with 30 orders, while the car carrier segment contributed a further 12 LNG-fuelled vessels. In addition, four ethanol-fuelled bulk carriers and two hydrogen-powered bulk carriers were added during the month, as well as one LNG bunker vessel.

The strong summer performance marked a significant acceleration in ordering activity after a relatively slow start to the year. In total, 242 alternative-fuelled vessel orders have been placed in the first eight months of 2026, representing a 27% increase compared with the same period in 2025.

LNG remains the dominant fuel choice, accounting for 63% of all alternative-fuelled vessel orders registered so far this year. Container vessels represent the largest share of these LNG orders (59%), followed by car carriers (30%).

Jason Stefanatos, Global Decarbonization Director at DNV Maritime, said: “The past two months have been particularly strong for alternative-fuelled vessel ordering, with August recording the highest monthly total we’ve seen since October 2024. This has helped lift year-to-date orders to a level well above the same period last year.

“LNG remains the leading fuel choice, driven largely by activity in the container and car carrier segments. These sectors have been among the earliest adopters of alternative fuels, supported by predictable liner operations and increasing demand from cargo owners to reduce emissions across supply chains. 

“For many owners, LNG offers a combination of emissions reductions, fuel availability and future flexibility while the longer-term fuel landscape continues to evolve. 

“At the same time, the latest figures include orders for ethanol- and hydrogen-fuelled vessels, highlighting that owners continue to explore a range of decarbonization pathways. Different segments are making different fuel choices, but the overall level of activity demonstrates continued investment in lower-emission shipping.”

Screenshot 2026 09 04 at 12.29.26 PM Screenshot 2026 09 04 at 12.29.36 PM

 

Photo credit: DNV
Published: 4 September, 2026

Continue Reading
Advertisement

OUR INDUSTRY PARTNERS



Trending