What is a marine scrubber?
Marine scrubbers, also called Exhaust Gas Cleaning systems (ESGS), are used to remove any harmful parts of exhaust gas in marine engines – such as sulphur oxides (SOx) and nitrogen oxides (NOx). This is becoming more and more important, since the marine industry has an increasing focus on making shipping greener and more sustainable.
How Senmatic’s sensors can ensure stable operation
Within the process of removing harmful elements from the exhaust gas, Senmatic’s marine approved temperature sensors are used by many shipping lines, to measure the temperature of the water, which is entering or exiting the scrubber. By measuring the temperature through high-quality marine approved sensors, it is ensured that the scrubber operation runs as efficiently and correctly as possible.
Why scrubbers have been developed
Scrubbers have been developed to minimize the pollution caused by exhaust from marine engines. The pollution is harmful to both humans living near ports and the environment itself. The marine industry has seen a great development in green initiatives, due to the fact that global shipping is one of the most polluting industries.
“A marine scrubber is relatively easy to install, cost effective and an environmentally friendly solution to reduce the pollution emission from ship engines.”
Keld Reimer Hansen Key Account Manager at Senmatic
The 2020 sulphur oxide regulation
On January 1st, 2020, a new regulation from the International Maritime Organization (IMO) comes into power, when it comes to the amount of sulphur emission from ship exhausts globally. The restricted limit being put into action in 2020 will be 0.5 percent on a global scale.
“These new regulations by the IMO means that vessel owners have to make a decision whether to install a scrubber on their vessels or to employ one of the other solutions such as installing new machinery, which can run on low-sulphur fuel. This dates back from the restriction that was introduced on January 1st 2012. Back in 2012, the global sulphur fuel limit was set to 3.5 percent. “
Keld Reimer Hansen
Key Account Manager at Senmatic
Options to achieve the 2020 sulphur oxide regulation
- Install a marine scrubber
- Use a low sulphur residual marine fuel e.g. (LNG) liquefied natural gas (if the current machinery can work with it)
- Convert existing machinery that can run on a low sulphur fuel – also called Retro Fit
- Install a new machinery that can run on a low sulphur fuel solution.
“These new regulations by the IMO means that vessel owners have to make a decision whether to install a scrubber on their vessels or to employ one of the other solutions such as installing new machinery, which can run on low-sulphur fuel. This dates back from the restriction that was introduced on January 1st 2012. Back in 2012, the global sulphur fuel limit was set to 3.5 percent.“
Keld Reimer Hansen Key Account Manager at Senmatic
The different types of marine scrubbers
There are different types of marine scrubbers, including Open loop scrubbers, Closed loop scrubber, wet scrubbers and hybrid scrubbers (open loop and closed loop).
Wet scrubbers
Wet scrubbers are classified as such, because they use water in the purification process of exhaust gas, in some cases with an alkali added. As shown at the picture there are several types of wet marine scrubbers.
Open loop scrubber
The open loop marine scrubber uses the alkalinity from seawater for the scrubbing, which helps neutralise the acid. Because of this, it does not need any caustic soda or any other alkali, which closed scrubbers often need. Open loop scrubbers are often seen as the most straightforward scrubbing method.
The open loop scrubbers can be used in most seas globally, as long as the level of alkalinity is high enough.
“The open loop scrubber is often the cheapest solution, while it is also an efficient option, which makes it a very popular choice among many shipping lines such as Maersk and DFDS.”
Keld Reimer Hansen
Key Account Manager at Senmatic
Closed loop scrubber
In contrast to the open loop scrubber, the closed loop scrubber works in a continuous loop, where water is circulated inside of the scrubber.
When the exhaust gas has entered the scrubber, it is sprayed with a water solution, with added alkali such as caustic soda or magnesium oxide. The sulphur oxide becomes neutralized as the exhaust gas reacts to the water and binds like salt.
Hybrid scrubbers
Hybrid scrubbers are different from the previously mentioned wet and dry scrubbers in the way that it is a combination of the two and has the flexibility to operate in both open and closed loops. It uses seawater to remove the sulphur oxide from the exhaust of the engine. This makes it possible for the vessel to work in a great variety of waters from low alkaline water, such as in ports, to the open ocean.
Our sensor solutions meet the marine standards and classification requirements.
Senmatic’s marine sensor certifications
Senmatic has received the European Union Recognised Organisation (EU RO) Mutual Recognition Type Approval Certificate for a wide range of temperature sensors including:
- Resistance Thermometers Type-B, BF, BJ, BL, DMH, GW, NS, PMK, PTE, PTL, PTR, S and MNS
- Thermocouples Type- DMK, DML, MK and TDMH
Because of this certification, Senmatic now offers more type classification supported by 12 different Marine Classification Societies.
Senmatic sensors used for marine scrubbers
For marine scrubbers, Senmatic has 4 marine approved sensors that are often used for different scrubber solutions. Some scrubber installations need more customized solutions, where the needs cannot be met with standard temperature sensors.
Senmatic has a wide range of experience within these types of tasks with customization and can often minimize the workload and potential issues with the implementation, if involved in the process as early as possible.
If you are interested in learning more about Senmatic’s marine approved temperature sensors for scrubbers or any other marine installations, please feel free to contact us.
