Sox Scrubber or Exhaust Gas Cleaning System (EGCS) | Seaman vlog | Chief Boyet

Summary

In this episode, Chip Boyet explains the purpose and operation of exhaust gas cleaning systems (EGCS), commonly known as scrubbers, on ships. He highlights the impact of the IMO 2020 sulfur cap regulation, which limits sulfur emissions from ship exhaust gases. The scrubber is a key solution, using either open-loop or closed-loop systems to remove sulfur oxides (SOx) from exhaust gases before they are released into the atmosphere. The video discusses the benefits, challenges, and maintenance of scrubbers, the costs involved, and how the system interacts with various types of water, ensuring compliance with environmental regulations while considering operational efficiency.

Takeaways

• 😀 Scrubbers, also known as Exhaust Gas Cleaning Systems (EGCS), help vessels meet the 2020 IMO sulfur cap regulation by reducing sulfur emissions from exhaust gases.
• 😀 The 2020 IMO sulfur cap regulation limits sulfur content in fuel to 0.5% globally, and 0.1% in Emission Control Areas (ECAs).
• 😀 There are three main ways to comply with the sulfur cap: using compliant fuel, using alternative fuels like methanol or LNG, or installing a scrubber system.
• 😀 Scrubbers come in two types: dry and wet, with wet scrubbers being more efficient in removing sulfur oxides (SOx) from exhaust gases.
• 😀 Wet scrubbers can be classified into open loop, closed loop, and hybrid systems, with open loop systems commonly used on many vessels.
• 😀 Open loop scrubbers use seawater to neutralize sulfur oxides in exhaust gases, turning them into sulfuric acid and effectively removing the pollutants before discharge.
• 😀 The seawater used in open loop scrubbers has high alkalinity, which helps neutralize the acid formed from sulfur oxides, making it safe for discharge back into the ocean.
• 😀 A key limitation of open loop scrubbers is that they can't operate in freshwater or areas where seawater alkalinity is too low, as it wouldn't neutralize the sulfuric acid effectively.
• 😀 Using scrubbers has both advantages and disadvantages; while they save on fuel costs (by using high-sulfur fuel), they require maintenance and operational effort.
• 😀 If a scrubber fails and cannot be restored quickly, the vessel must switch to compliant fuel while repairs are made. In extreme cases, if compliant fuel is unavailable, a Non-Availability Report must be submitted to authorities.

Q & A

What is a scrubber, and why is it important for ships?

A scrubber, or exhaust gas cleaning system (EGCS), is a technology used to remove harmful sulfur oxides (SOx) from exhaust gases produced by ships' engines and boilers. It helps ships comply with IMO 2020 sulfur cap regulations by reducing sulfur emissions into the atmosphere, thus minimizing the environmental impact and improving air quality.

What are the key regulations that the scrubber helps vessels comply with?

The scrubber helps ships meet the IMO 2020 sulfur cap regulation, which limits sulfur emissions in international shipping. Vessels operating outside Emission Control Areas (ECAs) must use fuel with no more than 0.5% sulfur content, while ships operating inside ECAs must use fuel with a sulfur content of 0.1% or lower.

How does a scrubber work to remove sulfur oxides from exhaust gases?

A scrubber works by spraying fine seawater or fresh water into exhaust gases, which contains sulfur oxides (SOx). The sulfur oxides react with the water, forming sulfuric acid, which is neutralized by the seawater’s natural alkalinity. The cleaned exhaust gases then exit the scrubber, meeting the required sulfur emission limits.

What are the different types of scrubbers used on ships?

There are two main types of scrubbers: dry scrubbers and wet scrubbers. Wet scrubbers are more commonly used and come in three variations: open-loop, closed-loop, and hybrid. Open-loop scrubbers use seawater, while closed-loop scrubbers use fresh water, and hybrid scrubbers can switch between both methods.

What is the difference between open-loop and closed-loop scrubbers?

Open-loop scrubbers use seawater to neutralize sulfur oxides, which is then discharged back into the sea. Closed-loop scrubbers use fresh water, and the water is treated and recirculated after use, rather than discharged into the environment. Hybrid scrubbers combine both systems and can be switched between open and closed-loop modes.

Why are open-loop scrubbers not suitable for use in all areas?

Open-loop scrubbers are not suitable in areas where seawater has low alkalinity, or where discharging acidic wash water could harm the marine environment. Additionally, some ports and countries have regulations that prohibit or restrict the use of open-loop scrubbers due to the potential environmental impact.

Can scrubbers be used in freshwater areas or rivers?

No, scrubbers cannot be used in freshwater areas or rivers because freshwater lacks the alkalinity needed to neutralize the acidic wash water. Using scrubbers in such areas could result in discharging harmful acidic water into the environment, which would damage marine life.

What happens if a scrubber malfunctions while a ship is operating?

If a scrubber malfunctions and cannot be repaired within one hour, the ship must switch to compliant fuel to continue operations. The crew, in collaboration with the ship manager and scrubber manufacturer, must find a solution to restore the scrubber or seek alternative fuel sources if necessary.

What is the advantage of using a scrubber over using compliant fuel?

The advantage of using a scrubber is cost savings. While compliant fuels are more expensive, using a scrubber allows a ship to burn high-sulfur fuel, which is significantly cheaper. For example, using a scrubber could save up to $200-$300 per metric ton of fuel, which can add up to considerable savings for the vessel owner over time.

What should a ship do if compliant fuel is not available in a port?

If compliant fuel is not available in a port, the vessel must submit a 'Fuel Oil Non-Availability Report' (FONAR) to the authorities. This document informs them that the required compliant fuel is unavailable, and the ship is permitted to use the available fuel while taking appropriate actions to resolve the situation.