PECM Issue 62 2023 | Page 38

Turning back time on marine fluid degradation

EDITOR ’ S CHOICE HEAT TRANSFER SYSTEMS

GLOBAL HEAT TRANSFER
Turning back time on marine fluid degradation
When a customer in the marine industry realised that they had not been effectively monitoring their heat transfer system and fluid they contacted thermal fluid experts Global Heat Transfer , for support . After sampling the fluid and determining the extent of degradation , experts at Global Heat Transfer worked with the customer to find the most effective solution . Reducing the carbon levels in the system was not a simple task , but the final results provided the customer with a reliable and efficient heat transfer system .
BACKGROUND
Thermal fluids can be used for a diverse range of applications in the marine industry , from maintaining the temperature of heavy fuel oils and heating liquid cargo to providing a variety of heating services in the engine room and accommodation areas . The customer contacted Global Heat Transfer , to take a sample of its thermal fluid from a large tanker .
Heat transfer fluids operate at high temperatures for long periods of time , and naturally degrade over time . If engineers do not regularly test the thermal fluid and get the specialist support and advice needed , they will not understand its condition . Degradation , caused by oxidation , causes sludge which is a thickening of the fluid which will block system pipes . To better understand its condition the marine customer sent a representative sample of the vessel ’ s thermal fluid for analysis .
UNREADABLE CARBON LEVELS
The initial analysis of the thermal oil sample was very concerning because the carbon percentage weight level was so high it was unreadable . Before this point , the previous highest recorded level for over 30 years was eight per cent weight of the fluid . It is important to note that one per cent weight of the fluid is the typical action point for changing out a fluid .
Due to the severe level of degradation , the lab couldn ’ t perform any of the eleven tests normally used to determine oil condition . As a result , fluid experts determined that the pumps , drains and strainers in the system were blocked with carbon debris . The system was covered with irremovable hard baked carbon fouling , which acts as an insulator , reducing heat transfer efficiency and causing hot spots on coils . The high levels of acidity in the system , caused by oxidation , was corrosive to the internal components of the system and drastically increased the risk of leaks and health and safety risks as pipe corroded .
If fluid condition continues to deteriorate and the system is not regularly maintained , the fluid can increase the risk of fire . Under the Dangerous Substances & Explosive Atmospheres Regulations ( DSEAR ) and the Explosive Atmosphere Directive ( ATEX ) regulations and health and safety laws , businesses must take steps to protect
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