BRITANNIA LOSS PREVENTION OCTOBER 2024 THE SURGE IN DEMAND FOR MONO ETHYLENE GLYCOL (MEG) ACROSS MULTIPLE SECTORS, SPANNING FROM AUTOMOTIVE, TEXTILE TO PHARMACEUTICALS OR COSMETICS, HAS SEEN A PROPORTIONAL RISE IN OFF-SPEC CARGO CLAIMS. It is widely used as an ingredient for production of polyethylene terephthalate (PET) resins, fibres, films or antifreeze and coolants. This article aims to highlight the importance of understanding the intricacies of MEG and some of the safety considerations for its transportation. SAFE HANDLING OF MONO ETHYLENE GLYCOL FOR REFERENCE AND AS BACKGROUND TO UNDERSTANDING THE CARGO, IT’S IMPORTANT TO KNOW THAT MEG IS A HIGH SPECIFICATION AND PARTICULARLY SENSITIVE CARGO. MEG is a chemically hydrophilic substance, meaning it can easily form hydrogen bonds with solvents such as water or alcohol, it also has a low freezing point. Typically, it is synthesised by reacting ethylene oxide with water and the product is practically colourless, odourless and sweet tasting with a syrupy appearance. Therefore, the production process poses a unique challenge due to the formation of impurities such as aldehydes (by-products), which are inherently difficult to separate from MEG. Factors like production process instability or failure in process control can contribute to the presence of aldehydes, specifically formaldehyde or acetaldehyde, in MEG. CARGO OVERVIEW 2 | BRITANNIA LOSS PREVENTION | GUIDANCE QUALITY VULNERABILITY LIKE MANY OTHER CHEMICAL CARGOES, THE QUALITY OF MEG CARGO IS SUSCEPTIBLE TO EXTERNAL FACTORS SUCH AS PRESENCE OF WATER, ULTRAVIOLET TRANSMISSION (UVT), AND CHLORIDE CONTAMINATION. Any compromise in these aspects can significantly reduce the cargo’s value, so it’s essential to take precautions to ensure safe transport. MEG cargoes may require strict exclusion of water, which in turn, requires tank cleanliness to a very high-purity standard. This protocol helps to prevent contamination by residual organic and inorganic substances within the ship’s containment system, i.e., tanks, pumps, heating equipment, and pipelines. Consequently, a wall-wash survey before loading and sampling the initial “first-foot” cargo is important. After prolonged intervals between MEG loading at the terminal, the loading arm or hoses may sometimes be exposed to inclement weather, i.e., rain or sun, etc and these lines should be flushed before loading starts. Consequently, it would be a common practice to request for manifold samples to be tested before opening up to nominated cargo tanks to ensure the cargo quality conforms to the agreed specification as per voyage instructions. The first foot sample should be tested to ensure the results are also in satisfactory condition. However, this may involve suspending the cargo operation which should be agreed amicably between all parties of interest. Furthermore, extended exposure of MEG to the air for a prolonged period during transportation tends to deteriorate the cargo quality when dissolved oxygen reacts with the cargo in a process called oxidation (by both thermal and catalytic means). During this oxidation process, MEG reacts with oxygen or other oxidising agents to produce aldehydes (e.g., glycol aldehyde, glyoxal, formaldehyde, acetaldehyde) and the corresponding acids. Therefore, it may be advisable to carry out nitrogen padding in ship’s cargo tanks after loading (particularly for long voyages). The process of nitrogen padding for cargo tanks containing MEG is common to preve