Tanker Loading – OFF SPEC Cargo

A 99K DWT tanker vessel was presented for inspection upon completion of its first foot loading of a cargo of gasoline.

Joint sampling conducted by Shippers and charterers surveyors, and subsequent testing, showed the cargo loaded to be off specs. The parameter that failed testing was the Flash point of the Gasoil The loading terminal FOTT thereafter cast of the vessel and asked her to shift to anchorage with this part cargo. The vessel shifted to anchorage, pursuant to which the vessels owners IG P&I club requested us to attend.

WHAT WE DID
We initially boarded the vessel at anchorage and sampled all the loaded tanks
We attended the lab for testing of these samples together with other interests.
At that time, we discovered, post testing that Gasoil in all the nominated tanks 1P, 1S, 4P, 4S, Slop P, Slop S was Off Specification as the minimum flash point requirement was 60 degree Celsius.
We thereafter requested sampling and testing of the shore tank from where the nominated cargo originated.
Together with the charterer’s representative, we sampled the shore tank
The shore tank sample was jointly tested for flash point, and it was observed passed, with the flash point very close to the minimum required - 61°C vs minimum required 60°C
This presented a piacular problem for the owners, since the supplier cargo was in specs…

We then conducted, together with the owners, a theoretical calculation for volumetric dilution of flash point.
The theoretical calculations resulted in cargo being in specs, and the owners, in their eagerness to continue the loading asked the vessel to re-tender NOR for further loading.
We remained cautious of these theoretical calculations, and urged the owners through the P&I club, as a safety net, to have a blend sample prepared between the first foot sample (4.16% by volume) with the shore tan sample (95.84% by volume) and have it laboratory tested.
Indeed, this sample failed the minimum flash point requirement (result 58.5°C vs minimum required 60°C)
We thereafter started our investigation into a cause consideration. Given that the vessel would NOT achieve the required flash point for the cargo when fully loaded, a decision was taken to discharge the full parcel of the first foot cargo at VOPAK terminal. This discharge was achieved without incident.

The vessel thereafter re-arrived the FOTT terminal, and was presented for loading after the initial first foot Off-spec cargo was transferred to Tank # Slop P and was discharged at Vopak Terminal, Fujairah.
The vessel thereafter was lined up to load and loaded three (3) parcels of Gas Oil in a comingled condition as equally distributed by volume in all her nominated tanks. The cargo was loaded from 2 separate terminals.

We continuously attended the vessel during the loading operation, and as pre agreed internally drew the following samples during the loading progress
• Manifold samples at the time of commencement of loading
• First foot samples from each cargo tanks # 1P/S, 4P/S & Slop P/S
• Composite cargo tank samples after completion of 40% of cargo by volume
• Composite cargo tank samples after completion of 80% of cargo by volume
• Composite cargo tank samples after completion of loading of nominated quantity

The above samples were tested, and each resulted in flash point being barely above the minimum required 60°C, with the 4(P)-sample testing only 59°C.
We again became suspicious and in order to ascertain the reason behind this low flash point readings post testing, we insisted on sampling the cargo from the Port facility distribution line.
We found out that DL No. 5 and DL No. 7 were being used to feed the vessel its cargo the second time. Both DL samples were tested, and indeed, DL 5 sample resulted with reading of 51.5°C and DL 7 with 60°C
We immediately alerted the Port Terminal Manager of this, and after an operational discussion we had, it was decided that further loading would continue only with DL 7 line.
We thereafter met the shipper’s representative and had a dialogue with him, and ultimately convinced him to isolate the DL5 from the Matrix manifold.

The Port facility thereafter carried out line pushing for DL 5, pursuant to which we again tested the sample from DL5, and results obtained were 61.5°C
The loading thereafter continued till completion, with the final parcel sampled upon completion was tested to find the cargo fully in specs.

OUR VALUE ADDITION
We ensured what is commonly know as good practice – Had we relied solely on the results of the theoretical calculation of volumetric dilution, and not insisted to corroborate the results by a lab test of a bled sample by volume, it was certain that during the initial loading, the vessel would have ended up with a full load cargo being off spec – the monitory consequences thus in comparison with discharge of fist foot cargo versus full cargo would have been disastrous.
We did not sit back as mute observers assuming all would go well during the second loading. We continued to sample, test and monitor, and consequently were able to identify the issues related to off spec cargo within DL 5, quickly, and prevent further issues.
We took tangible action to protect our customers interests – not only did we identify the DL 5 issue during the second loading, but we also liaised with operation owners (terminal and supplier) insure prevention of further loss by convincing them to isolate DL 5 from the matrix manifold

We also investigated the initial issues with contamination, and found a likely leaking manifold cross over valve, the possibility of vapor phase contamination, in view that vessel was initially also loaded with MOGAS in the remaining tanks.

About the Authors:
Capt. Vispy Rusi Dadimaster

A career spanning 22+ years in various operation and management positions within the Maritime and Shipping Industry, including 8+ years in Fujairah (Port Operation, Agency and Logistic Management), and in command of various types of vessels, including Offshore Dynamic Positioning crafts. Within the professional roles held, I have proven to be result oriented, decisive, possess tremendous interpersonal skills, and am technically oriented My entrepreneurship skills have enabled me to lead and managed teams up to 25 people successfully, achieving challenging objectives, within challenging environments, with an aim to create a positive outcome and impact.