CHAPTER No.10

STORAGE PROCEDURES

Routine Checks:

To ensure that product quality is satisfactory maintained whilst in storage, the following procedures must be applied:

Visual check shall be carried out after receipts and setting until tank is water free, water check may then be reduced to weekly if past experience shows more frequent checking is unnecessary. Water checks must be made prior to release and daily when deliveries continue.
The correct operation of floating suction arms shall be checked weekly. The correct positioning of swing arm suctions shall be checked each day that deliveries are made.
When tanks are consistently replenished via dedicated (*) transport and fully segregated (**) systems, no laboratory testing of product on receipt is necessary. However, as a check on contamination during transportation or while in storage, the tank contents must be subjected to a periodic test on an average sample at fixed intervals of six months for all grades of aviation fuels tanks are not required to be quarantined during this procedure (***).
Static stock shall be sampled after six months for periodic test (average sample) and thereafter, every three months.
If the results of test (c) and (d) are unsatisfactory, the tanks mast be quarantined and an Average Sample taken from each tank for full Specification Test which must prove satisfactory before the stock can be released.

(*) Dedicated Transport: A transport means containing exclusively the concerned product and having contained it during the previous journey.

(**) Segregated System: Such a system that the pipeline and equipment used are exclusively reserved for the product concerned and that there is no connection except blanked off – with pipelines ore equipment containing other grades.

(***) Periodic Test: May be omitted b mutual agreement if it is not a requirement of any of the participants.

Tank Cleaning:

Tanks shall be cleaned one year after commissioning and subsequently every three years. More frequent inspections or cleanings may however be necessary, for example, if short filter lives or poor millipore test results downstream of the tankage indicate the presence of excessive contaminants or if the condition of water drain samples (discoloured water, slime, positive sulphide tests, etc.) suggest the presence of microbiological or surfactant type contamination.
No chemicals or cleaning materials shall be used which could contaminate the aviation products to be stored in those tanks. Date of cleaning should be stenciled on the tank shell and a record maintained, giving brief details of tank condition, contaminants found, etc.
After filling, a rectification test shall be carried out on an average sample which must be satisfactory before the tank contents may be released.
A detailed record of the types and quantity of sediments found and of the condition of the tank interior fittings and coatings should be maintained.

Change of Grade in Storage Tanks:

After any change of grades has been made, the operating company should conform to their own decontamination procedures or as agreed by the participants, and after filling with the new grade of product a recertification test shall be carried out on an average sample which must be satisfactory before the tank contents may be released.

Where product change is from a leaded to unleaded grade, or for any other non-aviation grade, additional safety and quality protective measures are necessary and advice should be obtained from appropriate sources.

Storage Tanks:

The storage tanks are all of steal construction with butt-welded welded shell’s and lap-welded bottoms and roofs. For most purposes vertical tanks are preferred in our constructed in capacities upto one lakh cubic meters. Horizontal tanks are also used, specially when tanks have to be buried and vary in capacity from 50 – 260 m³.

It is necessary to maintain a slight pressure in the vapour space of the tank to reduce evaporation losses or alternatively, to eliminate the vapour space by the use of a floating roof or plastic blanket.