Chemical and petrochemical industries store liquid raw materials and products in large flat-bottomed above ground storage tanks. These tanks especially the flat bottoms have to be tested in certain time-periods, because if leakages or heavy corroded areas are not discovered in time, holes will result with spillage of the liquid contained. The conventional testing method requires shut down, emptying the tank and an inside inspection and their result are doubtful. The results of the first integrity tests of storage tanks by the use of acoustical methods were inconsistent, mainly because of the lack of a confident data base.
The aim of the project is to develop and demonstrate an on-line integrity test for above-ground liquid storage tanks by means of acoustic emission (AE). The final result of the project will be a test procedure before and during the tests and limit of the results and for the inspection organization a complete evaluation and diagnostic data base.
After lab tests, where the specific noise of artificial defects (leakages and corrosions) will be acquired, evaluated and inserted in a data base, the results have to be validated during field tests at two different partners (tank users) on different tanks. These tanks have to include the most different service conditions and possible defects. After the AE test of the tanks, each tank has to undergo a follow-up inspection according the conventional method and the bottom will be checked with ultrasonic and/or flux leakage scanner. In parallel a commercially available AE equipment including transient wave recording, will be adapted for the field-insertion (pattern recognition, (t and cross-correlation).
Funding SchemeCSC - Cost-sharing contracts
20090 Segrate Milano
1030 BN Amsterdam