Quantifying Sludge Volumes in Oil Storage Tanks

The Argus Group offers a unique, patented system for determining the volume of oil sludge in a tank, which replaces the inaccurate manual dipping method.

This technology has been well proven within refineries throughout the world and results have been validated by the customer on a regular basis.


The system can accurately locate, map and quantify the levels of sludge in floating roof crude oil tanks while they are still in service.

The Sludge Profiler for Oil Tanks (SPOT) has been designed to accurately locate and quantify sludge build up in the bottom of floating roof crude oil storage tanks.  The system is based on sonar and during a 360° sweep 240,000 soundings are used to assess the sludge build up.

The scanning is executed without shutting down the storage tank.

The sonar head is linked to a computerized station where a constant read out is available. This provides continuously updated three-dimensional grid plots of the profile of the sludge in the bottom of the tank an accurate sludge volume (within +/-5%).


The location and quantification of the sludge build up is conducted with a full tank, which allows to avoid problems connected with working in a very narrow space with a low roof.

Given a high volume of sludge on the bottom of the tank, the lowering of the floating roof of the tank comes together with the risk of damage. This risk is significantly decreased whiule using the SPOT system. Furthermore, the system can also constantly correct the schedule of the stirring rod.

The system is intrinsically safe, as it is a totally sealed vessel that is completely nitrogen filled.  The system has an automatic power shut down mechanism where if the pressure should drop the power to the system is cut off.

The SPOT system has full BASEEFA/ATEX certification.