Bunker Quality: In-Line Viscosity
Monitoring Vs Sampling - page 2
Understanding why the viscosity of blends can vary from load to load is only one piece of the puzzle. Understanding what happens as a result of varying viscosity is another. Varying grades of bunkers form layers when stored in the same storage tank. As a result, in order to maintain a viscosity set point, fuel oil combustion control systems are required to react to drastic changes of bunker viscosity when an interface between varying bunkers meets the fuel oil pump suction. (See the graph below to view an example of varying loads of IF0120). The graph illustrates a considerable change of viscosity between layers of IF0120 referred to in the graph as Loads °A" and °B". The change in viscosity required a reduction of fuel temperature from 240° F to 200° F in order to maintain the Viscosity Set Point of 30 cSt. Consider what would happen if the operator relied solely on a theoretical Temperature Set Point derived from typical Fuel Combustion Curves. Burner tips would foul more frequently and emissions would be adversely affected.
Cambridge Viscosity, Inc. (CVI), a leader in providing solutions for viscosity monitoring and control, has developed a solution to real-time monitoring of marine bunkers. CVI has been providing Heavy Fuel Oil Viscosity Control and Bunker Blending Viscosity Control systems since its formation in 1984. Cambridge has since released a bunker-monitoring version of the VISCOpro 2000 that utilizes an in-line sensor and microprocessor technology to provide real-time viscosity data during bunkering operations. The Cambridge VISCOpro 2000 bunker monitor is endorsed by J.J. Sietas KG Schiffswerft shipyard of Hamburg for all new-builds that require a bunker monitoring system. "With the rising cost and declining quality of fuel oil, smart buyers are now demanding more and more quality verification. The bunker monitor can assure every litre in every ton delivered", says Ernst Thone, Energy Consultant of Martechnic GmbH.