With the increase in fuel and operating costs, ship owners and operators try hard to maintain their profit levels. The profit of shipping companies depends on the efficiency of their operations linked to the quality of the crew and the machinery onboard. And of all machines, the ship’s main propulsion plant is of crucial importance when it comes to overall efficiency.
No machinery is 100% efficient meaning that a 100 % input or supply to run the machinery entails a less that 100% output, due to the energy loss while working, mainly in the form of heat energy, which, in turn, can be used in different types of useful applications, such as turbocharger, steam turbine generator, economizer or fresh water generator.
One specific applications is “evaporation” or using the excess heat for heating up the sludge tank. By heating up the oil water mixture, part of the water is boiled and is removed as clean vapor, creating extra storage capacity in the sludge tank.
Like a pan of water on the stove, wastewater subjected to heat is evaporated leaving the pollutants to be skimmed off or disposed of as sludge.
In short, the evaporation technique eliminates safely and naturally the water portion of a waste oil stream; leaving behind the oil content to be disposed of.
That means that sludge quantities can differ from ship to ship.