Fuel treatment systems at DanFish

08 Sep 2011

DanFish Stand D722: Gehus Consult will be presenting the MAHLE Industrial Filtration fuel treatment system at DanFish.

“Diesel Oil Pest” – a serial problem

Diesel fuel tanks can become contaminated with microorganisms during transport and storage in bunker- and day-tanks, mainly caused by tank-ventilation and condensation.

Microorganisms can only survive, grow and multiply in the water phase of any medium. Microbiological contamination can have very serious consequences: The by-products of microorganic metabolism block filter elements and diesel pipes, additionally they cause abrasion processes on injectors, especially in conjunction with free water. The material of the tank walls and pipes can also be severely damaged. Corrosion is further accelerated by water-soluble salts and hydrogen sulphide, a by-product of metabolism.

Fuel treatment for prevention

Water concentration is the crucial factor for microorganism growth and the diesel oil pest problem can only be addressed by reducing the amount of water in the fuel. This can be achieved by implementing continuous fuel treatment to prevent the water content from rising above 50mg/l (ppm). Mechanical separators which use centrifugal separation cannot provide the necessary level of dewatering. None of the systems which comply with the applicable DIN standards or the delivery standards of the mineral oil industry and NATO offer complete security, as they allow water content of 500mg/l or 200mg/kg respectively. A truly effective and lasting method of protecting fuel against increasing water concentrations, and thus against contamination by microorganisms, is to employ MAHLE fuel and oil treatment systems.

Single and multiple-stage

MAHLE fuel treatment systems can be used for all types of middle distillates, e.g. diesel fuel, marine diesel oil (MDO), marine gas oil (MGO) and others. To treat the first phase, the company offers a number of combined filter coalescers with varying degrees of fineness; these systems can be optimally adapted to meet specific requirements and technical configurations. An optional downstream separator membrane can be used to reduce the water content down to 20ppm unbound water in order to prevent growth of microorganisms, which begins at 70ppm. To treat heavy contamination with solids the company recommends using a dual-phase version of the filter coalescer; this version has an upstream filter that can be exchanged independently.

Configuration and design

MAHLE Industriefiltration supplies fuel and oil treatment systems with a wide range of flow capacities. The systems consist of a pump with a downstream depth filter or filter coalescer and an optional permanent separator, as well as a central control box, full differential pressure monitoring system and an automatic water outlet system. The systems can be supplied in vertical or horizontal configurations. They can be installed either between storage- and bunker tank for indirect treatment of the medium or directly in front of the engine.