DIESEL FUELS & DIESEL FUEL SYSTEMS

Application and Installation GuideDiesel Fuels & Diesel Fuel Systems• Coalescing filter systems workeffectively to removesediment and water. If thelevel in the day tank is notmaintained at a consistentlevel, install them betweenthe main tank and the daytank. If proper day tank levelsare maintained, a smallersystem can be used betweenthe main tank and the daytank to clean only the fuelbeing burned. These filterscan plug and careful attentionmust be given to fuel pressurelevels at the injectors to guardagainst misfiring.• A centrifuge system can beused, particularly if the fuelquality consistently fallsbelow the defined limitsdiscussed in this guide.CentrifugesThe centrifuge represents the mostexpensive and complex method ofwater separation, but it is the mosteffective. It is used extensively inmarine, offshore and powergeneration applications where acontinuous power supply isessential, and the continuous supplyof clean fuel cannot be left tochance. A typical distillate fuelcentrifuge schematic is shown inFigure 9.A centrifuge manufacturer shouldbe consulted to determine the propercentrifuge type, size and flowrequirements for a specificapplication.While Figure 9 shows a singlecentrifuge schematic, manyapplications will require the use oftwo (2) centrifuges, with one of thecentrifuges acting as a standby.The required flow rate of acentrifuge can be approximated asfollows:P x b x 24 x 1.15Q =R x tWhere:Q= Flow required, L/hrP= Total Engine Output, kWb= Fuel Consumption, g/kW-hrR= Density of fuel, kg/m3T= Daily separating time inautomatic operation: 23 hrOr:Q =f x be x 24 x 1.15R x tWhere:Q= Flow required, gal/hrP= Total engine output, bhpBe= Specific fuel consumption,lb/bhp-hrR= Density of fuel, lb/galT= Daily separating time inautomatic operation: 23 hrNote the following considerationsfor configuring a centrifuge.• The centrifuge manufacturershould assist in the finalcentrifuge selection.• The centrifuge flow has beenincreased by 15% as a safetyfactor for operationaltolerances.©2005 Caterpillar®All rights reserved. Page 27