About 10 years back, when the price of diesel was high and people were running diesel cars on fryer oil, people would use a motor driven or jet driven centrifuge to clean the fryer oil. Names i remember are wvo designs or simple centrifuge. In the case of the jet driven CF, people would feed it i think with junkyard power steering pumps.
Are you trying to remove water, particles, or both? If just particles, I think adapting an on engine oil centrifuge is going to be the only way you'll come close to that price.
Otherwise, the smallest industrial centrifuges, Alfa Laval MAB103 for example, start around $12,000. A filter array can do everything s centrifuge can. The initial cost will be lower with a filter but the operating costs will be higher. If you're not processing a large volume of dirty fuel, your operating cost will not likely offset the initial cost.
Centrifuges typically don't work on a wide range of viscosities. If dealing with viscous fuels such as bunker (an obsolete fuel which is no longer available to purchase) you must use a heater to control viscosity.
