ALTERNATE FUEL BLENDING SYSTEM AND ASSOCIATED METHOD

A fuel control system for controlling the use of primary fuel and alternate fuel in an internal combustion engine without cross-contamination of fuel types. Cross-contamination of fuel types may eliminate the ability to receive certain benefits or financial incentives associated with use of alternate fuel, including but not limited to RINs, credits, and subsidies. In one embodiment, primary and/or alternate fuel are controllably delivered from sources to a flow cell. If blending is desired, both primary and alternate fuels are delivered to the flow cell. The engine is fed with the resulting primary fuel, alternate fuel, or blended mixture of fuel from the flow cell. The flow cell contains a bypass inlet port adapted to receive excess fuel not consumed by the engine in lieu of the excess fuel being returned to the primary and/or alternate fuel sources. In this manner, cross-contamination of the fuel sources can be avoided.