Alken Even-Flo® has several effects on fuel oil storage, distribution and combustion which ultimately result on lowered operating cost. In this context, we include labor cost as part of operating cost.
Direct benefits are those that are readily and easily apparent from visual observation: prevention of organic precipitation or sludge; dispersion of (existing) organic sediment; clean tanks, pipelines, strainers, preheaters, and oil; reduction of surface tensions; steadiness of flame and unrestricted liquid flow.
Indirect benefits are the ones resulting from, and directly related to, the first benefits. While some of these results may be small, they nevertheless add up to savings in fuel, increased heat, higher efficiency, and less maintenance: burners free of carbon; a steadier flame; less or no smoke; less and drier soot; better heat transfer through the flues; reduced stack temperatures; increased carbon dioxide; and less oil consumption.
To Schmidt's list of benefits from a good treatment, we would add that the ability to operate with less excess air provided by Alken Even-Flo® results in lowered sulfur trioxide in the flue gas (SO3 is the prime cause of "cold-end corrosion" in air heaters, etc.) and lowered formation of vanadium pentoxide in the furnace (V2O5 is the prime cause of slag).
Most of the above benefits can be seen by simple observation, over time, by operating personnel, or by simple stack gas tests. Of course, determination of actual boiler efficiency with and without the use of Alken Even-Flo® (a complex task) would also prove the point.
Ultimately, the benefits of Alken Even-Flo® are measured by the reduction in fuel and maintenance costs with Alken Even-Flo® against those costs, under identical conditions (or for the same amount of production or steam generated) without Alken Even-Flo®.