Algal biomass, efficiently collected is valuable: because of the abundance
of diatoms, a refinable oil product is likely.

Depending upon the season, the algal turf biomass resulting from ATS must be harvested every 5-15 days to maintain high levels of productivity. Algal Turf Scrubbers® are more productive than terrestrial crops, mean yearly rates in the central U.S. being 30-50g (dry)/m2/day. Traditional crop production in the U.S. is 2-4 grams dry weight/m2/day. Switchgrass can be higher than corn and soy, and in the central U.S. is 3-6g/m2/day. Algal turfs have no recalcitrant fibers and lignin; they are more easily refined than corn and soy. At the same levels of light, they can photosynthesize and produce new tissue at roughly 10-20 times that of typical crops.

Ethanol, butanol, and biodiesel production have all been demonstrated at bench scale from ATS biomass.

Dense algal turf cover of many species, mostly green algae and diatoms, on a STA cleaning a stream in central Florida.
ATS: Biofuel Potential
1 acre of average river cleaning ATS using the new 3-D substrates that enhance diatom retention produces 180 kg of dry biomass/day (yearly mean)

Volatile solids average 40 - 50%, and such ATS units can produce ethanol at 6X the rate of corn and biodiesel at 12X the rate of soy bean based on average US agricultural production.
Early vacuum harvester on a tertiary treatment ATS. New designs are lighter and more mobile, like a lawn mower.
+ click to enlarge     

Whole systems approach