Compositions for controlling phytoplankton contamination
A composition for mitigating, inhibiting, ameliorating and/or eliminating phytoplankton growth in a waterbody, the composition comprising an active ingredient at concentration of 80.0-99.5% (w/w) of the composition and a coating material at concentration of 0.5-20% (w/w) of the composition; wherein the critical surface tension of the composition is between 15-60 dyn/cm and wherein the relative density of the composition, prior to being submerged in water, is above 1 g/cm 3 .
1. A composition for mitigating, inhibiting, and/or eliminating phytoplankton growth in a waterbody, the composition comprising granules comprising
an algicide at a concentration of 80.0-99.5% (w/w) of the composition, wherein the algicide comprises an agent selected from the group consisting of hydrogen peroxide, sodium percarbonate and calcium hypochlorite; and
a hydrophobic water insoluble coating material at a concentration of 0.5-20% (w/w) of the composition, wherein the coating material is selected from a saturated or unsaturated fatty acid, a triglyceride or any combination thereof;
wherein the critical surface tension of the composition is between 15-60 dyn/cm, the melting temperature of the composition is 50-90° C. and an acid value of the composition is 3-8 mg KOH per gram and wherein the relative density of the composition, prior to being submerged in water, is above 1.0 g/cm 3 such that the composition initially sinks after being applied, and wherein the composition becomes floating 0.25-60 minutes after being submerged in water, thereby causing a surfacing of the composition to mitigate, inhibit and/or eliminate phytoplankton growth in the waterbody.
2. The composition according to claim 1 , being formulated such that the algicide is released into the water at water temperatures below 45° C. within 24 hours of being applied.
3. The composition according to claim 1 , being formulated as granules with a granule size in the range of 100-1500 μm.
4. The composition according to claim 1 , being formulated as granules with a granule size in the range of 1-10 mm.
5. The composition according to claim 1 , wherein the granules have a viscosity of 6-8 cP at 70° C.
6. The composition according to claim 1 , wherein the composition comprises granules with different concentrations of coating material.
7. The composition of claim 6 , wherein the granules comprise granules having 0.5-2.5% w/w coating material mixed together with granules having 3-10% coating material, leading to slow/extended release of the algicide, and/or an extended period of exposure of the cyanobacteria to the algicide.
8. The composition according to claim 1 , wherein the composition is configured to stay submerged at a depth of about 0.02-1 m below the surface of the water system after having been applied and/or after having resurfaced.
9. The composition according to claim 1 , wherein the coating material has a partition coefficient (log P) of 1.5 or above.
10. The composition according to claim 1 , wherein the composition has a critical surface tension of between 20-45 dyn/cm.
11. The composition according to claim 10 , wherein the composition has a critical surface tension of between 28-35 dyn/cm.