Algae bloom removal

Algae1.jpgBlue-green algae or cyanobacteria are gram-negative bacteria that obtain their energy through photosynthesis. They have a huge resistance to adverse conditions due to their simple construction. Typically, they occur in lakes, ponds and slow-moving streams but they can survive even in hostile environment due to their simple construction.

Massive development of cyanobacteria is caused by the accumulation of nutrients in stagnant water (eutrophication). Algae Blooms can cause human allergic reactions manifesting by skin irritation. They also pose a risk due to the production of dangerous toxins responsible for vomiting, headache and liver problems.

On the basis of a study by doc. RNDr. B. Maršálek, Ph.D. (Masaryk University in Brno, Faculty of Science) and Prof. RNDr. R. Zbořil, Ph.D. (Palacký University in Olomouc, Faculty of Science), nanoparticles of elemental iron were proved for environmentally friendly cyanobacteria elimination.

Blue-green algae removal by ENVIFER (potassium ferrate) seems to be even more promising. The product was tested by the team of scientists mentioned above and showed the ability to eliminate cyanobacteria as well as the nutrients needed for their growth (e.g. phosphates and nitrates). At the same time, the product exhibit low toxicity towards water organisms, such as Daphnia magna and fish.

4 modes of action:

  1. Prevention mode - removal of bioavailable phosphorus.
  2. Destructive mode - cell destruction.
  3. Immobilization mode - ability to immobilize microcystin on the large and positively charged surface of the non-toxic and environmentally benign ferric hydroxide.
  4. Physical mode - formation of a highly flocculated waste product consisting of destroyed biomass and Fe(OH)3.

Iron based sustainable greener technologies to treat cyanobacteria and microcystin-LR in water

Iron based technologies using magnetic zero-valent iron nanoparticles (nZVI) and ferrate ion (FeVIO42-, Fe(VI)) represent greener approaches to remove cyanobacteria and degrade MC- LR in water. This paper reveals that nanoparticles of zero valent iron (nZVI) can destroy cyanobacteria in the source water and may play a preventive role in terms of the formation of cyanobacterial water blooms by removing nutrients like phosphate. Results on MC-LR showed that Fe(VI) was highly effective in removing MC-LR in water.

Simultaneous removal of algae and its odorous metabolite dimethyl trisulfide in water by potassium ferrate

Co-removal of oscillatoria algae and its potential odorous metabolite dimethyl trisulfide (DMTS) in simulated algae-laden alkaline source water by potassium ferrate (K2FeO4) was investigated in contrast to potassium permanganate (KMnO4) pre-oxidation followed by polyferric chloride (PFC) under varying conditions, including pH, initial oxidant dosage and turbidity. Potassium ferrate resulted in 92.4% removal of algae, higher than PFC when the dosage was equivalent as measured by Fe and KMnO4 showed obviously positive effect as a coagulation aid. Degradation of dimethyl trisufide (92.5%) by potassium ferrate was better than the pre-oxidation of potassium permanganate (74.6%), and the treatment time was decreased from 10 min to 1 min.