In the Netherlands, Evodos acquired its 35th customer for its algae production system, and cited four factors in its rapid scale-up. 1. High quality of the harvested algae. 2. Almost double (~ 90%) the cultivation yield. 3. Customers experience a reduction in drying, storage and transportation costs of that figure as well. 4. Energy requirement of 0.1 kWh per kg dry weight compares to a 1.5% energy balance, for dewatering.
1. High quality of the harvested algae
Both from customers but also from scientific institutes we get reports on the cleanness of the Evodos algae cake. Reports quote that the volume of extracellular water in the cake is a few percents only. Apart from considerable consequences for downstream processes, a major issue is the minimal quantity of non wanted products in the cake like salt, bacteria etc. Some customers even consider to refrain from washing the dewatered cake. Not having to wash the cake results in major savings in up- and downstream processing.
2. Upstream cost effect up to 90%
A demo at a Dunaliella Salina production plant showed that Evodos may almost double (~ 90%) the cultivation yield. At this strain, Evodos harvests 95% of these algae in one piece compared to presently accepted losses of ~ 30% of valuable β-carotene. The harvested algae cake contains minimal extra-cellular water so no further washing is needed. The present technology demands washing where another 30% is lost. Multiplying the efficiency of both steps shows that about 50% of the expensive product is lost. The > 95% efficiency of one step Evodos processing allows production over 90% more product at the same cultivation cost, combined with major savings on down-stream processing.
3. Downstream cost effect up to 49%
Evodos totally dewaters the algae. These is simply no free water left. In the case of Nannochloropsis our customers measure dry weight percentages of 30%. Present technology dewaters up to 18%. The major impact of this is that the harvested Evodos product contains 49% less water. Our customers experience a reduction in drying, storage and transportation costs of that figure as well.
4. Energy balance of 1.5% is possible
We already knew that the energy balance of harvesting algae with Evodos is positive, but we were very surprised when we received feedback from the field by A/Prof David Lewis, University of Adelaide, Australia:
” We are extremely pleased and impressed with the performance of the EVODOS Type 10, which we use to concentrate Tetraselmis spp. from 6 to 30% solids (w/w), which requires 0.1 kWh per kg dry weight! This is right on track to return a positive energy ratio in regard to producing and processing microalgae biomass for biofuel feedstocks. We look forward to incorporating the Type 25 and Type 250 into our process soon…”
The energy requirement of 0.1 kWh per kg dry weight compares to a 1.5% energy balance. From a dewatering perspective we are on the road toward biofuels.
More background on the story from the Digest