Siemens Exploring Use of Magnets to Harvest Algae
27 November 2009
Siemens has demonstrated in the lab a new magnetic method to harvest algae for use as feedstock in biogas plants.
The researchers put magnetite particles in the water with the algae. The algae enclose these iron oxide particles, which are only a few micrometers in size. The resulting mixture of algae and magnetite can then be extracted using a magnet without having to drain the water— a major cost and time factor in other harvesting schemes.
The new technology offers numerous advantages, Siemens says, including less water loss and more efficient cultivation. The amount of algae harvested can be determined by varying the amount of magnetite used. A certain amount of algae is left behind as the starting stock for the next population.
So far the new technology has only been used on the laboratory scale, but the Siemens researchers are confident that it will also work on a larger scale. The next step would be the construction of a pilot plant for conducting further tests of the scalability and efficiency of the method.
Crude oil sometimes has metal in it, so it is only logical to put metal into algae.
Most people do not have any idea of how little efficient algae is at converting sunlight to fuel or what the cost of growing and processing the algae is. The high production rates quoted in the literature have never been demonstrated on a large scale and if they ever are, the cost of the fuel cannot compete with the cost of getting crude oil out of the ground.
When you drive a car on biofuel, you must remember that there is a person in the world that could have used the ethanol or bio oil to eat to keep warmer or more.
The plants proposed for cellulostic ethanol can be fed to animals to produce milk and so can the ethanol itself. ..HG..
Posted by: Henry Gibson | 29 November 2009 at 04:29 PM