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SEM Char Investigation
and Further ECOSS Analysis
Here is a scanning electron microsope image (SEM) of the 400C char. (Acknowledgements to Jason Nadler for his fine work) This picture is taken at 70x. As you can see in the bottom right hand corner, the physical structure of the cellulose material is apparent. The char particles are a hard carbon with more strength the higher temperature chars, but grinds easily. These particles are hydrophobic in nature and differ from char made at high temperatures.
The next image is taken at 350x and provides more detail of the char's surface. The image reflects some of the biomass origin as the physical structure had been broken up by the mechanical actions of pelletizing.
Its surface shows evidence of the cellulose layers. The internal gases that escape from the material during the charring, help develop charcoals natural porosity. But at this level of magnification, the pore structure is not visible.
This image is taken at 3270x clearly show pore structures. The evolution of this adsorbent material provides a porous internal structure as well. The melted look could not be seen from the char by eye and varies from higher temperature chars. We interpreted the images as a sign of the microscopic deposition of compounds which microbes might use as a food source.
The question of whether we could create a fertilizer external as well as internal was one we could only answer by trying. So our preliminary design was prepared. While the patent pending process can apply to many configurations, the development of a simple production technique was important.
In this case we used a mechanical fluidized bed easily adaptable to any gas stream and injected CO2, and water vapor with ammonia. The char was feed in at regular intervals varying from 15-30mins. The longer durations produced significantly larger particles. The image on the left is the initial char. Carbonized structures from the shell material are visible in the center of the left panel picture. The image in the center is a material produced after 15 minutes and the one one the left after 30 minutes.