Views: 53 Author: SEPPE Publish Time: 2021-01-05 Origin: SEPPE Technologies
1. Glass powder method
The glass powder method uses the prepared glass powder containing SO3 and other gases to pass through the flame with 1100-1500 ℃. At this time, SO3 and other gases overflow from the glass powder due to the decrease of solubility and the change of furnace environment atmosphere. At the same time, the glass powder becomes spherical due to the surface tension at high temperature, and the overflow gas is sealed in spherical particles to form a cenosphere.
2. Spray granulation method
The spray granulation method is first made of sodium silicate solution containing auxiliary special reagent (boric acid, urea and five ammonium borate). Then, the solution is sprayed into the spray dryer through the nozzle. After dripping, the powder is obtained with a certain particle size. Finally, the powder particles are heated and foamed to form Cenosphere.
3M company from the United States was the first to use this process to produce cenosphere. Because of the shortcomings in chemical stability and homogeneity of the products, people have studied to add metal oxides with low melting point, high viscosity and high surface tension to improve the performance of cenosphere.
3. Drop method
The droplet method is basically the same raw material as spray granulation. The raw material is water glass, adding the same amount of 10% five ammonium borate aqueous solution. After mixing evenly, spray into the spray drying tower and form Cenosphere after drying.
4. Drying gel method
The alkoxide is mixed according to the required proportion and then added into dilute hydrochloric acid to decompose with water. After gelation, drying at 60 degrees and 150 degrees at different stages, then grinding and classifying with ball mill, the dried gel powder was obtained and then foaming in a vertical 1280 degree electric furnace to produce Cenosphere.