摘要 |
<p>A method for recovering phosphorus from organic sludge includes the steps of producing incinerated ash from organic sludge, mixing the incinerated ash with a carbon source, vaporizing phosphorus from phosphorus compounds in the incinerated ash by heating the incinerated ash mixed with the carbon source in a non-oxidizing atmosphere, preferably, at 1,000 to 1,250 DEG C, and recovering phosphorus by bringing the vaporized phosphorus into contact with water to condense the vaporized phosphorus. Alternatively, the vaporized phosphorus is oxidized to phosphorus pentoxide, and phosphorus is recovered as phosphoric acid by bringing the phosphorus pentoxide into contact with water. Instead of the steps of producing incinerated ash from organic sludge and mixing a carbon source with the incinerated ash, by dehydrating and drying organic sludge and carbonizing organic substances in the organic sludge, preferably, at 400 to 700 DEG C, similar effects can be obtained. <IMAGE></p> |