| abstract |
The invention relates to a method and device for obtaining nitrogenous fertilisers from organic waste products in liquid phase (suspension, emulsion, solution), for the sanitation of the wastes and for emission reduction by thermal treatment using mineral or organic adjuncts. According to the invention, the above is achieved by means of a method in which the waste product is heated to a temperature of between 40 ~C and 90 ~C at a reduced pressure, the gas emitted, which contains carbon dioxide and ammonia, is cooled and introduced into an aqueous absorption agent, the nitrogenous fertiliser thus produced is removed and the excess unabsorbed gas containing carbon dioxide is pumped back into the waste chamber, whereby the vacuum generated at the beginning of the process by a vacuum pump is self-maintaining. The recycling of the excess gas into the circuit is advantageously achieved either directly above the waste product for treatment, or via a gas cooling system directly above the waste product for treatment, or in divided form, with a part stream through the waste product and a part stream above the waste product. A gypsum slurry is preferably used as aqueous absorption agent. |