| 摘要 |
Continuous thermal separation and recovery of tolylene diisocyanate from liquid residues obtained during tolylene diisocyanate preparation, present in a mechanically produced fluidized-bed, comprises stirring a bed of fine-grained solid residue using a stirrer in a fluidized-bed tank, where a peripheral speed at the top of the stirrer, has a constant Froude number of greater than 1, and the bed of fine-grained solid residue introduced into the fluidized-bed tank, is present in an amount of at least 20-not > 80 vol.% of the volume available in the fluidized-bed tank. Continuous thermal separation and recovery of tolylene diisocyanate from liquid residues obtained during tolylene diisocyanate preparation, which are present in a mechanically produced fluidized-bed, comprises stirring a bed of fine-grained solid residue using a stirrer in a fluidized-bed tank made of the fine-grained solid residue, where (a) a peripheral speed at the top of the stirrer, has a constant Froude number of greater than 1, (b) the bed of fine-grained solid residue introduced into the fluidized-bed tank, is present in an amount of at least 20-not > 80 vol.% of the volume available in the fluidized-bed tank, (c) a liquid residue is heated to evaporation temperature by directly contacting with the preheated fine-grained solid residue provided in the container and the fluidized-bed, with a heat transfer coefficient of at least 120 W/m 2>K, and (d) a reverse mixing ratio of the mass of the feed stream of the liquid residues and the mass of the bed available in the fluidized-bed tank, is at least 0.2. |
