摘要 |
The plant comprises a reactor for hydrolysis under pressure and is characterised in that it comprises at least two devices for decompression and separation (6,16,18), at least one intermediate decompression and separation device (6;16) and a final decompression (18) and separation device; a heat exchanger forming an evaporator (12,14) being arranged between two successive decompression devices, comprising a heating fluid circuit and a cooling fluid circuit, the vapour produced by the decompression device upstream being introduced into the heating fluid circuit to produce an indirect heat exchange with the liquid leaving the downstream decompression device introduced into the cooling fluid circuit, the condensed vapour (CV) being conveyed in liquid phase to the said distillation column, while the vapour produced by at least one intermediate decompression (16) and/or by the final decompression (18) are employed at least partially to superconcentrate the solution and/or to perform a heat exchange with the condensates introduced into the column (8) for their distillation. According to the invention the design of the plant is simplified while the overall heat efficiency is improved. |