Assessment of efficiency of transformation of heat in the processes rectification of braga
To assess whether the use of vapor recompression in distilling plants, mathematical modeling and optimization modes vessels with transformers warmth. The aim of this work is to evaluate the feasibility of using vapor recompression processes rectification of braga and optimize energy economic parameters of heat pump installations. The distillation column can be operated at different pressures, the temperature difference between the boiling liquid in a bottom part of the column and the vapor leaving the top part is from 1 - 2 (in the final column purification) 10 - 25 (in use, distillation columns). A small temperature difference allows obtain high values of the heating rate, while the high intensity of the processes of heat transfer in condensation and boiling provides a relatively small heat exchange surface in the respective heat exchangers and capital investments in them. These circumstances require high economic efficiency of application of heat pump installations. After analyzing the data, concluded that for option 1 (work rectification columns under vacuum) to an optimum mode of operation corresponds to the saturation temperature of the compressed vapor 98, the pressure of the alcohol vapor compressor after this will be P2=191 kPa. For option 2 (work of the distillation column at low vacuum) optimum temperature value t2=107 C, the pressure of the compressed steam P2=244 kPa. For option 3 (work of the distillation column at the small of excessive pressure) it is economically feasible t2=110 C, P2=265 kPa. The optimal-temperature pressure in the boiler for the considered variants respectively co-tute of 5.4; 5,3 5,3; the increased pressure of the compressor is accordingly to 3.67; 2,98; to 2.57.