Improving the heat and mass transfer equipment by integrating an adaptive radiant heat supply system

Abstract

This work investigates heat supply processes in heat and mass exchange equipment for implementing preliminary thermal treatment, concentration, and drying of organic plant raw materials. The task addressed is to reduce the operational complexity, energy and metal consumption in heat and mass exchange equipment with a multi-link thermal system based on intermediate heat carriers. The proposed concept integrates a radiant heat supply system based on a film-like resistive electric heater of the radiant type directly into the heat transfer surfaces. Based on the results from comparing technical and technological indicators, it was established that for a sectional cassette-capacitor apparatus, the usable heat exchange surface increased to 1.47 m2, the specific metal capacity was reduced to 330 kg/m2. For a vacuum evaporator, the usable heat exchange surface increased from 3.70 m2 to 4.15 m2 while specific heat consumption increased by 18.5%. For a rotary film evaporator, specific metal capacity was reduced from 80 kg/m2 to 57.3 kg/m2 and specific heat consumption by 1.9%. For a single-drum roller dryer, specific metal capacity was reduced to 47.0 kg/m2 and specific heat consumption by 10.7%. Integration of the adaptive system contributes to an increase in the usable heat exchange surface of devices under conditions of a decrease in the specific metal capacity and specific heat consumption with a simultaneous decrease in the number of functional links of the basic thermal system to 2…3. The resulting effect is attributed to the integration of the heat source into the heat transfer surfaces while abandoning the component of intermediate heat carriers; a distinctive feature of the concept is the universality of the application of a single approach to improving heat and mass exchange equipment. Practical significance implies implementing the concept to modernize existing and to design new resource-saving heat and mass exchange equipment