Eventos Anais de eventos
ENCIT 2022
19th Brazilian Congress of Thermal Sciences and Engineering
Analysis of energy loss through the thermal insulation of a digester
Submission Author:
Wendel Malessa , RS
Co-Authors:
Wendel Malessa, Paulo Roberto Wander
Presenter: Wendel Malessa
doi://10.26678/ABCM.ENCIT2022.CIT22-0350
Abstract
The industrial market is demanding more sustainable production and more energy efficient plants. This work is inserted in this context, using thermodynamics and heat transfer as fundamental bases for the determination of energy loss in the form of heat through thermal insulation in glass wool, which is installed in a digester for continuous cooking of eucalyptus wood for cellulose extraction. This cooking is a process that demands a large consumption of steam, which today is generated through the burning of coal and black liquor, and its conscious use is important to achieve the company's sustainability goals. Through the analysis of data obtained in the supervisory control of the process and field visits using a thermographic camera, a great heat loss was observed through the walls of the digester, revealing a high degradation of the original insulation. Applying mass and energy balance of the control volume, it was possible to determine the amount of energy lost to the surroundings and convert it into steam flow to verify its cost for the process. By doing a heat transfer analysis using the thermal resistances concept, it was possible to assess the state of the current insulation and estimate the possible gains with a new insulation. The results obtained showed that the installation of rock wool with a thickness of 50 mm results in savings of 99% of the current steam cost and the cost of this installation has a payback time of less than 6 months of plant operation. These results reinforce the importance of carrying out periodic checks of the real state of insulating surfaces and carrying out renovations when necessary.
Keywords
Thermal Insulation, Sustainability., Thermal Energy, Thermodynamic Efficiency., Energy balance
