Investigation of an optimization method for time constants to calibrate reaction calorimeters

Abstract

In exothermic reactions, scale-up sometimes endangers the chemical process because of the risk of runaway reactions. Reaction calorimeters are used in a laboratory to design a safe chemical process by collecting thermal and kinetic parameters for scale-up. Because scale-up can magnify the errors obtained in laboratory experiments, the cooling capacity can be improperly calculated based on the underestimated heat generation due to thermal lag. Therefore, reaction calorimeters are required to provide accurate heat flow despite thermal delays inherent in the reaction calorimeters.This study validates the time-constant search method for a reaction calorimeter that employs a function of smoothness S(τ) in the presence of noise. The degree of noise was determined by measuring the actual value using a reaction calorimeter. The simulation conducted using spreadsheets demonstrated that even in the presence of noise, it is possible to achieve high accuracy in the search for time-constants when there is a small thermal lag and a large intensity of calibration heat. Moreover, the use of a third-order polynomial approximation to calculate the derivative value proved to be suitable for determining the time constant accurately.