Statistical Analysis and Adjustment of the Mass/Energy Balances of Processes

Abstract

<p>An improved technique for data adjustment to satisfy mass/energy balances for single or multiple processing unit systems has been developed. The method was successfully tested on examples from the literature. With this technique, biased data can be detected and sources of error identified and isolated.</p> <p>A multivariate normal distribution for the measurement vector x, was assumed and used to derive a test function vector w, with univariate normal distribution. A chi-square test on w is proposed for detecting biased data. An algorithm for identifying and isolating sources of bias was developed, using standard normal two-sided tests on each element of vector w and using the imbalance of the constraints, e.</p> <p>In the absence of bias, adjusted values of the measurement vector and/or the estimates of missing variables can be obtained. When chemical reactions take place, the extents of the independent reactions are also estimated.</p> <p>The main requirements of this technique are the knowledge of the process constraints and measurement statistics.</p> <p>Implementation of the technique is straightforward and it is suggested that the method be used as a diagnostic aid in process analysis.</p>