The Technique Of Data Reconciliation And Its Application In MES

In the integrated automation system, MES (Manufacturing Execution System) is responsible for conversion, processing and transmission information of the production process control and operation and management, and is an important bridge and link between production process control and management information. So the quality of process data significantly affects the performance and profit gained from monitoring, real time optimization, control, and other application in MES. So, data reconciliation and gross error detection techniques have been widely applied in chemical plants in order to achieve balanced and correct process data.Process data reconciliation on the basis of detection and elimination of gross error,is to acquire reconciled values of measurement, which both can meet mass and energy balance of the unit equipment or plant and can make the bias between the measurement and the reconciled value minimum. At the same time it can acquire the estimated values of unmeasured parameters and diagnose the malfunction source. The main contents include gross errors detection, data reconciliation and parameter estimation. The aim is to improve the reliability, precision and consistency of process data and to provide high quality data for process industries.Many works have been done in this field and much progress has been made in the last few years. Commercial software has been developed and applied in mass balance, production planning, process control, malfunction diagnose in large-scaled chemical enterprise. But most of these theory research and software adopt traditional statistical tests and linear method and are limited in practice.This paper introduces the basic principles of data reconciliation and analyses the defect of the classical gross error detection. According on the actual process in a chemical plant, has designed a reasonable data reconciliation algorithm. A set of data-reconciliation software is made and put an on-line application in a large scale methanol plant. The reconciled data and gross error detection bring about a desired result.