Plant measurements, lab analyses and various types of data are not 100% error free. Using “raw” measurement without correction (by operators check or by computer mathematical programs) to generate plant and units balances usually yields incoherencies in the balances. Mass balance reconciliation programs (M.B.R.P) calculates detailed mass balance of units/plants using specific mathematical programs and all available redundancy. Determined single set of reconciled values represents the most likely status of actual plant operation during the accounted period of time. Results are consistent with mass, energy and properties conservation laws as well as it respect the defined constraints of units.We will look inside the various items included into a processus of M.B.R program in term of identification, representation, measurement, error’s propagation, logic of balancing algorithm, results files, indicators, reports and communication aspects. Items to be examined are :1) Representation of process plant and instrumentation (M.B.R. model) in term of graph by using process flow-sheet, by checking of instrumentation and location of sampling point, etc.
2) Analysis of availability of redundant, of missing, non identifiable or “calculable” measurements or data.
3) Selection and definition of standard and specifics reports, spread-sheet, tables, graphics.
4) Management of application (data transfert from/to external systems, storing and writing results, etc.) that handles different aspects of accounting production.
5) Processing by M.B.R program means as :analysis, fiftering and replacing of “fault” raw data, statistical tests for detection, identification and correction of data, run of reconciling program, output filing and results and indicators of quality of raw data, reconciliation run and final values.
6) Human check of data, results and indicators and final approval of “official” results.