CO-LaN Management Board has authorized today the public release of the specification document for the Flowsheet Monitoring interface. This specification has been developed by the Methods & Tools Special Interest Group over a number of years. It belongs to version 1.1 of the CAPE-OPEN standard.

Flowsheet Monitoring gives the ability to extract various pieces of information from a process and to analyze them. Values of Parameters displayed by any Unit Operation, contents of streams, material, energy or information ones, can be obtained by a Flowsheet Monitoring Component, leading, as needed, to additional calculations within that specialized Process Modelling Component. Flowsheet Monitoring imposes an extended support of CAPE-OPEN within any Process Modelling Environment: for example all Unit Operations within a Flowsheet, even those from the library contained in the PME, have to be wrapped as CAPE-OPEN Unit Operations.

The need for such an interface specification was expressed at the CAPE-OPEN Annual Meeting held in Heidelberg, Germany, back in 2007. There, researchers from University of Trieste explained how they developed a CAPE-OPEN Unit Operation implementing the WAR algorithm to assess the environmental impact of a process. They had to draw numerous information streams in order to collect the information needed by the WAR algorithm throughout the process.

Bill BARRETT and Jasper van BATEN have then proposed a first version of the Flowsheet Monitoring interface specification in their paper BARRETT, W. M. AND J. van Baten. Evaluating Process Sustainability Using Flowsheet Monitoring. Chemical Engineering & Technology. Wiley-VCH Verlag GmbH & Co., Weinheim, Germany, 35(8):1405-1411, (2012). Their proposal was implemented in the WAR algorithm developed by US E.P.A. as well as in COFE (AmsterCHEM) which served as demonstrators.

This publication led in 2012 the Methods & Tools Special Interest Group to develop a first version of the interface specification document which has been revised, improved over the years till version 1.58 as released today.

Major steps were involved including a new event notification strategy which was developed in 2015 as well as a new interface ICapeStream (see the report given at the CAPE-OPEN 2015 Annual Meeting). The year after, at the CAPE-OPEN 2016 Annual Meeting, the Methods & Tools Special Interest Group reported on progress with respect to Use Cases which are a major part of the interface description relying on UML. At the CAPE-OPEN 2017 Annual Meeting, it was expected to complete a peer review of the document by the end of 2017. Other commitments by this Special Interest Group and the need to polish further the document postponed the review till the end of 2018.

As per the commitment made by the Methods & Tools Special Interest Group at the CAPE-OPEN 2018 Annual Meeting, a request for comments was issued on November 7, 2018 and received a few comments which have been evaluated and answered. The Methods & Tools Special interest Group thanks the reviewers for their work.

CO-LaN hopes that many software vendors will take the opportunity offered by this new interface specification. At first only the textual interface specification is made available. The next step will be to include its rendering in the CAPE-OPEN IDL and in the CAPE-OPEN Type Libraries and Primary Interop Assemblies.