The development of aCurve: a rich internet application for process analysis at Käppala WWTP

In modern wastewater treatment plants (WWTPs) the demand for advanced process control is a prerequisite for a smooth and energy efficient operation of the plant. Most large WWTPs have distributed control systems (DCS) and advanced supervisory control and data acquisition systems installed for operation and supervision of the plant. Normally the DCS is sufficient for the operators to run the plant efficiently. However, data is also often wanted by others than the operators (e.g. research engineers, students, scientists or consultants) for analysis and reporting or to perform different calculations. At Käppala a new web based program, aCurve, has been developed to meet such needs. The program is a so-called Rich Internet Application and is accessible via internet and requires no desktop installation. The main features of the program are rapid presentation of graphs, easy zoom, changing resolution, performing calculations and plotting the results and simple statistics (e.g. mean values, integration, maximum and minimum values). If advanced calculations are acquired, the data is easily exported as an xlsx-file for use in Microsoft Excel or other software capable of reading the Office Open XML SpreadsheetML File format. aCurve can also produce automatically updated reports that are built in Microsoft Excel. This makes the reporting function flexible and any user with Excel knowledge can create and edit a report with a professional result. The reports can easily be shared throughout the organization. The program has replaced other expensive and complex desktop application that were previously used at the Käppala WWTP. Process and laboratory data that can be used for follow up of plant performance has now become available for a greater part of the staff which improve the quality assurance of reported data to authorities and researchers.