Waste Water Treatment in the Cloud [App Story]

About Krüger

Krüger A/S provides with its STAR Utility Solution online control solutions that continuously optimize and stabilize the operation of the entire system for water and waste water. STAR enables customers to reduce operational costs and costs related to adding capacity to the plant and to improve the quality of the treated water. STAR calculates real-time the optimal setpoints for pumps, gates, chemical dosing etc. based on real-time measurements.

Cloud Infrastructure

Prosys developed for Krüger A/S a scalable, cloud-based solution for the data integration needs in their STAR Utility Solution platform. In the STAR platform, measurements are taken from the water processes and calculated setpoints are fed back to them. For these data serving needs they provided a cloud-based solution running on the Amazon Web Services platform: a dockerized OPC UA server hosted behind Amazon Elastic Load Balancer.

OPC UA is a widely used framework for modeling and transferring data in various industrial processes and plants. Lately it has been advocated for an Internet of Things protocol by Oracle and many others. It has also been proposed as the communication protocol of choice for the Reference Architecture Model for Industrie 4.0.

Dockerized OPC UA Java Server

In the Krüger case, the OPC UA server serves the latest setpoint values for each plant the customer owns. The plant’s OPC UA clients write their latest measurement values to this OPC UA server for the plant to which they have access. After this, the cloud based analysis is run on the latest measurements and new setpoints are provided for the OPC UA clients to read. All data is kept safe in the cloud database, which the OPC UA server accesses. The OPC UA server Address Space also has the data available for the customer for browsing purposes.

The dockerized OPC UA server instances are run behind Amazon Elastic Load Balancer, which generates as many instances as needed based on the load of the system. Thus the costs for running the OPC UA servers are directly dependent on the number of customers and plants. Thanks to the Amazon Elastic Load Balancer, capacity is automatically allocated, as needed, without any extra effort on Krüger’s part.

Security in the Cloud

OPC UA connections are secured with built-in encryption. All applications are also authenticated using X.509 certificates, according to the OPC UA specification. For this solution, Prosys provided a customized certificate management platform, which enables easy administration of the application certificates and ensures that only the trusted applications have access to critical data.

All in all, the solution provides an automatically scalable, 24/7 online system for transferring the critical setpoint values and process measurements between the STAR Utility Platform and Krüger customer plants, all using asymmetrically secured connections.

Our dealings with Prosys have been very prompt and professional. The provided solution met all our requirements and any problems were solved in a timely manner.
Lars-Chresten Ekebjærg, Krüger A/S