Remotely monitoring the energy production in biogas plants
Finsterwalder Umwelttechnik uses digitalization for process optimization
Access to the machine or plant control system during commissioning or maintenance is now standard practice – and this is also the case at Finsterwalder Umwelttechnik GmbH & Co. KG. The company from Bernau am Chiemsee designs and produces special machines for biogas plants that are used worldwide and commissioned remotely. But Finsterwalder Umwelttechnik goes one step further and uses the remote access and IOT application from MB connect line to monitor measured values during ongoing operation that allow conclusions to be drawn about the plant and process status and lay the foundation for stable waste utilization and energy generation.
At first glance, biogas plants seem like a pretty simple thing: Biowaste enters the plant and, under a large haze of moss-green PVC membrane, biogas is produced from it.
But as is so often the case, the devil is in the details. Effective, efficient and optimized biogas production from organic waste is only possible with know-how, a great deal of experience and considerable process engineering effort. Only if all machines within the biogas plant are perfectly adjusted, the process runs smoothly and the biogas production is also optimal. In order to be able to transmit plant as well as machine and process data on demand at any time, an appropriate remote access router is necessary. The industrial router mbNET in combination with the IOT extension mbEDGE, in this combination as EDGE gateway, offers the optimal basis for this implementation.
More process reliability through maximum connectivity
In mid-2019, those responsible at Finsterwalder Umwelttechnik began looking into the topic of remote access and remote maintenance. When selecting a manufacturer, Johannes Fischer, Head of Development at Finsterwalder Umwelttechnik, focused in particular on the expertise of the manufacturer and its focus on remote access solutions. Therefore, his choice fell on the established German company MB connect line. The fact that this was the right choice also became apparent in the run-up, when the best solution for Finsterwalder Umwelttechnik was worked out in the course of extensive and differentiated consulting. This direct contact to technical experts and the support are convincing arguments in favor of MB connect line. “If something comes up, we can call and get immediate, fast and competent support,” Johannes Fischer describes the cooperation with the specialists for remote access systems. Since then, every machine is delivered with an mbNET router MDH816 and optionally with the IOT extension mbEDGE.
The Corona pandemic immediately put the effectiveness of remote access to the test. But even abroad, where the network connection can be unstable and very slow, the reliability of remote access was assured at all times.
“If access to the machine and plant parameters works so smoothly, then yes, you can also use it to transmit the process data and thus continuously monitor and optimize the plant during ongoing operation,” recalls Managing Director Tobias Finsterwalder of the initial ideas for remote plant monitoring.
“By monitoring the bicarbonate content, we can significantly increase the production reliability of biogas plants and make it transparent.”
Managing Director Tobias Finsterwalder on the advantage of continuous control
More simplicity through central know-how
The fact that the machine builder also takes care of the process in the plant after commissioning is an untypical approach for special machine construction. Normally, the know-how for plant operation lies with the operator himself or with a plant manufacturer.
This case is different. Here, the complete process know-how lies with the machine builder Finsterwalder Umwelttechnik. The plants, equipped with patented machinery, are erected at a wide variety of locations by a wide variety of operators. Waste generation and waste recycling are usually located in close proximity to each other. With this decentralized arrangement of plants, an economic optimum can be achieved between transport distances and waste utilization.
In order to operate a biogas plant under optimal conditions at all times and to solve problems quickly, experts must be able to continuously monitor the plant, machine and process parameters.
More energy through continuous monitoring of the process parameters
There is one very essential parameter for the evaluation of a biogas plant: the bicarbonate content of the digested sludge. The higher this content, the lower the susceptibility of the biological process and thus of the biogas production to disturbances. A drop in the bicarbonate content can occur over several weeks. But if this is not detected, it can lead to a permanent reduction or even a failure of the biogas production.
In order to become independent of regular and costly laboratory tests and to achieve a higher data density, Finsterwalder Umwelttechnik has developed a measuring device that determines the bicarbonate content from the digested sludge. It is installed in the piping system of the biogas plant and regularly takes samples once or twice a day. This provides a high density of data on the biological state within the plant. This parameter, which is so essential for biogas production, should not only be displayed on the control panel of the plant control system, but if possible be visible to all responsible persons at any time. Thanks to the extensive functionality of mbEDGE, this data can be visualized via Node-RED and thus trends can be determined. Via remote access, a plant operator can keep himself informed about the condition of his plant from anywhere and, if necessary, initiate countermeasures.
More functionality through individual display options
“The difficulty was mainly in conceptualizing which values should be displayed and how. The subsequent programming was then no longer the problem,” Johannes Fischer summarizes the simple implementation with mbEDGE. The data exchange between the measuring device and the MB connect line router takes place via OPC UA. Thereby, the measured values are displayed in a dashboard by means of the Node-RED integrated in mbEDGE. The library with predefined functions enables the individual display both in terms of functionality and, for example, in terms of coloring and layout. In parallel, boundary conditions are defined, which trigger an alarm on the dashboard and even additionally via e-mail to the responsible persons. If a limit value is not reached or if the bicarbonate content decreases too much, the corresponding messages are displayed and the relevant departments are automatically notified. Thus, all relevant information recipients can initiate the necessary steps to implement the optimization of energy management.
“By monitoring the bicarbonate content, we can significantly increase the production reliability of biogas plants and make it transparent,” says Tobias Finsterwalder, describing the advantage of continuous monitoring.