Installation of strain gauges directly on the stirrer
The strain gauges applied directly to the stirrer paddles will detect loads, overloads and deformations. This means the measurement technology is really "on site" and directly where the action is. This allows previously implemented calculations and simulation to be verified, and to indicate and implement constructive improvements for future plants based on the actual occurring forces. However, the ambient conditions in the fermenter pose a particular challenge for the installation of the strain gauges. The paddles, and therefore the measurement points for the strain gauges and relevant cables, are located directly in the biomass, a constantly wet and aggressive environment. This means: the measurement point and cable must be absolutely resistant against biomass and moisture.
Because of this difficult task, Axpo Kompogas decided on a complete HBK solution: Strain gauges, a measurement data aquisition system and evaluation software - together with the direct installation of the measurement technology on site by experienced HBK service technicians.
The HBK experts installed the strain gauges directly to the stirrer paddles and ensured the measurement points were professionally and permanently protected by means of a special multiple seal. In this case, they used the HBK know-how, unique worldwide, acquired during the installation of strain gauges in wind energy offshore plants, where the measurement technology needed to be installed and appropriately sealed in locations up to 30 meters under seawater.
Measuring amplifier systems SoMat eDAQlite
The "HBK SoMat eDAQlite" amplifier in use here, which is applied directly to the face of the shaft, can also display all its particular strengths. SoMat eDAQlite is not only small, it can also be used under extreme ambient conditions. The processed measured data is stored in eDAQlite and (if required) compressed, and can be read in the HBK evaluation software catman® on the PC when necessary via the Ethernet interface. The Axpo Kompogas technicians have access at all times to the measurement data with this monitoring solution.
It was important for Axpo Kompogas to have HBK as a partner for the complete measurement technology solution. With this complete solution, Axpo Kompogas was able to put an operational measurement system into operation - with minimum training requirements and perfectly designed for the hard conditions of the fermenter. HBK took over the responsibility for the entire measurement chain project and ensured scheduled completion by the time the fermenter passed acceptance.