Thermography on bio-gas plants – a special project
18.05.2010
“Tasks need solutions” is the philosophy of the engineers office and analytical laboratory M. Uphoff e.K. in Aschau, Germany (www.uphoff.org). True to this motto, the laboratory has found the solution for the project “Determination of undesired thermal loss in bio-gas plants”.
The task
The measurement object is a bio-gas plant with several buildings and gas silos, which often reach heights of 20 m. Thermography is to be used to show bio-gas plant operators where heat loss is occurring, or where there are gas leaks. Since the gas is manufactured from biological products, a heat spectrum occurs which is easily represented using thermography. Heat loss from pipelines and transfer points also play an important part, and can be clearly differentiated using thermography.
In order to create uniform biological processes, and thus hinder vertical and horizontal layering, a process-dependent heat transfer must t ake place, e. g. from the heated reactor walls to the fermentation substrate. The main task of an optimized biological process is heat transfer by adjusted mixer settings. In addition to this, heat bridges to floor slabs and to the water table layers must be taken into account. Heat radiation loss from the gas hoods and gas sacks is also very significant for the stabilization and efficiency of gas production. The fermentation processes of the input substrate can be monitored for uniform heat distribution, and thus for the success of the fermentation.
The solution
The thermal imager testo 881 used on bio-gas plants and pipelines shows up any leakages or heat losses clearly and optically for the user.
With a thermal resolution of < 50 mK, the testo 881 delivers high definition images which emphasize and visualize even the smallest temperature differences.
In addition to the infrared recording, the testo 881 creates a parallel real image of the measurement site with the integrated digital camera. The optical colour alarm in the thermal image of the testo 881 makes areas of critical temperature on the bio-gas plant measurement object immediately recognizable (isotherm function).
The thermal imagers from Testo with integrated digital camera automatically store an infrared and a real image simultaneously. With the professional image overlay Testo TwinPix, these two images can be superimposed over each other in the PC software “IRSoft”. The information from the thermal image and the real image are then displayed together in one image.
A further advantage is the flexibility provided by exchangeable lenses. A standard and a telephoto lens allow adaptation to the different sizes and distances of measurement objects.
The operation of the thermal imager testo 881 and the corresponding software presented no problems for the German laboratory. The instrument could be put ot use without personal product training, based on the instruction manual and a short telephone instruction session with a Testo employee.
