Overview
Biogas production and CHP generation in biogas power plant
Fermentation and CHP process
Biogas plants face special challenges. This also applies to the measuring instruments, which have to withstand corrosion and build-up. Directly after the digester the biogas is wet and can vary in composition; this limits the use of several flow measuring principles. As a consequence, only cleaned biogas is measured currently, in many cases. This makes any in-process evaluation difficult.
Electromagnetic flowmeters in the OPTIFLUX series can operate with solids contents in the flow of up to 70 % are very useful for measuring the supply of liquid substrate. These devices have proven themselves a hundred times over in biogas plants. OPTITEMP industrial thermometers and non-contact OPTIWAVE radar level meters ensure optimal conditions are maintained in the digester. The OPTIWAVE horn antennae are designed to measure the level of agitated media such as bio-sludge and they are insensitive to condensation. The Krohne OPTIBAR 5060 C pressure transmitters are well suited for applications in Biogas plants. With their ceramic measuring cell and interface to the process they are robust, reliable and corrosion resistant. The OPTISONIC 7300 Biogas ultrasonic flowmeter is particularly suited for the measurement of raw biogas. In addition to volume flow it can also determine the methane content – without the need for additional measuring devices. It can cope with varying gas compositions and provides no obstruction to the flow stream, so measures without any loss of pressure. The electronics enable it to efficiently process the ultrasound signals that traverse the pipe, which are highly damped by the CO2 and water content of the gas. On top of that, titanium sensor faces make the OPTISONIC 7300 Biogas flowmeter resistant to the corrosion often caused by hydrogen sulphide (H2S). OPTIFLUX and OPTISONIC heat meters are used for measurement of the quantity of heat produced by the CHP system. If this heat is delivered to third parties, we can also offer custody-transfer heat meters.