CEMEX Deutschland AG is one of the biggest producers of ready-mixed-concrete, cement and minerals. In Germany CEMEX employs a staff of approximately 3,200 people and is part of the International CEMEX Group with a head count of 50,000. After the German re-unification the Company acquired the existing cement plant in Ruedersdorf.
Investments to save
CEMEX invested 300 Mio. Euros in plant modernisation and environmental protection. Dust emissions were reduced by 90%. By use of secondary fuel and raw materials a couple of thousand tonnes of resources could were saved annually.
Sophisticated control solution
After a test run of the MECONTROL Air flow measurement system CEMEX ordered PROMECONs correlation technology based flowmeter systems to measure the tertiary air flow and exhaust gas flow for each of the two production lines. Initially the tertiary air measurements have been verified with reference flowmeters which have been temporarily installed to proof the accuracy.
Tertiary air flow measurement
The tertiary air flowmeters are used to control the flow of the hot air with temperatures between 900°C and 1100°C to the preheater/ precalciner. The calciner furnace consumes 60% of the entire thermal input to the plant. The air to fuel ratio must be controlled for a complete combustion with low emissions. Furthermore a minimum flow rate must be maintained to avoid sedimentation of ash, hot meal and clinker dust in the elbow of the tertiary air duct. For this purpose the flowmeters need to be accurate and reliable. The MECONTROL Air flowmeters meet these criteria and need virtually no maintenance.
Exhaust gas measurements
The exhaust gas measurement is used to measure and control the load of the kiln plant and with this the feeding of the raw mill. By correlation of the flow rate and the fan speed of the heat exchanger material built up can be indicated and removed to keep the efficiency on a high level.
Due to extended investments for the Ruedersdorf cement plant CEMEX made the plant more economical, increased the throughput and drastically improved the environmental aspect. PROMECON supplied drift free and low maintenance flowmeter solutions to deliver substantial process information in order to improve thermal plant efficiency by maintaining full plant availability.