Relative Accuracy Test Audit Evaluation for Flue Gas Continuous Emission Monitoring Systems in Power Plant

Continuous emissions monitoring systems (CEMS) permanently installed for selected processes require initial and periodic quality assurance audit tests to ensure that they are functioning properly and reporting emissions accurately. Depending on the industry and process type, there are several sets of regulations that dictate the exact QA/QC requirements that the CEMS must meet. Measurement data by CEMS is a legal base to charge for pollutant emission. But the great masses of CEMS have some problems of high data drift and low measurement accuracy etc. For evaluating CEMS Relative Accuracy, we simultaneously compared SO₂/NOx and dust monitoring systems with CEMS and normal handmade sampling method at different boiler load. It draws a conclusion that relative accuracy test audit (RATA) of SO₂/NOx monitoring systems goes beyond criterion. The data should be corrected. Continuous opacity monitoring systems is exact. CEMS should carry out RATA and bias test to ensure measurement data validation and accuracy.