David Graham
Uniper
- Conference: Emissions Monitoring Conference
- Presentation: Quality assurance issues associated with continuous emissions monitoring of gaseous pollutants at low concentration levels
- Presentation Time: Day1 09:55
David Graham is a Technical Consultant with Uniper, working at their Technology Centre near Nottingham, England. He provides support to the UK power industry in relation to continuous emissions monitoring, emissions reporting and compliance issues for all plant types. This includes the development of guidance for reporting under the Emissions Trading System. Before joining Uniper, he was a gas turbine combustion engineer with Alstom for six years and, prior to that, he worked on various aspects of combustion and environmental science with British Gas. He is a past chair of the UK Source Testing Association and the VGB Technical Group: Emissions Monitoring. David is a Fellow of the Institution of Chemical Engineers and an Associate Member of the Institute of Environmental Management & Assessment.
In Europe, the quality assurance of Continuous Emissions Monitoring Systems (CEMS) is largely governed by EN 14181 which was first published in 2004 and revised in 2014. CEMS are referred to as Automated Measuring Systems (AMS) and there are three Quality Assurance Levels: QAL1 (Certification); QAL2 (Calibration) and QAL3 (Control). QAL1 requires that the AMS is type-approved, with a suitably low certification range, and that it is acceptable for the given process application. QAL2 requires that the AMS is calibrated by a third-party accredited test laboratory using a defined Standard Reference Method (SRM); a linear calibration relationship is established between the AMS output and the SRM test readings. The calibration relationship is checked annually, by the test laboratory, by means of an Annual Surveillance Test (AST). QAL3 requires regular zero and span checks to be performed by the operator in order to check that the drift of the AMS over time is not excessive, i.e., the AMS remains under control. As Emission Limit Values (ELVs) are lowered under the Industrial Emissions Directive, and the associated Best Available Techniques Reference documents (BREFs) for each process industry, there can be issues with every component of the quality assurance process which is based upon evaluation at the daily ELV. This presentation will review each element of the QA process and highlight issues associated with low concentration measurement whilst reviewing both existing and potential solutions