Predictive Emission Monitoring System: Innovation in Measurement Technology

Per State of Qatar environmental regulations, Continuous Emission Monitoring Systems (CEMS) are required to be installed on combustion units with a heat input capacity of greater than 25 megawatts (MW). CEMS are well regulated in US and European jurisdictions to monitor air emissions compliance. However, CEMS entail extensive calibration requirements and are difficult to maintain and operate in the harsh climate of the Arabian Gulf. Based on the challenges noted above, Qatargas Operating Company Limited (Qatargas) and TOTAL E&P Qatar (TOTAL) collaborated on a study to assess the viability of Predictive Emissions Monitoring Systems (PEMS) as a reliable and sustainable emissions monitoring technique. The first part of the study focused on the development of PEMS algorithms and comprised a blind benchmarking evaluation of the three main types of PEMS technologies (first principles, statistical and neural networks) using data collected from an operating Qatargas gas turbine. The second part of the study assessed the operational, maintenance and cost aspects of PEMS installation with reference to international guidelines. This paper summarizes results of the first part of the above study which includes the results of the technical, blind benchmarking comparison of PEMS technologies on the pilot gas turbines. These results suggest that PEMS measurements can be as accurate as that of CEMS. One of the advantages of PEMS, being a software based-solution, is the reduced requirement for installation of additional physical monitoring instrumentation, which translates into substantially lower capital and operational costs as well as reduced calibration and maintenance requirements. The findings of the second part of the study with regard to installation and operation of PEMS installations will be discussed in a future paper. PEMS have been successfully regulated in several worldwide jurisdictions, including by the USEPA. This paper aims to demonstrate that PEMS can be a viable emission monitoring tool as both an alternative and complementary capacity to CEMS.