Evaluation of the application of Predictive Emissions Monitoring Systems (PEMS) in Europe taking into account the boundary conditions of the standards EN 14181 and EN 15267
Predictive Emissions Monitoring Systems (PEMS) are software-based data acquisition systems for continuously monitoring emissions by means of plant process data. A PEMS is interfaced with the plant process control system. It utilizes inputs from the combustion or pollution control process to determine the emission rates of various pollutants that are regulated. The predictive emissions monitoring system does not need any gas analyzers.
By employing historic paired emissions and selected process data (e.g. load, fuel composition, flow, pressure and temperature data, environmental conditions, turbine and boiler settings or variables of the flue gas abatement system) a model is generated, which allows determining the actual plant emissions for compliance purposes. PEMS may be used as an alternative to C(ontinuous) E(missions) M(onitoring) S(ystems) for all gas or oil-fired plants (turbines, boilers, heaters etc.) for components like NOx, SO2, CO, O2, CO2, but also for NH3, H2S, HC, VOC.
These so-called empirical PEMS (in contrast to parametric PEMS) have been tested and evaluated with positive results within the frame of corre-sponding programs by the US Environmental Protection Agency (US EPA) in the last decade. Special emphasis has been put on quality assurance of the results. PEMS can be applied in lieu of CEMS according to title 40 C(ode) (of) F(ederal) R(egulations) Part 60 (especially Performance Specification 16) and 40 CFR Part 75 (Subpart E). PEMS is used at multiple plant sites, particularly in the US, but also in the Middle East. In Europe PEMS so far is not common and applied basically in the Netherlands.
A strong motivation to replace CEMS with PEMS results from cost savings due to lower capital expenditures as well as much lower operational and maintenance cost. This motivation is based on the expectation that PEMS can accomplish equal accuracy and quality of emissions data compared to CEMS.
Within this research program, it shall be investigated if results of continuous emissions monitoring with PEMS are equivalent to conventional monitoring methods. For this, a research program shall be conducted with the following priorities:
- Selection of suitable monitoring and process parameters.
- Fundamental investigation, to what extent PEMS is compliant to cur-rent European emissions regulations.
- Determination and definition of meaningful minimum requirements according EN 14181 and EN 15267 for certification/approval of PEMS.
- Comparison CEMS - PEMS for an extended period at two plants.
- Model suitability test at two plants, basically in parallel.
The project will be co-financed by a group of power plant operators particularly interested. The designated research institutions support the project implementation with in-kind contributions.
The project is supervised by the VGB-Technical Committee "Emissions and Immissions".
Project results will be presented in a workshop involving representatives of licensing authorities.