Formaldehyde (FA) is an ubiquitous compound in the environment. FA is present in nearly all incomplete combustions. It is also present as a result of off-gassing from formaldehyde-containing materials such as wood products, carpets, paint, etc… FA causes local irritation, acute and chronic toxicity and has genotoxic and cytotoxic properties. It is now classified as carcinogen. The EU-directive 2010/75/EU on industrial emissions does not provide requirements for this component. Hydrogen fluoride is a highly dangerous gas, forming corrosive and penetrating hydrofluoric acid upon contact with moisture. The gas can also cause blindness by rapid destruction of the corneas. The EU-directive 2010/75/EU on industrial emissions provides a daily ELV of 1mg/Nm3.
ProCeas® LaserCEM is a realtime online gas analyzer for the continuous extractive emission monitoring of gases. ProCeas® LaserCEM consists of a combination of Low Pressure Sampling (LPS) and Optical Feedback Cavity Enhanced Absorption Spectroscopy (OFCEAS). Both methods are patented. The Low Pressure Sampling (LPS) samples gas from the stack employing a sonic nozzle inside the probe. Behind the sonic nozzle and up to the exhaust of the pump, sample gas pressure is substantially reduced. ProCeas® LaserCEM measures the gas concentrations using optical absorption spectroscopy. The light passes through an optical cavity (resonator) equipped with highly reflective mirrors. The optical path is therefore several kilometres long, allowing even the smallest gas concentrations to be reliably measured. LPS and OFCEAS provide several advantages that will be discussed.
Regarding performance, we will consider a CEM matrix with the concentrations of the main compounds in accordance with the annex B of EN 15267-3. Considering such kind of gas composition, the Limit of Detection (LoD) of Formaldehyde with the ProCeas® LaserCEM is better than 0.067mg/m3. For hydrogen fluoride, the reachable limit of detection is better than 0.009 mg/m3. We will present results of the repeatability and linearity for these 2 compounds. Also we will demonstrate that the levels of cross-interferences are very low due to the combination of the LPS and OFCEAS. And finally, the reachable lowest ranges will be discussed according to the requirements of EN15267-3 and the QAL1 certified ranges.