Experimental investigation of N2O formation in selective non-catalytic NOx reduction processes performed in stoker boiler

Stoker fired boiler plants are common throughout Eastern Europe. Increasingly strict emission standards will require application of secondary NOx abatement systems on such boilers. Yet operation of such systems, in addition to reducing NOx emissions, may also lead to emission of undesirable substances, for example N2O. This paper presents results of experimental tests concerning N2O formation in the selective non-catalytic NOx emission reduction process (SNCR) in a stoker boiler (WR 25 type). Obtained results lead to an unambiguous conclusion that there is a dependency between the NOx and N2O concentrations in the exhaust gas when SNCR process is carried out in a coal-fired stoker boiler. Fulfilling new emission standards in the analysed equipment will require 40–50% reduction of NOx concentration. It should be expected that in such a case the N2O emission will be approximately 55–60 mg/m3, with the NOx to N2O conversion factor of about 40%

The current place of nitrous oxide in clinical practice

Nitrous oxide (N2O) has been used for years as an essential part of general anaesthesia. During the past few decades, however, its use in general anaesthesia has steadily declined. Parallel to this evolution, we witness a growing interest in the use of N2O by nonanaesthesiologists, mainly as a sedative and adjuvant for pain therapy during procedural interventions.1–4 In line with this paradigm shift, heated debates, frequently blurred by strong emotional viewpoints, are questioning the current place of N2O during anaesthesia and during procedural sedation.5 In an attempt to search for up-to-date answers to these issues, the European Society of Anaesthesiology (ESA) convened a number of clinical experts to debate specifically on the following questions. 1. What is the place of N2O in today's perioperative anaesthesia management? 2. What is the place of N2O in procedural analgesia and sedation? 3. Is administration of N2O associated with a health risk for patients and/or providers? Members of the task force consisted of the chairs of the ESA Scientific Committee and Research Committee, and the chairs of the scientific subcommittees on Pharmacology, Paediatrics, and Monitoring, Ultrasound and Equipment. In addition, Western and Eastern European key opinion leaders on the use and place of N2O in adult and paediatric anaesthesia were asked to join the task force. The present consensus statement is the result of an intensive debate based on the available literature and the expert opinion of the task force members