Emission Monitoring - Development of Predictive Emission Monitoring
Emission monitoring plays a key role in the trend towards lower emissions. Regulators want to ensure that the set emission limits are followed and need a means of monitoring the performance of the installations. Emission control technology, such as SCR, use emission measurements in order to tune the process to the correct operating point. In addition, recordkeeping and reporting of emissions e.g. in annual reports is a means of providing visibility and importance to emissions. Exhaust gas from diesel engines has proven challenging for emission monitoring systems. Even systems developed for use in harsh conditions, such as in coal fired power plants, often do not perform adequately when measuring from diesel engines operating on heavy fuel oil. Cold-dry systems where the exhaust is cooled down to remove moisture and acidic components typically require frequent attention in long term continuous operation. In-situ systems as well as hot-wet extractive systems require less maintenance, but are typically more costly. This article will discuss experience from emission monitoring equipment installed after diesel engines. Predictive emission monitoring is an alternative to traditional analyzer based emission monitoring which can provide both cost efficient and robust monitoring. Instead of directly monitoring the emissions in the exhaust gas from the process, PEMS monitors process parameters and can based on the state of the process provide estimates of the emissions. There are both first principle models and empirical models for calculating emissions from a combustion process. First principle models are well aimed at understanding the underlying physics in the process and for understanding how process changes will influence the emissions. Empirical models utilize recorded process data to generate a model of the emission performance of the process. W(a)rtsil(a) has performed field tests of an empirical PEMS as a replacement for analyzer based solutions on a W(a)rtsil(a) 38 engine. Evaluation of paired emission and process data together with the field test results for NOx modelling are encouraging and highlight PEMS as a powerful tool for emission monitoring. Being cost efficient, PEMS also opens up the possibility for emission monitoring in applications where analyzer based systems are not feasible.
Jan Torrkulla Markus Loevholm
W(a)rtsil(a),Finland
国际会议
上海
英文
1-12
2013-05-13（万方平台首次上网日期，不代表论文的发表时间）