CEM India 2017

CEM India - Abstract

Abstract Title: Monitoring Strategies & Solutions for Flue Gas Pollutants
Abstract Type: Oral
Presenter Name: Mr Roland Zepeck
Company/Organisation: JCT Analysentechnik GmbH
Session Choice: Continuous Emission Monitoring

Abstract Information :

The paper will cover Continuous Emission Monitoring Systems and the various analytical methodologies for online and offline gas and particulate monitoring, detection techniques, quality assurance, International approvals, as well as give an outlook towards predictive emission monitoring systems (Predictive Emission Monitoring System, emission concentration prediction/calculation without online monitoring as alternative to continuous online monitors).

Monitoring of gaseous and particulate emissions from plants through stacks and other emission discharge lines has been developed since many decades, starting from the industrialized nations in Europe. In the beginning, only manual spot measurements were done which later was followed by continuous online monitoring.

Monitoring of pollutants is always the first step to reducing pollutants:

If we don't know "what and how much", we don't know "how to reduce it".

And monitoring is always the step going along with control activities to reduce pollutants:

Emission Monitoring documents the efficiency of Emission Control Activities.

Components of interest are all gaseous pollutants (mostly CO, SO2, NO, NO2, NOx, THC, HCl, HF, Total Hg, Dioxins & Furans) as well as particulates and their components (%Opacity, Total Dust, Heavy Metals). To ensure comparability standardizing factors (O2 concentration, Temperature, Pressure, Flow or Gas Velocity) are additionally measured and the raw measurement signals recalculated to standard situation (normalization).

The paper will discuss and compare the different ways of continuous online emission monitoring. There are two main avenues of technology, in-situ and extractive monitoring. The sample handling for extractive monitoring can either be direct extractive or dilution extractive. Comparison of the pros and cons will be done.

For the different pollutants, different methodologies of monitoring (detection techniques) have been developed over the years. Similarly, different approaches to continuous monitoring have been developed, ranging from discrete instruments (= instruments measuring only one component) to multi-component instruments, either measuring multiple components with individual detectors or using a multi-component detection technology.

Direct extractive, extractive dilution and direct in-situ methodologies are available. Common to all extractive emission monitoring approach is the fact that the sample must be transported to the detectors via the sampling system, which has to condition the gas sample without influencing the pollutants to be measured. The quality of the sample handling system widely influences the accuracy of the analysers. On the other hand, direct in-situ methodologies, though avoiding any sample treatment and transport, are possibly subject to more and higher interferences and not the required sensitivity / detection limits.

To be comparable the measurement of pollutants needs to follow certain quality assurance guidelines which were developed over the years both in Europe as well as in the USA. These include Equivalency Tests (f.e. "TUEV Test" in Germany) as well as site acceptance tests. There has been developed a major difference between the quality assurance approaches in Europe in comparison to the USA: Europe knows and requires type approvals of instrumentation as well as site acceptance tests, whereas the USA only requires site acceptance tests after installation. Therefore (contrary to Ambient Air Monitoring) there is no general US-EPA approval (type approval of instruments) existing for emission monitors. For the part of the continuous monitoring of the particulate emission there exists another major difference in the regulations: In the USA as well as some other countries mostly [%-Opacity] is the regulated emission value, whereas in the majority of the world (also in India) monitoring of dust concentration [mg/m3] is required.

The paper will also discuss the question: "What is the best emission monitor / monitoring technology, what is the best monitoring strategy to be used for my installation?"