Continuous emission monitoring ensuring cleaner air and better safety
Emission monitoring refers to the ongoing processes of collecting data on the gases and components released in the air by industrial plants. In this article, we will discuss the ABC of emission monitoring at a general level: What is emission monitoring? What needs to be taken into consideration when planning a well-oiled measuring process?
What is emission monitoring?
By regular and continuous industrial air emission monitoring at industrial settings, researchers and air quality controllers aim to find out what those sky-high chimneys of industrial plants in our skylines shoot out to the atmosphere, and whether the findings are within the limits approved by the local authorities.
Despite the modern and efficient industrial gas purification systems, it is possible that industrial plants discharge small amounts of pollutants that are harmful to health and the environment, which is why continuous emission monitoring is needed. Even though emission monitoring is a standard and fairly straightforward process for all industrial plants, it is of the utmost importance: it protects nature and human beings proactively and ensures the safety of us all.
The local emission limits are determined in environmental permits, which each industrial plant is bound to follow, and are not allowed to operate without one. According to these permits, industrial plants are juridically liable for controlling and measuring their own emissions on a regular basis. In addition to the ongoing monitoring processes by the plants themselves, accredited laboratories do standardized spot checks on the emissions and emission processing equipment at industrial plants regularly.
Why are environmental standards & emission monitoring necessary?
As the economy and industries grow globally, the number of industrial plants increases concurrently. This, in turn, calls for constant development in environmental legislation and permits. It is also natural that over time, current methods need updating and new, enhanced ways to monitor industrial actions are being implemented. One of the ways that help industrial plants and local authorities forecast and adapt to changing circumstances is by continuous monitoring of emissions.
A good example of a fairly new addition to the components that industry stakeholders are required to measure from the air is Mercury (Hg). Due to the deviant nature of Mercury, it wasn’t added to the EU standards of emissions until fairly recently.
All in all, the benefits of emission monitoring is two-fold:
- It creates a common framework for standards and keeps the emissions at a set level. Continuous measurements can also affect future research and in the course of time turn the focus to new or increased components (such as Mercury).
- It can decrease the level of harmful emissions and make the air cleaner. This can also have a positive effect on an industrial plant, as emission monitoring can point out weak spots in the processes and help optimize them.
How does emission monitoring work?
In Europe, the air emissions are carefully standardized by the EU (Industrial Emissions Directive, IED), and further monitored by the member countries’ national authorities. These standards and directives work as frameworks for national authorities, who interpret and apply the standards in relation to the target country’s legislations. With the help of the common framework, environmental authorities are able to create localized permits and legislation that fit their cultural, juridical and environmental contexts.
Which components are being measured depends on various factors, such as the industry, the size of the plant and what is required by the environmental permit. For example, both small and large coal-fired power plants have their own regulations.
Emission monitoring is a standard procedure
As stated earlier, emission monitoring is a fairly standard process and a basic requirement, which benefits everybody and which all industrial plants should be familiar with.
However, before carrying out emission measurements, it is vital that the plant is familiar with its own permit. The first step is to internalize, which gases and components they are required to monitor and what their set limits are.
What is more, it is vital paramount that plants choose appropriate technologies and devices for emission monitoring. It should be secured that the device is sensitive enough to detect even the smallest levels of a component, as some industrial plants have very low and strict emission limit values for certain gases.
According to the general guide for emission monitoring by Technical Research Centre of Finland, it is also fundamental to invest a sufficient amount of time and effort in effective and careful planning before carrying out any measuring. Planning should include mapping out the nature of the process and its possible variations, as these factors might help choose the most suitable methods and equipment for measurement.
Once the most suitable method for the continuous emission monitoring has been decided, the measurer can use the following procedure, recommended by the Technical Research Centre of Finland :
- Choosing the measuring platform
- Choosing the flange mounting locations
- Analyzer installation and possible calibration
- Choosing a number of measuring points and locations in particle sampling
- Gas flow rate measurement for isokinetic sampling and to determine the volume flow (if needed)
- Sampling & continuous measurements
- Handling of samples and possible calibration
- Calculating results
Together with the air quality standards and continuous emission monitoring industrial plants can be better committed to ensuring better air quality that protects us all: the environment, people in it, and those working at industrial plants.
Source: The Technical Research Centre of Finland Ltd: Päästömittausten käsikirja osa 1: Päästömittauksen perusteet (2007)