The VW scandal raised the level of public awareness on air pollution, highlighting the importance of accurate, reliable monitoring and the drive to reduce measurement uncertainty, reports Susan Fearn Ringsell.
Awide range of industrial activities have to monitor their emissions to air while demonstrating compliance with limits for key pollutants.
This is required to protect the environment, but in many instances it also provides insights that can be used for process optimisation.
“For example,” says Ken Roberts, managing director at Quantitech, “we supply multigas analysers to Thetford Power Station which are used both to monitor emissions for regulatory compliance and to help manage the efficiency of the combustion process.”
Smaller processes with less harmful emissions can incorporate periodic monitoring to demonstrate compliance, whereas larger ones, with the potential to produce higher levels of pollution, require the installation of continuous emissions monitoring systems (CEMS).
All of the emissions regulations in the UK are derived from EU Directives, and a level of uncertainty exists following the Brexit referendum
Ken Roberts, managing director, Quantitech
“Monitoring data for the smaller ‘Part B’ processes are submitted to local authorities, [while data for] the larger ‘Part A’ processes are regulated by the Environment Agency in England, by Natural Resources Wales, and by the Scottish Environmental Protection Agency.
“All of the emissions regulations in the UK are derived from EU Directives, and a level of uncertainty exists following the Brexit referendum,” says Roberts.
The escape of chemical pollutants into the environment either by air or water can pose a major environmental risk, not just on industrial sites, but also to the surrounding area.
“With increasingly stringent requirements covering industrial emissions to the environment, plus the threat of stiff financial penalties, it is vital for companies to ensure that their operations are fully compliant at all times,” says Darren O’Neill, industry sector sales manager – analytical measurement at ABB.
Introduced in January 2011, the industrial emissions directive (IED) places a particular emphasis on the use of both equipment and procedures that constitute best available techniques (BAT).
BAT effectively sets a benchmark for industrial companies in the way that they both measure and manage their emissions and effluent flows, with many organisations being responsible for monitoring and reporting their own output.
Choosing the right analytical equipment for an application can be a difficult process which requires consideration of a number of factors over and above the device itself.
With increasingly stringent requirements covering industrial emissions to the environment, plus the threat of stiff financial penalties, it is vital for companies to ensure that their operations are fully compliant at all times
Darren O’Neill, industry sector sales manager – analytical measurement, ABB
“To ensure a thorough monitoring regime, organisations must plan carefully,” explains O’Neill. “Most crucially, all potential releases, whether to air or water, need to first be identified and categorised.”
Consideration must also extend to the potential for fugitive emissions, including the most likely points where leaks may occur and the composition of the emissions themselves.
In the event that a site has some form of treatment plant installed, there is the added requirement to be able to measure the composition and strength of a gaseous or liquid emission.
For both air and water-borne emissions, users will be obliged to choose instruments from the approved MCERTS list, but there are still choices to be made within that.
O’Neill adds: “The accessibility and clarity of the data is another issue, which includes the data acquisition and reporting system (DARS) associated with the instrumentation.
“Looking beyond the equipment itself, reputable equipment suppliers are another great source of support and advice, so it’s important to pick the right one.”
Efficient environment
With increasing demand for efficiency improvements, process operators are looking for equipment that not only meet the regulatory performance requirements, but is also robust, reliable in the long term, and simple to operate.
Roberts explains: “FTIR [fourier transform infrared spectroscopy] has become one of the most popular emissions monitoring technologies, largely because of its ability to measure multiple compounds simultaneously.
“The Gasmet portable and CEMS FTIR analysers comply with all of the standards mentioned above, providing process operators with the opportunity to utilise approved analysers that are relatively simple to operate.”
Risk reduction
From a risk management perspective, it is vital that emissions monitoring does not suffer any downtime because this will result in a requirement for the industrial process to stop, which can be extremely costly.
Says Roberts: “Many of Quantitech’s FTIR CEMS customers also operate a portable version of the same technology – a Gasmet DX4000.
“This provides a multigas monitoring instrument that can be used at other points in the process, but which can also be deployed quickly if the CEMS requires checking or a back-up.”
With the aim of reducing complexity and improving the ease with which emissions monitoring can be undertaken, Quantitech has launched a new integrated system capability.
These systems are designed to meet site-specific requirements and are able to include the measurement and logging of all required data.
While based on the Gasmet CEMS IIe, it can also include appropriate approved instrumentation for the measurement of TOC [toral organic carbon], oxygen, particulates and flow.
Future proof
“Process operators may choose to install individual analysers for each of the parameters specified in their permit, or they may prefer a multi-parameter technique such as FTIR,” says Roberts.
Customers are able to specify target compounds for simultaneous analysis at the time of ordering. However, importantly, further compounds can be quickly and easily added at a later date, which means that the monitoring system is future-proof, says the company.
The ability to detect a wide variety of compounds also highlights the appearance of unexpected gases that may arise as a result of problems or inefficiency in a process.
Back pages
Process operators are increasingly looking at the back pages of MCERTS certificates because these provide a greater insight into the performance of emissions monitors.
“Particularly good measurement uncertainty figures for parameters such as formaldehyde, hydrogen fluoride, nitrous oxide and methane have increased the demand for Gasmet FTIR analysers,” says Roberts.
Abatement technology continues to improve and environmental emission limits are likely to lower, so there will be a greater demand for instruments that are able to measure a wider number of parameters reliably at lower concentrations.
Meanwhile, testing and production facilities experts Climeworks [pictured above] has recently launched the world’s first commercial plant that captures atmospheric CO² for supply and sale to a customer.
The Swiss direct air capture company launched the commercial-scale direct air capture (DAC) plant, featuring its patented technology that filters carbon dioxide from ambient air.
The plant is now supplying 900 tonnes of CO² annually to a nearby greenhouse to help grow vegetables.
During the capture process, CO² is chemically deposited on the filter surface. Once the filter is saturated, the CO² is then isolated at a temperature of about 100°C.
The pure CO² gas is sold to customers in key markets, including: commercial agriculture, food and beverage industries, the energy sector and the automotive industry. Companies can utilise this atmospheric CO² in carbonated drinks or for producing carbon-neutral hydrocarbon fuels and materials.
With Brexit negotiations in the air, it is difficult to make future predictions on emission monitoring with a high degree of confidence. However, the UK has ambitions to continue trading freely with the European Union and it is unlikely that this would be possible if the UK did not implement similar, or even the same, environmental legislation.
