The NLHPP will use proven technology to capture and control particulates, including ultrafine particles

Myth: “The facility won’t be able to filter ultrafine particles

The fact: The ERF will use proven, highly effective technology to capture and control particulates, including ultrafine particles. The UK Air Quality Action Group, which is the country’s leading and most authoritative expert body on air quality, is clear that modern ERFs are very effective at controlling particulates and ultrafine particles. There are multiple scientific studies to back this up.

The new ERF will, like the existing plant, use ‘baghouse filters’ to capture particulates. This technology is recognised by air quality experts, including the UK’s Air Quality Expert Group, as extremely effective for capturing particulates.

The particles are removed by four separate mechanisms: impaction; interception; diffusion and electrostatic collection.

These efficient filters are able to remove particles that are much smaller than the pore size of the fabric. This means that very small particles, known as ‘ultrafine particles’ are captured alongside larger particles (ultrafine particles are less than 100 nanometres. A nanometre is one thousand-millionth of a metre).

There is a growing scientific awareness about the health impacts of ultrafine particles. It is recognised that the major sources are road vehicle exhausts and aviation (particularly beneath flight paths).

The Air Quality Expert Group is clear that, in contrast to these sources, energy recovery facilities are highly effective at filtering ultrafine particles. It states that: “There have been a number of studies of municipal waste incinerators which show highly effective removal of UFP by their pollution control systems”.

In 2016 a peer-reviewed academic study from the University of Birmingham examined the emissions of ultrafine particles from energy from waste facilities. It found that:

  • After dispersion and dilution, the level of UFPs is indistinguishable from those that would occur in the absence of an incinerator

  • In some cases, the ultrafine particle concentration in the flue gas may be below that in the local ambient air

For more information, please see the Air Quality Expert Group’s 2018 report Ultrafine Particles (UFP) in the UK. The report was prepared for the Department for Environment, Food and Rural Affairs.