CEMS: An Overview


Courtesy of a1-cbiss

We've written an overview to where CEMS are required, types of site that require CEMS and future requirements.

Continuous Emissions Monitoring Systems are used to continuously collect, record and report data from industrial process operators that produce emissions to air.

CEMS are used as a means to comply with stringent emission limits as regulated by the Environment Agency (EA).

Under the Environmental Permitting Regulations, the EA or local council will refer to European Legislation, the Industrial Emissions Directive (IED 2010/75/EU).

Sites are required to continually measure emission parameters from their chimney-stacks to ensure that they are compliant, as defined in their site permit.

Who Regulates the CEMS Market?
In 1998, the EA introduced the MCERTS scheme to provide tighter controls for emissions to air including a technical specification that CEMS had to meet.

The criteria of the scheme included: detection limits, response time, linearity, zero and span drift etc.

A requirement of the scheme, any CEMS equipment used to monitor emissions must also be approved and certified.

Any new installation seeking a permit will need to comply with the Industrial Emissions Directive (IED).

The EA are looking at bringing all existing permitted sites under the directive.

The IED supersedes seven directives under one directive, creating a more simplified legislative framework:

  • Integrated Pollution Prevention & Control (IPPC)
  • Large Combustion Plant Directive (LCPD)
  • Waste Incineration Directive (WID)
  • Solvent Emissions Directive
  • And three Titanium Dioxide Directives

Under the new changes set by the IED, large combustion plants will be affected by the new emission limit values (ELVs).

This will be particularly significant to the future of coal fired power stations.

Where are CEMS Installed?

Most CEMS installations are utilised in applications where power is generated or where waste is burnt.

Fuel consisting of fossil fuels, gas or waste is burnt or heated at very hot temperatures to produce heat or power or both to generate electricity.

CEMS Processes:

  • Mass Burn Incinerators
  • Thermal Treatment - Gasification or Pyrolosis
  • Boilers
  • Turbines

Coal Fired Power Plants - An Uncertain Future?

In fossil fuel powered plants, environmental protection has seen a greater focus.

Although the UK has seen air pollution declining since the 1970’s, the IED has demanded a market for technologies to address Nitrogen Oxides (NOx) and Sulphur Oxides (SOx).

In general, power plants with a greater capacity than 50 MW are required to measure NOx and SOx continuously plus dust and particulate matter (PM) emissions.

Energy from Waste - A Solution to the UK’s Waste Problem

The UK is faced with the problem of disposing waste as many landfill sites are full. An increased number of EfW sites would decrease the amount of waste being sent to landfill significantly.

EfW’s are regarded as a solution to the growing amount of waste in the UK generating up to 70MW of energy.

Municipal thermal treatment sites are required to typically measure SOx, NOx, CO, HCl, NH3, VOC and TPM which now fall under the IED.

EfW sites are seen as a ‘greener’ method of waste disposal as they reduce the emission of the greenhouse gas and methane produced during waste composition from organic matter in landfill sites.

Biomass - A Greener Alternative

The UK government supports biomass, as a low-carbon form of power generation compared with fossil fuels.

The trees and plants used as fuel absorb carbon dioxide from the atmosphere as they grow, so if they are regrown under environmentally sound conditions, burning them results in a net carbon saving as it displaces coal and gas.

However, green campaigners point to problems with sourcing sufficient quantities of biomass, much of which has to be imported, and say that without strict regulations, growing trees and crops for biomass can lead to deforestation in developing countries.

Under the new rules set by the IED, coal-fired power stations must either comply with certain emissions limits or opt out – Operators choosing to opt-out are then allowed a certain number of hours of operation before they must be shut down.

A Solution to the UK’s Growing Waste Problem?

Currently, the UK generates around 30 million tonnes of municipal waste each year. Of that:

  • 35% is recycled or composted;
  • 10% is used to recover energy (EfW);
  • 55% is sent to landfill

The growing volume of waste, a shortfall of landfill sites and increasing energy prices are making Energy from Waste an obvious solution for a cleaner environment whilst filling the gap of power generation left by the coal fired power stations.

Are We Facing an Energy Crisis?

The majority of the UK’s electricity comes from coal fired power plants. In 2011, the IED came into force.

The directive gave high polluting coal fired power stations a period of grace to comply with the new requirements highlighted in the directive.

If sites choose not comply, they are faced with closure.

The IED will require non-compliant power plants to close by the end of 2016 or after 20,000 operating hours.

With low coal prices making coal-fired power plants more profitable than gas, many time-limited coal-fired power plants have raced through their allocated hours already and will close this year.

Estimatations suggest that over 12000MW of generating capacity could be lost from the national grid following the closures in 2016.

There is a real possibility that we could be facing a ‘lights out’ situation.

Incentives for Capturing Syngas from Gasification Process

The Renewables Obligation (RO) places a commitment on UK electricity suppliers to source an increasing proportion of electricity they supply to customers from renewable sources.

The gasification process converts municipal solid waste into a usable synthetic gas, or syngas.

Renewables Obligation Certificates (ROCs) are issued to accredited generating stations based on net renewable generation.

The fuel is sampled using the process agreed during the accreditation process, factoring in the calorific value of the fuel being burnt, and this is then used to determine the renewable generation for ROC claim purposes.

More efficient plants will receive up to 2 ROCs per MW/hour of electricity produced.

Why Landfill Isn’t Sustainable:

  • EU Landfill Directive requires the amount of waste to be reduced
  • In 2014, landfill taxation rates have increased from £72 per ton to £80 per ton to encourage diversion from landfill
  • Majority of landfill sites are full
  • Methane gas produced by landfill has a GWP of 21 which means it offers 21 times the greenhouse warming threat than CO2

Customer comments

No comments were found for CEMS: An Overview. Be the first to comment!