Emissions Abatement, including Flue Gas Treatment

The disposal of waste by thermal treatment processes (such as incineration, combustion, gasification, pyrolysis, plasma and microwaves) is beginning to replace the traditional and widespread practice of landfilling. Suitable landfill sites in many countries are diminishing and landfill costs, where this can still be operated, are increasing. A number of regulations spurred by the efforts towards sustainability have also hastened the move in recent years away from landfilling.

The shift towards thermal waste degradation methods is associated with the benefits of energy recovery from the waste materials, the production of recyclable by-products and the reduced volume of solid waste that is produced.

Although some of these thermal treatment processes have been used for a number of years, only more recently have an increasingly stringent and expanding array of regulatory controls been introduced to control the potentially toxic emissions (gas, liquids and solids) associated with thermal waste processes. These regulatory controls are mainly driven by environmental forecasts, public opinion and health concerns, and their implementation has a significant impact on the capital and operating costs of thermal technologies. In this financial and environmental context, control of emissions has therefore taken centre stage in the development and operation of thermal waste treatment processes.

The variety of waste arisings around the world falls under the broad categories listed below;

• Biomass
  
• Industrial waste
  
• Municipal waste
  
• Plastics
  
• Sludges
  
• Tyres
  

These wastes have a very different chemical makeup and the emissions produced are also dependent upon the type and nature of the thermal destruction process utilised. For example, the pyrolysis of a waste leads to significantly different emissions from the incineration of the same waste. Most conventional pyrolysis processes generates char, syngas and oils, while incineration produces an ash and flue gases.

Juniper’s experts understand how the various thermal treatment technologies work as a result of our continuous appraisal of such systems around the world over the last 10 years. We are therefore in a unique position to assess the impact on emissions of the raft of techniques and process conditions that have been implemented in the hundreds of thermal treatment processes worldwide many of which we have already reviewed in our off-the-shelf publications. We also understand the fundamentals of operation of the various technologies for flue gas and syngas cleanup; such as abatement techniques for dioxins, VOCs, acidic gases (e.g. SO2, NOx, HCl, HF, H2S) heavy metals and particulates.

We have conducted a number of projects on emissions from thermal waste treatment which include the following:

Case Study 1

A Japanese multinational asked us to assess the potential for reusing bottom ash from Municipal Waste Incinerators

Case Study 2

We were recently commissioned to perform and independent appraisal a emerging UK pyrolysis and gasification system which included an assessment of all emissions and the emissions abatement methods that were in place

Case Study 3

We have reviewed the benefits of Selective Catalytic Reduction (SCR) for power plant deNOx applications

Case Study 4

We were asked by a major US multinational to look at Volatile Organic Compound (VOC) abatement using thermal oxidisers and compare this with other systems types of VOC abatement (e.g. such as catalytic and adsorption)

Case Study 5

We have compared SCR and Selective Non-Catalytic Reduction (SNCR) for one of our clients

Case Study 6

We were commissioned to look at novel catalytic systems for gaseous emissions abatement