Energy-from-Waste should no longer be coupled with outdated concerns about pollution and in particular the discharge of trace quantities of toxic substances into the locality around an incinerator. In fact the WID, or to give it its true name, the european union Waste Incineration Directive, acted as an important driver and milestone in the progress of development of ever better clean-up processes for incineration plants.
Modem Energy-from-Waste plants are incinerator manufacturer equipped with state-of-the-art air pollution control systems (APC), and they do not any longer impose any real risk to the environment from emissions. The likes of the dioxin scares of the sixties and seventies will not be repeated. EU emission regulations for incinerator have been in-place and strictly enforced since the implementation of the WID toward the end of the 1990, which was instrumental in setting stringent uniform EU wide emission limits.
The first approach has been to install what might be called called front-end techniques. The purpose of these has been to greatly improve the combustion process, control the cooling phase, and implement abatement technologies as early in the process as possible. So. modern incineration technologies are now structured so that the first achievement has been the avoidance of the conditions, as far as is possible, which create these toxins within the combustion process.
While some toxins are still produced the amount is greatly minimised. The second achievement lies in the much improved technology used in the clean up process on the flue gases after combustion, as they pass on their way to the chimney. A wide range of micro-pollutants which are ubiquitous in the environment and therefore present in all waste materials are removed at this stage.
Incinerator bottom ashes are of much reduced mass and volume, but it is important that these can be processed and disposed of sustainably, after the result of the combustion process. These contaminants in the ash need to be characterised carefully. Residual metals may be elevated, for example. However, again by improving the combustion technology, modern incinerators do guarantee a very consistent and high quality ash.
It has been most importantly the ability to achieve a reliably full burnout of the waste, and better control other factors which determine the quality of the bottom ashes, which has moved forward from the incinerators of the past, now no longer operating as a result of the WID.
When we are looking at issues surrounding Energy from Waste plant ash quality and incinerator emissions generally it is also important to maintain a balanced perspective by considering normal practise and emissions levels from industrial and domestic combustion. Incinerator emissions may actually now be much cleaner than their “natural” counterparts. Also comparing the uses to which today’s bottom ashes are being put, against traditional sources of called “natural” building materials, shows the superiority of incineration. Energy from Waste Plant bottom ashes are now being be used, for example, as a substrate for road construction, where they replace what would otherwise be freshly quarried material.
Now, for any government or waste authority to put an over reliance on one waste treatment method would be dangerous. The other EU Waste Directives recognise this and incineration clearly can and must only be implemented as just one of the many waste technologies, which must be developed in each area to implement the so called “waste hierarchy”. The intent of this is to ensure that options such as incineration, and ultimately landfilling as well, only come into play when all materials that can be disposed by other more sustainable methods, such as re-use and recycling, have already been applied to those parts of the waste flow which can be segregated out into those preferable waste streams.
This is the ultimate solution (if good competitive markets become established in these materials), to the issue of handling MSW in an economical and sustainably sensible way. From this realisation, has in recent years, emerged the concept of Integrated Waste Management (IWM). Integrated Waste Management allows each of the established and many new and emerging waste treatment and disposal methods to be used when and where they are most valuable and can make the greatest contribution.
IWM endorses the major principles of waste prevention and its practitioners value optimised recovery from what is in reality unavoidable waste, by diversion from landfill such as by materials recycling, composting, and Energy-from-Waste, and finally but only as a last resort – the landfilling of waste. Landfill, which was for so long the accepted most likely destiny for waste has now become firmly downgraded to being considered the least desired option, throughout the EU.
In many EU member states the planning for waste management is within the legal authority of the regions, sub-regions and other devolved public bodies. While at the turn of the twentieth century it would have been rare to find regions or even municipalities which had a fully integrated management plan. Quite the reverse is now true.
It is the case now that very ambitious targets have been set for increasing the rate of recycling, and reducing the amount of waste sent to landfill. Furthermore, strict targets have also been set for continually reducing the organic content of all wastes sent to landfill.
Almost without exception, all local waste disposal authorities have been forced to take action on waste. Furthermore, any that do fail to take action will soon incur heavy fines from the EU. These will be payable by the local citizens, if they fail to meet the diversion targets in their area.