Alternatives to Incineration

Incineration is a proven, cost-effective solution to many waste management needs, yet it is often only accepted by a community with the deepest reluctance.  Because of its unpopularity, many alternatives have been proposed as better solutions.  These vary from classical methods, such as landfill, through to more complex technological approaches, such as gasification, and novel combined systems, such as MBT (mechanical-biological treatment).

There would be little point in developing a novel technology as an alternative to incineration if it did not offer some significant benefits over an established method.   Developers share a set of common goals (see Table below) but have adopted different approaches to addressing these – with varying degrees of success.

Typical objectives of novel alternatives to incineration •  To recover more resources from waste, preferably as materials rather than energy •  To avoid combustion-based processes, because of their negative image •  To reduce the visual impact of a facility (especially by seeking to avoid the need for a tall chimney) •  To reduce emissions, in particular of dioxins •  Where energy is produced, to increase the efficiency of recovery •  To reduce the creation of secondary wastes and lower dependence upon landfill

This table shows that the main focus is on improving public perception by improving the ‘sustainability’ of waste processing, rather than, for example, reducing the costs associated with waste management.

With our recognised expertise in evaluating novel waste management technologies, we have carried out numerous studies and consulting projects for Public Authorities and private companies, which have considered the relative merits of particular alternatives in a specific context.  Some illustrative Case Studies are listed later on this page.

While it is possible to point to some general advantages and disadvantages of the various alternatives to incineration, it is not currently possible to generalise about which technology is best – the answer will depend upon a number of factors that are specific to the individual circumstances.

It is self-evident that new technologies will be less proven.  Thus, when advising clients, our analysis frequently focuses upon assessing the significance of the advantages on the one hand, and, on the other hand, balancing these against the potential risks of adopting a solution that is unlikely to have been fully proven in commercial operation.

Potential Issues associated with novel alternatives to incineration •  Limited performance data is available with which a proper assessment of their relative merits can be made •  Environmentally desirable concepts may not be economically viable. •  Systems are frequently only proven at small scale; the risks of scaling-up a process are often under-estimated. •  Many developers are relatively small companies with limited technical and financial resources. •  Uncertain economics, which are sometimes dependent upon government economic incentives, make choices    less straightforward. •  Banks are often reluctant to finance projects because of concerns about the operational track record.

The developers of novel technologies have obvious commercial reasons for emphasising the positive features of their systems – which creates a demand for more balanced objective assessments that consider the technical, commercial and environmental performance of processes.  Juniper’s Process Reviews have been used by hundreds of organisations in more than 50 countries across the globe.  They often form the basis of technology shortlists prepared, either by ourselves or others, as part of the decision making process.

Juniper is neither pro- nor anti- incineration.  Along with many independent experts however we do feel that incineration has had a ‘bad press’.  The case against its use is frequently based upon the undeniably poor performance of old plants, now closed.  These earlier plants do not reflect the good environmental record of modern state-of-the-art reference facilities operating at many sites around the world.  But an incinerator can be an inflexible solution in the context of changing amounts and composition of waste; produces relatively large amounts of ash; needs a continuous, steady supply of waste; and is most economic when operated at single large-scale plants.  We therefore see an important role for ourselves and similar organisations to help provide properly balanced, factual information to inform decision makers and local communities about the benefits and dis-benefits associated with its use.  For this reason, Juniper provides customised Briefing Notes that review, in a local context, the true state-of-the-art of all potential solutions.

Equally, whilst some new proprietary processes are strong contenders (providing real advantages when processing particular types of waste) that should in our view be included on shortlists for suitable projects; other systems, sometimes heavily promoted,  are of much more limited value.

Incineration remains the most widely adopted solution, despite its unpopularity.  In essence this is because there are significant issues associated with all alternatives.  These limitations can be grouped into three categories:

•  Many options are only partial solutions (in particular biological and mechanical processes);

•  So far, some commercial systems are only suitable for restricted applications, typically because they have only
   been demonstrated at small scale or on limited types of waste or in only certain configurations;

•  Currently some concepts that are attractive are not economic without government support (for example
   recovering raw materials from waste plastics or tyres via chemical or thermal techniques).

So, while an alternative to incineration may seem attractive, and thus receive political support, it may not be a practical solution when taking into account the need to minimise costs and keep risks under control.

Nevertheless, new processes offer an exciting potential for converting waste into a resource in an environmentally sustainable fashion.  Juniper continues to appraise new systems from throughout  the world in the context of identifying attractive options for our clients.

Alternatives to Incineration
Traditional Methods		Limitations
Landfill		•  Little recovery of resources •  Potentially significant long-term environmental impacts •  Limited availability •  Being phased out in many countries as solution for untreated waste
Composting		•  Only suitable for bio-degradable materials – so not a total solution •  Compost produced from mixed waste has little use and frequently has to    be put on landfill sites •  The environmental impact of many processes can be greater than those    of a modern state-of-the-art incinerator
Recycling		•  Not a total solution.  The residual fraction (which is impractical and    uneconomic to recycle) can be a significant proportion •  Some recovered materials may be of limited usefulness, for which it may    be difficult and costly, or even impossible, to find volume outlets for the    recovered materials, resulting in them having to be converted to energy    or landfilled •  The environmental impact of recycling some materials is often under-    appreciated(for example the impact on the environment of collecting,    sorting, process cleaning and transportation of the materials)
Novel Alternatives (hyperlinks on certain headings are to further information elsewhere on our website)
Anaerobic Digestion			Biological technique produces biogas from waste. Not suitable for many types of waste, but increasingly attractive for others.  When processing mixed wastes is now normally used within an MBT configuration (see below)
Hydrolysis			Biological or chemical partial breakdown of the complex molecules within the waste normally only used in conjunction with other methods.  Interest is growing in the potential of these methods to produce alternative fuels (bio-oil, bio-diesel, ethanol) from wastes. Economics are currently unproven.
Gasification & Co-gasification	Thermal method; produces syngas from waste		Well proven in some specific applications, many at large scale; but progress in other areas has been disappointing so far.
Pyrolysis	Thermal method; produces mix of solid, oil and gas from waste		Very flexible approach, capable of producing wide range of potentially valuable outputs from many types of waste, but commercial track record so far has been disappointing because of economic issues and some poorly performing systems
Plasma	Very high temperature destruction		Originally developed for radioactive and hazardous waste treatment.  Only proven at small scale – seems mainly suitable for ‘exotic’ wastes, though some companies are promoting systems for mainstream applications
Sterilisation/ Autoclaving	Pre-treatment of waste using heat or steam		Interest in this approach for household waste has increased over the last few years because of the sanitisation effect and the ability to recover clean recyclables.  Not a complete solution.
Microwave	Can be used in both a combustion and pyrolysis mode		Few companies developing systems, but commercial track record is limited so far
Irradiation	High energy destruction of waste		Encompasses many types of system (other energy uses eg microwave but also includes techniques using UV, ultrasound) which are essentially experimental at the present time.
Thermal depolymerisation	Breakdown of waste using heat		Term used by some companies to avoid use of phrases such as incineration which have negative connotations.  Could be applied to many types of process, so is not a very helpful descriptor
Other combustion technologies	Wide range of thermal processes for disposal of waste		Such systems generally raise the same issues as conventional incineration.  Some approaches, such as co-combustion in cement kilns, have attracted considerable interest.
Combined approaches
MBT	Combination of mechanical recycling with biological processing		Politically attractive because it appears to avoid the need for thermal processing; but is not a complete solution, so still needs either landfill or thermal treatment of the residual fraction
BMT	Biological-mechanical treatment		Acronym for one of many variants of mechanical biological treatment.  Typically employs a bio-drying stage.
Pyrolysis / gasification / combustion	Numerous proprietary combinations		100+ different systems are being promoted with widely ranging performance, economics and provenness.  Some are very interesting potential solutions for specific projects, but others are not regarded as credible by Juniper at this time.

Case Studies

Case Study 1

Juniper provided a review of Alternatives to Incineration as a focus for a community’s development of their strategy for replacing landfill.  There was little political enthusiasm for incineration, but concerns were expressed about the viability of alternatives; in particular the Public Authority was being exhorted to consider certain specific commercial systems.  In the face of claim and counter-claim about the relative merits of options, we were commissioned to provide an independent report and interactive Briefing session about the environmental, economic and technical advantages and disadvantages of each solution.  This led to further advisory work for the Client. We have carried out a number of closely similar projects for other Public Sector clients around the world.

Case Study 2

We conducted a pre-feasibility assessment that compared the relative merits of several thermal technologies to handle a specific type of waste on behalf of a large multinational client – in the context of bringing the processing of their wastes in-house and using the derived energy to displace fossil fuel consumption on-site, hence helping to mitigate their net greenhouse gas emissions.  Whilst incineration seemed well proven, they were keen to explore other options that might be better in terms of energy conversion efficiency, public acceptance and economics.  Similar techno-economic feasibility studies have been conducted for clients in several industry sectors in Europe and North America.

Case Study 3

Juniper has developed its own proprietary multi-dimensional scoring systems that we use to provide semi-quantitative comparisons of technologies for specific projects.  These have been used to assess Expressions of Interest and Tenders for a wide range of Public Authorities and private sector clients in Europe, Asia and North America.  For example, we assessed over 50 different proposed alternatives to incineration, encompassing a range of biological, thermal, chemical and mechanical systems and processes, that were submitted in response to a worldwide Open Invitation by the Government of Hong Kong to submit alternatives to incineration for processing some 4 million tonnes per annum of waste in what is the largest such procurement programme of its type in the world.

Juniper has comprehensive databases that track the performance of the alternatives to incineration and an unrivalled knowledge base of processes under development around the world.  Please call on +44 (0) 1452 770078 to discuss how we can help, or email.