Written evidence submitted by Biocentre Technology Ltd

[WME 0059 Rev]

Waste Management in England

Executive Summary

1. We see the work this committee is doing as extremely important – our experience is that public procurement is simply not selecting the most sustainable waste treatment solutions. Yet waste is an extremely valuable resource for the UK, and best use of it important to our economy and environment.
2. UK engineers developed world leading waste treatment in the 1980’s and 90s with government support. This treated mixed waste as a resource, to yield high grade recylcates and a refined, sustainable fuel which could be used as a clean replacement for coal. The process is generically called MBHT. The process has been further refined and has unrivalled environmental and sustainability credentials. It can achieve recycling rates well in excess of 90%, recovery of biogenic (renewable) energy efficiency, well above 60% at substantially lower costs than incineration.
3. As the keepers of a version of this MBHT technology, we present evidence that far from being outcome orientated and technology neutral, public procurement continues to favour hugely expensive, inefficient, harmful and inflexible incinerators. These are misleadingly presented as renewable energy, when in truth it is mainly plastic (material which should be recycled) that is being burnt, often in very inefficient processes. Evidence is presented to support our assertions of perverse interpretation of policy and institutionalised bias towards incineration which cannot be supported by scientific, engineering or sustainability data.
4. In our view policy should be outcome based and technology neutral, seeking to encourage solutions which are sustainable, that is:

• Preserve the material resource in waste, particularly rare and valuable material
• Have the best impact on the environment, including carbon footprint
• Meet the needs of local people and communities
• Are economically attractive and sustainable
• Are flexible to changes and improvements in technology and recycling.
   

5. In particular we would encourage consideration of the following:

• Ensure the waste hierarchy is intelligently applied consistently with tools that take a look at the overall environmental impact such as WRATE.
• Ensure all waste is pre-treated (sorted and recylcates extracted) before incineration. Ban the incineration of material that can and should be recycled such as plastics and WEEE.
• Implement strong measures to discourage the incineration of valuable material resource in waste, recognise the resource value of heavy metals present in most residual waste streams. Exclude aggregate from the definition of recycling unless it contains no significant higher grade material.
• Apply landfill tax to waste treatment energy recovery which generates less than 40% of the energy in waste, certainly on new facilities. (Inefficient use of a valuable resource should not be subsidised!)
• Develop frameworks to help recyclates back to products. (End of Waste criteria and processes).
• Define high grade biomass fuel derived from waste sources to be regarded as a product and so categorised as recycling rather than recovery (the product would need to be from biogenic sources, not include valuable recylcates and of a high quality to directly replace coal, or virgin biomass. Develop the WRAP criteria for refuse derived fuel grades, and include an End of Waste grade.[1]
• Set a maximum allowable contract length on public contracts for waste treatment. This is to prevent ‘locking in’ of waste treatment which delivers poor sustainability performance and is inflexible to changes in technology or recycling rates. A maximum of ten years is recommended.
• An immediate stop of all further public procurement of incineration based waste treatment solutions that cannot demonstrate full adherence to sustainability criteria. In particular no incinerators should receive consent that do not include full pre-treatment (sorting and recycling) of input residual waste prior to incineration, or that achieve levels of energy efficiency below 40% (typically those that do not include use of waste heat with local industrial users of the heat)

Introduction and Background

6. This submission is written from a technical perspective, and presents evidence that the effect of the policy and public procurement has been prejudicial to the use of best available technology in this field. Nevertheless we wish to encourage technology neutral, outcome based legislation and policies. Outcomes must be sustainable – that is deliver environmental, social and economic sustainability. Our experience is that there continues to be a strong public sector bias towards incineration, despite it being demonstrably inferior on most all measures of sustainability, vastly more expensive and inflexible.
7. This evidence has been prepared by engineers from Biocentre Technology Ltd (BTL), a UK waste to recyclates and fuel technology business. BTL owns intellectual property relating to an advanced Mechanical, Biological and Heat Treatment (MBHT) process for residual waste. Similar (although generally less evolved) technology is available from other MBT suppliers, although output fuel quality is a key issue.
8. This MBHT technology, offers substantial environmental and economic benefits in the treatment of waste. The process emerged from systematic engineering thinking regarding waste as a resource which could deliver economic value, indeed the UK plants using this process built in the 1990’s and beyond were producing valuable recylcates and clean fuel profitably – even before the effective subsidies of current legislation (eg landfill tax). Unfortunately “clumsy” legislation in the late 1990’s effectively nearly killed off this fledgling industry.
9. Our experience is that current practice in local authority procurement continues to be strongly biased towards incineration, despite it being demonstrably inferior on all sustainability measures, including being inflexible (prejudicial) to future improvements in recycling technologies. The recent public inquiry on the planning decision for the proposed Gloucestershire incinerator shed light on this, with damaging arguments (to the environment and economy) seeming to hold sway[2]. We would welcome the opportunity to present specific evidence on this.
10. The MBHT process was developed by teams working for senior engineer and industry expert Tony Manser[3] who is a member of BTL and party to this submission.
11. MBHT processes mixed black bin bag waste from municipal or commercial sources (residual waste) into recyclates and a high quality biomass fuel. Typically around 50% of the material is recovered to recyclates including plastics and metal with the balance being converted to fuel.
12. This fuel is low in contaminants and can be burnt in standard biomass and coal plants more cleanly than the fuel it is displacing. The fuel is over 90% Biogenic from sustainable sources (food, paper, card etc). As a high grade product which can be used in place of virgin biomass it can reasonably be considered recycled material itself. Thus the MBHT process recycles to useful product over 90% of the material from a residual bin, clearly this is a vast improvement on disposal or low grade energy recovery. There are very substantial environmental benefits of this approach.[4]
13. In the 1990’s Tony Manser was part of a government working party that obtained derogation for the UK from the then emerging Waste Incineration Directive for burning of this fuel because it was a manufactured product with consistent specification which could be burnt more cleanly than the fuel it replaced, without significant production of dioxins etc[5].
14. Unfortunately this derogation was not applied, we understand this was for fear of lower quality “RDF” (refuse derived fuel) from inferior processes. RDF is a loosely used term to cover everything from what is little more than shredded waste, to a high quality refined fuel which can be used to directly replace coal. [6] This loose definition is unhelpful and results in good quality fuel product made to a consistent specification being confused with shredded waste.
15. The consequence of this clumsy legislation was to ‘throw the baby out with the bathwater’ and effectively almost kill off this fledgling UK industry, to be replaced by demonstrably inferior incineration technologies, typically derived from overseas plants. We hope that policy can now halt this damaging move towards mass burn incineration (MBI). MBI fails to recycle from the residual waste stream and burns a dirty fuel so has to rely on hugely expensive and inefficient processes to ensure sufficiently clean emissions.
16. It is well known that Biomass from otherwise waste sources produces the lowest Carbon footprint and most sustainable form of this fuel. We have millions of tonnes of waste still being wasted (in landfill, or increasingly sent to MBI in the UK and elsewhere) which has the potential to be converted into this valuable fuel, this can displace fossil fuels notably coal, delivering a great improvement in carbon footprint[7].

Responses to the committee’s request for evidence:

1.              the ability of existing recycling policy measures to ensure that England reaches the EU target of recycling 50% of household waste by 2020;

17. Source segregation and roadside sorting can achieve moderately high levels of recycling, although there are certain types of collections where this will always be limited. It should be noted that manual sorting and collection is inherently inefficient and undesirable, from the visual and community issue of multiple roadside bins to the damage caused by additional collection vehicles. This should be considered in the balance when looking to increase source segregation. In many cases sorting recylcates (preferably automatically) from a mixed bin can give superior environmental, economic and social consequences.
18. We seek to illustrate this from evidence that emerged at the recent public inquiry into the planned incinerator in Gloucestershire. Incredibly this incinerator is designed without any pre-treatment, so it plans to burn the entire, unsorted residual waste stream in Gloucestershire, despite this stream containing significant amounts of valuable recyclates including rare heavy metals in batteries / WEEE and plastics which should be recycled not burnt. [8]
19. Incinerators should pre-treat material prior to energy recovery – this would improve efficiency, carbon footprint, lower costs and most importantly recover valuable recylcates before they were degraded in an incinerator.  This is ‘second chance recycling’ and is crucial to driving up sustainable treatment of our valuable waste stream
20. This type of treatment would yield very significant benefits as shown in appendix 3. From data of the Gloucester residual bins, which we can assume are typical of this type of black bin bag waste, if put through a suitable MBHT process we would see most of the residual waste being recylced:

• 6.8% rejects – so 93.2% is recycled (about half of which is a refined biomass fuel which may currently be termed recovery)
• 46.53% processed, cleaned and refined into a sustainable biomass fuel. This fuel is classed as renewable (Biogenic, from sources recently growing). Fuel of this quality can reasonably be regarded as recycling since it is putting material back to useful purpose, in place of an equivalent virgin product (virgin biomass).
• All other material (some 47% of this ‘residual’ stream) is recylced – and put back to economic use. This recylcate is high grade. Metals are preserved and recovered. This is very different to the very low grade ‘aggregate’ which may be recovered from incinerator bottom ash.

21. If this County achieved 60% recycling prior to sending to the residual bin to a MBHT type process this would yield a total recycling rate for the County (after the second chance recycling) of 78.7%. In addition 18.6% of all waste will be manufactured into a high grade, sustainable and renewable fuel which can be used to directly displace fossil fuel. (97.3% recylced to useful product)
22. Note that the use of this recycled biomass as fuel is environmentally far superior to the use of virgin biomass sources. It is far better in sustainability terms not to grow trees for fuel, but to first use these to make paper, recycle the paper to lower grade uses, then when the pulp is uneconomic resuse for even card for say egg boxes, use this as a fuel.
23. Thus the total recycling rates (total proportion of material put back to use in place of virgin material) in a typical County can reach 97.3% without putting additional burdens on households or businesses – this surely should be encouraged!
24. Incineration of raw residual waste streams without pre-treatment (sorting) to extract recylcates should be heavily discouraged, indeed a total ban may be appropriate. New facilities such as that planned for Gloucestershire should not be allowed without pre-treatment unless it can be proven that further recycling of the residual stream is not economically feasible.

2.              whether England’s national recycling targets should be higher than those stipulated by the EU; and the pros and cons of compulsory household waste recycling;

25. We would argue that by encouraging the right residual waste processing facilities; ie those that can automatically extract, sort and clean recyclables from the residual waste stream; the need for compulsion to achieve high levels of recycling is not there. (see also above)
26. There is also some risk in simply driving for higher recycling rates, rather than driving for outcomes with the best net environmental outcome. For example running multiple collection vehicles for many different waste streams may be less desirable than collecting material in one or two bins and automatically sorting later.
27. Paper pulp degrades and becomes uneconomic to keep recovering, at some point it becomes better for the environment (including the carbon footprint) to use this biomass as a fuel.  It is obvious and proven that this is environmentally superior to growing virgin biomass for direct use as fuel. For this reason it is important that production of high grade biomass fuel (perhaps grade 1 fuel as defined in the new WRAP standard[9]) that can be used as a product in place of coal or virgin biomass is classified as recycling.
28. There is evidence that the term recycling is being crudely interpretted to justify processes that are hugely damaging to resources. For example the conversion of incinerator bottom ash into a low grade aggregate for use in roadfill seems to be classified as recycling. The bizarre consequence of this that the distruction of valuable rare metals present in WEEE and batteries in an incinerator is encouraged[10]. Gold and other valuable metals (present in WEEE) is literally being burnt to form roadfill and policy seems to be encouraging this as it can be called recycling.
29. We would argue that policy should encourage the use of tools such as WRATE (a tool to measure the environemental outcome of different waste processing technologies supported by DEFRA) to drive to the best environmental outcome, rather than just focussing on the waste heirachy. Indeed there is loose wording to this effect in government advice. However as the Gloucestershire Planning inquiry has shown, it is easier to argue that moving up the waste heirachy from disposal to ineficient recovery is a step up the waste heirachy than it is to argue for solutions that produce a signficantly better environmental outcome[11].
30. We recommend that this should change and the emphsis should be on the best environmental outcome that is economically realistic.

3.              the role of businesses and households in municipal waste recycling and recovery;

31. As explained above, good residual waste processing facilities will drive much better rates of recycling and recovery, this reduces the need to over burden householders and businesses to sort waste.
32. However if residual waste processing is by Mass Burn Incineration (MBI) then valuable recyclates in the waste stream will be incinerated or greatly devalued. MBI is also hugely expensive and inflexible, eg the Gloucestershire MBI plant is part of a £500M contract with a 25+ year life. In this case it becomes essential that households and businesses are strongly encouraged (if not mandated) to recycle material prior to the stream sent to the incinerator. However we would rather see pre-treatment of residual waste prior to this type of incineration being mandated.
33. Ironically if recycling prior to MBI is very successful the residual waste stream will not contain the plastic material needed to “fuel” the incinerator (moisture rich waste, eg food waste, does not burn without significant activation energy, provided by a fuel such as plastic), and the quantity of waste left for the incinerator may be far less than its capacity.
34. In other words building MBI (incinerators) drives the need for higher levels of recycling obligations on others, which if successful obviates the need for the incinerator in the first place.
35. Policy should encourage the development of flexible facilities which extract recylcates prior to using material which cannot be economically recovered as a fuel to displace fossil fuels.

4.              whether England has the right balance of waste treatment technologies between anaerobic digestion, incineration with energy recovery and gasification to produce fuel/heat/power;

36. Policy should be technology neutral and drive outcomes such as sustainability, preserving valuable resources and be economically attractive. We should be flexible to improvements in technology.
37. However, our experience is that there have been perverse drivers which have encouraged the over development of incineration (with energy recovery), and these seem to be continuing. We would welcome the opportunity to present evidence on our experience of the public procurement process for residual waste treatment which seem to continue to favour high cost, strong balance sheet backed incineration over economically and environmentally superior solutions.
38. These perverse drivers include public procurement process, simplistic interpretation of the waste hierarchy rather than best environmental outcome, targets on renewable energy which reward low efficiency use of a valuable renewable energy resource (waste), and illogical interpretation of procurement risk.[12]
39. Incineration (with energy recovery) by its nature is:

• Relatively inefficient. Typically yielding just 20% recovery of the available energy in the waste stream, where alternatives can extract 50% or more.
• Expensive and inflexible. For example the 220 ktpa incinerator due to be built in Gloucestershire has an efficiency of c20% and will cost over £170M to build as part of a 25 year, £500M contract. This is not flexible to future improvements in waste treatment and recycling.
• Backed by large, multi-national firms with strong balance sheets that can support a very large contract
• Demanding on input material – there are minimum needs in terms of quantity, energy density, CV etc which tends to discourage recycling and pre-treatment prior to incineration
• Wasteful of valuable resource. For example metals entering the process largely destroyed by the incineration process, in some cases producing harmful bi-products.
• Produces heat away from where it can be used or is needed. Fuels (including waste) should be burnt where heat is needed.

40. An example of the undesirable way policy is being interpreted can be seen in glib, “poor science” claims that EfW (incinerators) plants produce renewable power. In practice only a small proportion of energy from a typical incinerator is from renewable, Biomass/Biogenic sources. Biomass in residual waste streams is typically wet (think of trying to set fire to a potato) and so requires considerable energy to burn off this water.  Incinerators often use plastic rich fuel to provide this energy. If the plant is inefficient (for example it does not include Combined Heat and Power, CHP) then we are deliberately burning a fossil fuel (plastic) in an inefficient process to burn wet biomass and claiming this as renewable power. This produces a vastly inferior carbon footprint.  Bizarre, yet precisely the claims being made for the planned Gloucestershire incinerator.
41. The effect of burning off water in wet biomass is analysed in detail in appendix 4. In conclusion for the Gloucestershire incinerator (as an example) rather than the claimed 52%, just 37.8% of useful power output is from the renewable proportion of the residual waste stream, the balance coming from plastics. Given the very inefficient process (not CHP) the plant only generates 14.5MW of useful power from 190ktpa of plastic rich waste. In this example this means the county will generate just 5.48 MW of renewable energy from an enormous investment of public money – a £500M contract. Not good use of public money and far more expensive than other sources of renewable energy.
42. We argue that the current interpretation of policies is not outcome based, but biased towards incineration, even when it can be demonstrated that this is inferior in environmental and economic terms. We would encourage policy that redressed this balance. In particular the following should be encouraged:

• Maximising the retained material value in recyclates, preserving high value, rare and expensive material. Do not allow burning of metals.
• Minimise the burning of material that is fossil derived (plastic).If it is burnt for power (or converted into fuel including liquid fuels for power) ensure this is done in efficient processes which can demonstrably deliver superior environmental outcomes to the use of virgin fossil fuels
• From residual waste material which is best used for energy (ie this gives the best environmental outcome, this will be the Biogenic fraction) target high levels of energy recovery, in excess of 50% should be the minimum target
• Do not allow long term public contracts (more than ten years) for waste treatment facilities, unless these can be proven to offer extremely high levels of resource and energy recovery. It is essential that our waste treatment policy is flexible to improvements in technology, locking valuable waste streams into inefficient and wasteful 25 year contracts is very damaging and must be stopped.

5.              the extent to which increasing the capacity of thermal treatment plants could impact England’s municipal waste recycling rates;

43. Thermal treatment plants such as incinerators that place demands on the constitution of input material (residual waste) will inevitably drive collection and recycling policies that ensure this mix is supplied to the plant. This they achieve either by limiting the mix in a residual bin (eg don’t remove too much plastic) or by adding material from other sources to ‘enrich’ the mixture (eg plastics rich C&I waste added to a mix).
44. It is important therefore that waste treatment plants whether thermal or otherwise should either be very robust to input waste mix or they must be flexible to future change. As an example the incinerator planned for Gloucestershire has a 25 year contract life (30 year+ expected life) and has a need for input material with adequate CV, energy density and low activation energy requirements. In other words it is a plant which will impact future recycling rates in Gloucestershire because it cannot adequately flex to changing mix.

6.              whether anaerobic digestion is the best option available to deal with food and other biowaste; whether the Government’s Anaerobic Digestion Strategy and Action Plan has substantially increased the use of AD;

45. We encourage policy which is outcome driven, and therefore technology neutral. Anaerobic Digestion may be the best current method of treating certain types of biowaste. It is not however suited to all biowaste, and other technologies may produce superior environmental outcomes. For example In Vessel Composting (IVC) (aerobic decomposition) of suitably prepared material can produce excellent outcomes.

7.              and the feasibility of the introduction of a ban on landfill and/or incineration in England.

46. Outcome based policy for waste treatment should, as far as economically reasonable:

• Minimise any harmful environmental impact, and maximise positive environmental impact.
• Minimise carbon footprint (the Global Warming Potential) of waste treatment
• Maximise the recovery of valuable resources
• Avoid the destruction or significant devaluing of material resources, in particular valuable metals
• Be flexible to changes in technology
• Meet the needs of local people and communities

47. Incineration of residual waste which has not been pre-treated breaches a number of these principles. For this reason we would support a ban on incineration of the following materials, unless it can be shown that it is not economically feasible to further recycle (pre-treat) the material prior to incineration:

• Plastics – A WRAP report[13] (and elsewhere) show that recycling plastics is significantly superior in environmental terms to combustion for energy, particularly if done in a low efficiency incinerator without CHP. The waste hierarchy is unambiguous, plastics should be recycled if feasible and viable.
• WEEE – including batteries.
• Plastic and metals, including heavy metals present in batteries and small electronic appliances can be recycled if separated prior to incineration. They are irrecoverable afterwards, indeed heavy metals can contaminate the incinerator bottom ash.
• Non-ferrous metals. Aluminium and other metals are heavily degraded and reduced in the incineration process, and tend to be deposited as salts in the IBA or fly ash. They should be recycled prior to incineration

48. Waste processors would then be obliged to ensure residual waste streams were fully pre-treated to recover recyclable material prior to incineration.
49. We see no specific benefit in a ban on landfill and suggest that it may lead to some perverse effects (such as the burning of plastics in incinerators[14]). We should be encouraging sustainability, and this means policy should be flexible and encouraging to superior technology, and must not lock in unsustainable practice such as inefficient burning of mixed waste.

May 2014

Appendix 1: Evolution of the UK MBHT / Biocentre process – UK can lead the world in treating waste as a resource

50. This appendix gives the background to the development in the UK (over 30 years) of an advanced process which extracts recylcates and produces a high grade, refined >90% biomass fuel, an excellent sustainable source of biomass for power. The process is generically advanced Mechanical, Biological and Heat Treatment (MBHT).
51. The appendix also gives some background as to why, despite these advantages and the “home grown” nature of the MBHT technology, UK legislation and policy has encouraged and subsidised the deployment expensive non-UK solutions, in particular “EfW” incinerators, which are vastly inferior for the (UK) economy and environment. However it is still difficult to understand why UK public procurement continues to enter very long term contracts for inefficient and wasteful incinerators, we believe that in the interest of the UK economy and sustainability this should change.

The History

Background

52. Thermal treatment of raw wastes entered the waste management hierarchy in the UK one hundred and forty years ago with the construction of the first municipal incinerator in Nottingham. These early incinerators were extremely primitive, consisting of a series of combustion cells that were loaded manually with mixed municipal wastes.
53. The early plant became superseded by mass burn units where the exhausts were cooled in spray towers in an attempt to remove as much of the fly ash as possible. However, the plants were still inefficient and wasteful, in that none of the heat from combustion was recovered. This issue was later addressed by delivering the hot gases from combustion to specially designed boilers, where the steam could be used for district heating and electrical power generation.  Plants of this type replaced the early mass burn units and became common, but increasing environmental regulation required an almost continual process of modifications to reduce or eliminate pollutant emissions to atmosphere (Dioxins, Furans, toxic fly ash) and to ground (bottom ash and furnace slag).
54. Although the heat recovery incinerators enjoyed popularity for many years, the steady increase of recycling initiatives began to have an adverse effect upon them. As more and more of the higher calorific fractions were recovered, the calorific value of the residual fractions going to incinerators reduced, generally to a level of around 9.5 MJ/kg. At that level the residual wastes are hardly combustible, and they frequently required the assistance of supplementary fuels to improve combustion. This dramatically reduced the efficiency and economic viability of plants generating power or supplying district heating.  In some plants an attempt was made to screen out the materials that were detrimental to combustion (mainly organics and inerts such as glass and soils), and to thereby increase the calorific value of the remainder.  That, however, left the problem of how to dispose of the screened out fractions, and while aerobic digestion was possible and was implemented, the resulting product was too contaminated for use as a compost. It could only be landfilled, thereby limiting the value of incinerators as a disposal route.

Development of the UK MBHT Process For Fuel Production

55. In the late nineteen-seventies, in an attempt to find an alternative to incineration, the concept of using the wastes as a raw material for a solid fuel that could be consumed in industrial boilers was conceived, under the generic title of Waste Derived Fuel (WDF). Five plants were built – four sponsored by the Department of the Environment and one commissioned independently by East Sussex County Council (ESCC). The DoE plants were of a common design, but they suffered from their being unable to effectively separate contaminants from the fuel products, and they were not a commercial success. The ESCC design was fundamentally different, and the fuels it produced were of a much higher quality and calorific value. The ESCC design incorporated Mechanical Biological and Heat Treatment (MBHT) stages. The fuel products produced found ready markets at attractive prices in power stations and industrial consumers, to the extent that the plant did not have the production capacity to satisfy the demand.
56. The ESCC MBHT plant was successful largely because it was designed according to a different philosophy. The early DoE plants were simply seen as a means of disposing of wastes, with the products being almost an afterthought. However, the engineers who designed the ESCC plant (Tony Manser and team) took the approach that if the plant was going to be of value to waste management, then it should be seen to be a commercial producer of a value-added product for which the raw material happened to be wastes. The design philosophy targeted product quality and not waste disposal. The process was designed to eliminate contaminants to the greatest extent possible. As a result the calorific value was much higher because the process removed the non-combustibles and contaminants at several stages, reducing the ash contents to similar to those of coal, and also reducing the moisture content to less than eight percent. This created a fuel that was made almost entirely out of paper and card, with some wood, plastics, and traces of textiles.

Evolution

57. This MBHT technology then evolved through a series of five plants, further improving the separation and treatment processes without major changes to the original design, and employing increasing levels of automation culminating in the two large fully automated plants built for Slough Heat & Power and Castle Cement in 2003 and designed by Advanced Recycling Technologies (ART) Ltd founded by Tony Manser and others in 1991. The intellectual property of ART was acquired by Biocentre Technologies Ltd in 2012 with the intention of developing a series of MBHT process plants throughout the UK.

A fuel production plant built by ART in 2003 – processing 230,000 tonnes a year of wastes with no atmospheric emissions.

58. While the calorific value of the products is important, the removal of inert contaminants is equally so.
    The only boilers in which one can burn raw wastes or low-grade waste derived fuels (WDF) are those specifically designed for incinerators, and they are very different from conventional boilers. If one tried to burn those materials in an industrial boiler it would destroy it in weeks. Superheaters clog up with fused ash and suffer from massive high temperature tube erosion that can reduce a tube thickness by several thousandths of an inch a week — which means the tubes burst in about three months of service. Gas pass tubes also suffer badly from grit erosion, and those in the furnace are attacked by flame erosion since the flame length from crude wastes is much longer than from conventional fuels. Since the chloride and Sulphur contents in raw wastes and low grade WDF are high, boiler air heaters in the exhaust gas passes suffer from condensation of hydrochloric acid, and the Sulphur combines with moisture at temperatures below 250°C to form Sulphurous acid which, being unstable, breaks down into Sulphuric acid. 
59. Crude wastes and low grade WDFs also contain high levels of silicates, and these fuse on boiler tubes in the high temperature zones. Because they fuse at lower temperatures than the rest of the fly ash they migrate to the tube surfaces. Silicates (sand) were once used by blacksmiths when welding iron together by forging, because silicates have a fluxing property. Meanwhile, boiler tubes always have a rust coating, but once that is established it protects the tube from further corrosion. The silicates flux that away, allowing the acidic flue gases to once more attack the tubes every time the soot blowers are operated, and again leading to tube failures in months.

Dioxins and furans

60. There is also the issue of dioxins and furans (Polychlorinated Dibenzodioxins and Poly chlorinated Dibenzofurans) with which conventional boilers cannot deal.  These are not manufactured products, but they do arise from a number of sources, including municipal incinerators, forest fires, coal-fired power stations, and many other natural and man-made combustion processes.
61. The EU Waste Incineration Directive (WID) require boilers burning wastes or low grade fuel to maintain an exhaust gas temperature of 250°C in order to prevent dioxins and furans from reforming. Industrial boilers are trying to get the maximum amount of heat energy possible from fuels, rather than heating the local atmosphere. In many incinerators this issue is addressed by using oil-fired after burners in the exhaust gas passes, but that rather defeats the object of burning waste derived fuel in the first place. Fuels made in the Biocentre MBHT process are sufficiently free from contaminants, and in the next generation of plants no longer include plastics, so that they do not create dioxins or furans in measurable quantities. This was demonstrated as long ago as 1985 by the then Associated Heat Services Ltd  in the first of their combustion plants to use the fuel, where tests for dioxins and furans did not discover detectable quantities of either.
62. The sophistication of the Biocentre MBHT process, and its ability to remove contaminants including heavy metals, is such as to offer the treatment of a wide range of wastes including household wastes without any need for any separation at source. This is a potentially important contributor to the reduction of waste management costs that have been growing exponentially for a number of years. It has been achieved by many years of research and development by ART Ltd and later Biocentre Technology Ltd, leading to the creation of mathematical modelling computer programs and data bases that permit processes to be designed with confidence.
63. In recent years the desire to reduce the reliance upon fossil fuels and to substitute renewable low carbon footprint biofuels in their place has led to a growing interest in how waste materials could be exploited. This has resulted in the WRAP (Waste and Resources Action Programme) classification scheme for biofuels derived from wastes. In this scheme there are five classes established according to the pollution potential, metals, ash, moisture and heavy metals contents, ranging from Class 1 (best) to Class 5 (worst).

Biocentre solid fuels – pellet form

Component                            WRAP Limit              WRAP Class             

Biomass content                            >90%                            Class 1                                         

Net CV                                                        >15 MJ/kg              Class 1-3                                         

Moisture content                            <10%                            Class 1                                         

Chlorine content                            <0.2 %                            Class 1                                         

Ash content                                          <10%                            Class 1                                         

Bulk density                                          >650 kg/m3              Class 1 (optional)                                         

Mercury content                            <0.02 mg/MJ              Class 1                                         

Cadmium content                            <0.1 mg/MJ              Class 1                                         

Sum of heavy metals                            <15 mg/MJ              Class 1                                         

Specification of Refined fuel produced by MBHT process such as Biocentre.
Data from Slough, Castle Bromwich and other plants.

64. As can be seen with MBHT it is possible to use a well proven process to produce a high grade, refined fuel which is rich in biomass and low in contaminants and valuable recylcates. This fuel burns well and can (and has) been used as a direct substitute for fossil fuels such as coal, producing a very significant economic and environmental (particularly carbon footprint) benefit. The UK has many millions of tonnes of residual waste still being wasted and this is a valuable resource for the country.

MBHT – Advanced Mechanical, Biological and Heat Treatment

65. MBHT is the generic term for the processing technology developed by Tony Manser and associated engineers. It is a sophisticated form of Mechanical and Biological Treatment (MBT) of wastes which includes fuel refining stages, including a flash dryer. The specification and quality of the output fuel is closely controlled – and achieves the high levels of performance quoted above which allow the fuel to be used as a direct replacement for washed singles coal or wood pellets / chips.

Questions and Answers

66. Q1:              Why is doing all of this any different from simply burning wastes?
    A1:              Because it involves highly sophisticated and computer controlled mechanical processing to produce fuels that have far better emissions controls when used and far lower life cycle impacts.  The MBHT process also focuses on extracting and refining the recyclates at the earliest stages so avoiding the incineration or destruction of waste materials that could otherwise be used as raw materials once they have been separated and refined.
67. Q2:               So what about dioxins and furans that dwell for hundreds of years in the environment and poison people (e.g. through bioaccumulation)?
    A2:              The Biocentre products are highly refined, and they are no more likely to create dioxins and furans than are wood fuels and much less than forest fires, incinerators, and coal burning.
68. Q3:              Why has this technology not been used more widely?
    A3:              The UK was in the lead for this technology in the 1980s, and it achieved an offer of derogation from the EU Waste Incineration Directive (WID) in 1990. Unfortunately, the British government at the time rejected the derogation. This set the fledgling industry back by at least twenty years.
69. Q4:              What about global warming and the burning of fuels that releases carbon dioxide into the atmosphere?
    A4:              Biocentre fuels are manufactured from renewable materials (mainly residual paper and card – not suitable for recycling) which, during their growth phase, absorbed carbon from the atmosphere. When they are burned they release no more than that which they first absorbed so they are at least carbon neutral, particularly since they contain no materials of fossil origin. The carbon content of Biocentre fuels is 60% less than that of coal, but the volatile matter is nearly three times that of coal, so there is less carbon to burn. In addition, the paper industry claims that it plants two trees for every one that it uses for pulp. Therefore, the use of fuels made from recovered paper, card, and pulp might actually have an environmentally beneficial effect in reducing the atmospheric carbon balance. An independent assessment of the Biocentre process using the standard Environment Agency’s WRATE tool concluded that for every tonne of waste processed by a Biocentre plant there is a net saving of 550kg of CO2 equivalent, far better than any comparable process. See also appendix 5
70. Q5:              So why don’t we simply recycle paper and card into new paper and card?
    A5:              All recycling leads to “down cycling.” This means that a sheet of clean white paper eventually ends up in low grade fibre products such as an egg box, by which time the fibre length has become such that it cannot be used any more. It ends up as a sludge that the paper mill has to get rid of, to incineration or landfill. The MBHT process escapes this route by efficiently capturing the energy remaining in the material after a useful life.
71. Q6:              So why aren’t many more companies offering this technology?
    A6:               They are (or something they think is similar). MBT (Mechancial Biological Treatment) processes from a number of companies are becoming increasingly evolved.  We encourage the development of MBHT type technology from whatever source, it delivers demonstrably better outcomes – far greater sustainability – than other forms of waste treatment, in particular incineration. (see above)
72. Q7:               What is the record of use of these fuels in combustion plant?
    A7:              The Biocentre fuels have been used in industrial boilers and processes for many years (power stations, cement works, market gardens, prisons, and even for a while in the 1980s, in the domestic market where the fuel pellets were much sought after. The combustion technology and adaptations to this fuel is well understood and has been scientifically tested and verified in operation.

Appendix 2: Extract from WRAP final report on “Domestic Mixed Plastics Packaging and Waste Management Options” June 2008

73. The UK has long understood that plastics should not be burnt but recycled. In fact analysis shows that incineration in an EfW plant (with or without energy recovery) is so detrimental to the environment that even landfill is superior. (eg see below a report produced by WRAP in 2008)
74. Nevertheless implementation of UK policy seems to continue to encourage the development of mass burn incinerators (MBI) such as the one currently considered for Gloucestershire which has no pre-treatment of the residual waste to remove the high proportion of plastics present. In fact MBI typically require the plastics because of their high energy density, effectively they are used as a fuel to drive off the water present in the wet organic waste in the residual bin. An MBI uses plastic, effectively a fossil fuel, in an inefficient process to dispose of waste, rather than drying and cleaning organic matter first so that it can be used as a fuel in itself, and recycling the plastic for use in new products. For the sake of the environment this should stop, incineration of plastics, with or without energy recovery must be strongly discouraged. MBI’s without pre-treatment to remove plastic from the residual waste stream should no longer be built.

Extract from WRAP final report on “Domestic Mixed Plastics Packaging and Waste Management Options” June 2008

http://www.wrap.org.uk/content/domestic-mixed-plastics-waste-management-options

Appendix 3: Extraction of Recylcates From Residual Waste – Second chance recycling and the benefits of pre-treatment prior to incineration

75. Whatever the source / roadside segregation scheme there will always be a residual waste fraction. This so called residual waste contains high levels of recylcates which can be extracted economically and put to useful purposes. It is wrong to treat the residual bin as ‘waste’ to be sent to landfill or incineration. By cleaning and sorting from this residual bin we have a ‘second chance recycling’. Second chance recycling would greatly increase recycling rates in the UK, as the following analysis shows.
76. If you treat residual waste to recover recylcates and produce a high grade, dry fuel you can dramatically improve the environmental impact of the overall process. This is illustrated through independent assessments using DEFRA’s WRATE tool (see appendix 5). The Global Warming Potential (GWP, colloquially known as Carbon Footprint) of a process incorporating MBHT and use of the fuel in a power station such as Slough Heat and Power (as occurred through the 2000’s) gives very substantial Carbon benefits.
77. We argue that there is much scientific and field evidence to support policy that would ensure that as a minimum all residual waste sent to incinerators should first be pre-treated to extract recylcates and condition the waste/fuel to enable more efficient combustion.
78. Summary of potential benefits of pre-treatment:

• Increased levels of recycling prior to EfW. This is a requirement of planning law including EN1[15]
• Recycling of material which cannot be recovered post incineration, including heavy metals
• Removal of plastics for recycling, or efficient conversion into fuel (including high quality fuels for eg aviation). This is far more efficient than burning in mass burn incineration, and is recommended by DEFRA [16]
• Removal of most water greatly increasing the efficient of combustion
• Removal of contaminants such as chlorine to give a fuel which burns cleanly without the production of Dioxins and Furans. This greatly simplifies flue gas treatment and reduces the height of the required chimney stack
• Producing consistent fuel with high energy density and consistent burning characteristics
• Increasing the biomass content to over 90%, and removing water greatly increases the renewable proportion of energy produced.
• Greatly simplifying and reducing the size of combustion plant required. The required height of any building can be 20m or less.
• Allows the biomass fuel to be transported to where it is needed. For example it would be far more efficient to ship biomass fuel to a local heat user for use in their own biomass boilers than to try to ship steam.
• Biomass fuel from waste represents the most sustainable form of biomass (far better than growing virgin crops)
• Greatly increases the quantity of energy produced from a given waste input.

79. BTL have conducted a detailed mass balance calculation using data from the recent Gloucestershire public inquiry. This analysis the treatment of residual waste streams in Gloucestershire through a pre-treatment plant (in this case using the known performance data of the Biocentre process) to analyse the impact of pre-treatment prior to an incinerator.
80. In summary from the Gloucester residual bins, which we can assume are typical of this type of black bin bag waste, if put through a suitable process we would see:

• 6.8% rejects – so 93.2% is recycled (about half of which is a refined biomass fuel which may currently be termed recovery)
• 46.53% processed, cleaned and refined into two forms of fuel. These are both >90% biomass (biogenic, is from material that was recently growing and is sustainable). This fuel is classed as renewable and will earn the user carbon credits of some form (currently Renewable Obligations Certificates). This fuel burns cleanly and is effectively from sustainable, biogenic sources. Fuel of this quality can reasonably be regarded as recycling since it is putting material back to useful purpose, in place of an equivalent virgin product (virgin biomass).
• All other material (some 47% of this ‘residual’ stream) is recylced – and put back to economic use. This recylcate is high grade and can be refined into product which can replace new material. Metals are preserved and recovered. This is very different to the very low grade ‘aggregate’ which may be recovered from incinerator bottom ash.

81. If Gloucestershire achieved 60% recycling prior to sending the residual bin to a Biocentre type process this would yield a total recycling rate for the County (after the second chance recycling) of 78.7%. In addition 18.6% of all waste will be manufactured into a high grade, sustainable and renewable fuel which can be used to displace fossil fuel. If this is also classed as recycling (as it should if it is being used in place of virgin biomass) then the 97.3%
82. It is a requirement of law and of planning policy that only residual waste that cannot be reasonably recycled can go to energy recovery. Clearly this analysis shows that pre-treatment will recycle a signficant proportion of residual waste – this second chance recycling is very important for achieveing the high levels of recycling targetted in the waste heirachy.

83. In addition the fuel is of greatly enhanced quality to the raw residual waste which enables much more efficent conversion of the fuel to power. The Sankey diagram below is derived from detailed performance data for the combusion of the type of refined fuel advocated here. More details can be provided.
84. It is helpful to look at the relative energy production of this overall process compared to that from the proposed Gloucestershire incinerator (as an example of current incineration thinking)
85. This shows that with appropriate MBHT pre-treatment delivering fuel to suitable conversion process (typically combustion) the total energy output from 190,00 tpa of Gloucestershire residual waste would be:
    21.7 MW electricity output PLUS
    24.9 MW heat output
86. Alternatively all of the energy output can be used for heat in which case the process delivers 51.4 MW of fuel suitable for a heat plant. This compares to just 14.5 MW of net electrictrical output from the proposed incinerator. (17.5MW gross)
87. In summary the appropriate pre-treatment prior to a suitable EfW process would yield:
    Up to 47.8% more recycling of the residual waste stream to plastic, high grade metals and glass etc
    A further 46.5% of residual waste recycled into a high grade biomass fuel suitable for displacing coal, or virgin biomass.
    Up to 200% more energy from the recovered proportion
    A GMP (carbon footprint) up to 400% better than the proposed incinerator
88. This evidence shows why it is important that policy encourages outcome based policy and legislation, and essential that public procurement embrace the benefits of sustainable developments. This should be flexible to technology improvements. Incineration should be discouraged, particularly where it is inefficient (does not include heat recovery). Incineration of recylcates still present in a residual waste stream should be stopped, and pre-treatment mandatory for incinerators, except where there is no economic recycling possible.

Appendix 4: Proportion of Energy from an incinerator EfW plant that is from renewable biomass sources

89. It is all too often claimed that energy produced in a waste incinerator – so called energy from waste (EfW) – is renewable. This is a simplistic claim which can result in very poor decisions for the UK economy and environment. A worked example from the recent Gloucestershire planning public inquiry is given below
90. Residual waste contains biogenic waste (ie waste from material that was recently growing) – energy produced from this is reasonably classed as renewable. In addition there are other materials, some of which (plastics) can also be burnt to release energy.  Of course the energy produced from burning plastic is not renewable. Plastics should be burnt for energy, but rather recycled (see appendix 2). However if you were to use plastics for fuel it is very important to do this in an efficient plant and process. Unfortunately incinerators are hugely inefficient due to their need to burn off water and manage a very dirty fuel. As an example the planned Gloucestershire incinerator has an efficiency (power out versus energy in the residual waste) of c20%. This compares to over 60% for a well-designed, efficient process (see appendix 3)
91. As an example, the applicant for the planned Gloucestershire incinerator makes the claim that based on historical waste mix data 52.6% of the energy in the residual waste stream comes from biomass (biogenic) material and so can be classed as a renewable energy source. (even this requires a paper and card rich source of Commercial and Industrial Waste to ‘enrich’ the municipal residual waste streams.)
92. However this is just the proportion of the calorific value (CV) of biomass in the residual waste, it does not equate to the proportion of power produced from the biomass fraction. In the same way that cardboard has calories but will not make you fat we must also look at the conversion process to calculate the proportion of power which can be classed as renewable. Biomass contains far more water than the plastics, and water requires much energy to “burn off”. Energy is required for what is called “activation energy” (the energy required to ignite the material) and to liberate (evaporate) the water in the material. The wetter the material the more energy is lost. Incinerating unprocessed food waste for example which is typically 70% moisture takes more energy to deal with the moisture than is released from the materials CV.
93. 96% of the energy available from biomass comes from paper and card, itself a recyclable material. It is important that this material is kept dry otherwise further renewable energy may be lost.
94. If you subtract the lost energy in dealing with water from the available energy you can calculated the proportion of power generated by the proposed Gloucestershire incinerator which can be attributed to biogenic (renewable) sources, see table below
95. From this more careful analysis it can be seen that just 37.8% of the power produced by the proposed development can be classed as renewable – that is coming from biogenic / biomass sources.
96. For the Gloucestershire example, given a claimed net electrical output of 14.5MW for the plant this means the county will generate just 5.48 MW of renewable energy (48000 MWh per annum) from this enormous investment. The contract cost is around £20M per year so this gives a cost for renewable energy of £416 / MWh, 4 times the cost of other renewable sources such as wind[17] - and a 25 year financial commitment from local taxpayers.
97. The Gloucestershire project is being promoted as producing renewable energy and helping towards local and national targets. Given the grow inefficiency of the process and the use of plastic to fuel the process this is wasteful of the energy in waste, and unhelpful in our goals to use waste as a resource to provide energy and material resources. This is further explored when looking at the Carbon Footprint (Global Warming Potential, as measured using the WRATE tool from DEFRA) – see appendix 5.
98. It is very important that policy drivers do not encourage the inefficient conversion of the available energy in the biogenic content of residual waste. Burning of fossil derived fuel (plastics) should be strongly discouraged. Policy and incentives (such as ROCs) that recognise the overall process energy efficiency (with targets in excess of 50%) and the proportion of energy which is renewable (with targets above 90%) should be pursued. Inefficient incineration and the incineration of plastics which could be economically recycled must be stopped.

Appendix 5: Sustainable design of Waste Treatment Facilities – WRATE and The Waste Hierarchy

99. BTL can produce extensive third party analysis comparing the environmental impact of different waste treatment solutions. These comparisons typically use the DEFRA WRATE tool, which looks at a number of factors including the ‘Carbon Footprint’ of different solutions (which it calls Global Warming Potential or GWP). We present here just a brief summary of that analysis.
100. The chart below looks at the carbon footprint (GWP) of real data from a number of waste treatment methodologies. EfW here is an incinerator (in Sheffield) which incorporates Combined Heat and Power. (CHP) Clearly EfW which does not incorporate CHP performs far worse. In all cases the input is mixed municipal waste.

101. By far the best performing process is ‘ART’, this is an MBHT process supplying fuel to industrial users such as Slough Heat and Power.
102. This type of whole cycle, outcome based analysis as supported by the WRATE tool is an effective way of guiding policy and procurement decisions.
103. The waste hierarchy is well understood, and if properly applied also supports sound sustainable decision making. Unfortunately as became very clear at the recent Gloucestershire planning inquiry, the waste hierarchy can be simplistically interpreted to produce perverse conclusions.
104. It can be argued that in ‘moving up the waste hierarchy’ a step change is all that is recognised in law. This thinking would argue that one facility that achieved the R1 threshold (so could be classed as recovery rather than disposal) was much the same as any other recovery facility.
105. This is mistaken thinking – it is wrong for the planet, runs counter to the objectives of all policy in this area, runs counter to sustainability principles and fails the ‘common sense’ test, clearly generating twice the renewable energy is superior for environment linked planning objectives. It also seems wrong in law.
106. Unfortunately the well-considered sustainability principles behind waste policy, and seemingly enshrined in waste legislation[18] do not seem to be being applied in practice. For example, in Gloucestershire the principle argument in favour of the planned incinerator was that it was a step up the waste hierarchy from disposal to recovery. The need to ensure the best overall environmental outcome was not interpreted as an obligation (so it seems), nor was much apparent weight given policy which encourages efficient conversion of energy from residual waste.[19]

107. At the recent public inquiry in Gloucestershire It was shocking to hear that the applicant felt under no obligation to consider the environmental outcome of its proposed development, but that the obligation is simply to move one step up the waste hierarchy, in fact they seemed to make it clear that they regard delivering a better environmental outcome as immaterial to their application.
108. In this example the authority is well aware (from their own WRATE analysis) that alternative EfW methodologies deliver a significantly better “overall environmental outcome”. Three such independent comparative reports were examined, show that in terms of overall environmental outcome the ranking , from worst to best is:
     - Landfill (worst)
     - Mass Burn Incineration (MBI) with no CHP
     - MBI with CHP
     - MBT (of various types) supplying fuel to a dedicated EfW plant
     - MBT (of various types) supplying fuel to an industrial user. (best)
109. In this Gloucestershire case, there were strong arguments made suggesting that pre-treatment of waste prior to incineration was not necessary or required in law, and that burning unsorted residual waste was in the community’s interest. This is despite the strong evidence that pre-treatment could substantially improve recycling rates and net energy production (see also appendix 3)
110. In addition plastics and other material present in WEEE should be recycled prior to incineration since the material is destroyed in the incineration process.
111. It is strongly argued that if UK public authorities can still enter £500M contracts for an inflexible incinerator (25 years) which will burn unsorted residual waste, burning valuable resources inefficiently we are interpreting the waste hierarchy and principles behind it perversely. That we should place a huge tax burden on local communities (through the landfill tax, which results in waste contract at c£100 per tonne for the ‘disposal’ of residual waste is for this perverse goal is hugely undesirable.
112. Our evidence is that policies should be re-examined to ensure that action is outcome driven, with outcomes being sustainability orientated. Sustainable for the economy, environment and communities.

May 2014