Advanced Thermal Treatment of

Municipal Solid Waste

www.defra.gov.uk

Contents
Preamble

1.

Introduction

2.

How it works

3.

Markets and outlets for the outputs

11

4.

Track record

13

5.

Contractual and financing issues

16

6.

Planning and permitting issues

18

7.

Social and perception issues

23

8.

Cost

24

9.

Contribution to national targets

25

10. Further reading and sources of information

27

11. Glossary

28

Prepared by Enviros Consulting Limited on behalf of Defra as part of the New Technologies Supporter Programme.
We acknowledge support from the Department for Environment, Food & Rural Affairs (Defra), the Department of
Communities & Local Government (DCLG), the Environment Agency (EA) and BeEnvironmental Ltd.
This Document has been produced by Enviros Consulting Limited (Technical Advisors) on behalf of Defra to provide
assistance to Local Authorities and the waste management market generally through awareness raising of the key
municipal waste management options for thediversion of BMW from landfill. The Document has been developed in
good faith by the Advisors on behalf of Defra, and neither Defra not its Advisers shall incur any liability for any action
or omission arising out of any reliance being placed on the Document by any Local Authority or organisation or other
person. Any Local Authority or organisation or other person in receipt of this Document should take their own legal,
financial and other relevant professional advice when considering what action (if any) to take in respect of any waste
strategy, initiative, proposal, or other involvement with any waste management option or technology, or before
placing any reliance on anything contained therein.
Any interpretation of policy in this document is that of Enviros and not of Defra or DCLG.
Crown copyright, 2007
Cover image courtesy of Energos, ENER.G Group

Preamble
This Waste Management Technology Brief,
updated in 2007, is one of a series of
documents prepared under the New
Technologies work stream of the Defra Waste
Implementation Programme. The Briefs
address technologies that may have an
increasing role in diverting Municipal Solid
Waste (MSW) from landfill. They provide an
alternative technical option as part of an
integrated waste strategy, having the
potential to recover materials & energy and
reduce the quantity of MSW requiring final
disposal to landfill.
This Brief has been produced to provide an
overview of Incineration Technology, which
recovers energy from the combustion of
MSW. Although not a new technology it can
potentially form part of an overall integrated
waste management strategy to divert MSW
from landfill. Other titles in this series
include: An Introductory Guide to Waste
Management Options, Advanced Biological
Treatment, Mechanical Biological Treatment,
Mechanical Heat Treatment; Incineration,
Renewable Energy and Waste Technologies,
and Managing Outputs from Waste
Technologies.

There technologies can assist in the delivery

of the Governments key objectives as
outlined in the Waste Strategy for England
2007, for meeting and exceeding the Landfill
Directive diversion targets, and increasing
recycling of resources and recovery of energy.
The prime audience for these Briefs are local
authorities, in particular waste management
officers, members and other key decision
makers for MSW management in England. It
should be noted that these documents are
intended as guides to each generic
technology area. Further information can be
found at the Waste Technology Data Centre,
funded by the Defra New Technologies
Programme and delivered by the
Environment Agency (www.environmentagency.gov.uk/wtd). These Briefs deal
primarily with the treatment and processing
of residual MSW. Information on the
collection and markets for source segregated
materials is available from Defra and from
ROTATE (Recycling and Organics Technical
Advisory Team) at the Waste & Resources
Action Programme (WRAP).
The Defra New Technologies Demonstrator
Programme has provided nine projects aimed
at proving the economic, social and
environmental viability (or not) of a selection
of waste management technologies. For
information on the demonstrator projects see
the Defra website or email
Wastetech@enviros.com.

1. Introduction
Municipal Solid Waste (MSW) is waste
collected by or on behalf of a local authority.
It comprises mostly household waste and it
may include some commercial and industrial
wastes. Historically, nationally the quantity of
MSW has risen year on year1, presenting a
growing problem for local authorities
particularly as legislation, now limits (by
implication2) the amount of mixed MSW that
can be sent to landfill, becomes more
stringent over time.
One of the guiding principles for European
and UK waste management has been the
concept of a hierarchy of waste management
options, where the most desirable option is
not to produce the waste in the first place
(waste prevention) and the least desirable
option is to dispose of the waste to landfill
with no recovery of either materials and/or
energy. Between these two extremes there
are a wide variety of waste treatment options
that may be used as part of a waste
management strategy to recover materials
(for example furniture reuse, glass recycling
or organic waste composting) or generate
energy from the wastes (for example through
incineration, or digesting biodegradable
wastes to produce usable gases).
At present more than 62% of all MSW
generated in England is disposed of in
landfills3. However, European and UK
legislation has been put in place to limit the
amount of biodegradable municipal waste
(BMW) sent for disposal in landfills4. A key
driver for this focus on biodegradable waste
is to reduce the uncontrolled release of
greenhouse gas emissions to atmosphere. The
Landfill Directive also requires waste to be
pre-treated prior to disposal. The diversion of
this material is one of the most significant
challenges facing the management of

Municipal Solid Waste in the UK.

There are a wide variety of alternative waste
management options and strategies available
for dealing with Municipal Solid Waste to limit
the residual amount left for disposal to
landfill. The aim of this guide is to provide
impartial information about the range of
technologies referred to as Advanced Thermal
Treatment (ATT) the principle ones being
gasification and pyrolysis. These technologies
are designed to recover energy (in the form of
heat, electricity or fuel) and can contribute to
the diversion of BMW from landfill. They are
part of a range of new alternatives currently
being assessed and investigated through the
New Technologies work stream of Defra.
Further details about the new technologies
featured in this report are available from
Defras Waste Technology Data Centre:
http://www.environment-agency.gov.uk/wtd
The technologies described in this Brief
Advanced Thermal Treatment - have a limited
track record in the UK (and indeed
internationally) on MSW. There are many
examples of ATT processes that are
established are viable and bankable on
various waste streams (e.g. biomass, industrial
wastes, tyres etc) but a lesser number proven
on municipal wastes. The aim of this
document is to raise awareness of the
technologies available and help remove
barriers to the development of appropriate
ATT processes in England.
This guide is designed to be read in
conjunction with the other Waste
Management Technology Briefs in this series
and with the case studies provided on Waste
Technology Data Centre. Other relevant
sources of information are identified
throughout the document.

1 This is now showing signs of slowing and in some areas waste arisings are falling, and indeed in 2005/6 there was a 3% fall nationally.

However this may be partly explained by other factors occurring in that particular financial year

2 Targets pertain to the biodegradable fraction

3 Results from WasteDataFlow for 2005/6 http://www.defra.gov.uk/environment/statistics/wastats/bulletin.htm
4 The Landfill Directive, Waste and Emissions Trading Act 2003 and Landfill Allowances Trading Scheme Regulations 2004

2. How it works
This section comprises an overview of the
principles of Advanced Thermal Treatment
processes.
2.1 Advanced Thermal Treatment
Advanced Thermal Treatment technologies
are primarily those that employ pyrolysis
and/or gasification to process municipal solid
waste (MSW). It excludes incineration5 of
wastes which is already a mature and well
established technology.
The gasification and pyrolysis of solid materials
is not a new concept. It has been used
extensively to produce fuels such as charcoal,
coke and town or producer gas. Charcoal and
coke are produced by pyrolysing wood and
coal respectively and producer gas is a
combustible gas produced by the gasification
of coke in the presence of air and steam.
It is only in recent years that such pyrolysis and
gasification have been commercially applied to
the treatment of MSW. The development of
pyrolysis and gasification technologies is in its
infancy in the UK but large scale plants have
been built and are in operation in Europe,
North America and Japan.
2.2 Difference between Pyrolysis,
Gasification and Incineration
There are a variety of differences promoted
to differentiate Advanced Thermal Treatment
from traditional Incineration technologies.
One distinction is that smaller scale facilities
are being marketed for treatment of MSW
with some ATT processes than that typical of
incineration. It is the difference in scale and
size that can make it easier to find local
markets for both heat and electricity
produced. While incineration plants are
typically centralised operations, the modular

2. Main
How Heading
it works
design of ATT operations allows a greater
degree of flexibility in terms of location.
Sections 6 and 7 discuss planning and public
perception aspects of ATT and the process
differences are described below.
Established Thermal Treatment Incineration
Incineration usually involves the combustion
of unprepared (raw or residual) MSW. To
allow the combustion to take place a
sufficient quantity of oxygen is required to
fully oxidise the fuel. Typically, incineration
plant combustion (flame) temperatures are in
excess of 850C and the waste is converted
into carbon dioxide and water. Any noncombustible materials (e.g. metals, glass)
remain as a solid, known as Bottom Ash, that
contains a small amount of residual carbon.
Advanced Thermal Treatment - Pyrolysis
In contrast to combustion, pyrolysis is the
thermal degradation of a substance in the
absence of oxygen. This process requires an
external heat source to maintain the
temperature required. Typically, relatively
low temperatures of between 300C to 850C
are used during pyrolysis of materials such as
MSW. The products produced from
pyrolysing materials are a solid residue and a
synthetic gas (syngas). The solid residue
(sometimes described as a char) is a
combination of non-combustible materials
and carbon. The syngas is a mixture of gases
(combustible constituents include carbon
monoxide, hydrogen, methane and a broad
range of other VOCs). A proportion of these
can be condensed to produce oils, waxes and
tars. The syngas typically has a net calorific
value (NCV) of between 10 and 20 MJ/Nm3. If
required, the condensable fraction can be
collected by cooling the syngas, potentially
for use as a liquid fuel.

5 Incineration of MSW in the UK always involves some form of energy recovery, either in the form of electricity generation and/or heat

recovery. As such it is also commonly termed Energy from Waste. In this document we will refer to incineration to distinguish from
Advanced Thermal Treatment

2. How it works
Advanced Thermal Treatment - Gasification
Gasification can be seen as between pyrolysis
and combustion in that it involves the partial
oxidation of a substance. This means that
oxygen is added but the amounts are not
sufficient to allow the fuel to be completely
oxidised and full combustion to occur. The
temperatures employed are typically above
650C. The process is largely exothermic but
some heat may be required to initialise and
sustain the gasification process. The main
product is a syngas, which contains carbon
monoxide, hydrogen and methane. Typically,
the gas generated from gasification will have
a net calorific value (NCV) of 4 - 10 MJ/Nm3.
The other main product produced by
gasification is a solid residue of noncombustible materials (ash) which contains a
relatively low level of carbon. For reference,
the calorific value of syngas from pyrolysis
and gasification is far lower than natural gas,
which has a NCV of around 38 MJ/Nm3.

water on the environment and human health

resulting from the incineration and coincineration of waste. WID also covers the
combustion of syngas produced from ATT
processes treating MSW.
The key requirements in the WID for the
operation of a facility are:
A minimum combustion temperature and
residence time of the resulting combustion
products. For MSW this is a minimum
requirement of 850C for 2 seconds
Specific emission limits for the release to
atmosphere of the following:
-

Sulphur Dioxide (SO2)

Nitrogen Oxides (NOx)
Hydrogen Chloride (HCl)
Volatile Organic Compounds (VOCs)
Carbon Monoxide (CO)
Particulate (fly ash)
Heavy Metals
Dioxins

a requirement that the resulting bottom

ash that is produced has a total organic
carbon content of less than 3%.
2.4 ATT Technology Overview
The actual plant design and configuration of
ATT facilities will differ considerably between
technology providers. However, an ATT plant
will typically consist of the following key
elements:
2.3 Waste Incineration Directive (WID)
In the UK, all waste incineration plant and
ATT plant treating waste must comply with
the Waste Incineration Directive (WID). The
Directive sets the most stringent emissions
controls for any thermal processes regulated
in the European Union. The objectives of
WID are to minimise the impact from
emissions to air, soil, surface and ground
4

Waste reception, handling and pretreatment;

Thermal treatment reactor;
Gas and residue treatment plant (optional);
Energy recovery plant (optional); and
Emissions clean-up.
Figure 1 describes the generic process flows
for ATT technologies.

2. How it works
Figure 1: ATT generic process flows

Residual MSW

Electricity to National Grid

Heat to
Industrial
users

Limited Oxygen
Gasification
Process

Preparation to
produce refuse
derived fuel
(RDF)

Regulated
emissions

Syngas
Heat and Power
generation
Hydrogen
(if market
requirement)

Bottom Ash
Metals

Gas and emissions

cleaning

Absence of oxygen
Syngas
Pyrolysis
Process
Char for
industrial
user

Solids for
reuse,
recycling
or disposal

Water

Bottom Ash
Metals

2. How it works
Waste Reception, Handling and Pre-treatment
The pyrolysis and gasification process is
focused on treating the biodegradable based
materials present in MSW (e.g. paper,card,
putrescible waste, green waste, wood), as
well as plastics. Therefore, it is common to
remove non combustible materials and
recyclables, (typically metals and glass) prior
to the primary treatment reactor stage
(2.3.2). In addition, depending on the
technology employed, the feed material
might require processing to remove excess
moisture and shredding to reduce the size.
It is the preference (for most ATT processes) to
treat only pre-processed residual MSW that
makes these systems appropriate to be

integrated into a wider municipal waste

management strategy. ATT processes may be
used in conjunction with other waste
treatment technologies such as Mechanical
Biological Treatment (MBT) and Mechanical
Heat Treatment (MHT). Many MBT/MHT plant
are designed to produce a fuel stream
(primarily composed of paper, card and
plastics) as one of the outputs from the
process. This is commonly referred to as
Refuse Derived Fuel or RDF (see Box 1). This
may be more amenable to processing in an
ATT plant rather than raw MSW. ATT facilities
are identified as one of the 6 potential outlets
identified by Defra as suitable for RDF. For
more information on MBT, MHT and the
potential outlets for RDF see the separate
technology briefs in this series.

Box 1: Fuel from mixed waste processing operations

The current prevalent term used for a fuel
produced from combustible waste is Refuse
Derived Fuel (RDF). The types of technologies
used to prepare or segregate a fuel fraction
from MSW include the Mechanical Biological
Treatment (MBT) and Mechanical Heat
Treatment (MHT), described in separate
Technology Briefs in this series.
A CEN Technical Committee (TC 343) is currently
progressing standardisation work on fuels
prepared from wastes, classifying a Solid
Recovered Fuel (SRF). Preliminary standards have
been published in June 2006, and are following
an evaluation process, during which the
functioning of the specifications will be verified.
The technical specifications classify the SRF by
thermal value, chlorine content and mercury
content. For example, the thermal value class
will be based on the number of megajoules one
kilogram of recovered fuel contains. In addition,
there are many characteristics for which no
specific values have been determined. Instead,
they can be agreed upon between the producer
and the purchaser of SRF.

Along with the standardisation process, a

validation project called QUOVADIS
(http://quovadis.cesi.it/) on solid recovered fuels
is currently being implemented.
It is anticipated that once standards are
developed and become accepted by users, then
SRF will become the terminology used by the
waste management industry. Other terminology
has also been introduced to the industry as
various fuel compositions may be prepared from
waste by different processes. Examples include
Biodegradable Fuel Product (BFP) and Refined
Renewable Biomass Fuel (RRBF).
European standards for SRF are important for the
facilitation of trans-boundary shipments and
access to permits for the use of recovered fuels.
There may also be cost savings for co-incineration
plants as a result of reduced measurements (e.g.
for heavy metals) of incoming fuels. Standards
will aid the rationalisation of design criteria for
combustion units, and consequently cost savings
for equipment manufacturers. Importantly
standards will guarantee the quality of fuel for
energy producers.

2. How it works
Thermal Treatment Reactor
The thermal treatment process, whether
pyrolysis or gasification, will produce syngas
and solid residue. The composition of the
syngas and solid residue will depend on the
process conditions employed, which include
operating temperature, oxygen level, heating

Table 1:

rate and residence time in the reactor. The

main types of thermal treatment units
available, their application and operating
conditions are summarised in Table 1. There
are also other factors influencing the process
such as direction of gas flow (e.g. horizontally
or vertically).

Treatment Reactors

Reactor

Typical Application

Operating Conditions

Rotating Kiln

Pyrolysis

Typically operate at temperatures of between 300 850oC. Unit

can accommodate large size feed material (200 mm). Kiln is
heated externally and waste is fed in from one end of the kiln
which slowly rotates creating a tumbling action. This mixes the
waste and ensures contact with the heating surface and gases
inside the kiln.

Heated Tube

Pyrolysis

The tubes are heated externally and temperatures as high as

800oC are used. The process can accommodate large size feed
material. The waste passes through the tube at a set speed to
ensure the pyrolysis process is complete.

Surface Contact

Pyrolysis

Small size feed material required and therefore significant pretreatment is necessary. Process operates at high temperatures and
the small size of the feed gives high heating rates. The
application of this technology is to maximise the rate of pyrolysis.

Fluidised Bed

Gasification

Fluidised bed technology may be used for gasification or

combustion processes. The bed is a mass of particles (typically
alumina) that has similar characteristics to a moving fluid. This is
achieved by blowing hot gases through the bed of particles. This
system provides good mixing and heat transfer to the incoming
waste. Waste is pre-treated to remove large sized material. This
technology is well suited to the gasification of refuse derived
fuels.

Fixed Bed

Gasification

There are a range of different reactor types that come under this
heading. A typical example is a grate system where the feed
passes along the grate and hot gases pass through the bed of
waste heating it.

2. How it works
Gas and Residue Treatment Stages
Solids will inevitably be discharged from the
process. These solids include metals together
with carbon. In the case of gasification, the
level of carbon is small; in pyrolysis it is
significant. Larger particles of solids in the
thermal treatment reactor are usually
discharged as bottom ash and slag. Lighter
ash is usually collected when the gas is
separated with the use of cyclones and
ultimately filters. In addition, volatile metals
such as lead, tin, cadmium and mercury will
be carried in the gas until such point that the
gas is cooled for them to be sufficiently
condensed.
Pollution control strategies for ATT plants will
typically be on a smaller scale than for
incineration technologies, hence less costly,
due to the reduction in the volume of process
air required however compliance with the
Waste Incineration Directive would still be
mandatory.

would require cleaning and cooling prior to

use. However, using a gas engine or gas
turbine could increase efficiencies for
electricity generation. This is of particular
relevance if a Combined Cycle Gas Turbine
(CCGT) or Combined Heat and Power (CHP)
configuration is used (see table 2). Whilst
high efficiencies can be achieved using gas
engines, the highest efficiencies can only be
reached using a high calorific value gas.
Efficiencies should be checked if using a lower
calorific value gas.
To minimise costs for energy generation the
ATT plant could be located adjacent to an
existing power plant and the syngas
transferred to it. This would also provide
benefits if the existing plant has a higher
efficiency than a standalone unit. The power
plant may require upgrading to comply with
the Waste Incineration Directive, to improve
the abatement system for controlling
emissions from the combustion of the syngas,
which could incur additional costs.

Energy Recovery/Utilisation of Syngas

One of the potential benefits of pyrolysis and
gasification is that the syngas can be used in
a number of different ways.
In terms of producing energy, the most
common configuration is to burn the syngas
in a boiler to generate steam. The steam can
then be used to generate electricity by
passing it through a steam turbine and, if
there is a demand local to the plant, for
heating. Using the heat in addition to
generating electricity improves the overall
energy efficiency of the system significantly.
The syngas can also be used to fuel a
dedicated gas engine. A syngas from a very
well run gasifier, or further processed for
example by reforming, may be suitable for
use in a gas turbine. Running these types of
plant on syngas is still in its infancy and
8

In addition to using the syngas to produce

energy, it could also be used as a chemical
feedstock. This offers a further option for
utilising the syngas but would require the
treatment plant to be local to the end user, in
order to be a practical solution. This would

2. How it works
require very high gas cleanliness; pollutants,
notably sulphur and halogens, may need to be
removed prior to combustion of the gas. The
reduced gas volumes involved in cleaning the
combusted gas rather than the combustion gas
gives a financial advantage to the process.
Alkalis such as lime and sodium hydroxide are
the favoured reagents for removal of the
halogen streams. Sulphur can be removed by a
variety of routes, largely dependant on the
initial concentration (ranging from absorption
to the Klaus reaction).

and as a vehicle fuel. There are predicted

carbon dioxide reduction benefits of the
hydrogen from waste route, compared with
the current use of natural gas and electrolysis
to produce the gas. There would however be
significant purification and reforming
required before the gas would be of an
appropriate quality for power generation (in
turbines) or transport (in fuel cells)7.

For reference a summary of the potential net

electrical generating efficiencies for new
build thermal treatment plant employing
various energy recovery options is presented
in Table 2. For comparison the performance
of a new incinerator is also provided.
Significantly greater efficiencies are possible
by recovering useable heat as well as power.

The advantages of using ATT plants to

produce the syngas would arise from their
relatively small scale, flexibility to different
inputs and modular development. Producing
syngas to serve multiple end uses could
complicate delivery of the plants but it could
provide a higher degree of financial security
than building the entire business case around
customer. Although the national grid could
take all of the electricity output these prices
do fluctuate.

Table 2:

2.5 Examples of ATT technologies

Potential net electrical generating

efficiencies
Efficiencies of
Pyrolysis/
Gasification
Treatment Plant

Efficiencies
of
Incinerator

Steam Boiler and

Turbine

10% - 20%

14% - 27%6

Gas Engine

13% - 28%

n/a

Combined Cycle
Gas Turbine

30%

n/a

Co-firing in
existing power
plant

Up to 27%

n/a

Energy System

Syngas from waste has also been identified as

a potential source of hydrogen, which could
have applications in both power generation

Some descriptive examples of ATT processes

are included here to illustrate the different
technologies being promoted for MSW
management. The technical details of these
and other examples, including mass and
energy balances and an analysis of the
Strengths, Weaknesses, Opportunities and
Threats are included on the Waste
Technology Data Centre.
Waste Gen (Tech Trade) Hamm Germany
This is a pyrolysis plant that processes a preprepared RDF to produce a syngas that is
immediately burnt in a dedicated burner in
an otherwise coal fired power station boiler.
The resulting char after recovery of metals
using magnets and aggregate, using a

6 Typical incinerator efficiencies range from 14% to 24%. A recent report (Carbon Balances and Energy Impacts of the Management of UK

Wastes, ERM and Golder Associates report for Defra, March 2006 www.defra.gov.uk/science/project_data/DocumentLibrary/WR0602/
WR0602_4750_FRP.pdf) states an efficiency range for electricity only of between 20-27%
7 The Potential for Hydrogen Production from Waste in London; The London Hydrogen Partnership http://www.lhp.org.uk/content/images/
articles/LHPReportFinal3LR(1).pdf

2. How it works
ballistic separator, is fed into the station
coalbunkers. Fuel is delivered to the plant in
bales or bulk form, from a range of RDF
producers. The fuel is conveyed to the two
rotary kiln, pyrolyser, units (20m in length x
2.8m in diameter). Natural gas burners heat
the pyrolysis drums. The two pyrolysis drums
replace 10% of the fuel input to a coal fired
330Mwe generating set.
KBI Waste & Energy Solutions GmbH
This is a Mechanical & Biological Treatment
(MBT) plant followed by an oxygen blown
down draught gasifier. The purpose of the
waste pre-treatment and the gasifier is to
produce a gas of a quality and consistency
such that the power plant can safely and
reliably operate to a defined efficiency and
emission limits.
Received waste is dried in a rotating compost
drum and recyclates are removed. The waste
then passes to a feed preparation area where
additives such as coke, (typically 17%) and
limestone are introduced prior to gasification.
In the gasifier oxygen is added at several
points down the gasifier progressively raising
the temperature towards the maximum,
normally 1500C. Additional feeds of steam
and natural gas are used so as to control the
composition of the produced gas. The gas is
to be used for power generation via a gas
turbine set. The gas is burned in a
conventional gas turbine set and the exhaust
gas from the turbine is used to raise steam.
Some of the steam / electricity is used by the
process with the excess available for export.
GEM, Graveson Energy Management, Port
Talbot, UK
This process uses fast pyrolysis of a Refuse
Derived Fuel (RDF see box 1) to produce a gas
suitable for burning or powering an engine.
10

The essential principle behind the process is

to rapidly heat the feed to around 820oC, in
the absence of oxygen and hence induce
rapid pyrolysis. To do this conventional RDF
has to be ground such that one major
dimension of each RDF particle is less than
2mm. The ground floc then has to be dried
to 5% moisture prior to feeding into the
pyrolyser. The Pyrolyser consists of a large
vertical steel cylinder heated on its outside
surface. A close fitting cylindrical drum is
suspended and rotated within this cylinder.
The RDF is fed at the top of the cylinder and
by falling through the gap between the
cylinder and drum is rapidly heated. Within a
couple of seconds the RDF has been
pyrolysed. Char is separated from the gas in
a cyclone. The gas stream is cooled and
scrubbed to remove acid gases. The cleaned
gas is then fed to a spark ignition engine
generator set. Waste heat from the pyrolyser
heater, the engine exhaust, engine cooling
and the produced gas cooler is collected and
integrated with the local heat requirements
which may be parasitic loads or potentially
offsite heat demands, hence giving a
combined heat and power system.
2.6 Summary
This section explains that Advanced Thermal
Treatment processes are primarily pyrolysis
and/or gasification based. ATT are capital
intensive facilities and have a design life of 15
25 years. Rigorous evaluation of the
technology is essential to reduce any
operational risks when processing the
anticipated feedstock. Over this timescale the
composition of waste is likely to alter and the
process selected should be robust or flexible
enough to treat varying calorific values and
compositions of waste feedstock.

3. Markets and outlets for the outputs

ATT processes will all produce a gas (usually
for energy recovery) and a solid residue (slag,
ash or char). Some facilities are also designed
with mechanical preparation and sorting
equipment to extract recyclables. Table 3
summarises the key outputs from ATT
processes and the following sections address
materials and energy recovery.
Table 3:

Examples of outputs from ATT

processes

Outputs

State

Potential Markets

Slag (from
Solid, fused
gasification)

Aggregate

Ash (from
Un-fused residue
gasification)

Aggregate
replacement,
metals can be
separated

Flue Gas
Treatment
residue

Solid, powder/
sludge. Invariably
a hazardous
waste; some
potential for
neutralising waste
acids

Specialist Disposal
or treatment
potential use in
Chemical
treatment works
(e.g. neutralising
acid waste)

Syngas

Gaseous

Heat or power
generation/fuel/
some chemical
application

Condensate

Liquid

Fuel/chemical
application. Care
needs to be taken
with the chemical
composition of this
and the hazards
associated with it

Char (from
pyrolysis)

Solid

Hazardous waste
but could be used
as coal
replacement in
certain combustion
applications or as a
gasifier feedstock

The following section summarises some key

issues with regard to these outputs.
3.1 Recovery from ATT
Materials Recycling
Recyclables derived from either the front end
preparation stage of an ATT plant or metals
extracted from the back end of the process
(i.e. out of the ash) are typically of a lower
quality than those derived from a separate
household recyclate collection system, and
generally have a lower value accordingly. The
types of materials recovered from ATT
processes almost always include metals
(ferrous and non-ferrous), usually from the
front end of the process. Metal removal can
help enhance overall recycling levels and
enable recovery of certain constituent parts
that would not otherwise be collected in
household systems (e.g. steel coat hangers,
scrap metal etc.).
Pyrolysis plants produce a bottom residue
that contains significant amounts of carbon.
This will need to be disposed of to landfill, or
treated further to reduce the carbon content
for example by gasification or combustion. If
treated further the final bottom residue could
then be recycled as a secondary aggregate.
Gasification tends to produce a bottom
residue which has a lower carbon content and
has usually been melted or fused, and this
could therefore be recycled as aggregate.
The recycling of bottom ash would need to
be undertaken in accordance with relevant
legislation but is likely to be of equivalent or
potentially better quality than incinerator
bottom ash, which is currently recycled in
aggregate applications.

11

3. Markets and outlets for the outputs

For more information on the contribution of
ATT to Best Value Performance Indicators and
recycling see section 9, and for the latest
developments see the local authority
performance pages on the Defra website
http://www.defra.gov.uk/environment/waste/l
ocalauth/perform-manage/index.htm and
http://www.wastedataflow.org/Documents/BV
PI%20FAQs.pdf. The Defra New Technologies
Demonstrator also includes ATT facilities,
more information on which is available
through the Defra website or from
Wastetech@enviros.com.
Energy Recovery
ATT processes are designed to recover energy
from the waste processed either in the form
of fuel production (liquid or gas) or
combusting the syngas to generate electricity
and/or heat for use on site and export off
site. There is also potential for the syngas to
be utilised in vehicles, after reforming to
produce hydrogen. It is envisaged that the
initial market for the hydrogen would be
public transport fleets using fuel cell vehicles.

12

Examples of energy recovery from case

studies are included on the Waste Technology
Data Centre. Electricity generated from the
biomass fraction of waste in gasification and
pyrolysis plants is eligible for support under
the Renewables Obligation.
It should be noted that the processes using
RDF will have already incurred energy usage
in the preparation of the fuel and this
prepared material will have a higher calorific
value than raw MSW.

4. Track record
Whilst ATT technologies are established
technologies for the treatment of certain
specific waste streams, it is only in recent years
that pyrolysis and gasification have been
commercially applied to the treatment of MSW.
The prime drivers in the UK for the
development of these technologies are
increasing landfill costs and the
Table 4:

implementation of the Landfill Directive. The

development of pyrolysis and gasification
technologies for MSW is in its infancy in the
UK but commercial scale plant have been built
and are in operation in Europe, North America
and Japan. Table 4 provides examples of ATT
facilities in the UK and overseas, treating MSW
and other types of waste.

ATT facilities

Manufacturer

Primary Technology

Country

Operational

Capacity, tpa

Feed

UK - Avonmouth

2001

8,000

Clinical Waste

Compact Power

Tube Pyrolysis

Energos

Grate Gasification

Norway

1997

10,000

Industrial & Paper Wastes

Energos

Grate Gasification

Norway

2000

34,000

MSW

Energos

Grate Gasification

Norway

2001

36,000

MSW & industrial waste

Energos

Grate Gasification

Norway

2002

70,000

MSW & industrial waste

Energos

Grate Gasification

Norway

2002

37,000

MSW

Energos

Grate Gasification

Germany

2002

37,000

MSW & industrial waste

Energos

Grate Gasification

Germany

2005

80,000

MSW, Commercial, Industrial

Energos

Grate Gasification

Sweden

2005

80,000

Municipal & Industrial Waste

Spain

2002

25,000

Plastics

USA

1997

165,000

Biomass

Finland

1998

80,000

Mix waste

Enerkem/Novera Fluidised Bed Gasification

FERCO

Fluidised Bed Gasification

Foster Wheeler

Fast (ablative) Pyrolysis

Mitsui Babcock

Rotary Kiln Pyrolysis

Japan

2000

80,000

MSW

Mitsui Babcock

Rotary Kiln Pyrolysis

Japan

2002

150,000

MSW

Mitsui Babcock

Rotary Kiln Pyrolysis

Japan

2002

50,000

MSW

Mitsui Babcock

Rotary Kiln Pyrolysis

Japan

2003

95,000

MSW

Mitsui Babcock

Rotary Kiln Pyrolysis

Japan

2003

75,000

MSW

Mitsui Babcock

Rotary Kiln Pyrolysis

Japan

2003

60,000

MSW

Thermoselect

Tube Pyrolysis

Germany

1999

225,000

Domestic & Industrial Wastes

Thermoselect

Tube Pyrolysis

Japan

1999

100,000

Domestic & Industrial Wastes

Thermoselect

Tube Pyrolysis

Japan

2003

50,000

Industrial Wastes

Techtrade/
Wastegen

Rotary Kiln Pyrolysis

Germany

1984

35,000

RDF

Techtrade/
Wastegen

Rotary Kiln Pyrolysis

Germany

2002

100,000

Domestic & Industrial Wastes

13

4. Track record
The following case studies detail ATT plants under development as demonstration sites under the
Defra New Technologies Demonstrator Programme. For more information see
http://www.defra.gov.uk/environment/waste/wip/newtech/dem-programme/index.htm or contact
wastetech@enviros.com.

Compact Power Avonmouth, Bristol

Compact Power - The Avonmouth Renewable
Energy Plant, Bristol
Advanced thermal conversion technology
combines pyrolysis, gasification and high
temperature oxidation
2 tube modular process with each unit
processing up to 500 kg per hour tph of
non-recyclable waste
Capacity of approximately 24,000 tpa of MSW,

Proposed facility

Energy outputs from the process will be

2,400 kW of electricity and 7,620 kW of heat
Collaboration with Bristol City Council, due to be commissioned and in operation
by mid 2008.

Energos - Isle of Wight

Gasification facility will be integrated with existing
MRF and in-vessel composting facilities to process
residual MSW, in the form of RDF
Capacity of 30,000 tpa RDF plant
Consumes RDF with a high biodegradable content
(70 - 80%) and a calorific value of 11 14 MJ/kg
Will export approximately 1.8 MWe of renewable
electricity and locally useable waste heat.

14

Example of Energos
gasification site

4. Track record

Novera Energy Havering, Essex

Novera is a renewable energy company working in partnership with East London Waste
Authority (ELWA) and Ford Motor Company
The gasification plant is designed to process 70 - 90,000 tpa RDF from a near by
Mechanical Biological Treatment (MBT) plant treating waste from ELWA
Will provide between 8-10 MW of energy and heat to Ford plant at Dagenham
(Equivalent to approximately 4 million per annum worth of electricity purchased from
the National Grid. ELWA will benefit through having a LATS surplus
The RDF will be of low moisture content (~13%) hence have a relatively high calorific
value of around 17 MJ/kg
This demonstrator is conceptually
different the other projects. If
successful it will showcase the
possible relationships which can be
built between high energy
consumers in industry, the waste
industry and local authorities.

Artists impression of the facility

Yorwaste - Seamer Carr, North Yorkshire

The site will utilise 12,000 tpa of RDF from a complex Materials Recycling Facility sorting
MSW
The RDF will have an approximate calorific value of
15 MJ/kg.
It will produce 2.4 MWe of renewable electricity
and locally useable waste heat
The pyrolysis facility will be integrated with an
existing MRF and in-vessel composting facilities to
process MSW
Planning Permission was approved in April 2007
and a PPC Permit application submitted to the
Environment Agency in March 2007

Yorwaste processing equipment

15

5. Contractual and financing issues

5.1 Grants & Funding

5.2 Contractual Arrangements

Development of ATT plant will involve capital

expenditure of several million pounds. There
are a number of potential funding sources for
Local Authorities planning to develop such
facilities, including:

Medium and large scale municipal waste

management contracts, since January 2007,
are procured through EU Competitive
Dialogue (CD). This is dialogue between an
authority and the bidders with the aim of
developing a suitable technical or legal
position against which all the bidders can
submit a formal bid. More information on
CD is available from the 4ps website.

Capital Grants: general grants may be

available from national economic initiatives
and EU structural funds;
Prudential Borrowing: the Local
Government Act 2003 provides for a new
'prudential' system of capital finance controls;
PFI Credits and Private Sector Financing:
under the Private Finance Initiative a waste
authority can obtain an annual subsidy from
central government through a Special Grant;

The contractual arrangement between the

private sector provider (PSP) and the waste
disposal authority (or partnership) may be
one of the following:

Other Private-Sector Financing: A

contractor may be willing to enter into a
contract to provide a new facility and operate
it. The contractors charges for this may be
expressed as gate fees; and

Separate Design; Build; Operate; and

Finance: The waste authority contracts
separately for the works and services needed,
and provides funding by raising capital for
each of the main contracts. The contract to
build the facility would be based on the
councils design and specification and the
council would own the facility once
constructed;

Other Existing sources of local authority

funding: for example National Non-Domestic
Rate payments (distributed by central
government), credit (borrowing) approvals,
local tax raising powers (council tax), income
from rents, fees, charges and asset sales
(capital receipts). In practice capacity for this
will be limited but generally it is through
raising taxes.

Design & Build; Operate; Finance: A

contract is let for the private sector to
provide both the design and construction of a
facility to specified performance
requirements. The Council owns the facility
that is constructed and makes separate
arrangements to raise capital. Operation
would be arranged through a separate
Operation and Maintenance contract;

The Government is encouraging the use of

different funding streams, otherwise know as
a mixed economy for the financing and
procuring of new waste infrastructure to
reflect the varying needs of local authorities.

Design, Build and Operate; Finance: The

Design and Build and Operation and
Maintenance contracts are combined. The
waste authority owns the facility once
constructed and makes separate
arrangements to raise capital;

16

5. Contractual and financing issues

Design, Build, Finance and Operate
(DBFO): This contract is a Design, Build and
Operate Contract but the contractor also
provides the financing of the project. The
contractor designs, constructs and operates
the plant to specified performance
requirements. Regular performance
payments are made over a fixed term to
recover capital and financing costs, operating
and maintenance expenses, plus a reasonable
return. At the end of the contract, the facility
is usually transferred back to the client in a
specified condition; and
DBFO with PFI: This is a Design, Build,
Finance and Operate contract, but it is
procured under the Private Finance Initiative.
In this case the waste authority obtains
funding for future payment obligations from
Government as a supplement to finance from
its own and private sector sources.
The majority of large scale waste
management contracts currently being
procured in England are Design, Build,
Finance and Operate contracts. Many waste
disposal authorities in two tier English
arrangements (County Councils) seek to
partner with their Waste Collection
Authorities (usually District or Borough
Councils). Sometimes partnerships are also
formed with neighbouring Unitary
Authorities to maximise the efficiency of the
waste management service and make the
contract more attractive to the Private Sector
Provider.

planning status; interface with existing

contracts; timescales; governance and decision
making arrangements; market appetite and
risk allocation.
Further guidance on these issues can be
obtained from:
Local Authority funding
http://www.defra.gov.uk/environment/wast
e/localauth/funding/pfi/index.htm
The Local Government PFI project support
guide www.local.odpm.gov.uk/
pfi/grantcond.pdf
For Works Contracts: the Institution of Civil
Engineers New Engineering Contract
(available at www.ice.org.uk).
For large scale Waste Services Contracts
through PFI and guidance on waste sector
projects see the 4ps, local government's
project delivery organisation http://www.
4ps.gov.uk/PageContent.aspx?id=90&tp=Y

Before initiating any procurement or funding

process for a new waste management
treatment facility, the following issues should
be considered: performance requirements;
waste inputs; project duration; project cost;
available budgets; availability of sites;

17

6. Planning and permitting issues

This section contains information on the
planning and regulatory issues associated
with ATT facilities based on legislative
requirements, formal guidance, good practice
and in particular drawing on information
contained in the Office of the Deputy Prime
Ministers research report on waste planning
published in August 20048.
6.1 Planning Application Requirements
All development activities are covered by
Planning laws and regulations. Minor
development may be allowed under Permitted
Development rights but in almost all cases new
development proposals for waste facilities will
require planning permission.
Under certain circumstances new waste
facilities can be developed on sites previously
used for General Industrial (B2) or Storage
and Distribution (B8) activities. In practice
even where existing buildings are to be used
to accommodate new waste processes,
variations to existing permissions are likely to
be required to reflect changes in traffic
movements, emissions etc.
Under changes to the planning system
introduced in 2006 all waste development is
now classed as Major Development. This has
implications with respect to the level of
information that the planning authority will
expect to accompany the application and also
with respect to the likely planning
determination period. The target
determination periods for different
applications are:

The principal national planning policy

objectives associated with waste management
activities are set out in Planning Policy
Statement (PPS) 10 Planning for Sustainable
Waste Management published in July 2005.
Supplementary guidance is also contained
within the Companion Guide to PPS 109. Both
of these documents can be accessed via the
Department of Communities and Local
Government (DCLG) website .
PPS 10 places the emphasis on the plan led
system which should facilitate the
development of new waste facilities through
the identification of sites and policies in the
relevant local development plan. Separate
guidance on the content and validation of
planning applications is also available from
DCLG through their website10. Individual
Planning Authorities can set out their own
requirements with respect to supporting
information and design criteria through
Supplementary Planning Documents linked to
the Local Development Framework. It is
important that prospective developers liaise
closely with their Local Planning Authorities
over the content and scope of planning
applications.

Standard Application 8 weeks

Major Development - 13 weeks
EIA Development - 16 weeks
8 http://www.communities.gov.uk/embeddedindex.asp?id=1145711
9 http://www.communities.gov.uk/index.asp?id=1143834
10 http://www.communities.gov.uk/pub/494/BestPracticeGuidanceontheValidationofPlanningApplicationsPDF326Kb_id1144494.pdf

18

6. Planning and permitting issues

6.2 Key Issues
When considering the planning implications
of an ATT facility the key issues that will need
to be considered are common to most waste
management facilities and are:
Plant/Facility Siting;
Traffic;
Air Emissions / Health Effects;
Dust / Odour;
Flies, Vermin and Birds;
Noise;
Litter;
Water Resources;
Visual Intrusion; and

The location of such plants together with

facilities producing RDF (such as MBT and
MHT facilities) could be advantageous. The
potential for co-location of such facilities
on resource recovery parks or similar is also
highlighted in the Companion Guide; and
The potential for export of energy to host
users or the national grid should also be a
key consideration in the siting of ATT
facilities. The Renewables Obligation
provides a price premium for electricity
generated from renewable sources (the
biomass fraction of waste) in gasification
and pyrolysis plants Consideration should
always be given to utilising not only the
electricity from the plant but also the
waste heat in order to maximise energy
and carbon benefits.

Public Concern
6.4 Traffic
A brief overview of the planning context for
each of these issues is provided below.
6.3 Plant Siting
PPS 10 and its Companion Guide contain
general guidance on the selection of sites
suitable for waste facilities. This guidance
does not differentiate between facility types,
however the following criteria are likely to
apply to the siting of new ATT facilities:

ATT facilities may be served by large numbers

of HGVs (depending on the scale of the
facility) with a potential impact on local roads
and the amenity of local residents. It is likely
that the site layout/road configuration will
need to be suitable to accept a range of light
and heavy vehicles. For a 50,000tpa capacity
plant, up to 20 Refuse Collection Vehicles per
day would be anticipated.
6.5 Air Emissions/Health Effects

ATT processes can be similar in appearance

and characteristics to various process
industries. It would often be suitable to
locate facilities on land previously used for
general industrial activities or land
allocated in development plans for such
(B2) uses;
Facilities are likely to require good
transport infrastructure. Such sites should
either be located close to the primary road
network or alternatively have the potential
to be accessed by rail or barge;

In terms of complying with the Waste

Incineration Directive (WID) the major
emission from a plant with energy recovery is
the release of flue gases from the combustion
of the syngas (and in some instances also the
residual solid, if it has high carbon content).
The clean-up required for the flue gases is
dependent on the process from which they
have been generated. One of the main
benefits claimed by manufacturers for
pyrolysis and gasification plant is that
emissions of pollutants are lower than those
19

6. Planning and permitting issues

from conventional incineration and that plant
are designed to comply with the emission
limits set out in the directive.
Entrained (fine) particles in the syngas can
either be removed before or after
combustion depending on the treatment
process and combustion technology
employed.
A further solid residue that is produced is
from abatement plant used to clean-up the
flue gases from the combustion process. Both
of these solid streams are hazardous in
nature and must be disposed of
appropriately. Often they are combined as
they are removed during the same stage of
the flue gas clean-up.

enclosed in buildings. However, during hot

weather it is possible that flies could
accumulate, especially if they have been
brought in during delivery of the waste.
Effective housekeeping and on site
management of tipping and storage areas is
essential to minimise the risk from vermin
and other pests. In some operations waste
heat from the process may be used to bring
temperatures in fresh input waste to levels
above which flies can live. The use of RDF as a
feedstock would reduce this issue relative to
raw waste.

An independent study on Health &

Environmental impacts of waste management
processes found no evidence of health effects
linked to ATT facilities, although due to the
emergent nature of these technologies the
available data was only of a moderate
quality11.
6.8 Noise
6.6 Dust / Odour
Any waste management operations can give
rise to dust and odours. These can be
minimised by good building design,
performing all operations under controlled
conditions indoors, good working practices
and effective management undertaken for
dust suppression from vehicle movements.
Many ATT processes are designed to operate
under negative pressure within buildings to
minimise dust and odour problems.

Noise is an issue that will be controlled under

the waste licensing regulations and noise
levels received at nearby receptors can be
limited by a condition of a planning
permission. The main contributors to noise
associated with ATT are likely to be:
vehicle movements / manoeuvring;
traffic noise on the local road networks;
mechanical processing such as waste
preparation;

6.7 Flies, Vermin and Birds

air extraction fans and ventilation systems;

ATT processing is unlikely to attract vermin

and birds due to majority of waste
throughput and operations being completely

steam turbine units; and

11 http://www.defra.gov.uk/environment/waste/research/health/index.htm

20

air cooled condenser units.

6. Planning and permitting issues

6.9 Litter

6.12 Size and Land take

Any waste which contains plastics and paper

is more likely to lead to litter problems. With
ATT litter problems can be minimised as long
as good working practices are adhered to and
vehicles use covers and reception and
processing are undertaken indoors.

Table 5 shows the land area required for the

building footprint and also for the entire site
(including supporting site infrastructure) for
examples of thermal processes.

6.10 Water Resources

Water will be used but this will be specific to
the technology and therefore it is not
possible to provide detail on the nature of
the effluent that might be generated and
how it should be managed. However, as part
of the permitting requirements for a facility a
management plan would be required for
effluent. The case studies on the Waste
Technology Data Centre include an
assessment of water usage.

Table 5:

Landtake

TT Facility

Size,
tonnes
per
annum

Incineration*

90,000

5850

1.7

65m

Incineration*

250,000

6,600

70m

Pyrolysis

60,000

0.98

Pyrolysis

12,500

200

Plus
access
area

Pyrolysis

35,000

28,000
32,000

General
ATT*

50,000

3,600

1-2

30 70m

6.11 Visual Intrusion

Construction of any building will have an
effect on the visual landscape of an area.
Visual intrusion issues should be dealt with on
a site specific basis and the following items
should be considered:
Direct effect on landscape by removal of
items such as trees or undertaking major
earthworks;
Site setting; is the site close to listed
buildings, conservation areas or sensitive
viewpoints;
Existing large buildings and structures in
the area;
The potential of a stack associated with
some air clean up systems for mixed waste
processing operations may impact on visual
intrusion;
Use of screening features (trees, hedges,
banks etc); and

Buildings
Total
Area
Landtake
m2
Ha

Indicative
Stack
Height

Source:
* = Planning for Waste Management Facilities A
Research Study
= Waste Technology Data Centre.

ATT plants are expected to be of modular

design and scalable to suit the requirements
of different waste management operators.
For more information on Landtake for specific
waste management operations, see the Waste
Technology Data Centre.
6.13 Public Concern
Section 7, Social and Perception Issues, relates
to public concern. In general public concerns
about waste facilities relate to amenity issues
(odour, dust, noise, traffic, litter etc). With
thermal based facilities health concerns can
also be a perceived issue.

The number of vehicles accessing the site

and their frequency.
21

6. Planning and permitting issues

6.14 Environmental Impact Assessment
It is likely that an Environmental Impact
Assessment (EIA) will be required for an ATT
facility as part of the planning process.
Whether a development requires a statutory
EIA is defined under the Town and Country
Planning (Environmental Impact
Assessment)(England and Wales) Regulations
1999. The existing additional guidance in the
DETR circular 02/99 is currently being revised.
This new guidance is likely to focus on
appropriate criteria for establishing need for
EIA and not relate to the general nature of
proposals.
For more information on Planning issues
associated with waste management options
see Planning for Waste Management Facilities
A Research Study. Office of the Deputy
Prime Minister, 2004.
http://www.communities.gov.uk/pub/713/Plan
ningforWasteManagementFacilitiesAResearch
Study_id1145713.pdf
6.15 Licensing/Permitting
Currently, the interpretation of all ATT
operations is that they require a Pollution
Prevention & Control (PPC) permit. It would
be prudent to assume that any facilities will
be covered by the PPC Regulations. The
Environmental Permitting Programme (EPP) is
due to be implemented in April 2008 which
will combine waste licensing and permitting
systems. For more information on licensing &
permitting see http://www.environmentagency.gov.uk/subjects/waste/?lang=_e

22

7. Social and perception issues

This section contains a discussion of the social
and environmental considerations of ATT
facilities.
7.1 Social Considerations
Any new facility is likely to impact on local
residents and may result in both positive and
negative impacts. Potential impacts on local
amenity (odour, noise, dust, landscape) are
important considerations when siting any
waste management facility. These issues are
examined in more detail in the Planning &
Permitting section of this Brief. Transport
impacts associated with the delivery of waste
and onward transport of process outputs may
lead to impacts on the local road network.
The Planning and Permitting section of this
Brief provides an estimate of potential vehicle
movements.
An ATT facility may also provide positive
social impacts in the form of employment,
educational opportunities and a source of
low cost heat. Typical employment for a ATT
plant of 50,000tpa capacity would be 2-6
workers per shift. The plant would operate
on a shift system, to allow for 24-hour
operations. These facilities are also likely to
provide vocational training for staff. New
facilities may be built with a visitor centre to
enable local groups to view the facility and
learn more about how it operates.
7.2 Public Perception
Public opinion on waste management issues is
wide ranging, and can often be at extreme
ends of the scale. Typically, the most
positively viewed waste management options
for MSW are recycling and composting.
However, this is not necessarily reflected in
local attitudes towards the infrastructure
commonly required to process waste to
compost, or sort mixed recyclables. It should
be recognised that there is always likely to be

some resistance to any waste management

facility within a locality.
At present there is a relatively low level of
understanding of the concept of ATT by the
public. There are no full scale commercial ATT
operations in the UK processing MSW. In
public consultations these technologies score
inconsistently when explained in detail as a
residual waste treatment technology. There is
a general distrust of thermal systems in the
UK, however some ATT providers accentuate
the differences of their systems from
incineration as a key part of the promotion of
their technology.
Overseas development of Advanced Thermal
Treatment again shows inconsistencies. In
Australia developments of ATT plant received
similar perceptions to that of incineration,
partly due to campaigns from national
environmental groups claiming parallels
between the technologies. The national
environment campaign organisations in the
UK are divided on this issue. The public has
yet to be tested in the UK on ATT.
Overall, experience in developing waste
management strategies has highlighted the
importance of proactive communication with
the public over waste management options.
The use of realistic and appropriate models,
virtual walk throughs / artists impressions
should be used to accurately inform the
public. Good practice in terms of public
consultation and engagement is an important
aspect in gaining acceptance for planning
and developing waste management
infrastructure. Defra is funding the
development of small to medium scale
demonstration plant in England for local
authorities to visit and for Defra to publish
data on performance. For more information
see the Defra website or contact
Wastetech@enviros.com.
23

8. Cost
ATT plant have been applied to chemical and
process industries; these have all been large
scale, capital intensive applications.
The capital costs for an ATT facility will be
dependent on the quality of waste to be
processed, the technology employed and its
location. Costs will not only comprise those
associated with the purchase of the ATT
plant, but also costs for land procurement
and preparation prior to build and also
indirect costs, such as planning, permitting,
contractual support and technical and
financial services over the development cycle.
Capital costs provided by ATT technology
suppliers to the Waste Technology Data
Centre are wide ranging. Examples of capital
costs are list below:
9 million for a 25,000 tpa facility
12 million for a 40,000 tpa facility
19 million for a 80,000 tpa facility
17 million for a 100,000 tpa facility
50 million for a 60,000 tpa facility
Extreme care is required in utilising cost data
such as that provided on the data centre
website as it might not be fully inclusive. In
addition, site specific criteria need to be
taken into account, which are summarised
above and actual costs will vary on a case by
case basis.

24

9. Contribution to national targets

9.1 Recycling
Recyclate derived from an ATT plant
processing household waste qualifies for BVPI
82a (Recycling) for any materials recovered
prior to the thermal treatment reactor. Any
materials recovered after the thermal
treatment (e.g. metals from the ash), do not
count towards BVPI 82a. Equally any slag,
char or ash recycled does not count towards
BVPI 82a.
The material must pass to the reprocessor
(and not be rejected for quality reasons) to
count as recycling. It should be noted that
materials are extracted from the front end of
the process for recycling are likely to be of a
lower quality that source segregated
recyclables and therefore may experience
market limitations.
The Government has recently increased
national recycling and composting targets for
household waste through the Waste Strategy
for England 2007. Targets are at least 40% by
2010, 45% by 2015 and 50% by 2020. For
more information on the contribution of
incineration to Best Value Performance
Indicators and recycling see the local
authority performance pages on the Defra
website http://www.defra.gov.uk/
environment/waste/localauth/performmanage/index.htm and http://www.wastedata
flow.org/Documents/BVPI%20FAQs.pdf
9.2 Landfill Allowance Trading Scheme
(LATS)
The European Landfill Directive and the UKs
enabling act, the Waste & Emissions Trading
Act 2003, require the diversion of
biodegradable municipal waste (BMW) from
landfill. Incineration systems will divert 100%
of the BMW passing through the thermal
process from landfill as the output (char or
ash) will not be classified as biodegradable
even if disposed to landfill. Up to date

information can be obtained from Defras

LATS information webpage:
http://www.defra.gov.uk/environment/waste/l
ocalauth/lats/index.htm
9.3 Recovery
ATT technologies will contribute towards
recovery targets on the tonnage of materials
entering the thermal treatment process as all
processes are designed to recovery energy.
The Government has recently increased
national recovery targets for municipal waste
through the Waste Strategy for England 2007.
Targets are 53% by 2010, 67% by 2015 and
75% by 2020. For more information see the
Defra website and the guidance on BVPI 82c
http://www.defra.gov.uk/environment/waste/l
ocalauth/perform-manage/index.htm.
9.4 Renewable Energy
The Renewables Obligation (RO) was
introduced in 2002 to promote the
development of electricity generated from
renewable sources of energy. The Obligation
requires licensed electricity suppliers to source
a specific and annually increasing percentage
of the electricity they supply from renewable
sources, demonstrated by Renewables
Obligation Certificates (ROCs). The target
currently rises to 15.4% by 2015/16. In
essence, the RO provides a significant boost
to the market price of renewable electricity
generated in eligible technologies.
Electricity generated from the biomass
(renewable) fraction of waste in ATT is
eligible for support under the RO. This can
provide an important additional revenue
stream for a proposed plant, as long as it
meets the qualifying requirements. As the
value of a ROC is not fixed, the long term
value would need to be assessed in detail to
determine its overall financial value to the
project.
25

9. Contribution to national targets

The Department for Trade and Industry is
considering providing greater support to
technologies producing renewable energy
and assessment methods for removing
barriers to renewable energy generation. Upto-date information regarding ROCs can be
obtained from the DTI website
http://www.dti.gov.uk/energy/sources/renewa
bles/index.htlm.

26

10. Further reading and sources of

information
WRATE (Waste and Resources Assessment Tool for the Environment)
http://www.environment-agency.gov.uk/wtd/1396237/?version=1&lang=_e
The Waste Technology Data Centre www.environment-agency.gov.uk/wtd
New Technologies Demonstrator Programme Wastetech@enviros.com
Defra New Technologies website, http://www.defra.gov.uk/environment/waste/wip/newtech/index.htm
Integrated Pollution Prevention and Control, Draft Reference Document on Best Available
Techniques for the Waste Treatments Industries, European Commission Directorate General
Joint Research Centre, January 2004
Energy from Waste A Good Practice Guide, Energy from Waste working group, CIWM, 2003
Refuse Derived Fuel, Current Practice and Perspectives (B4-3040/2000/306517/Mar/E3), European
Commission Directorate General Environment, July 2003
Review of Environmental & Health Effects of Waste Management, Enviros Consulting Ltd,
University of Birmingham, Open University & Maggie Thurgood. Defra 2004.
AiIE Ltd, 2003, Review of residual waste treatment technologies, Report prepared on behalf of
Kingston upon Hull City Council and East Riding of Yorkshire Council
http/www.eastriding.gov.uk/environment/pdf/waste_treatment_technologies.pdf
The Additional Paper to the Strategy Unit, Waste Not Want Not study, Delivering the Landfill
Directive: The Role of New & Emerging Technologies, Dr Stuart McLanaghan
http://www.number10.gov.uk/files/pdf/technologies-landfill.pdf
Planning for Waste Management Facilities A Research Study. Office of the Deputy Prime
Minister, 2004.
http://www.communities.gov.uk/pub/713/PlanningforWasteManagementFacilitiesAResearch
Study_id1145713.pdf
Local Authority funding
http://www.defra.gov.uk/environment/waste/localauth/funding/pfi/index.htm
The Local Government PFI project support guide www.local.odpm.gov.uk/pfi/grantcond.pdf
For Works Contracts: the Institution of Civil Engineers New Engineering Contract (available at
www.ice.org.uk).
For large scale Waste Services Contracts through PFI and guidance on waste sector projects see
the 4ps, local government's project delivery organisation
http://www.4ps.gov.uk/PageContent.aspx?id=90&tp=Y
27

11. Glossary

Advanced Thermal
Treatment (ATT)

Waste management processes involving medium and high temperatures to recover

energy from the waste. Primarily pyrolysis and gasification based processes,
excludes incineration.

Aerobic

In the presence of oxygen.

Biodegradable

Capable of being degraded by plants and animals.

Biodegradable Municipal
Waste (BMW)

The component of Municipal Solid Waste capable of being degraded by plants and
animals. Biodegradable Municipal Waste includes paper and card, food and garden
waste, wood and a proportion of other wastes, such as textiles.

Co-combustion

Combustion of wastes as a fuel in an industrial or other (non waste management)

process.

Feedstock

Raw material required for a process.

Floc

A small loosely aggregated mass of flocculent material. In this instance referring to

Refuse Derived Fuel or similar.

Gasification

Gasification is the process whereby carbon based wastes are heated in the presence
of air or steam to produce a solid, low in carbon and a gas. The technology is based
on the reforming process used to produce town gas from coal.

Greenhouse Gas

A term given to those gas compounds in the atmosphere that reflect heat back
toward earth rather than letting it escape freely into space. Several gases are
involved, including carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O),
ozone, water vapour and some of the chlorofluorocarbons.

Green Waste

Waste vegetation and plant matter from household gardens, local authority parks
and gardens and commercial landscaped gardens.

Incineration

The controlled thermal treatment of waste by burning, either to reduce its volume
or toxicity. Energy recovery from incineration can be made by utilising the calorific
value of the waste to produce heat and / or power.

Materials Recycling
Facility/Materials Recovery
Facility (MRF)

Dedicated facility for the sorting / separation of recyclable materials.

Mechanical Biological
Treatment (MBT)

A generic term for mechanical sorting / separation technologies used in conjunction

with biological treatment processes, such as composting.

Municipal Solid Waste

(MSW)

Household waste and any other wastes collected by the Waste Collection Authority,
or its agents, such as municipal parks and gardens waste, beach cleansing waste,
commercial or industrial waste, and waste resulting from the clearance of fly-tipped
materials.

Pyrolysis

During Pyrolysis organic waste is heated in the absence of air to produce a mixture
of gaseous and/or liquid fuels and a solid, inert residue (mainly carbon)

28

11. Glossary

Recyclate/Recyclable
Materials

Post-use materials that can be recycled for the original purpose, or for different
purposes.

Recycling

Involves the processing of wastes, into either the same product or a different one.
Many non-hazardous wastes such as paper, glass, cardboard, plastics and scrap
metals can be recycled. Hazardous wastes such as solvents can also be recycled by
specialist companies.

Refuse Derived Fuel (RDF)

A fuel produced from combustible waste that can be stored and transported, or
used directly on site to produce heat and/or power.

Renewables Obligation

Introduced in 2002 by the Department of Trade and Industry, this system creates a
market in tradable certificates (ROCs), within which each electricity supplier must
demonstrate compliance with increasing Government targets for renewable energy
generation.

Solid Recovered Fuel

Refuse Derived Fuel meeting a standard specification, currently under development

by a CEN standards committee.

Source-segregated/
Source-separated

Usually applies to household waste collection systems where recyclable and/or

organic fractions of the waste stream are separated by the householder and are
often collected separately.

Statutory Best Value

Performance Indicators

Local Authorities submit performance data to Government in the form of annual

performance indicators (PIs). The Recycling and Composting PIs have statutory
targets attached to them that Authorities are required to meet.

Syngas

Synthetic gas produced by the thermal decomposition of organic based materials

through pyrolysis and gasification processes. The gas is rich in methane, hydrogen
and carbon monoxide and may be used as a fuel or directly combusted to generate
electricity and/or heat, or for transport applications in fuel cells.

29