IWWG Task Group on

THERMAL TREATMENTS

Chair: Prof. Umberto Arena

Aim of the TGTT

• Communicating properly and to a large part of the population about process, technological and environmental aspects of the main thermal treatments able to produce energy from wastes efficiently;
• Comparing the different processes (combustion, gasification, pyrolysis) and technologies of these treatments, for different plant sizes and for different waste types.

Structure of the TGTT

• Only researchers and scientists from the Academia or independent Research Centres, that remain open to any external contribution from industrial and service companies and from NGOs, environmental associations and civic committees.

Possible main products of the TGTT activity

•    An extensive and agreed review about those processes and technologies that can be consider reliable for different waste types and various plant sizes.
•    An easy-to-read summary addressed to a large part of the population, which refers to the extensive review for deepening and further reading.
•    Different lengths extracts from the summary to be published in newspapers or presented at talks in divulgative conferences.
•    A TGTT website (hosted by IWWG) which could also accommodate requests and concerns from ordinary citizens (and therefore be multilingual) and could have links to/from websites of independent institutions interested to the field.

Proposal of the first stages work of the TGTT

It is likely that TGTT’s activity could be easier and better organized if we share it in two parts: the first specifically dedicated to municipal solid wastes and the second focused on industrial wastes.
Moreover, it's proposed to focus just on the direct combustion process of incineration and to the indirect combustion process of gasification. Pyrolysis processes and the other types of combined thermal processing systems (pyrolysis + gasification; pyrolysis + combustion; gasification + pyrolysis + combustion; pyrolysis + melting; etc.) could be considered not immediately commercial available. This should make easier and simpler the review process, at this first stage.
In the following, there are some proposals for the organization of the work related to MSW.

1st Stage. Definitions and Taxonomy

It is useful to prepare precise but simple (i.e. able to be easy communicate “to a large part of the population”) definitions of the main terms that will be used in the long or short reports, such as:
   Municipal solid waste
   Industrial waste
   Residual waste (restwaste)
   RDF
   SRF
   Energy-from-waste (Waste-to-energy) process
   Direct combustion
   Indirect combustion
   Thermal Treatments
   Advanced thermal treatments
   Furnace
   Heat recovery
   Gross and net energy production
   Flue gas
   Fuel gas
   Bottom ash
   Fly ash
   APC residue
   Dust or particulate matter
   Heavy metals
   Acid and corrosive gases
   Products of incomplete combustion
   Waste water
   …

It should be not “an infinite list” but an useful glossary that could be easy consulted.
We could complete this glossary with some simple graph with a taxonomy of the thermal treatments in the framework of an integrated waste management system.

2nd Stage. Data Acquisition

It would be useful to select a restrict number of scientific/technological reviews, which can be considered as common and reliable references for our work, i.e. a sort of databank of the TGTT. There are some important official documents (such as the Best Reference Document on Waste Incineration prepared by the European Commission, and others, by US-EPA or DEFRA_UK, etc.) but also to some important reviews on specific aspects of thermal treatments (process, emission control, life-cycle or substance flow analyses; epidemiology studies).
It is important at this stage the co-operation of industrial partners, i.e. plant manufacturers and managers of thermal treatment plants. Their contribution is crucial. We have to contact a certain number of them (Preliminary contacts have taken place with Foster Wheeler, CNIM, Martin Gmbh and A2A for incineration processes and with 7-hills and Ebara for gasification processes, but it is obviously a partial list).

In the following, a list of the main aspects about which it is necessary to collect specific, reliable and up-to-date information is proposed.

➢    Composition (i.e. elemental or ultimate analysis, extended to the main elements of ash) of waste streams in input to different thermal treatment plants, i.e.
   o    MSW
   o    Restwaste (residual waste)
   o    RDF.

➢    Composition of (gas/liquid/solid) streams in output from direct combustion and indirect combustion processes.
➢    Data directly collected “from the field”, and related to:
   o    Emissions (in term of flow rate and composition) to air, wastewater and solid residue from the thermal treatment of one ton of municipal solid waste
   o    Plant availability
   o    Gross and net production of electric and thermal energy
   o    Specific (i.e. €/treated ton) investment and operating costs
   o    Air pollution monitoring over areas wit a TT plant in operation
   o    Epidemiology studies over areas wit a TT plant in operation since few years.

3rd Stage. Definition of Working Groups

It could be useful to have a few working groups (i.e. subgroups of our TG), focused on specific aspects. A possible proposal could be:
➢    Thermal treatment processes
➢    Thermal treatment technologies
➢    Air pollution control systems
➢    Environmental and health risk assessment tools for TT plants or processes
➢    Protocols of air pollution monitoring
➢    Protocols of epidemiology studies

I will wait for your wishes and suggestions. You should send to me your preferences about the participation to the activities of a specific working group and/or your proposals for a different organization.

Proposal of an Agenda of TGTT activities

A possible meeting could be organized when some work has been done and, in any case, in conjunction with an important international conference on waste management.
Next steps could be:
1.    Draft of definitions and taxonomy: end of April.
2.    First part of data acquisition: from February to June.
3.    Definition of the WGs: end of March.
4.    Definition of structure of the reports of each WGs: end of May.
5.    Meeting of the TGTT: at the Venice conference in November 8-11, 2010.

Contact person:

Umberto Arena

E-mail: umberto.arena@unina2.it