Research
Nuclear waste research needs more funding - transmutation
still experimental
The EU is adopting two proposals on legislation to manage
radioactive waste and the safe running and decommissioning of nuclear plants.
But while European countries prepare to bury their high-level waste, EU
commissioners argue that more investment and research is needed to develop more
"radical solutions", including the use of a neutron-bombardment process to 'neutralise'
highly radioactive waste.
Scientists at the Belgian Nuclear Research Centre (SCK/CEN) have
been focusing their efforts on improving the chemical separation and
transmutation of nuclear waste - a process in which high-activity waste is
partially 'neutralised' in an accelerator that reduces the proportion of
long-lived radioactive isotopes in the waste by bombarding it with neutrons.
Transmutation can be used to convert waste containing technetium-99
and iodine-129, very long-lived isotopes that have to be isolated for long
periods because they are prone to dissolving in groundwater and moving through
the environment. Technetium-99 is converted to technetium-100, which decays in
minutes rather than decades. Iodine-129 is similarly converted to a less harmful
isotope.
Transmutation is also effective on long-lived actinides such as
plutonium and americium that decay over thousands of years, but actinides are
difficult to separate from non-radioactive lanthanides also present in waste
that tend to interfere with the transmutation process. Transmutation is at
present economically unfeasible for large-scale commercialisation and is not a
substitute for deep burial, according to the Nuclear Energy Agency.
Meanwhile, the European Commission has adopted two proposals for
directives on nuclear energy management (see related story). The first covers
the safety of nuclear plants from design through to decommissioning, with member
states required to set up independent nuclear safety authorities, and the EU to
ensure that adequate funds are available to cover the costs of safe
decommissioning.
The second directive on radioactive waste management recommends the
geological disposal of high-activity waste i.e. encasing it in glass and burying
it underground in stable locations, at present argued to be the safest method of
containing hazardous radioactive waste. Countries are required to prepare
national disposal programmes and choose disposal sites by 2008, which will have
to be operational by 2018. Low-level waste has to be disposed of by 2013.
The Commission is also working to increase funding for research into
nuclear waste management, which it says is currently inadequately financed. In a
recent visit to a nuclear plant, Loyola de Palacio, Vice-President of the
Commission, said that for nuclear energy to remain an option, the EU must
continue to invest in research and monitor nuclear waste storage, where the safe
disposal of high-level radioactive waste required "radical solutions". Research
programmes would be likely to cost 30 times more than the EU currently spends on
research.
Nuclear power currently meets 35% of the EU's energy needs. To date,
the EU has processed two million cubic metres of low-level waste, while
high-level waste has being held in intermediate storage facilities for the last
50 years. Although the volumes are low - comprising only 5% of total nuclear
waste generated - high-level waste contains 95% of all radioactivity. This type
of waste continues to grow, and needs to be transferred to permanent storage
sites, said de Palacio.
European Research Commissioner Philippe Busquin said that the
selection of sites for the deep burial of nuclear waste had already been made in
Finland and Sweden, who were now preparing to authorise the construction of
underground storage facilities. Countries like France and Belgium were
continuing to investigate the best methods of geological disposal, while Germany
and the UK were taking a different approach by entering into a public dialogue
first, he said.
A high temperature dust filtration system”
Abstract: SWIRLER is an innovative system useful for specific application in the
reduction of dusts present in the hot gases produced in municipal incinerators
for urban solid waste or for gasifying processes. The particle abatement method
is based on the principle of centrifugation of the flow through an axial
centrifuge. This system differs from already existing ones in that it operates
on fumes still at high temperatures. The advantage is that the most polluting
substances are still in a gaseous state and thus, they can be easily separated
by means of dynamic effect from other lighter substances present in the fumes.
Gas enters the single separator, goes through one of its components called
SWIRLER that transforms the flow of gas from axial to helicoidal, thus creating
a swirling action which forces the particles which must be retained against the
walls of the tubular duct and concentrating the dust in an external crown. The
principle flow of the purified gas is aspired into a central duct, while the
secondary flow is conveyed to an external ring which carries it towards the
traditional dust demolition device and is finally sent again to the combustion
chamber. The purified central flow is then sent again to be converted into an
axial flow.
Contact Details
Contact Name: RACAH, Jenny
Organisation: Camera di Commercio Industria Artigianato ed Agricoltura di
Torino
Address: Via San Francesco da Paola 24
City: Torino
Region: NORD OVEST PIEMONTE Torino
Postcode: 10123
Country: ITALY
Telephone Number: +39-10-2423001
Fax Number: +39-10-6456802
E-mail:
alps_ge@tn.village.it
URL:
www.to.camcom.it./irc