ghghghghghg

1
ENVIRONMENTAL PROTECTION AND REMEDIATION USING
SHS
G. Xanthopoulou and G. Vekinis
National Centre for Scientific Research
Demokritos, 15310, Greece gxantho_at_ims.demokrito
s.gr
Black sea Energy Policy Conference Athens, 8-9
October, 2008
2
SHS SELF-PROPAGATING HIGH-TEMPERATURE SYNTHESIS
Final SHS reaction product
Initiator (optional)
COMBUSTION WAVE
Direction of propagation of combustion wave
Pre-heating zone
Initial compact of raw material powders

• Highly exothermic reaction of a mixture of
  powders
• Low pre-heating temperature (furnace) but very
  high reaction (combustion) temperatures up to
  4000 oC.
• Very high heating and cooling rates 103 - 106
  oC/sec.
• Very short completion times, of the order of
  minutes - possibility for just-in-time
  manufacturing
• Much lower energy consumption than traditional
  production methods much lower energy costs
• Relatively simple process - easily adaptable to
  industrial scale
• Easily controlled physico-chemical properties of
  the products
• Much lower environmental impact in comparison
  with traditional production methods.
• Large range of industrial materials and products
  produced

3
Comparison between SHS and traditional methods
for the synthesis and processing of materials
4
SELF-PROPAGATING HIGH-TEMPERATURE SYNTHESIS (SHS)
CATALYSTS
REFRACTORIES POROUS OR DENSE
INORGANIC PIGMENTS
ADVANCED STRUCTURAL CERAMICS - ABRASIVES
CERAMIC OR METALLIC MATRIX COMPOSITES
ADVANCED INTER-METALLICS
Synthesis gas, oxidation, dehydrogenation,hydrogen
ation, dehydrodimerisation, pyrolysis...
MgO/Al2O3, pure spinels, kiln walls, furnace
insulation etc
For ceramics, paper, glazes, plastics, paints,
cosmetics, etc
VC, B4C, TiC, TiN, TiB2, SiC, CrB, LaB6, WC, BN,
MoSi2, etc
WC-Co, TiC-TiB2, TiB2-Al2O3, B4C-Al2O3,
TiN-Al2O3, etc
NiAl, FeAl, AlCr, TiNi, CoTi, CuAl, etc
5
The most important pollutants of industrial
processes and the main methods of controlling them
6
SHS as a reliable and effective method for
forming protective coatings of dangerous solid
wastes

• SHS can be carried out at room temperature - it
  does not need a furnace. As a result.
• SHS may be utilised for the creation, in-situ,
  of hard, protective coatings of dangerous, large
  volume, solid wastes, such as mining dumps.
• The waste materials can be covered with a thin
  layer of an SHS mixture, which partially melts
  and solidifies following SHS initiation. The
  hard, protective coating safely restricts
  air-born or water-born pollution.
• Especially dangerous and toxic (e.g. radioactive)
  solid wastes may also be consolidated and
  neutralised by SHS, prior to burial or
  encapsulation.
• SHS is cheap, easily adaptable and can be used in
  the field without special equipment or
  specialised training. Ideal for isolated or
  difficult to reach areas.

7
Quick and inexpensive cutting of large scale
metallic structures using SHS.

• The SHS combustion wave can be controlled so that
  it propagates both transversely and
  longitudinally, at room-temperature. As a
  result.
• SHS may be utilised for cutting large-scale
  metallic structures, such as boats, buildings
  etc.
• A narrow layer of SHS combustion mixture is
  placed on the cut-line and the SHS reaction is
  initiated from one end. The combustion
  temperature is very high (more than 2500 oC),
  locally melting and cutting the metal.
  Simultaneously, it preheats and initiates the
  neighbouring SHS mixture enabling the propagation
  of SHS across the thickness of the metal plate
  and along the cut-line.
• SHS is quick, inexpensive and easy to apply and
  does not need specialised equipment or special
  training.

8
VARIOUS PRODUCTS OF UTILISATION OF SOLID
INDUSTRIAL WASTES BY SHS.
MARBLE WASTES
LEAD PRODUCTION WASTES
BAUXITE PRODUCTION WASTES
CHROMITE WASTES
PYRITE WASTES
FERROUS ALLOYS WASTES
SELF-PROPAGATING HIGH-TEMPERATURE SYNTHESIS
CATALYSTS Oxidation, pyrolysis,
dehydrodimerisation, dehydrogenation hydrogenatio
n
CERAMIC ARTICLES Thermal and structural tiles,
bricks, refractories
INORGANIC PIGMENTS for ceramics, paper, plastics,
paints, porcelain, glass
PROTECTIVE LAYERS Covering and encapsulation of
hazardous wastes
9
Catalytic oxidation of carbon monoxide on SHS
catalysts
Comparison between SHS catalysts of the system
Cu-Cr-O and commercial catalyst systems for
carbon monoxide oxidation in exhaust gases of
internal combustion engines.
G. Xanthopoulou and G.Vekinis, Catalytic
oxidation of CO by a Cu-Cr-O catalyst made by
SHS, Applied Catalysis B Environmental,
19(1998), p.37-44.
10
Catalytic deep oxidation of methane on SHS
catalysts
Inexpensive SHS catalysts offer up to 100
conversion of methane .
G. Xanthopoulou and G Vekinis, Deep methane
oxidation using catalysts made by SHS, Applied
Catalysis A General, 1992 (2000)227-238
11
SHS catalysts for combustion of soot
Burn-out temperature of various types of soot in
the presence of various materials
Burn-out temperature of diesel soot in the
presence of various SHS catalyst materials
12
Conclusion

• SHS may be utilised for the creation, in-situ, of
  hard, protective coatings of dangerous, large
  volume, solid wastes
• SHS may be utilised for cutting large-scale
  metallic structures, such as boats, buildings
  etc.
• Especially dangerous and toxic (e.g. radioactive)
  solid wastes may be consolidated and neutralised
  by SHS, prior to burial or encapsulation
• SHS catalysts are very active and cheap for
  environmental uses
• Easy recycling of many solid wastes to product
• SHS-is low energy consumption technology of
  ceramic materials production