ENVIRONMENTAL PROTECTION AND REMEDIATION USING SHS Black sea Energy Policy Conference Athens, 8-9 October, 2008 National Centre for Scientific Research “Demokritos”, 15310, Greece G. Xanthopoulou and G. Vekinis

SHS SELF-PROPAGATING HIGH-TEMPERATURE SYNTHESIS  Highly exothermic reaction of a mixture of powders  Low pre-heating temperature (furnace) but very high reaction (combustion) temperatures up to 4000 o C.  Very high heating and cooling rates: o C/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 Final SHS reaction product COMBUSTION WAVE Pre-heating zone Initial compact of raw material powders Direction of propagation of combustion wave Initiator (optional)

Comparison between SHS and traditional methods for the synthesis and processing of materials

SELF-PROPAGATING HIGH- TEMPERATURE SYNTHESIS (SHS) (SHS) CATALYSTS REFRACTORIES: POROUS OR DENSE INORGANIC PIGMENTS ADVANCED STRUCTURAL CERAMICS - ABRASIVES CERAMIC OR METALLIC MATRIX COMPOSITES ADVANCED INTER- METALLICS Synthesis gas, oxidation, dehydrogenation, hydrogenation, dehydrodimerisat ion, pyrolysis... MgO/Al 2 O 3, pure spinels, kiln walls, furnace insulation etc For ceramics, paper, glazes, plastics, paints, cosmetics, etc VC, B 4 C, TiC, TiN, TiB 2, SiC, CrB, LaB 6, WC, BN, MoSi 2, etc NiAl, FeAl, AlCr, TiNi, CoTi, CuAl, etc WC-Co, TiC-TiB 2, TiB 2 -Al 2 O 3, B 4 C- Al 2 O 3, TiN-Al 2 O 3, etc

The most important pollutants of industrial processes and the main methods of controlling them

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.

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 o C), 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.

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 hydrogenation CATALYSTS Oxidation, pyrolysis, dehydrodimerisation, dehydrogenation hydrogenation CERAMIC ARTICLES Thermal and structural tiles, bricks, refractories CERAMIC ARTICLES Thermal and structural tiles, bricks, refractories INORGANIC PIGMENTS for ceramics, paper, plastics, paints, porcelain, glass INORGANIC PIGMENTS for ceramics, paper, plastics, paints, porcelain, glass PROTECTIVE LAYERS Covering and encapsulation of hazardous wastes PROTECTIVE LAYERS Covering and encapsulation of hazardous wastes

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

Catalytic deep oxidation of methane on SHS catalysts G. Xanthopoulou and G Vekinis, “Deep methane oxidation using catalysts made by SHS”, Applied Catalysis A: General, 199:2 (2000) Inexpensive SHS catalysts offer up to 100% conversion of methane.

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

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