Submerged Combustion Melter.
The combustible mixture burns directly into the melt.
Melting bath composed of watercooled metallic panels.
• Submerged combustion produces intense bubbling;
• Intensive mixing of the melt and raw material;
• A large contact area between the bubbles of flame and melt;
• Intensive heat exchange between flame and melt;
• Low emission of NOx (2 times less than in conventional furnaces);
• Improved combustion quality (20% less emissions of unburnt particles);
• Very high furnace output per square meter (20 t/m2/day);
• Very compact size of melting bath (4 m2 for melt output 3t/h);
• Ability to work in "On - Off" mode - need about 2 hours to start or stop;
• 3...5 times cheaper than a standard refractory flame furnace;
• No feeding size material constraint.
Currently there are two abbreviations of this technology: SBM - Submerged Burner Melter and SCM - Submerged Combustion Melter.
Initially technology of melting with submerged burners was developed for hazardous waste treatment (1960): incineration of pesticides, vitrification of radioactive substances.
Then, this technology has been adapted for stone wool and glass wool manufacturing . Two plants were built in Kiev (Ukraine) and Bereza (Belarus). Three production lines in Bereza plant have been operating for more than 10 years.
Currently, submerged combustion technology is used for stone wool and glass wool production by big industrial groups: Saint-Gobain, Knauf, Johns Manville, Owens Corning. Industrial tests of SBM furnace for glass bottles production have been successfully carried out.
Since its creation, an important technological leap has been made in improvement of this melting technology: there are now air-gas and oxygen-gas submerged burners, improved thermal insulation is used in furnaces melting bath and new heat recovery technologies are applied.
Currently there are furnace projects for different melting capacities: 1 t/h, 3t/h, 7t/h
Advantages of submerged melting technology.
- Large contact area between the flame and melting bubbles;
- Intense heat exchange between flame and melt - specific pull rate 20 T/day/m2;
- Intensive mixing inside - rapid transition from one glass composition to another;
- Very uniform chemical composition of melt;
- Low emission of NOx nitrogen oxides (2 times less than in conventional ovens);
- Good melting efficiency - average gas consumption 2 MWh/tone of melt;
- Large granulometry of the batch - pieces of 50-70 mm up to the very fine fraction;
- Can melt very wet waste and intermixed small pieces of metal;
- Compact size (5 times smaller than a conventional oven of the same capacity) - only oven area for 60t /d is 4 m2;
- Ability to work in "On - Off" mode - need about 2-3 hours to start or stop this furnace;
- 3 times cheaper than standard flame furnace - SBM smelter with full equipment for 60 t/d costs around 2,2 M €;
- Long service life - Expensive Ceramic Refractories are not used in this furnace;
- If necessary, SBM smelter can be completely dismantled and assembled elsewhere.
Disadvantages.
- This technology is adapted only for vitrified materials melting - all metal can not be melted in this furnace;
- The melt at the outlet contains many air bubbles - to remove them, need additional equipment;
- Furnace vibrations during operation - need a reinforced supporting structure;
- Very complex visual control of the melting process inside the furnace;
- With air-gas burners, the melt temperature can be reached at 1350 ° C, and with oxygen-gas it can reach 1550 ° C.
- The higher the temperature of the melt, the greater the losses in the cooling water jacket.
Advantages of SBM technology for rock wool production.
- Reduced operating costs by eliminating coke and replacing it with natural gas as fuel for melting;
- Furnace that can work with 100% of waste;
- No need of briquette making workshop - savings around 1 M €;
- Possibility of complete recycling of production waste and and waste from external customers;
- 10 times less dust emissions than in cupola or flame furnace;
- No need of CO treatment system (type Enetex) - savings around € 2m;
- Low investment costs - the melting bath is composed by replaceable metalic panels cooled by water,
- Small footprint - about 4 m2;
SBM furnace application for soluble silicates glass production.
- Standard furnaces for sodium silicate soluble glass production cost 3 ... 5 M€. SBM furnace for 60 T/day costs about 2 M €;
- Small furnace area - instead of one standard furnace, 4 furnaces can be installed and tolal factory capacity can be increased 4 times;
- Ability to work in the "On - Off" mode - if necessary, the melt from furnace can be quickly drained and production will be stopeed for example for weekends;
- Porous melt at the exit of furnace - best dissolution of silicate glass in autoclave;
- SBM furnace consumes 2 times less gas than standard furnace same capacity;
- Very homogeneous melt at the exit of furnace;
- Batch large granulometry - from pieces of 50-70 mm to the dust fraction.
Our solutions.
Turnkey furnace project for waste remelting : broken glass, wet waste of glasswool and rockwool, glass reinforced with steel wires, cathode ray tubes, etc.
Productivity: 4 - 6 tonnes of waste per hour;
Turnkey SBM furnace project for existing production line (rock wool or glass wool).
Productivity - 3 tons of fusion per hour.
Turnkey project of stone wool production line. Capacity - 60 t/day.
This project will be carried out in collaboration with a large manufacturer of stone wool production lines.
Furnace design with a capacity of 10 t / h.
