1. Submerged Combustion Melting The Next Generation Melting System
DOE
David Rue
Gas Technology Institute
66th Glass Problems Conference
U. Of Illinois, Champaign, IL
Oct. 26, 2005

2. Submerged Combustion Melting Principle
Air-fuel or oxygen-fuel mixture is fired directly into a pool of hot melt
intense combustion
direct contact heat transfer - combustion products bubble through the melt
reduced NOx formation
reduced CO and unburned hydrocarbon emissions
High rate of heat transfer and rapid mass transfer
High thermal efficiency
Reduced melter size

3. Submerged Combustion Melting Features
Melting and mixing in a single device
No external device needs to contact the melt
Short residence time from forced convective heating and mixing
Melter is simple, robust, and reliable
Small size – low capital cost
SCM is easily started and stopped in a few hours
No hot repair work required
Compatible with other segmented melting process steps
Charging
Conditioning
heat recovery

4. GTI and GI SCM History
Gas Institute (Ukraine) developed SCM for mixed nuclear waste vitrification and industrial melting – not deployed
Process simplified and commercial, air-fired units operating more than 10 years for other applications
two 3-ton/h rockwool SCM units in Kiev, Ukraine
three 3-ton/h rockwool SCM units in Byarosa, Belarus
One SCM cement aggregate unit in Noril’sk Russia
GTI licensed SCM for applications outside former Soviet Union
GTI has patents and background IP in melting, submerged firing, and heat recovery
500-lb/h SCM unit fabricated and operated at GTI
Multiple melts including basalt and sodium silicate
First use of oxy-gas burners

5. SCM 3 ton/h Mineral Wool SCM in Belarus
SCM Furnace
Loading Feed Hopper
SCM Interior

6. From Melt to Mineral Wool
Molten Slag Channel
Blow Chamber
4 Wheel Fiber Spinner
Product Fiber Mat

7. SCM Advantages Energy savings >20% vs. oxy-gas melters
>55% capital cost reduction
Compact with very little refractory – 80% refractory reduction
Melt area is 15% of tank melter area (0.6 ft2/ton/day)
Reduced emissions
NOx >50% below oxy-gas melters
CO and unburned hydrocarbons reduced >20%
Rapid switching of melt composition
Short residence time - rapid heat transfer
Reliable, proven melting technology
Feed flexibility lowers batch and feeder cost
Mates with conditioning and heat recovery steps
Excellent redox and color control
SCM Advantages

8. Approaches to Glass Melting
Single tank
Compromise simple and reliable, but non-optimized approach
Holding furnaces, fining, and conditioning are needed after the melter for many glass products
Staged or ‘segmented’
Melting, mixing, refining, conditioning, heat recovery, etc. are optimized as needed for the glass product
highly flexible with many potential process advantages
Requires eloquent design for reliability and to avoid over-complexity and high capital cost

9. NGMS Project Underway at GTI
Demonstrate melting and homogenization stage of low capital cost, energy efficient NGMS process for all industrially produced glass
Sponsors
DOE
NYSERDA
Gas industry
Consortium actively supporting development and commercialization of SCM fro NGMS
Corning Incorporated - PPG Industries, Inc.
Johns Manville - Schott North America
Owens Corning

10. Batch-Scale SCM at GTI

11. Lab-Scale SCM Industry batch melted to glass Full glass range melted
Low-temp. soda-lime glass
High-temp ‘hard’ LCD glass
Borosilicate glass
Scrap reinforcing fiberglass
Batch feed
Continuous discharge
Evaluation of glass product before pilot SCM fabrication
Components scaled for ton/h pilot SCM
Product glass is fully melted and homogeneous

12. Special Tap Designed for Glass Melts
Soda-Lime Glass

13. Scrap Fiberglass – Melt Sampling

14. Pilot-Scale SCM Unit
Objective – continuous feed and discharge – made easier with
Larger capacity melter ( ton/h)\
Demonstrated platinum discharge tap
Most components are in place and tested
Melter, burners, cooling water chiller needed
Added instrumentation into data acquisition system
Multiple burners spaced to create
Uniform temperature profile
Desired mixing and residence time distributions
Elimination of poor mixing zones in corners and along walls
Flexibility built into the unit
Changeable burner patterns
Provisions for two or more discharge locations
Provisions for two feed locations

15. Glass Quality Varies Dramatically
Acceptable Bubble Count
Lower-cost glass making must have BOTH
High intensity melting
Rapid refining
Quality varies over 5 orders of magnitude
SCM alone –
Makes fully melted homogeneous glass
Only makes lowest quality glass
SCM works well with all external refining methods
Glass Market
Seeds/Oz
Relative Seed Quality
LCD Display
10x better than TV panel glass
TV Panel
10x better than float glass
Float/Flat
1, ,000x better than container glass
Textile Fiber
100x better than container glass
Tableware
< 2
10x better than container glass
Lighting Glass
~ 25
2x better than container glass
Container
10-20
10x better than funnel glass
TV Funnel
~ 200
2x better than wool insulation fiberglass
Insulation Fiber
~ 400

16. NGMS (SCM AND Rapid Refining)
If refining is slow, the capital cost benefits of low-cost, high-intensity melting are lost
Potential refining approaches include
Sonic
Lab-scale tested
Potentially low cost and very rapid, easily installed
Helium (inert gas)
Entering commercial trials
Helium cost is acceptable, not usable on all glasses
Thin film
Limited commercial use
Particularly good SCM match, bubbles are large and no CO2
Reduced pressure
Requires good control, hardware is expensive
centrifugal
Pilot-scale tested
Complex hardware, potentially very rapid

17. Toward Commercialization
Already completed
SCM concept
Pilot-scale oncept validation, including combustion system
Initial commercial use for low-quality products (mineral wool, aggregate)
Current activities – through 2006
Lab-scale melting of full range of industrial glass and fiberglass scrap
Batch feed and continuous discharge using oxy-gas burners
CFD and physical modeling of SCM
Design, fabrication, and operation of continuous ton/h pilot-scale SCM
Preparations for first industrial demo-scale SCM
Design, construction of first commercial SCM making abrasives from steel industry waste and cullet (northern IN)

18. Next Steps
Plan first glass industry plant demo-scale 1-4 ton/h SCM
Fiberglass or scrap fiberglass
Test unit not replacing existing melter
Rapid conditioning work to develop NGMS for all industrial glass compositions
2009+
Demo-scale SCM and NGMS units in consortium member plants
Initial replacement of current melters with NGMS
2012+
Fully developed and commercially demonstrated NGMS using SCM
Licensing of NGMS to non-consortium member glass companies

19. Commercialization Pathway
Expected order of market entry
Scrap fiberglass
Fiberglass
Specialty glass (pressed and blown)
Specialty glass (optical fiber, LCD, etc.)
Container glass
Flat glass
Consortium agreement lays out company access priority to the NGMS technology
Consortium member companies
GMIC member companies
Non-GMIC glass companies