alternative fuels and refractories
DESCRIPTION
Alternative Fuels and refractoriesTRANSCRIPT
Dipl. Ing. Stefan Thomas
Use of alternative fuels in the cement industry
How can you make Profit?
Total Profit = Tons x sales prices –
(Cost/t production + costs for distribution and sales) x Tons
The Elements of Profit
Total Profit = Tons x sales prices
–
(Cost/t production + costs for distribution and sales) x Tons
Cost/t production
Fix costs independent from plant output
Variable costs depending on plant output
What to do to increase the profit
Total Profit = Tons x sales prices
–
(Cost/t production + costs for distribution and sales) x Tons
What to do to increase the profit
Total Profit = Tons x sales prices
–
(Cost/t production + costs for distribution and sales) x Tons
Variable costs
Fuel Coal, Lignite, Petcoke, heavy oil, gas
Electric Power
Raw Materials Limestone, SiO2, Clay, iron ore, gypsum
Materials consumed explosives, Diesel oil, bags, additives,…
How can you reduce the costs ?
Fuel
Reduce fuel consumption by
Optimized kiln output
Increased cooler efficiency
Controled kiln feed chemistry
Increased heat exchange efficiency
Reduced of kiln stops
How can you reduce the costs ?
Fuel
Reduce fuel costs
Reduce number of kiln stops
Minimize the use of noble fuels
Increase the use of alternative fuels
The use of alternative fuels (and raw materials) is mainly driven by
• Economical aspects
Return on invest
Influence on system
Influence on clinker quality
• Environmental aspects
Permission
Public acceptance
Customer acceptance
Why is it possible to burn alternative fuels in Cement Kilns
• Extreme high process/flame temperatures ~ 2000°C
Waste Combustion: min 850°C
• λ > 1, air excess
• Long retention time in Kiln and Calciner > 6 sec
Waste Combustion min. 2 sec
• Free lime as a good absorbance for hazardous Elements
• No solid waste, all ash is product
Tires; 265
waste oil; 69
SRF commercial waste; 1361
meat & bone meal; 317
SRF from MSW; 212
solvents; 93
sewage sludge; 238others ; 45
Tireswaste oilSRF commercial wastemeat & bone mealSRF from MSWsolventssewage sludgeothers
Usage of SRF in German cement kilns in 2006 Sum: 2.6 Mill tons/a
SRF solid recovered fuel
Substitution Rate in German Cement Kilns 2006 >50%
0,0%
10,0%
20,0%
30,0%
40,0%
50,0%
60,0%
70,0%
2001 2002 2003 2004 2005 2006
Fossil SRF
What are Alternative Fuels
Alternative Fuels
Liquid
• Waste oil
• Solvents
• Animal fat
• Sewage sludge
• Etc.
Solid
• Petcoke
• Tyres chipped or complete
• Animal meal + Bone meal
• Dried Sewage sludge
• RDF – refuse derived fuel from:
Pulp, paper and cardboard; plastics; Packaging;
Textile industry; others
• Scrap wood
• Etc…
Liquid Alternative Fuel
Solvents
Availability is depending on the local market
Calorific value changes from 15 -28 MJ/kg, may content water
Used for main burner
Composition:
• Alcohol (Methanol, Ethanol, Isopropanol)
• Ketone (Aceton)
• Ester (Xylol, Benzol, Toluol)
Liquid Alternative Fuel, Equipment
Solvents
Collecting tray
Unloading device
Health and safety Info
Control equipmentLevel, Temperature, Pressure, gas detector
Stainless Steal Tanks2x100m³
Liquid Alternative Fuel, Equipment
Solvents
Fuel pipes to main burner
Leakproof ConcreteSurface with collectingsump
Pump Station with filters
Mixing equipment out ofquality reasons
Solid Alternative Fuel : some examples
Tires
Availability is depending on the local market
Calorific value 27 MJ/kg,
Chipped 250mm or complete depending on kiln size or dosing system
Used in Preheater, also without calciner
May content water, depending on the environmental conditions
Composition:
• Carbon
• steel
Solid Alternative Fuel
Tires storage
Plant A, all types of tyres
Solid Alternative Fuel
Tires storage
Plant B
Solid Alternative Fuel
Tires storage
Plant C, all types of tires
Storage area
Walking floor bunker for daily/shift consumption
singularize deviceWheel rim detection
Weighing station
Tire transport to kiln
Necessary Equipment for tire use in Cement Kilns
Storage area
Walking floor bunker for daily/shift consumption
singularize deviceWheel rim detection
Weighing station
Tire transport to kiln
Necessary Equipment for tire use in Cement Kilns
Solid Alternative Fuel
TiresAir lock beforepreheater
Solid alternative fuel, Equipment
Precombustion Chamber, up to 7000 kg/h tires ~ 1000 pcs/h
Solid alternative fuel
RDF - refuse derived fuel
Availability is depending on the local market
Calorific value depends on contractingHigh calorific value up to 23 MJ/kgMid calorific value approx. 16 MJ/kgLow calorific value approx. 8 MJ/kg
Water Content up to 15%
Chlorine content depends on contracting 0,3% up to 2%
Size:two dimensional 25 – 35 mm for optimized combustion for main burnerup to 150mm for use in calciner
Used in main burner or calciner
RDF before Preparation
RDF final Product
RDF Preparation
Primary Shredder Secondary ShredderFE Separation Heavy Fractionseparation
RDF final Product
RDF Homogenisation
RDF, constant Quality?
RDF, constant Quality?
RDF Storing and dosing
RDF Input area in a German cement plant
RDF Input area in a German cement plant
RDF Input area in a German cement plant
RDF automatic sampling
You still have Fuel Control?
Primary Air
Coal
RDF
Oil, Waist Oil & Solvents
Alternative Fuels, how main burner looks like
Alternative Fuels, how main burner looks like
Alternative Fuels, how main burner looks like
Axial air channel
Radial air channel
Petcoke channel: 14.000 kg / h
Solid waste: 9.000 kg / h
Natural gas: 6.240 Nm³/ h
Heavy fuel oil: 11.300 kg / h
Waste oil: 9.170 kg / h
The benefit of Alternative Fuels AF
One easy calculation under the following assumptionVARIABLE COSTS
Kiln capacity 3.000 t/dProduction days 330 d/aspecific heat consumption 3.300 kJ/kgHu (coal) noble fuel 27.000 kJ/kgNoble fuel cost at Burner tip 100 EUR/t
Fuel cost 12.100.000 EUR/a
The benefit of Alternative Fuels AF
Fuel Cost with noble fuel 12.100.000 EUR/a
Hu AF 20.000 kJ/kgFuel Costs - 10 EUR/tAF rate 50 %Yearly amount of AF 81.675 t/aAF costs -816.750 EUR/aTotal yearly fuel costs 5.233.250 EUR/a
Your save in variable costs 6.866.750 EUR/a
The benefit of Alternative Fuels AF
Total yearly fuel costs 5.233.250 EUR/a
Emission TradingCO2 from AF does not count!
Price for CO2 at the European Stock Exchange (EEX)http://www.eex.com04.09.2008 24,49 EUR/t CO2
CO2 Emissions from Noble Fuels (100%) 443.666 t CO2/aYou could save CO2 costs 5.432.690 EUR/aOr increase Production by approx. (0,8tCO2/tklinker) 277.291 t/a