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uid metal as the product; it did not include the subsequent, product-specific, less energy intensive processes for casting, rolling and finishing, mainly important for their material efficiency. Calculations of emissions and costs of the production routes took place by process analysis and aggregation of the individual processes into production routes. First, individual process data were collected, including consumption and production and data on investment and operation costs [1-9,11,12,14-18,21-23]. Stacking of the processes into production routes allowed calculation of the consumption and production data per unit product. Subsequent combination of these data with prices [9], carbon contents and CO2 emission factors resulted in costs and CO2 emissions for each product. As always in process analysis, system boundaries presented a problem. As all selected production routes use electricity or produce excess energy, the CO2 emissions to be attributed to the production routes depended on the technology applied outside the base metal industry. Therefore, the emissions were calculated for two CO2 emission factors of the electricity production, of 0 and 0.1 tonne CO2 per GJe. Nuclear, solar, wind and water based power plants or fossil power plants with CO2 removal results in a (near) zero emission factor, while 0.1 tonne CO2 per GJe represents the current European average. Conversion of excess energy emerging from a production route to electricity at an efficiency of 40% allowed subtraction of the avoided CO2 emissions in the electricity sector from the emissions by steel production. Steam production may also have varying emissions. There is no separate scenario: 0.06 t CO2 per GJ steam emission factor accompanies the high electricity emissions factor; zero emissions for steam accompany the zero electricity emissions factor. For steel, two additional, partly external parameters were used to define scenarios. For both scrap addition and CO2 removal two additional scenario parameters were defined, resulting in a total of 8 scenarios. The steelmaker decides on scrap addition, but the possibilities for scrap addition strongly depend on external factors. Likewise, CO2 removal is a technique applied by the steel producer, but transport and storage require external infrastructure, involving external decision makers. Steel Production The selection of steel production routes, listed in table 1, represents the four main types of liquid steel production, namely the blast furnace, smelting-reduction, direct reduction and scrap based routes, with two of each. In the EC, 1993, the conventional blast furnace route accounted for about 88 million tonnes crude steel, and scrap based electric steelmaking for about 44 million tonnes [10], with application of best practice techiques resulting in over 150 and 9 Mt CO2 emissions, respectively. Table 1 Important characteristics of the production routes Route Energy input Energy output Number of processes CO2 removal Proces Type GJtot * GJe* Gas* Steam* Total CO2 rate ECU/t removal** % CO2*** BF150 coal 19.6 3.1 5 1 (p) 80 32 BF250 coal 16.7 2.5 5 1 (p) 90 30 COREX coal 28.3 10.8 4 1 (p) 90 30 CCF coal 18.8 3.5 5.5 3 1 (p) 90 30 MIDREX gas, electricity 14.3 1.6 3 1 (s) 90 10 Circofer coal, electricity 16.1 1.6 3 1 (s) 90 10 ACEAF electricity 1.7 1.4 1 DCEAF electricity, coal 1.7 0.9 1 * Values for low scrap addition, GJ per tonne steel. **(p) indicates that removal is possible, (s) that removal is part of tion. *** total of removal, transport and storage. normal process opera- A thorough description of all processes in detail would be too elaborate, but it is essential to provide some background in<strong>format</strong>ion on the analysed production routes. Table 1 lists some characteristics of the the produc-
tion routes that are important for the emissions. Figure 1 gives a schematical representation of each production route. The air blast furnace route represents the current state of the art primary steel production The oxygen blast furnace is in an experimental stage. Currently, several COREX plants are commercially operational; CCF still is in an experimental stage. MIDREX is the largest direct reduction process by production volume, while Circofer is on the edge of commercial introduction. The scrap based production routes use the electric arc furnace to melt and process steel scrap. The AC furnace [9] represents the major part of existing production capacity. The DC furnace and comparable EAFs are commercially operational, but the AC furnace still is by far the most common electric steelmaking process. Due to contaminants in the scrap, scrap based steel seldom is a fully fledged alternative to primary steel. Scenario results Figures 2 and 3 present the costs and emissions for the base case, assuming 0.1 tonne CO2 per tonne of GJe generated, 12% scrap addition in primary oxysteel processes, zero scrap addition in DR routes. and no CO2 removal. Following figures will show the influence of the emission factor of the electricity sector and CO2 removal. Declines in the electricity emissions factor have double effects. The emissions of electric steelmaking decrease, while the net CO2 emissions of the oxygen steelmaking routes increase, as the emissions avoided by converting excess energy to electricity decrease. Especially CCF and, even more so, COREX, with their large excess energy productions are at a disadvantage, while the blast furnace routes are hardly affected. The DRI and scrap based routes profit from the low emission factor of electricity generation; the AC EAF route even has near zero emissions.
Page 1 and 2: Workshop Factor 2/Factor 10 Proceed
Page 3 and 4: The Impact of GHG Emission Reductio
Page 5 and 6: N2O INDUSTRY OTHER GHG CH4 LANDFILL
Page 7 and 8: history of use. The figure indicate
Page 9 and 10: Emission mitigation options The fol
Page 11 and 12: The contribution of the materials s
Page 13 and 14: [MT AL/YEAR] 25 20 15 10 5 0 BC 50
Page 15 and 16: What are the dynamics of the materi
Page 17 and 18: Material efficiency improvement for
Page 19 and 20: Table 1.1 First order estimate of e
Page 21 and 22: PET bottles normally are made out o
Page 23 and 24: To model the category boxes we will
Page 25 and 26: 2.8 Pallets The last packaging cate
Page 27 and 28: they are not a result of the MARKAL
Page 29 and 30: Table 4.1 (continued) The use of pa
Page 31 and 32: or keep it fresh and their second c
Page 33 and 34: [33] Packaging Week 1992-1997, many
Page 35 and 36: GER values Direct energy use (MJ/vk
Page 37 and 38: ogy for igniting the engine, valve
Page 39 and 40: Table 1 gives an overview of improv
Page 41 and 42: Implementing growth of mobility dem
Page 43 and 44: Realising the 80% reduction potenti
Page 45: CO2 Emissions of Metal Production T
Page 49 and 50: From figures 4 and 5, CO2 removal e
Page 51 and 52: Table 3 Emissions per tonne liquid
Page 53 and 54: Table 6 CO2 emissions per tonne liq
Page 55 and 56: DCEAF Direct Current Electric Arc F
Page 57 and 58: Verslag van de workshop commentaren
Page 59 and 60: Transportmiddelen Referent dhr. Smo
Page 61 and 62: Gebouwen en Infrastructuur Referent
Page 63 and 64: Referent dhr. Gouwens, TNO-Bouw 1 R
Page 65 and 66: Metalen Referent dhr.de Jong, Hoogo
Page 67 and 68: Algemene vragen en forumdiscussie D
Page 69 and 70: 3 Wat voor problemen zouden we als
Page 71: ir. R. van Duin (Bureau B&G) drs.ir

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