Development, implementation and practical use of process integration for the Iron and steel industry

Transcription

1 Development, implementation and practical use of process integration for the Iron and steel industry Carl-Erik Grip, Luleå University of Technology, dept Energy science 1 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

2 Development, implementation and practical use of process integration for the Iron and steel industry Background Development and implementation of methods Spreadsheet modeling Mathemathical programming Exergy analysis Pinch analysis Getting acceptance Long term organisation of process integration for steelmaking and mining : PRISMA 2 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

3 Development, implementation and practical use of process integration for the Iron and steel industry Background Development and implementation of methods Spreadsheet modeling Mathemathical programming Exergy analysis Pinch analysis Getting acceptance Long term organisation of process integration for steelmaking and mining : PRISMA 3 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

4 Coke plant By-product fuel gas ladle metallurgy Proces Luleå s flow continuous casting blast furnace BOFconverter 800 km hot rolling mill pickling cold rolling mill manufacturing slab furnace coiler Borlänge annealing 4 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

5 Luleå Energy System: Flow sheet and reality Coke making 18 MJ/Nm 3 Power Steam Drying of biomass Mixed gas BOF gas Ore harbour (LKAB) Coke oven plant Iron making Steelmaking 2,7-3 MJ/Nm MJ/Nm 3 CHP Waste gas Bioenergy Steel plant 3km Other users Lime furnace District heating Lulekraft (CHP) Blast furnace Photo: METRIA 5 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

6 Development, implementation and practical use of process integration for the Iron and steel industry Background Development and implementation of methods Spreadsheet modeling Mathemathical programming Exergy analysis Pinch analysis Getting acceptance Long term organisation of process integration for steelmaking and mining : PRISMA 6 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

7 Start of system integration integration in Luleå: System simulations using Spreadsheet models BF plant Coke plant BF Plant BOF plant Rolling Mill Interface CHP plant Other users BOF plant Interface Coke Oven Gas Desulphurisation Variations Flows Prices Economical model Net flow to CHP plant a) Original model (1987) b) Simplified model (1995) 7 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

8 Spreadsheet simulation: Maintaining the energy balance during coke plant revamping 10 Oil in rolling mill, ton/h Coke oven gas to blast furnaces, knm3/h Net cost saving, Index Production in oxygen plant 2, knm3/h 8 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

9 Effect on further development Successful implementation of system models resulted in strong management support for further studies, e.g. alternative iron making, oxygen blast furnace, CO2- lean metallurgy, decision on a new blast furnace. The Swedish Energy agency together with SSAB and other energy intense industries started and financed a Swedish national program for process integration during SSAB chaired it The remind tool for mathematical programming was developed in a series of cooperative projects with LTU, LiU, MEFOS, SSAB and LKAB. 9 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

10 Development, implementation and practical use of process integration for the Iron and steel industry Background Development and implementation of methods Spreadsheet modeling Mathemathical programming Exergy analysis Pinch analysis Getting acceptance Long term organisation of process integration for steelmaking and mining : PRISMA 10 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

11 Mathemathical Programming Procedure (remind) Optimisation Evaluation of result Xxxxxxxxxxxxxxxxxxx Xxxxxxxxxxxxxxxxxxx Xxxxxxxxxxxxxxxx xxxxxxxxxxxxx Data Collection Equation matrix Reality Java-based interface (remind) CPLEX EXCEL 11 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

12 Car fuel from process gas: optimization of gas balance Coke plant Blast Furnace Mix gas CHP Plant Steel plant To Fuel Plant 12 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

13 Refined SSAB model OOOO 500 nnnnn AAAAAA 40 nnnnn 13 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

14 Pareto analysis CO2 emission (t/t) % 98% 96% 94% 92% 90% Material efficiency 14 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

15 Development, implementation and practical use of process integration for the Iron and steel industry Background Development and implementation of methods Spreadsheet modeling Mathemathical programming Exergy analysis Pinch analysis Getting acceptance Long term organisation of process integration for steelmaking and mining : PRISMA 15 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

16 Energy-exergy Balance for the Luleå system Energy balance Oil Gases CHP Electricity District Heating Energy in Steel plant Steel Byproducts Losses Losses Exergy balance Oil Electricity Gas CHP Destroyed District Heating Losses Exergy in Steel plant Steel Byproducts Losses Destroyed 16 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

17 Practical Use of Exergy studies in Luleå Exergy and energy can be calculated from the same data. Approach: Combined energy and exergy balances presented Exergy used only as pedagogic tool show Energy quality Good acceptance on that level Example: Mapping of rest energies Interesting sources both in coke and steel plant. ORC for Electricity: Technically OK. Economically impossible (Legal system treats electricity as fossile) 17 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

18 Development, implementation and practical use of process integration for the Iron and steel industry Background Development and implementation of methods Spreadsheet modeling Mathemathical programming Exergy analysis Pinch analysis Getting acceptance Long term organisation of process integration for steelmaking and mining : PRISMA 18 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

19 Pinch analysis Main objective: Pinch analysis of coke plant Gas Cleaning Additional studies: Coke plant total, Ironmaking and steelmaking plant, Total SSAB Site Q H minimum Part of hot stream in heat exchanger EB 2261 LP steam for the benzene stripper Q C minimum Grand composite curve. Coke plant gas cleaning. Reference case. 19 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

20 Coke oven plant. Calculated effect (kw) of three step improvement 20 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

21 Pinch analysis, some results A potential was shown for steam saving in Coke plant, e.g. by optimal use of medium pressure steam and further potential with improved recovery methods. Pinch analysis is well fitted for that part A study including Steel making and Ironmaking and merging to whole system showed potential savings with common steam system was shown. Pinch analysis more problematic for that part. 21 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

22 Development, implementation and practical use of process integration for the Iron and steel industry Background Development and implementation of methods Spreadsheet modeling Mathemathical programming Exergy analysis Pinch analysis Getting acceptance Long term organisation of process integration for steelmaking and mining : PRISMA 22 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

23 Acceptance: important factors Management support from the start. Plan the work to create practically useful results at an early stage. Include plant people in the development and validation throughout the process. Intuitive knowledge can give validation information! Sophistication is necessary. Over-sophistication is dangerous! Networks with enough critical mass are necessary for long term continuity. 23 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

24 Development, implementation and practical use of process integration for the Iron and steel industry Background Development and implementation of methods Spreadsheet modeling Mathemathical programming Exergy analysis Pinch analysis Getting acceptance Long term organisation of process integration for steelmaking and mining : PRISMA 24 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

25 PRISMA, an Institute Excellence Centre for Process Integration in Steelmaking PRISMA was established in 2006, and has been supported for two three year periods a by number of process industries and two government organizations It is located at Swerea MEFOS in Luleå. Presently about nine full time researchers are involved in research on Process Integration applications in the metallurgical industry. SSAB EMEA, SSAB Merox, Ruukki Metals, LKAB,Höganäs AB, AGA Linde and Lulekraft have contracted on joint economical support for a new three year period 25 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

26 Process integration models at PRISMA Scrap based Steel produktion Heat and Power Integrated Steel produktion Mining with ore treatment and pelletizing 26 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

27 Practical PI applications in steel & mining Integrated steel production Optimized use of energy gas (SSAB, Ruukki) Optimal content of coal volatiles for energy efficient steel production (Ruukki) Applications and possibilities of Oxygen and Oxyfuel technology (AGA Linde) Scrap-based steel production Optimal scrap mix, Optimized use of energy Others Optimized industrial heating systems(lkab) Heat collaboration with society (Lulekraft, Luleåenergi) Moving a city with energy network (LTU, TVAB, LKAB) 27 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

28 Conclusions The energy system of an integrated steel plant is complex. Work with system integration started 1987 A method for mathematical programming (remind ) was developed in cooperative projects with SSAB,LTU, LiU, MEFOS and LKAB. It is now a standard tool for PI in steel industry Other methods have been used for specific purposes Industrial acceptance is crucial. Important parameters were discussed An institute excellence center (PRISMA) was established as a network with sufficient critical mass for long term continuity 28 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013

29 Development, implementation and practical use of process integration for the Iron and steel industry Carl-Erik Grip, Luleå University of Technology, dept Energy science The end 29 C E Grip, International Process Integration Jubilee Conference, Gothenburg, 2013