ENGINEERING Cokeless Cupola Furnaces Economical and environmentally melting plants Development Planning Realization
Cokeless cupola furnaces from Düker over years of experience in iron casting The name Düker has stood for top quality iron casting for more than years. Today we are one of the leading manufacturers of fittings, pressure pipe fittings for drinking water and gas supplies and of pipes and fittings for drainage technology. We also manufacture highly resistant enamelled components and pipes for the chemical and pharmaceutical industries. Another production field of our business is job castings where we act as a contract manufacturer for parts for the printing, automotive and mechanical engineering industries. Our own cokeless cupola at our plant in Karlstadt Düker Engineering worldwide service A comparison of melting furnaces With this background of immense experience, we also plan and build When planning a melting operating, at some stage the question of the type complete centrifugal casting plants, cokeless cupola furnaces and of melting furnace to be installed will be raised. In principle there are two Consultancy control systems for manufacturing business all over the world. different processes to choose from: Cupola furnaces and electric melting furnaces. Each of these systems has its own individual design which depends on Service Cokeless cupolas from Düker Planning the site conditions and the specific requirements of the customer. Since we have also been using our systems for many years for our own production operation, our customers have a unique range of expertise at their disposal, which is constantly being updated and extended. Cupolas melt pig iron, defective castings and steel scrap and use coke, mineral oil or natural gas as fuel. They are the preferred continuous melting units for iron foundries since they can supply high quantities in constant quality. As the name suggests, electric furnaces use electricity to power them and are used for discontinuous applications with frequent analysis changes. Certified quality: We received certification to DIN EN ISO 9001 way back in 1993. Since then our quality man- Training Implementation/ Design We thereby offer our customers worldwide a convenient and customized all-round service which is virtually unique from agement system has been updated and improved on an on-going basis by means of regu- the design, planning and construction to assembly, commissioning lar inspections and also internal and external Installation and training your personnel you receive everything from a single source. audits. 2 3
Cokeless cupolas from Düker economical and environmental Cokeless cupolas ideally use natural gas as fuel. This gives them a better heat balance and con- siderably better emission values. Overall this results in a whole series of major ben- efits compared to alternative furnace systems such as coke-fired cupolas. KW cupola HW-Lz cupola liningless KW cupola, or O 2 HW-Lz cupola with lining HW cupola liningless KW cupola, and O 2 Energy consumption in MJ 1525 C tapping temp./ 1 ton liqud iron GJS KW cupola and O 2 HW cupola, without material cooling, daily alternating operating mode Cokeless cupola, gas-fired with superheater Energy use for melting in cupolas in % 1 C cupola tapping temp. 70 KW = Cold wind HW = Hot wind Hw-Lz = Hot wind for long term campaign O 2 = Oxygen Environmental balance of the cokeless, natural gas-fired cupola Cokeless cupola, KW + O 2, electric superheating 4975 3926 2443 1000 60 50 40 30 20 10 Convincing benefits Charging expensive coke stores not required Melting the melting process is easier to control with natural gas less slag formation cleaner primary energy constant tapping temperature with flexible output the melting process can be interrupted without any problem Superheater low use of additional electrical energy required accurate carburisation base iron does not have to be desulphurised Quality uniform analysis is possible excellent flow properties of the molten metal very low volumes of transition iron ideal melting losses for C, Si and Mn no sulphur pick-up Economy low purchase cost for new systems simple conversion of existing cupolas low costs for dust extraction perfect energy use with duplex system Operating costs for melting GJS base iron in cokeless cupolas Energy Unit Consumption/t GJS 1.1 Natural gas consumption Preheating the furnace m 3 600 Melting m 3 48-52 1.2 Electrical energy consumption a.) Superheater KWh Superheating KWh 64,0 Keeping warm KWh 15,0 b.) Auxiliary mode KWh 25,0 1.3 Refractory consumption Shaft-blast furnace kg 5-8 Siphon kg 0,7 Superheater kg 0,5 1.4 Water consumption m 3 0,4 1.5 Oxygen m 3 19,7 1.6 Metallic charging Steel %/t 25-35 Pig iron %/t 20-30 Returns %/t 35-55 1.7 Alloy-materials/Additives Carburisation %/t 1,1 Si-blanks %/t 0,8 Ceramic spheres %/t 0,95 Slag-forming constituent %/t 0,3 Energy use MJ/ T Fe Carbon dioxide emissions kg/ T Fe Sulphur dioxide emissions kg/ T Fe Environment 4 450 2,5 4000 400 Coke cupola no air pollution with sulphur compounds 3 350 2,0 low level of pollutants in the slag 3000 300 Cokeless cupola 1,5 no CaC 2 slag from GJS production 2 250 2000 200 reduced nuisance emissions 1,0 1 150 low duct content in the flue gas 1000 100 50 0,5 4 5
Cokeless cupolas from Düker added value that pays dividends every day This is how a cokeless cupola works Charging and operating data of the cokeless cupola Control equipment made by Düker First of all the grating in the furnace is covered GJL GJL GJS GJS with ceramic spheres. Then the preheating phase begins which takes around 45 minutes. After this the cokeless cupola is fed with metallic charge materials and slag-forming constituents. Charge material Return (kg) 400 400 Cast iron scrap (kg) 400 Steel scrap (kg) 200 350 Pig iron (kg) 250 The hot combustion gases from the gas burners flow through the ceramic sphere bed and intensively heat the charge material. This melts and flows on to the ceramic spheres. Thereby it is superheated and drips into the bottom of the furnace. Slag and iron are finally separated from each other in the furnace s siphon. Just 15 minutes after the first furnace charge has been inserted, the first iron will flow into the electrically heated superheater where the required temperature and alloy are adjusted. The furnace gas generated by the melting process is continuously exhausted, cooled and purified by dry filters in the top section of the furnace in a gas/air exchanger. Shaft cooling system Blast pipe Ceramic sphere bed Water-cooled grid Gas burner Siphon Superheater Inductor Slag-forming constituents (kg) 35 30 Consumption of natural gas (m 3 ) 50 50 Consumption of ceramic spheres (kg) 9,5 9,5 Consumption of refractory materials (kg) 9 9 Consumption of water (m 3 ) 0,4 0,4 Consumption of electricity (KWh) 3 Combustion air (m ) 80 80 Flue gas (m 3 ) 600 600 All figures are relative to one ton of cast iron Analysis of the production of GJL/GJS C Si Mn P S GJL cupola tapped iron 1400-1420 C 2,8 1,8 0,4 0,06 0,03 GJL liquid iron 1480 C at superheater 3,3 2,3 0,6 0,06 0,03 GJS cupola tapped iron 1400-1410 C 2,6 1,6 0,2 0,04 0,09 GJS liquid iron 1520 C at superheater 3,7 1,6 0,2 0,04 0,09 With our process control systems you can control all the parameters for your cupola and the periphery conveniently from your PC. A clear visualisation system shows you all the characteristic data permanently and you can then adjust them and save them if necessary. This ensures the uniform high quality of the melting process. We actually make our control systems at our plant in Karlstadt, Germany. They undergo ongoing development and improvements. This means that our customers can rely on the fact that they will always have the very latest technology for years to come. Figures in % Modernisation of existing cupolas Training and maintenance We can convert existing cupolas which can still use as a fuel to gas operation without any problems. In this respect we also will inspect your furnace thoroughly to establish its efficiency and function. It is of no consequence to us whether it is one of our systems or was supplied by another manufacturer. Which of the various possible solutions ultimately makes sense will be determined individually for each customer. Naturally we are also available for you after the commissioning procedure for your new or modernised cupola furnace. For example we can provide training courses and advanced training for your personnel, keep your system working correctly with regular service and maintenance work and also keep you up to date with possible modernisation options. 6 7
ENGINEERING GLASS LINING TECHNOLOGIES JObbING FOUNDRy FITTINGS AND valves DRAINAGE TECHNOLOGy 10.09 Subject to technical changes and printing errors. Kuttner North America 211 N. Franklin Düker Street, GmbH PO & Co. Box KGaA 343 Port Washington, WI 53074 Würzburger Straße 10 Phone D-97753 +1 Karlstadt 262 284 4483 /Main Phone Fax +1 +49 262 9353 284791-235 4483 Fax +49 9353 791-175 www.kuttnerna.com CokelessCupolas@KuttnerNA.com Internet: www.dueker.de E-Mail: info.engineering@dueker.de