Obiettivo To examine the application possibilities of a precalcination facility with circulating fluidized bed furnace in a cement plant in Port la Nouvelle/France. In the course of the project, the transferability of laboratory test results to a large plant with a daily capacity of about 1200 Ton/day is to be tested and demonstrated. A maximum annual energy substitution of 10,750 TOE fuel-oil by high-ballast solid fuel is to be expected at project level.To achieve through processing at medium temperature (850 deg. C) in reducing medium, volatilisation of potassium/calcium sulfate and chlorides and divert them from clinker fabrication cycle.The experted energy saving, compared to the existing classical by-pass, results from the evacuation of less gas and dust content at lower temperature for the same efficiency. Scheduled payback of the installation is 3.8 years.Certain technical results obtained during the course of the project are sufficiently encouraging to plan for the use of a fluidised bed precalcination systems in new cement works, and in fact two European patents have been registered.However, following difficulties due to the characteristics of the cement works hosting this project and the problems regarding the supply of raw materials (schistes of lower quality and higher price than expected), the economic viability of this particular application has been compromised. Due to difficulties with regard to installation, the specific energy consumption was, at 910 kcal/kg, 60 kcal/kg higher than the conventional process, and moreover an extra 6 kWh/Ton of electricity had to be used. Consequently, the installation was shutdown.On the other hand for new plants, improved integrated design would result in a successful exploitation of this technology which clearly has advantages:- at temperatures in the order of 850 C, a 98% decarbonation- considerable energy savings composed with a conventional plant- possibility of burning completely, either coal which is coarsed than that normally used, or low grade solid fuel (schiste).The new type of precalcination system - LCL process planned for this project is an expanding fluidized bed furnace with re-circulation, which should be particularly suitable for the combustion of high-ballast solid fuels. For a homogeneous raw meal fuel mixture and a fluidized bed temperature of about 900 deg. C., this fluidized bed permits almost complete combustion of the fuel with simultaneous deacidification of the raw meal by up to 98%. In order to achieve this high precalcination, approximately 75% - 80% of the fuel quantity is charged into the LCL section. Consequently the fuel supply to the rotary kiln is reduced accordingly.When first installed instead of a classical by-pass, due to lower gas extraction level the new equipment results in both investment reduction and energy savings. Programma(i) ENG-ENALT 1C - Programme (EEC) of financial support for projects to exploit alternative energy sources, 1979-1984 Argomento(i) 1.6 - INDUSTRY Invito a presentare proposte Data not available Meccanismo di finanziamento DEM - Demonstration contracts Coordinatore CREUSOT-LOIRE ENTREPRISES Contributo UE Nessun dato Indirizzo B.P. 303 92156 SURESNES Francia Mostra sulla mappa Costo totale Nessun dato
