Design, development and installation of a system for addition of oil–water emulsion on coal blend at coke oven, Durgapur steel plant

Abstract

especially during the monsoon period, because of poor uidisation as a result of a high moisture content in the A selective crushing unit was installed at the feed coal. Durgapur Steel Plant (DSP) of the Steel Authority ofIn the selective crushing unit, coal is fed from silos to India Ltd (SAIL) in March 1997 for better coal primary crusher units through two conveyors numbered preparation and improvement in coke quality with C14-A and C14-B. The system was designed for a maxirespect to M10, coke reactivity index (CRI) and coke mum moisture level of 8•5% in the feed coal. During the strength after reaction (CSR). However, the monsoon, the moisture level in coal increases beyond this selective crushing performance deteriorated level, leading to problems such as jamming of chutes and especially during the monsoon period, because of classi ers. Because of jamming, sometimes the classi ers poor fluidisation of coal due to a high moisture are bypassed in order to supply coal to service bunkers level in the coal charge. In the selective crushing continuously. This causes deterioration of coal crushing and unit at DSP, coal is fed from silos to primary in turn coke quality. crusher units through two conveyors, namelyAddition of an oil-water emulsion to a moist coal charge C14-A and C14-B. The system is designed for a not only increases the bulk density of coal1-3 but also maximum moisture level of 8•5% in the coal charge.improves the handling and the ow properties of the coal During the monsoon period, the moisture level of charge. This helps in producing coke of uniform and the coal increases beyond 8•5%, leading to improved quality and results in higher throughput from problems such as jamming of chutes and the ovens. Spraying an oil-water emulsion on a coal blend classifiers. Sometimes the classifiers are bypassed improves the owability of the coal by reducing its angle in order to supply coal to service bunkers of repose. The R&D Centre for Iron and Steel (RDCIS), of continuously. This causes deterioration of coal the Steel Authority Of India Ltd (SAIL), Ranchi, India has crushing and in turn coke quality. Addition of an designed and installed a system for oil-water emulsion oil-water emulsion to the coal blend reduces the spraying over a coal blend for the rst time at DSP. angle of repose and improves the bulk density ofWater is used along with oil for emulsi cation and as coal charge improving its flowability. It also allows a carrier of oil to increase the cover of bulk mass over a more coal to be charged per oven leading to an wide surface area of the coal feed. This gives economies in increase in oven throughput. The Research and the use of oil. The owability of the coal charge is improved Development Centre for Iron and Steel (RDCIS), to a great extent with a very small proportion of oil in the SAIL has designed and installed a system for oilemulsion. Further, a water-oil mixture is safer in respect water emulsion spraying over coal blend for the of re hazards. first time in DSP. The system has beenExperiments h...