Effect of Oxygen Enrichment on the Performance of a Rotary Furnace: A Harbinger to Ecological Sustenance and Pollution-Free Castings

Abstract

The iron foundries have been playing a vital role in the industrial development of India. The major problems being faced by iron foundries are restrictions on energy consumption by TERI and emission levels due to which majority of coal fired ferrous foundries in Agra have been closed by an order of the Hon’ble Supreme Court of India. The present state of foundries in Agra reveals that extensive research is necessary to develop an ecofriendly and energy efficient furnace. Therefore, A 200 kg capacity rotary furnace, have been designed and developed in DEI and studied for its technical feasibility, economic efficiency, energy consumption and emission levels. Lot of Experiments were conducted by earlier researcher with heat recovery unit, different fuels and their combination improved the energy requirements and reduced the emission levels but the levels obtained were not as per the required limits of TERI and CPCB. Looking so, a modified heat recovery unit, compact heat exchanger has been designed. Till now researcher has used circular nozzle with central holes but in our case we have used Reillo burners of the type RL/M70-190. Experiments are conducted with new heat exchanger and nozzle using LDO blended with jatropha. The furnace parameters are optimized experimentally and found that using Reillo burners of the type RL/M70-190, modified heat exchanger, rotating furnace at 1 RPM using 10–20% excess air and 400° air preheat, using 7.5–8.5% oxygen enrichment, emission levels are significantly reduced than CPCB limits and energy consumption is also reduced than permissible TERI limits. The operating cost is reduced by a significant amount and quality of the casting is also found excellent. Hence, use of rotary furnace with the above modifications will be a boon for the foundry industry of Agra and India at large.