Rajnish Kapur, Business Head (Grey Cement Division), JK Cement.
Designing common material handling systems for AFRs is a major challenge apart from the dysfunctional effect of AFR on refractories. Systems better than hot disc, which is able to take all AFRs are welcome. However, looking into the high initial investment cost, government agencies should provide incentives in some form, says Rajnish Kapur, Business Head (Grey Cement Division), JK Cement. Excerpts from the interview...
Brief us on the steps initiated in the use of AFR by JK Cement at its plants.
As a responsible group, we are looking at all opportunities to increase the use of AFR in our plants. Currently, we are using AFR viz, carbon, plastic, ETP sludge, pyrolysis oil and chemical gypsum in our cement plants in Rajasthan and Karnataka. We are also using additives like fly ash and slag at our plants. A separate agro waste feeding system has installed for firing agro waste in pre-calciner at our Mangrol (Rajasthan) plant. Carbon black firing started in the kiln and calciner along with the existing fuel firing system at all our plants. Various trials have been done to use other wastes like spent oil, spent grease, mustard husk billets etc. For the use of AFR, we are also installing AFR feeding system with our new line commissioned in June 2014 at Mangrol. TSR for Mangrol plant was 5.9 per cent in 2014-15 compared to 3.6 per cent in 2013-14. We are targeting 7-8 per cent TSR by 2017.
What are the technical challenges faced?
Presently, we are using AFRs, which can be fed in the existing system, may it be solid like ETP sludge and plastic or liquid like pyrolysis oil. The main challenges are consistent AFR-fuel mix ratio; homogeneous AFR with respect to feeding system designed and kiln configuration for stable operation. Designing of AFR handling system to accommodate different forms of AFRs viz, solid, liquid, powder, semisolid, etc, is another major challenge.
What were the challenges faced in terms of cost?
Investment cost: Due to different forms of AFRs viz solid, liquid, powder, semisolid, etc, the initial investment for system designing, erection and commissioning is on higher side.
Operational cost: Due to the pungent odour, feeding of AFRs become difficult and thereby proper storage and treatment of the AFRs become costly. The shelf life of AFRs is also an area of concern due to regulatory norms. For old cement plants, retrofitting of AFR systems is sometimes uneconomical.
With regard to hazardous material used, what are the challenges in terms of safety?
Due to the pungent odour, feeding of AFRs becomes difficult, thereby proper storage and treatment of the AFRs become imperative for effective handling. Else, the health hazards and risk to persons handling AFR shall increase.