A Journey Towards Improving Tuyere Life

Tuyere is one of the critical components of blast furnace. The function of tuyere is to supply hot air and fuels like pulverized coal inside the furnace. In doing so, tuyeres get exposed to severe thermal conditions, hot metal contact and abrasive environment. Tuyere failure contributes to major part of mechanical breakdown in the furnace leading to immense production loss. This work focuses on a continuous journey to improve the life of tuyere. The prime effort goes into understanding the zone of tuyere failure and subsequently modifying the design in terms of cooling enhancement and improving wear resistance of material. Fibre Bragg grating fitted tuyere has been manufactured to measure temperature and predict heat load on tuyere. These inputs are used in numerical model to evaluate cooling performance. It has been found that existing tuyere designs seem to overlook the criticality of boiling which may deteriorate cooling performance. Effort has been concentrated to modify the design of cooling circuit to suppress boiling. Properties of existing protective architectures have been determined, and subsequently effort has been devoted to enhance the wear resistance of the material by putting refractory protection. All these combined efforts have enhanced the service life of tuyere by 20%.