Energy Saving and Process Optimization in a Conventional Hot Strip Mill by Application of the Latest High-Efficient Descaling Technology

摘要

The paper describes the converting to a new generation of descaling nozzles in a conventional hot strip mill for steel. There are descaling stations behind the reheating furnace, on the roughing mill stands and in front of the finishing mill. Before the converting, there had been three high pressure pumps in operation to supply the descaling stations. The new descaling nozzles had been tested first in the finishing mill descaler with good results. There were considerable water savings without compromising the descaling effect and the material surface quality. After a successful test, the remaining descaling stations had been converted accordingly. The overall water savings was approx. 20%, which allowed shutting off one of the three high-pressure pumps. Electrical energy saving amounts to 9,300,000* kWh/ year. At the current energy costs this is equivalent to 2,100,000 TL / 641,700 EUR**. Additional advantages are seen such as reduced material cooling and the lower wear of the components of the whole high-pressure water hydraulic system.* :Daily saving of 30,000 kWh. One year is considered as 310 days.Data acquired by an energy analyzer at site.**: Earnings calculated using the cost of electricity as 0.069 Euro /kWh.