The production from the biggest blast furnace of SAIl’s flagship unit Bhilai Steel Plant (BSP) – Blast Furnace-7 (BF-7) has started on Friday after a major repair, a BSP Press release informed.
The BF-7 that was put down for capital repair on May 15, 2017 for stack coolers modification job, has a capacity of producing 4,000 tonnes of hot metal every day, a testimony of the true Bhilaian spirit of converting all adversities into opportunities. This repair would increase BSP’s hot metal production from BF- 7 to more than 4,000 Tonnes/day while CDI (coal dust injection) injection can be increased to 120 kg/THM (per tonne of hot metal) which would reduce coke rate by 50 kg/THM, as a result of which per tonne hot metal production cost to decrease significantly. This would enable BSP to utilise its full potential of the largest blast furnace, it informed.
Major repairs that were undertaken in BF-7 included introducing copper coolers in S-3 and S-4 rows; changing of all the coolers of S-3 to S-7; changing of complete set of ceramic liners of receiving hoppers and material bins; changing of Dumping device of both sides; changing of complete set of TEGA liners in all the weighing hoppers; installation of de-fuming system in cast house and installation of new Mudgun and Drill Machine; modification of cooling circuit from single to double; overhauling of slag granulation plant (SGP); changing of Stove no 1 & 2 skin layer; changing of cooling flanges of Hot Blast Valve changed; and repair of GCP annular gap element. BF 7 Control Room has also been modernised.
At the blowing-in ceremony of BF- 7 , BSP CEO M Ravi congratulated the entire team involved in executing the capital repair.
The CEO was accompanied by ED (Works) TB Singh, ED (Projects) AK Mathur, General Managers and senior officers of the Plant.
The beginning of this financial year saw the launching of strategies which were sure to bear fruits and bring stability over long term. Since beginning of this financial year, restricted availability of coke had put BSP in a tight spot. Coking coal prices went very high due to disturbance in imported coking coal supply from Australia resulting into restricted production of coke from BSP’s coke ovens. This compelled BSP to regulate hot metal production also. As a result, the generation of Coke Oven gas and Blast Fce (BF) gas during production of coke and hot metal, respectively also went down. CO & BF gases are used as fuel in our coke oven batteries, boilers and furnaces of all the mills.
Hence, production of all the mills was regulated and brought down as per the scenario created due to imported coking coal crisis.
Approaching the crisis with a determination to perform, BSP proceeded with a firm strategy of planning for massive repair, focusing more on productions of value added products like rails and boiler quality and high tensile plates and concentrating on techno-economics parameters for maximising productivity from limited facilities.
In line with SAIl’s strategy of producing value-added steel that fetch higher NSR, Bhilai Steel Plant has used the repair time of BF 7 as an opportunity to focus on producing more of value added steel grades and less of the garden steel grades/variety and at the same time has undertaken large scale repairs to improve the health of other vital equipment which had been delayed in the past due to various reasons.
Besides the large scale repair of BF-7, the repairs of other vital equipment include repair of all the sinter machines of SP 2; Installation of new cooler and upgradation of automation system at sinter machine-1 of SP-3; Repair of Hydraulic main of coke oven battery-4; and Revamping of Wagon Tippler-2 used for coal unloading.
The focus on production of value added products like rails and boiler quality and high tensile plates has resulting in best monthly production of dispatch of rails and highest production of blooms for rail making. Ever Best Apr-Aug’17 performance have been recorded since inception in Hot Metal Production at BF-1, Production of Cast Blooms, Production of BQ Plates, Production & loading of UTS-90 Rails including long rails, and CDI Rate at BF-6 (Kg/THM).
With BF-7 under repair, thrust was given on improving productivity of other working furnaces. Blast Furnace No 1 recorded best ever monthly production of 61,600 T of hot metal with BF productivity of 2.3 T/M3/D while 76,370 T of hot metal from BF-4 have been recorded in Aug’17. In BF-6, CDI rate of 112.2 Kg/THM & BF productivity of 1.984 T/M3/D during Aug’17 are also the best ever monthly performance.
Improvement registered in techno-economic parameters for maximizing productivity from limited facilities include consistent quality in production of iron ore fines from BSP’s mines at Dalli & Rajhara; Stacking discipline improved at Ore Handling Plant (OHP) to reduce variation in quality of ore fines being supplied to sinter plants (SPs). With better stacking discipline and existing flux, and without iron ore fines from RMD, better quality material is being provided to SPs resulting in improvement in Sinter quality. Sinter chemistry was optimised and free lime was reduced by 1%.
All these efforts have culminated in massive improvement in BSP’s performance. Percentage content in sinter has improved. Slag rate at blast furnaces reduced and Blast Fce productivity has improved. Average coke rate has reduced to 488 Kg/ THM from a level of 508 Kg/THM. Coal Dust Injection (CDI) rate has improved to around 47 which is the highest average CDI at BSP. Daily hot metal production from BF-6 was more than 3000 T during August 2017 - improving significantly from a monthly average production level of around 2200 T / day.
In the month of August 2017, the Plant produced around 3.8 lakh Tonnes of hot metal with only six furnaces working. On the other hand, thrust has also been to reduction in inventory. large volume of cold ingots lying for quite long has been consumed during FY 17-18. Sale of secondary products was also maximized, with highest total cash collection from sale of secondary and by-products registered in a month so far.
With all these efforts BSP has successfully converted the challenge posed by scarcity of imported coking coal into a productive opportunity. Even with reduced production with respect to annual business plan (ABP), BSP saw commendable financial performance during the period. Thus even with reduced production BSP could enhance its profitability by 520 % over CPlY. This has enthused the Collective of BSP and they are ready to take on bigger challenges.
With blowing–in of Blast furnace-7 and startup of new BF 8 scheduled in September 17, BSP’s performance will touch greater heights and will enable the Plant to play its vital role in the turnaround of SAIl, it informed.