25-01-2013, 02:25 PM
VISAKHAPATNAM STEEL PLANT – RASHTRIYA ISPAT NIGAM LIMITED
1VISAKHAPATNAM STEEL.pdf (Size: 54.99 KB / Downloads: 50)
INTRODUCTION
Rashtriya Ispat Nigam Limited (RINL) is the corporate entity of Visakhapatnam Steel Plant. The
steel plant is located 26 km south of Visakhapatnam city. The plant has a capacity to produce
2.656 MT (million tones) annually of saleable steel of which 2.410 MT is finished steel. The
product profile of the plant comprises of wire rods, reinforcement bars (rebars), angles, channels,
beams, squares, billets and blooms. The product profile also includes basic grade pig iron,
granulated slag, coal chemicals and other by products. The plant also exports power to AP
Transmission company from its captive power plant. The monetary value of the total energy
consumption of main inputs averages Rs. 13,913 million (US$ 323 million) which accounts for
40 % of the manufacturing cost. The specific energy consumption during this period was 6.26
Gcal/ ton of Crude Steel. The commitment to energy conservation is reflected in the energy
policy of RINL where in it is committed to reduce specific energy consumption by 1% per year
up to 2010 AD.
The company has a thermal power plant for captive power generation. The thermal power plant
has five boilers, each with foreign materials like broken fill, debris largely due to heat transfer
area fouling because of turbid water. This problem was tackled by a new and innovative method
involving bullet shot cleanin g of the condenser tubes of TG-1 and TG-3 to facilitate vacuum
improvement. This option on implementation resulted in the annual energy savings of around
19.55 million kWh worth Rs. 3,265 lakhs (US$ 759,302). An investment of Rs. 10 lakhs (US$
23,256) towards rubber shot blast cleaning was paid back in less than a month and this measure
resulted in annual GHG reduction of 17,460 tons of CO2/year.
RESULTS
Assumptions and calculations behind the results are:
TG 3 Generation: 60 MW
Steam flow to the turbine: 270 tph
Heat rate : 2600 kCal/kWh
Coal Calorific Value: 2980 kCal/kg
Condenser Vacuum: 0.89kg/cm2 (Eqvt. Back pressure - 0.11 kg/cm2
abs)
Difference as additional work available through the turbine for the same input: 7.9 kCal/kg
steam (Enthalpy at 0.27 kg/cm2
(abs)- less Enthalpy at 0.11kg/cm2
(abs))
Additional power generation: 2232 kW (= 270 X 1000 X 7.9 / 860 X 0.9 Turb. Eff.)