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Case study

Energy audit result of Formosa Ha Tinh Steel Corporation

19/09/2019

Formosa Ha Tinh Steel Corporation is a branch of the Formosa Plastics Corporation, Taiwan.  It is the investor of the Son Duong Iron Steel and Port Complex with the total investment of $10 billion.
Main products of the enterprises are hot-rolled bands and rolled steel wires which are exported to Thailand, Indonesia, Philippines,…
Energy use situation 
Currently, electricity and coal are two main types of energy used for the entire production process of the company. 
The electricity use situation of the company in 2018 is as follows: 
Energy efficiency potential 
The blast furnace No. 2 of FHS has operated since May 2018 and uses advanced energy-efficient technologies such as: TRT generator from the blast furnace peak pressure system, hot air furnace reusing excess heat, steam recovery system of converter and rolling line, coke dry quenching line recovering heat to generate electricity. It consists of two units of capacity of 36MW/unit.
FHS Company has set up an energy management board that will continue to discover energy efficiency potential of the company.
After the energy audit conduction, proposed energy efficiency solutions can help FHS save 5,073 tons of coal and 1,588.4 MWh of electricity annually, equivalent to USD438,431 accounting for 1.2% of its total energy consumption cost.
Particular energy efficiency solutions 
6 energy solutions are found during energy audit period including pump system improvement, air Compressor system improvement, high efficiency crusher application. 
Solution No.1: Using Water Level Control for Pump 81P002A/B
Real situation 
Pump continuously operates in low load state. In order to adjust the level of the tank by 50%, it is necessary to control the valve opening mode. The actual flow rate of pump is smaller than the designed one, leading to waste of electricity. 
Expected output 
When the tank reaches 80%, the pump will turn on automatically. When the tank level reaches 20%, the pump will turn off automatically. It will reduce electricity loss.
Energy efficiency results
Electricity savings: 10,264 kWh/yearInvestment cost: No requirement  
Cost savings: $718/ yearPayback period: -
Solution No.2: Using Smaller Impellers to Match the Demand for Cooling Water Pumps
Real situation 
The actual cooling flow rate is lower than the designed flow rate. 
During the pump's operation, the flow rate is always adjusted by setting the valve opening ratio by 50% leading to electricity waste. 
Expected output 
The use of the smaller impeller which is appropriate to the actual flow rate and the fully open valve can reduce electricity use.
Energy efficiency results
Electricity savings: 849,000 kWh/yearInvestment cost: $12,330 
Cost savings: $58,430 /yearPayback period: 0.2 year
Solution No.3: Move the air compressor inlet to the outside to reduce the inlet air temperature at the rolling mill
Real situation 
The air compressor operates making the temperature of the room higher than  that of the outside. High temperature of the inlet air leads to high energy consumption of the air compressor. 
Expected output 
Move the air compressor inlet to the outside can reduce the inlet air temperature and energy consumption of the air compressor. 
Energy efficiency results
Energy savings: 5,413,329 kWh//yearInvestment cost: USD90,000 
Cost savings: USD28,993/yearPayback period: 3.1 years
Formosa Ha Tinh Steel Corporation is one of 10 enterprises entitled to energy audit implementation within the framework of the Project for Promoting Investment Market for Energy Efficiency in Industrial Sector in Vietnam, funded by the Korean Government through Korean International Cooperation Agency (KOICA). The energy audit was conducted from December 3, 2018 to December 28, 2018 by the Energy Conservation Research and Development Center (ENERTEAM) in cooperation with Korean energy experts. 
Ngoc Diep