Frequency control of the roasting machine fan performance at the Central GOK

Central Mining and Processing Plant is part of Metinvest Group and is one of the country’s largest producers of raw materials for the steel industry.

As part of the plant’s modernization, one of the stages of work was the introduction of a frequency drive for the D-4B industrial blower (1600 kW, 993 rpm, 6 kV), which provides air supply to the OK-324 firing machine. This project was carried out by Dalgakiran Compressor Ukraine in cooperation with YASNO Efficiency.

Qualitative improvement of equipment operation

The main task was to install a Hiconics high-voltage frequency converter (HVFC ) and related equipment that would ensure uninterrupted operation of the fan and, at the same time, significantly reduce energy consumption. This task was completed in full.

Based on the existing power supply and control circuit, it was decided to include the HPV control system in the existing PID controller link based on the Miktrol MIK-25 microprocessor unit, namely HPV, high-voltage bypass switch cabinet and peripheral relay automation. This way, the old fan slide control circuit was supplemented with a functioning unit as a hot standby. The advantage of this modernization, in addition to a significant reduction in electricity consumption and automatic operation of the D-4B fan, was the removal of the old control system to the reserve.

Energy efficiency is the key to stable operation of the enterprise

Before the HPV project was implemented, the volume of air supplied by the fan was regulated by partially blocking the air duct (changing the position of the guide vanes). Moreover, it was performed manually by the operator. At the same time, the fan speed was constant and the consumption of electric energy, regardless of the needs of the firing furnace, was maximized.

The installation of the new equipment reduced the speed of the fan motor to 600 rpm, and the expected economic effect of the implementation is more than 50%. According to the estimates of the CGOK specialists, the use of VFDs will save about UAH 4.5 million per year. In addition, the use of frequency control ensures a smooth start-up of the fan motor and, as a result, reduces its wear and operating costs.

Project manager: Anton Tkachenko

Project manager: Alexander Dyadyushkin