Key Benefits

  • Meet environmental standards
  • Save energy
  • Reduce emissions of hazardous fuel particles
  • Improve ESP performance
  • Fuel flexibility

Electrostatic precipitator power supply with low emission guarantee

Since the late 1970s, we have been working to innovate energy efficiency and emissions standards at industrial production facilities by perfecting the Coromax pulse system

Today, the system has proven to be more effective and revolutionary than ever. The modern Coromax system can reduce hazardous dust emissions by 30 – 50% while significantly decreasing power consumption.
for even the smallest particles (below 0.1 µm), including mercury and other hazardous matters
Installed around the world including Europe, Asia and US
Proven patented technology with positive track record in coal-fired power plants and sintering plants

Save energy and reduce ESP emissions with the Coromax power supply.

Meet environmental standards

The Coromax pulse system is designed to meet the environmental standards of your industry and location. Our engineers will work with you to ensure compliance with the following environmental requirements:

  • BREF (Best Available Techniques (BAT) reference documents)
  • NESHAP (National Emission Standards for Hazardous Air Pollutants)
  • MATS (Mercury and Air Toxics Standards)
  • MACT (Maximum Achievable Control Technology Compliance)
  • CISWI (Commercial/Industrial Solid Waste Incinerators)
  • IPPC (Integrated Pollution Prevention and Control)
Save energy
Installing the Coromax system on your ESP will significantly reduce power consumption by as much as 60 – 80%, saving you both energy and money.
Reduce emissions of hazardous particles
In addition to cutting down on power consumption, the Coromax also reduces harmful dust outlet emissions by 30 – 50%, creating a safer work environment and minimising air pollution.
Improve ESP performance
A reduction in power consumption naturally leads to an improved and more efficient performance in your ESP, resulting in emissions that are cleaner and safer than ever before.
Fuel flexibility
The Coromax system will automatically adjust to variation in the process as well as to different kinds of coal/lignite. Due to the micro-pulsing and automatic adjustment of current, voltage and frequency, it becomes less sensitive to fuel changes.
FGD operation
Where wet desulfurization system is installed, there will be less maintenance and operation cost by installing the Coromax system. This, because there will be less particles entering the FGD system, which means less wear on cyclones, pumps and nozzles. Also dewatering system and waste water treatment will be improved. Furthermore, removing the particles to a minimum can have a stabilizing effect on the chemical balance of the FGD system, whereby less supervision and laboratory test is needed.

Achieve maximum efficiency in your electrostatic precipitator

Voltage range

The latest version of the Coromax pulse system available is the mk4. In contrast to previous models, this latest system features improved reliability due to its switching devices, which fall in the medium voltage range.


Coromax pulse systems generate a special voltage waveform in the ESP, which is characterised by a smooth base voltage superimposed by extremely narrow pulses. They are designed to capture high-resistivity dust, such as dust emitted by coal-fired power plants and steel sintering plants. High dust resistivity normally leads to high levels of dust emission from ESPs powered by transformer/rectifier (T/R) sets or switch mode power supplies (SMPS). With the Coromax mk4, these harmful emissions can be reduced by 50 %.


The base voltage for the Coromax mk4 can reach up to 60 kV, with a nominal pulse width of 75 µs and an amplitude of up to 80 kV, which allows for a total maximum peak voltage of up to 140 kV. The rated pulse repetition frequency is equal to 100 pulses per second (PPS).


  • The current can be controlled independently from the voltage by varying the frequency of pulse repetition. This allows the ESP to operate at a high-voltage level while maintaining a low current level and eliminating back corona.
  • Narrow pulses allow the ESP to reach higher voltage levels, improving the charging and collection of small particles.
  • These narrow pulses and the high-voltage levels cause a more intense corona discharge, which results in better current distribution inside the ESP.

Control unit

The Coromax mk4 is controlled by the EPCU, a specially designed microprocessor-based control unit. Using a proprietary and patented control strategy, the EPCU can optimally control the amplitude of the base voltage, the amplitude of the pulses and the pulse repetition frequency. An EPCU can also be used to control rapping and heating systems.


Advantages of the Coromax mk4

  • A high-voltage power supply system
  • A microsecond pulse system
  • Generates pulses up to 140 kV – improving migration velocity (w)
  • Very different from SMPS/high frequency or 3 phase systems
  • Avoids spark limitations
  • Avoids back-corona problems 

Easy installation

No need to change internal parts


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