PentoMag® | Additive for Coal Boilers
#Fight Coal Slagging and #Deposits in the Boiler

PentoMag® for coal boilers

Simply explained

Let’s talk about PentoMag 2550

Anti slagging additive for coal fired boilers.

PentoMag 2550 increases the fusion temperature of metals in fly ash.

Thus preventing that ash can stick to the boiler walls.

It changes the amorphous structure by forming friable crystals with low density.

Their removal will usually lower the maintenance

PENTOL assists you during the whole process

Consultation and engineering assistance

Dosing equipment installation

PentoMag supply

Emissions testing and combustion optimization

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Reduce ash slagging

Certain coals tend to form slag and sintered deposits in the combustion chamber of the boiler. The slagging effects leads to a reduction in efficiency of the plant and eventually the plant needs to be shut down for cleaning in short intervals. In extreme cases, deposits on super heaters can grow to a size of several hundred kg and severely damage boiler tubes when falling down. “Eye brows”, deposits forming around the burners, have a negative effect on combustion quality as they change the air flow around the burners. 

PentoMag 2550  increases the fusion temperature of metals contained in the coal, thus preventing that the ash can stick to the boiler walls. It changes the amorphous structure by forming friable crystals with low density.


Who needs PentoMag 2550?

If your plant suffers from one of these symptoms, PentoMag 2550 might be a possibility for you to optimize boiler efficiency:

  • Significant losses of production
  • Heat transfer problems
  • Boiler tripping
  • Damages at the bottom tubes

On the following pages we try to outline how PentoMag 2550 works and if it is suitable for your plant.

Action principle

Reduce slag density

There are 3 main factors that influence slagging in a boiler: Boiler design, coal properties and oxygen level of the combustion. Typically the operator has little influence on all 3 of them. The boiler design cannot be changed, coal properties are subject to the price politics of the enterprise and the choice of operating parameters like excess air is limited due to technical constraints.

PentoMag 2550 somehow eases the pressure on the operator, as it increases the bandwith of operation in the boiler.

There are 2 main working mechanisms:

  1. Increase fusion temperature of metals contained in the ash.
    Slags start to accumulate if the ash is in molten form. Once the process starts, it gets worse and worse due to the reduced heat transfer from gas to steam. By increasing the melting point of metal oxides in the ash, the ash remains dry and cannot stick to the walls.
  2. Change the structure of deposits.
    PentoMag 2550 changes the amorphous structure of the deposits to a crystalline structure. The advantage is a reduced density and friability of these deposits.

Sticky amorph structure

Without PentoMag® 2550 deposits are glassy, flowing with high density

Porous crystalline structure

With PentoMag® 2550 deposits are friable and lightweighted

Magnesium and Copper in a perfect balance

PentoMag 2550 is a combustion additive based on copper and magnesium.

Magnesium oxide has a great influence on fusion temperature of ash independent of the fuel source. Pentol carefully chooses raw materials with high activity to keep the dosing rate low and efficiency high. Compared to other active substances, magnesium oxide forms water soluble salts that are easy to remove.

Copper changes the structure of the already existing deposits from an amorphous to a crystalline structure and further increases the effect of the product.

Sophisticated manufacturing and stabilisation of PentoMag 2550 containing approx. 70% active substances enables application of very low dosing rates. Pentol recommends to start tests with 300 ppm and gradually reduce the dosing rate. Actual dosing rate is always adjusted according to coal quality, boiler design and practical experience during initial dosing period.
To properly evaluate dosing efficiency the cost of treatment per ton of coal is the key indicator rather than additive unit price.

Dosing skid

We adapt the dosing systems to your local operational conditions

Fully automatic dosing systems: precise, protected and easy to use.
Pentol develops and produces highly reliable dosing equipment specifically for its range of additives. The pictures below show a fully automated dosing skid for small and medium size boilers with a coal flow detector to adjust dosing rate.
The product is usually added to the coal before the mills.

A continuous dosing system with very high availability is key to every successful fuel treatment as any interruption of additive supply can lead to a temporary increase of deposits in the boiler.

The dosing system includes an ultrasonic level detector for the coal belt to turn dosing on and off. If signals from the conveyor are available they can be connected to the controller.

The dosing pumps, storage tank and unloading system are installed in a 20 feet container.


Higher availability

Just like the products of the PentoMag series designed for fuel oil, PentoMag 2550 has a strong influence on availability of the boiler and on maintenance cost. Pentol has clients in Europe, South America and China who rely on this technology to extend the time between scheduled shutdowns planed for cleaning of the boiler.

Increase of ECO-efficiency

Increase of ECO-efficiency

  • Reduced coal consumption
  • Improved thermal exchange rate

Reduction of operating costs

  • Better heat transfer
  • Higher boiler availability

Reduction of cleaning costs

  • Have fewer outages for cleaning
  • Shorter cleaning time
  • Ash is easier to remove

Ask our staff for a presentation or training.

Did we get your attention?

We would love to hear from you and discuss any questions you might have personally. Pentol has successful references in Asia, Middle East and Central America and we are proud to share them with you!


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ADDITIVE – PentoMag® for Coal EN


ADDITIVE – PentoMag® for Coal » RU