Fire Side Additive Furnace Powder

Fire Side Additive Furnace Powder

The primary aim of combustion is to obtain maximum amount of steam from each unit of fuel. But impurities in fuels and operational problems are limitations to achieve maximum output from burned fuel.

The impurities in coal can lead to formation of slag in boiler furnace, can leave the clinkers on the fuel bed and the presence of Sulphur can lead to the cold end corrosion.

It is possible to improve the combustion of fuel and reduce un-burnt carbon in the ash.

A fireside additive plays an important role in complete combustion of fuel along with a control on corrosion deposits, slagging clinker formation, reduction in air borne pollution emission as well as inhibition of fouling.

Our Multipurpose Solid Fuel Additive is a free-flowing powder, designed primarily for treating coal, wood and other solid fuels.

It acts as a combustion catalyst and thereby loss due to unburnt fuel gets minimized, resulting in improved combustion efficiency.

It has an anti–fouling agent that helps to keep heat transfer surfaces clean and thus improves the steam generation for same heat transfer area. Hard clinker is softened and the tendency of hard clinker formation is reduced, thereby helping in reducing boiler maintenance, while providing easy cleaning and also increases the boiler availability for long term operation.

This results in smoke free combustion at lower excess air levels and improved fuel economy.

What is the Process of Combustion?

  • Complete Combustion: C + 02 → CO2 (Carbon Dioxide)
  • Incomplete Combustion : C + 02→ CO (Carbon Monoxide)
  • C (Unburned Carbon)
  • Corrosion due to Sulphur Contents : S + O2 → SO2 →SO3 + Moisture (H2O) → H2SO4
  • Mineral Salt Impurities produce Slag : Forms Oxide
  • Clinker due to Silica Impurities : Forms Silicates

What are the Problems in Combustion Process ?

  • Incomplete Combustion
    Fuel burns in presence of oxygen to form Carbon Dioxide but a part of this fuel forms Carbon Monoxide and some remains as Unburned Carbon.
  • Slag Formation
    During the combustion process as the temperature rises molten fly ash particles adhere to relatively cool furnace walls, steam generating tubes and form a hard shiny layer known as slag.
  • Clinker Formation
    The Unburned carbon rises up the chamber and gets entrapped in molten slag to from a hard deposit called clinker.
  • Corrosion
    Oxides of Alkaline like Sodium, Potassium, Iron, Aluminum form sulphate with SO3 present in flue gas. These are very corrosive at high temp on metal surfaces.
  • Cold End Corrosion
    When Moisture from Fuel (H2O) reacts with SO3 flue gas in the chamber it forms H2SO4. This gets condensed in Air Pre-Heater, Economizer and Stacks to cause heavy blockages as it traps large quantity of fly ash.
  • Acid Smut Formation
    this is a result of sulphuric acid coated with soot and fly ash particles being emitted from stack

Why to Use Additives with Solid Fuel?

  • During the burning process our additive acts as a combustion catalyst by producing nascent oxygen, which boosts the combustion of carbon which reduces the formation of Carbon monoxide and Unburned Carbon.
  • Almost all Fuels have ash melting point in the range of 9000C to 16000C, thus impurities burn with carbon to form slag and clinker. Our additive reacts with the impurities like magnesium and aluminates’ compounds to form a spinal compound which is very easy to remove powdery deposit and has a melting point of more than 38000C. Raising the melting temperature of major impurities in the furnace inhibits the fouling of the furnace.
  • Our multipurpose fireside additive reacts with acids like H2SO4 and acts as a neutralizing agent to reduce the corrosion caused by acids to the chamber.
  • Our Additive does not allow the impurities that melt and form slag or clinker to sinter on to the Furnace, making the cleaning process easy.
  • Our additives also help in reducing the existing surface slag or clinker formed on the walls over years of use of the furnace.

Advantages of Using Additives

  • Complete Combustion of Fuel
  • Reduced Slag & Clinker Formation
  • Minimizes Corrosion & Cold Corrosion
  • Reduces Acid Smut Formation
  • Decrease in Unburned Carbon in Ash
  • Reduces Fuel Consumption
  • Increase in Furnace Efficiency
  • Decreases Particulate Matter from Stack
  • Forms Reflective Coating on Furnace Wall
  • Decreases the Radiant Energy Absorptio

Parameters to be Monitored

  • Carbon Dioxide
  • Unburned Carbon in Ash
  • Furnace Temperature
  • Particulate Matter from Stack
  • Stack Temperature
  • Slag & Clinker Deposits


Start with an initial dosage of 1 kg of additive for 4 ton of coal. After a Month dosage should be adjusted according to the performance of the additive. If smoke persists, increase by 0.5 kg per 4ton of coal for another month. If smoking stops, decrease by 0.5 kg per4ton of coal. To get the best performance of the additive, a regular dosage of the additive with as per the addition of coal is to be maintained.


Standard Packing: 50 KG HDPE.

Method for Application

Method A (For Manual charging of Fuel)
Add the fireside additive by manually charging through Fire Door / Inspection Door Point in furnace. For best results ensure the additive spreads over the maximum area of the solid fuel and covers the complete furnace.

Following precautions should be taken during manual charging of fireside additive

Standard Packing: 50 KG HDPE.


1) keep the Damper opening at minimum level during application.
2) Use soot blowing facility after chemical application.
3) If Force Draft is experienced put off the fan during dosing of chemical.
To be dosed directly into combustion zone once in a day or hourly as a Direct dose.

We have a wide range of Solid Fuel Additive, designed primarily for treating almost all types of solid fuels like coal, wood, bagasse, biomass and other solid fuels.


UNICHEM-Fs 30 is a versatile liquid phase combustion-monitoring chemical/fuel additive for liquid fuel such as furnace oil, LDO, LSHS etc. These products are contains dispersant, anti fouling agent along with advanced combustion catalyst for liquid fuel to improve boiler performance.

Use of heavy fuel oils in industrial furnaces is known to produce a host of corrosion, shoot deposition and environmental related problems. Severe corrosion in hot and cold zones of the furnace and emissions of obnoxious gases, particulates and acid smut to the atmosphere, shoot deposition, poor efficiency, nozzle choking, shoot rain are a few to name which will cost millions by way of forced shut downs and unscheduled maintenance, besides creating environmental pollution. A cost effective solution to mitigate some of the above problems is the use of chemical fuel additives. The effectiveness of chemical additives in heavy oil fired boilers is site specific and requires testing of additive in the boiler under actual operating conditions to optimize the additive regime to obtain the maximum gains.