Air Preheaters, Heater Type : Metal heating core

Air Preheaters (APH) is the Shell and tube type Heat Exchangers used for preheating the air which is fed to the boiler or furnaces/kilns for combustion of fuels. Its primary objective is to extract the waste heat from the flue gases leaving the boiler.

Thermodyne Engineering Systems manufacture Air Preheaters and are given as a standard side accessory along with the main equipment – Boiler, in a Packaged Type Boiler, Combi Boilers.

For generating fire in a boiler furnace 3 main ingredients are needed: Fuel, Air and Ignition. Air is used in a Boiler for combustion of fuel. Based on the stoichiometry calculation, right quantity of air along with excess air is fed into the boiler furnace for the combustion of fuel. Generally, fuel fed to the boiler is at normal room temperature and for combustion of fuel to take place; the temperature of the fuel is increased from its room temperature to ignition temperature. So to increase the efficiency of combustion process as well as a boiler, hot air is fed to the furnace for the combustion of fuel.

We manufacture different type of air preheaters:-

• Shell and tube type single pass air pre-heaters
• Shell and tube type dual pass air pre-heaters
• Finned tube air pre-heaters

Air Preheaters have a shell and tube type construction where exhaust heat from the flue gases is transferred to the air when they come in indirect contact with each other.

Air Preheaters consist of a shell where tubes are arranged in a square or triangular pitch and are welded to a tube plate. Depending upon the type of operation and ease of cleaning, flue gases and air can be allowed to travel either shell side or tube side interchangeably.

Thermodyne Boilers finned tube air preheaters are designed to maximize the efficiency by increasing the heating surface area without increasing the space requirement.

Thermodyne Engineering Systems manufacture air pre-heaters that are tailor-made to suit the customer’s requirement. Our Air Preheaters are designed in both 1 and 2 pass for both flue gases and air to extract maximum heat from the flue gases.

We manufacture air pre-heaters for wide capacity range and can satisfy the various fuel requirements of a customer such as:

• Wood
• Coal
• Husk
• Bagasse
• Petcoke
• Light Oil and Heavy Oil

• 2 pass design to extract maximum waste heat from flue gases leaving the boiler.
• It is used to extract waste heat from the flue gases leaving the boiler exhaust thereby increasing the efficiency of a boiler by 2-3 %.
• It is used to preheat the fuel which further increases the boiler efficiency.
• Payback time is less.

• Adding and equipment or accessory in the path of flue gases increases flue gas pressure drop down the line, so the size of Induced Draft Fan increases.