The technology is a practical energy economizing one which makes it possible to raise efficiency of heat producers and heat exchangers by recovering heat energy of waste gas from heating furnaces and boilers and reusing it in combustion process.

The existing waste heat recovering devices such as multitubular and tubular heat exchangers have not been widely used for a series of drawbacks such as low efficiency and high production cost.

The institute succeeded in developing a new kind of heat exchanger by combining multitubular one harmoniously with tubular one.

The new combination heat exchanger can heat air to 200-350 degrees centigrade.

A factory has introduced the combination heat exchanger into a heating furnace to warm combustion air up to 280 degrees centigrade, thus increasing the combustion efficiency considerably compared with the existing ones while economizing a large amount of oil.

The technology, the economic effectiveness of which has been proved by the users, was highly appreciated in the 24th National Scientific and Technological Festival.