Mixed heat exchanger is relying on cold and hot fluids in direct contact with the heat transfer, this heat transfer mode to avoid the heat transfer between the wall and both sides of the fouling thermal resistance, as long as the contact between the fluids is good, there is a greater rate of heat transfer. Therefore, wherever the fluids are allowed to mix with each other, mixed heat exchangers can be used, such as gas scrubbing and cooling, cooling of circulating water, mixing between steam and water heating, steam condensation and so on. Its application throughout the chemical and metallurgical enterprises, power engineering, air conditioning engineering and many other production sectors.

According to the different uses, the mixed heat exchanger can be divided into the following different types:

(1) Cooling tower (or cold water tower)

In this type of equipment, natural or mechanical ventilation is used to circulate the water that has been raised in temperature in production after cooling down to improve the economic efficiency of the system. For example, the circulating water of thermal power plant or nuclear power plant, the cooling water in the production of ammonia, etc., is cooled down and then recycled after the water cooling tower, and this method is widely used in the actual project.

(2) Gas scrubbing tower (or scrubbing tower)

In industry with this equipment to wash the gas has a variety of purposes, such as liquid absorption of certain components of the gas mixture, in addition to the clean gas dust, gas humidification or drying, etc.. However, its most widespread use is to cool the gas, and the liquid used for cooling is mostly water. Air-conditioning engineering widely used in the spray room, can be considered a special form of it. The spray room can not only cool the air like a gas scrubber tower, but also heat it. However, it also has the disadvantages of high water quality requirements, large footprint, pumps consume more energy: so, at present, in general construction, the spray room has been used infrequently or only as humidification equipment. However, in order to regulate humidity for the main purpose of textile factories, cigarette factories, etc. are still used in large quantities!

(3) Jet heat exchanger

In this type of equipment, so that the higher pressure fluid from the nozzle jet, the formation of a very high speed, low-pressure fluid is introduced into the mixing chamber and the jet direct contact for heat transfer, and together with the diffusion tube, in the diffusion tube of the outlet to reach the same pressure and temperature sent to the user.

(4) Mixed condenser

This kind of equipment generally uses water to condense steam by direct contact with steam.

Heat Storage Heat Exchanger

Thermal storage heat exchanger is used for thermal storage type heat transfer equipment. Solid filler inside, to store heat. Generally used refractory bricks and other fire lattice (sometimes with metal waveform band, etc.). Heat transfer in two stages. The first stage, the hot gas through the fire lattice, the heat transfer to the fire lattice and storage. In the second stage, the cold gas passes through the fire lattice and receives the heat stored in the fire lattice and is heated. These two stages alternate. Usually two heat accumulators are used alternately, i.e., when the hot gas enters one vessel, the cold gas enters the other vessel. Commonly used in the metallurgical industry, e.g., the heat storage chamber of a steelmaking flat furnace. Also used in the chemical industry, such as air preheaters or combustion chambers in gas furnaces, and regenerative cracking furnaces in man-made oil plants.

Regenerative heat exchanger is generally used for the media mixing requirements are relatively low occasions.