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Is the boiler the same as the direct fired unit?

10 Jun 2022

Heating equipment is common in daily life and production, and there are many kinds and uses. Users often have many questions when selecting boilers. Do users often come to inquire whether the boiler is the same as the direct-fired unit? What's the difference?

 

Gas boiler takes natural gas, fuel oil, etc. as fuel, and releases heat energy through combustion, which is transmitted to the medium in the boiler, so that the temperature of the medium increases. After rising to a certain temperature, it outputs high-temperature hot water, steam or thermal oil, which is then sent to the production workshop through pipelines for production and processing.

 

The direct fired unit uses the heat generated by fuel combustion as the driving heat source to heat the lithium bromide solution in the generator, and the high-temperature lithium bromide solution heats the evaporator to produce hot water. The structure consists of a high-temperature generator, a low-temperature generator, a condenser, an evaporator, an absorber, a solution heat exchanger, a burner, an efficient full-automatic pumping system and an advanced microcomputer control system.

So are boilers the same as direct-fired units? The answer is no.

 

Difference between boiler and direct fired unit

What are the differences between boilers and direct-fired engines?

1. Function

The direct-fired unit can be used for cooling or heating and sanitary water, with a capacity of 1000KW, and can be used for domestic or commercial use. gas-fired boiler is used for heating and water supply. If it is used for cooling, it needs to be equipped with steam absorption chiller, and its capacity range is large. The heat supply of ZOZEN gas-fired boiler is 130t/h, which can be used for commercial and industrial heat and thermal power plants.

2. Different structures, different production requirements and costs.

The structure of direct-fired unit is complex, and the price of direct-fired unit with the same power is several times that of gas-fired boiler.

3. Thermal efficiency

The exhaust gas temperature of direct-fired boiler is 150-220℃, and the thermal efficiency is generally 70%-85%. The exhaust gas temperature of ZOZEN gas boiler can be lower than 60℃, and the thermal efficiency is over 98%.

4. Maintenance cost

Direct-fired unit not only costs water treatment, but also costs maintenance of solution. Lithium bromide solution has strong corrosiveness to metal, which can be restrained after adding corrosion inhibitor, but it can't be eradicated. In addition, there are many other reasons, such as poor vacuum of the unit, reduction or failure of corrosion inhibitor, deterioration of lithium bromide solution itself, etc. Therefore, it is necessary to regularly sample and analyze, and purchase adjusting agent when necessary.

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