1. Energy and cost saving.  It uses the exhaust gas during the combustion of heat transfer oil boiler
2. Convenient and easy to operate. The waste heat exchanger does not need manual operation and energy consumption, only need the electricity of one water pump.
We’d like to take 4 million Kcal heat transfer oil boiler as an example. The flue gas temperature generated by heat transfer oil boiler is about 680°F-752°F,(flue gas temperature is oil temperature+176°F--248°F). Normally this part of flue gas directly discharges into the environment through dust collector and ID fan. This exhaust way has below disadvantages. 
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