Heat-exchange system for coal-saving device

A coal economizer heat exchange system includes a coal economizer, several pieces of heat equipment which are connected by pipes in parallel, a water supply heat booster, a first pipe connected with the water supply heat booster outlet and the economizer inlet, a second pipe connected with the economizer outlet and all the heat equipment inlets and a third pipe connected with all the heat equipment outlets and the water supply heat booster outlet. The inlet of the water supply heat booster is also connected with a boiler supply pipe and the supplied water is used as the intermediate heat carrier to exchange heat in an open way between the economizer and heat equipment. The utility model, by utilizing the high-temperature water from the outlet of the economizer (low-temperature section) to preheat the low-temperature supplied water, can preheat several pieces of heat equipment at the same time; in this way, the economizer can be prevented from low-temperature erosion and the investment can be reduced. Moreover, after the economizer (low-temperature section) absorbs heat, the boiler can distribute and use the heat in a flexible way according to need. In addition, because the economizer is working under a state of no low-temperature erosion, the service life is long and the maintenance cost is low.