■ The boiler exit temperature with single-phase medium high heat-conducting oil as heat carrier, use of forced liquid circulation heat pump    Cycle, the energy delivery device to use a special heat boiler. ■ Advantages: in a closed loop circuit, less heat loss; pressure is low, the outlet temperature, safe and reliable; ■ because the fuel is different at the two structures. YLL-type fuel for the coal; WNS-based fuels to natural gas, oil. ■ boiler capacity of 700-7000KW.