In response to significant increase in energy consumption caused by low-grade waste heat and energy waste in coal-fired power plants

a 350 MW unit is selected as the research object

the Ebsilon software is used to model and simulate different deep recovery schemes for low-grated waste heat and residue. The operating data of the unit under two schemes of “organic Rankine cycle(ORC)” and “Heater” are calculated. The energy consumption characteristics

revenue characteristics and differences are analyzed

and the mechanism and optimization plan for deep recovery of waste heat and energy are obtained. The results show that

the energy consumption characteristics of the unit improve significantly under both schemes

and the “heater” scheme has lower energy consumption. As the organic working fluid flow rate increases

the power generation of the ORC system gradually increases

but the thermoelectric efficiency of the ORC system gradually increases at first and then tends to stabilize and has a downward trend

with a range of 6.94%～7.75%. The organic working fluid flow rate has a relatively small effect on circulation efficiency of the ORC system. Both schemes are technically and economically feasible. The “ORC” scheme can bring direct electricity benefits to the power plant

while the “Heater” scheme is slightly more economical.