Study On Thermal Characteristics And Economics Of Tower Solar Energy-assisted Oxygen-enriched Coal-fired Unit

The realization of energy cleanliness has become the trend of global energy.China’s solar energy resources are abundant,and China’s solar energy resources are very rich.Solar thermal power generation technology has the advantage of zero consumption and zero pollution,and has an important strategic position in the future energy structure.In China’s coal-based power structure,the combination of solar energy and coal-fired units not only increases the effective use of renewable energy,but also reduces pollutant emissions and fossil fuel consumption.Compared with trough solar energy,ratio,high heat collection temperature,large system capacity,and large-scale grid-connected power generation.The tower solar collector system is integrated into the oxygen-rich coal-fired generating unit.The use of heat generated by solar energy to replace part of the heat generated by fuel combustion to reduce coal consumption,while also reducing pollutant emissions.This paper selects a 600 MW oxygen-enriched coal-fired unit in Inner Mongolia,based on the development and research status of tower-type solar-assisted ordinary coal-fired units,and proposes an integrated scheme of four tower-type solar-assisted oxygen-enriched coal-fired units according to the energy matching principle.The software Ebsilon professional simulates the steady-state thermal performance and analyzes the four integrated schemes to maintain.With the increase of the extraction ratio,the operating parameters,thermal characteristics and economical changes of the oxygen-rich coal-fired boilers.The simulation results show that after the steam extraction of the oxygen-enriched boilers,the smoke temperature of the flue of the heating surface will increase,and the temperature can be effectively adjusted after the flue gas recirculation is increased,thus ensuring safe and stable operation of the unit,but due to oxyfuel combustion.The coal unit is equipped with a flue gas waste heat utilization device.In order to ensure that the amount of flue gas after dedusting and dehydration can replace a part of the heat for replacing the four-stage low-pressure extraction,the cold flue gas after the waste heat of the flue gas is exhausted from the tail flue precipitator The maximum extraction volume should not exceed 25%.In order to make the flue gas recirculation and temperature regulation more obvious,the maximum flue gas recirculation ratio is at least 25%,so the flue gas recirculation ratio is selected as 25%,and the corresponding total flue gas circulation is corresponding.The rate is 8.48%.When the flue gas recirculation rate is kept constant,the boiler efficiency of case1 will decrease with the increase of the extraction ratio,and the maximum reduction will not exceed 0.04%,but the boiler efficiency of case 3,case 2 and case 4 will increase,and the maximum will not exceed 0.02%.The solar-assisted oxygen-enriched coal-fired boiler can effectively reduce coal consumption for power generation,The maximum coal saving is 40.5g/(kw?h).The four integrated schemes proposed in this paper have made economical leveling power cost analysis.The cost analysis results show that the photothermal pricing currently defined in China has great economic competitiveness and development potential,and has good returns.Capacity and low investment costs.