考虑光热电站及富氧燃烧捕集技术的电热气综合能源系统低碳运行优化

Low-Carbon Operational Optimization of Integrated Electricity-Heat-Gas Energy System Considering Concentrating Solar Power Plant and Oxygen-Enriched Combustion Capture Technology

针对传统机组的运行约束及环境污染问题,引入富氧燃烧捕集技术对燃气机组进行改造,配置含热回收器的光热电站实现热电解耦与辅助供能,并结合电转气设备、燃气锅炉等能量转换设备组成综合能源系统,提出一种电热气综合能源系统低碳优化方法。首先,构建系统架构,并建立富氧燃烧捕集机组的电碳特性方程与光热电站模型;其次,计及反应余热利用与氧气回收,建立电转气设备模型;然后,引入奖惩阶梯型碳交易机制以限制碳排放量,建立以系统运行成本最小为目标的电热气综合能源系统低碳经济调度模型;最后,进行算例仿真,由仿真结果可知,该方案可兼顾减碳效果与运行效益,不仅可以提高燃气机组的运行调节能力与电转气设备的运行潜力,提升系统的运行效益,而且可以有效降低环境污染与制氧能耗。

With the increasingly prominent contradiction between energy demand and environmental pollution,how to reduce carbon emissions from traditional energy sources has become a key issue for energy conservation and emission reduction.Carbon capture technology is one of the important technical paths to cope with climate change.The most commonly used carbon capture technologies are still the post-combustion capture technology and the pre-combustion capture technology.The post-combustion capture technology has the disadvantages of large footprint and low capture cost.The pre-combustion capture technology has the disadvantages of complex modification process and low technical applicability.As a new carbon capture technology,the oxy-fuel combustion capture(OCC)technology can effectively integrate the advantages of the above two carbon capture technologies and has a good application prospect.For this reason,the OCC technology is introduced to modify the gas unit and equips concentrating solar power(CSP)plant with heat recovery device so as to realize thermoelectric decoupling and auxiliary energy supply.With the energy conversion facilities like power to gas device and gas boiler to form an integrated energy system,a low-carbon optimization method of integrated electricity-heat-gas energy system is proposed.Firstly,according to the concept of low-carbon energy supply and multi-energy coupling,the structure of integrated electricity-heat-gas energy system is established.The feasibility of combined heat and power operation of CSP plant is analyzed,and the mathematical model of CSP plant is constructed.Then,based on the energy flow direction of the OCC unit,the net output power equation and the electric-carbon characteristic equation of OCC unit are established,and the coordinated operation principle of OCC unit and CSP plant is analyzed.In addition,the operation potential of the power-to-gas(P2G)device is further explored,and the mathematical model of the P2G device is constructed by considering the reaction waste heat and oxygen recovery.On this basis,the reward and punishment ladder-type carbon trading mechanism is introduced to limit carbon emissions,and a low-carbon economic dispatch model of integrated electricity-heat-gas energy system is established.Finally,the effectiveness and economy of the proposed scheme are verified by the analysis of basic operation results,multi-scenario comparison verification and influence analysis of parameter changes.The following conclusions can be drawn from the simulation analysis:(1)The coordinated operation of OCC unit and CSP plant can meet the multi-energy demand of the system,realize the two-way conversion of multiple energy,and improve the flexibility and economy of the system.(2)The CSP pant with heat recovery device can realize the operation of'combined heat and power'and the circulation of heat energy,which improves the continuous operation ability and energy utilization efficiency of CSP plant.(3)After the low-carbon transformation of gas turbines by OCC technology,the output range and operation cleanliness can be effectively improved,and the combination of OCC units and power-to-gas equipment can realize carbon resource circulation.(4)The P2G device has a variety of energy supply potential,and the change of operating efficiency will affect the operational cost and oxygen energy consumption of the system.(5)The change of light intensity has obvious influence on the operation capacity of CSP power station and the operation plan of OCC unit.