中温烟气余热动力回收CO_2超临界回热循环优化

考虑烟气的放热特性、一般冷源条件、中高温工况对工质热稳定性的要求和工质的环境特性,提出以CO2超临界循环(CO2-SC)作为初温300—500℃的烟气余热动力回收基础循环;针对CO2-SC吸热过程工质初温低、有限循环压比下膨胀过程终温过高的问题,对CO2-SC引入回热过程得到了CO2回热超临界循环(CO2-RSC)。对CO2-SC和CO2-RSC开展了以单位质量烟气的循环净输出功(比净功)最大为目标函数,以膨胀过程初温、初压、终压和回热度(对CO2-RSC)为优化变量的优化对比研究,结果表明:回热过程的引入,有效改进了循环效率,使循环比净功明显提高;在指定的换热器传热窄点温差和系统部件效率值下,烟气初温分别为300,400,500℃时,CO2-RSC的比净功较CO2-SC高50.9%,52.7%,49.6%。回热还使得CO2-RSC工质吸热过程初温高于烟气的酸露点,避免了超临界加热器烟气侧低温腐蚀问题。

基于合理参数控制下的唐钢4#烧结机生产实践

利用数据分析方法,对唐钢北区4#(180 m^2)烧结机的生产数据进行了统计、分析和研究。结合烧结机生产现状得出:在稳定匀矿吃入量68~73 kg/s,主排入口压力维持在16.6~17.3 kPa区间,烧结机机尾负压维持在14.7~15.5 kPa,机尾终点温度控制在380~410℃之间时,烧结矿转鼓强度为78.7%,烧结机大烟道温度125~135℃,余热烟温365~400℃,烧结机各项生产指标均处于最优范围区间内。

中温烟气为热源的CO_2跨临界循环改进及分析

着眼于初温为300-600℃的中温烟气余热动力回收,以单位质量烟气的循环净输出功（循环比净功）最大为优化目标,对CO2跨临界循环（CO2-TC）以及分别引入全回热、分流回热（部分冷却）措施形成的改进型循环,进行了性能优化对比分析。结果表明,全回热CO2-TC的比净功和循环热效率明显高于CO2-TC;在烟气初温较高的情形下,分流回热CO2-TC有最高的循环热效率,但比净功输出较低。

Optimal Analysis of Pure Low-Temperature Waste Heat Recovery Generation System

In this paper, a detailed thermodynamic analysis of the pure low-temperature waste heat recovery generation system is presented. The parameters affecting the system performance are compared to obtain the most significant ones; furthermore, parameter values are optimized for the largest power generating capability of the system. It is found that the most important parameters are inlet flue gas temperature, steam pressure and the pinch point temperature difference. There is an optimal superheated steam pressure value for giving the maximum generation power per unit flue gas. With the increase of inlet flue gas temperature, the generating power increases and the optimized steam pressure rises as well. However, with increase in pinch point temperature difference, the generating power decreases and the optimized steam pressure decreases as well. The theoretical calculation provides a theoretical basis for the parameters optimization in the design of the pure low-temperature waste heat recovery eeneration swtem