Electric power generation technology of natural gas pressure reduction:Insights from black box-gray box hierarchical exergy analysis and evaluation method

Based on the“three box”exergy analysis model,a black box-gray box hierarchical exergy analysis and evaluation method is put forward in this paper,which is applied to evaluate the power generation technology of differential pressure produced by natural gas expansion.By using the exergy analysis theory,the black box-gray box hierarchical exergy analysis models of three differential pressure power generation technologies are established respectively.Firstly,the“black box”analysis models of main energy consuming equipment are established,and then the“gray box”analysis model of the total system is established.Based on the calculation results of exergy analysis indexes,the weak energy consumption equipment in the whole power generation process is accurately located.Taking a gas field in southwest China as an example,the comprehensive energy consumption evaluation of the three power generation technologies is carried out,and the technology with the best energy consumption condition among the three technologies is determined.Finally,the rationalization improvement measures are put forward from improving the air tightness,replacing the deflector and reducing the flow loss.

飞轮储能在钻机动力调峰中的应用研究

石油钻机起下钻工况中的载荷呈现脉冲波动特性,为了应对短时冲击负荷,有必要引入飞轮储能调峰运行技术,以平抑发动机的功率突增,减少动力热备容量,达到节能减排的目的。提出一种基于飞轮储能的混合动力传动系统,飞轮储能系统储存辅助发电机的小功率电能、下钻工况中的势能回收电能,大功率释放电能供给调峰电机。飞轮储能系统与绞车下钻势能回收系统、辅助发电系统、调峰电机系统组网联合调试,在卫453井示范工程中进行调峰试验、液力耦合器配置试验、能量回收功能试验、调峰电机系统电气总控试验。试验结果表明,飞轮储能动力调峰系统能够快速响应载荷的变化,将柴油机在响应冲击负荷时的功率突增减少40%~58%。柴油机与链条并车箱之间的液力耦合器可以用传动效率更高的齿轮变速器替代,无液力耦合器的混合动力系统油耗可降低10%以上。

两种新型调压室的设计及试验论证

调压室是保证水力发电运行稳定性及供电质量的常用解决方案。以差动式及阻抗式调压室为对比对象,设计了瓣膜隔离强冲击式及涌波发电掺气耗能式两种水能自耗式调压室,侧重优化了传统调压室的消能方式,一方面通过减小调压室水位波动振幅而降低其工程造价,另一方面通过加速调压室水位波动衰减而更好地保证水电站的供电质量。通过一系列的模型试验对两种调压室的技术可行性进行了论证。结果表明:瓣膜隔离强冲击式调压室在技术上可行,各方面性能较好,可像差动式调压室一样适用于中高水头的水电站;涌波发电掺气耗能式调压室在控制涌波高度及波动衰减时长上有一定的效果,可作为传统阻抗式调压室的技术改进方案。