Post-combustion emissions control in aero-gas turbine engines,Energy & Environmental Science

当前位置： X-MOL 学术 › Energy Environ. Sci. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Post-combustion emissions control in aero-gas turbine engines
Energy & Environmental Science ( IF 32.4 ) Pub Date : 2020-12-7 , DOI: 10.1039/d0ee02362k
Prakash Prashanth _{1,

2,

3,

4,

5} , Raymond L. Speth _{1,

2,

3,

4,

5} , Sebastian D. Eastham _{1,

2,

3,

4,

5} , Jayant S. Sabnis _{1,

2,

3,

4,

5} , Steven R. H. Barrett _{1,

2,

3,

4,

5}

Affiliation

Emissions of nitrogen oxides (NO_x) from aircraft cause air quality degradation and climate change. Efforts to improve the efficiency of aircraft propulsion systems are leading to small, power-dense engine cores with higher overall pressure ratios and combustion temperatures, which can result in higher NO_x emissions. The trend towards smaller engine cores with smaller mass flow rates in the core stream, presents new opportunities for emissions control. Specifically, we propose and assess using a selective catalytic reduction (SCR) system that was previously infeasible when mass flow rates in the core were an order of magnitude larger than heavy-duty diesel engines for road based applications. SCR systems would reduce NO_x emissions at the cost of increased aircraft weight and specific fuel consumption due to the pressure drop in the core stream induced by the catalyst. We quantify the effects of these trade-offs in terms of emissions reduction and fuel burn increase using representative engine cycle models provided by a major aero-gas turbine manufacturer. Due to its size, any SCR system will likely need to be housed in the aircraft body, potentially making it most suitable for future hybrid- or turbo-electric aircraft designs. Furthermore, SCR systems require ultra-low sulfur (ULS) fuel to prevent catalytic fouling. We find that employing an ammonia-based SCR results in an approximately 95% reduction in NO_x emissions in exchange for a ∼0.5% increase in block fuel burn. The performance of the post-combustion emissions control (PCEC) system is shown to improve for smaller-core engines, such as those proposed in the NASA N + 3 time-line (2030–2035). Using a global chemistry-transport model we estimate that PCEC used with ULS fuel, could avert ∼92% of aviation air pollution related early deaths each year. Using a simplified climate model and accounting for changes in emissions (including life cycle emissions) and radiative forcing we estimate that PCEC with ULS fuel increases climate damages by ∼7.5%. We estimate that the net benefit of using PCEC accounting for air quality and climate impacts is 304 USD (2015) per metric tonne of jet fuel burned, or a reduction of ∼52% in monetized air quality and climate damages.

中文翻译：

航空燃气涡轮发动机的燃烧后排放控制

飞机排放的氮氧化物（NO _x）会导致空气质量下降和气候变化。努力改善飞行器推进系统的效率是导致小，功率密度高的发动机核心与更高的总压力比和燃烧温度，这可导致较高的NO _X排放。发动机核心尺寸越来越小，核心流中的质量流量减小的趋势为排放控制提供了新的机遇。具体来说，我们提出并使用选择性催化还原（SCR）系统进行评估，该系统以前无法实现，而核心系统中的质量流量要比重型柴油机大一个数量级（用于公路应用）。SCR系统将减少NO _X由于催化剂引起的核心流中的压降，排放量增加了飞机的重量和特定的燃料消耗。我们使用主要的航空燃气轮机制造商提供的代表性发动机循环模型，在减少排放和增加燃料燃烧方面权衡这些权衡的影响。由于其尺寸，任何SCR系统都可能需要安装在飞机机体内，这可能使其最适合未来的混合动力或涡轮电动飞机设计。此外，SCR系统需要超低硫（ULS）燃料以防止催化污垢。我们发现，在使用中NO的约95％减少氨为基础的SCR结果_X排放量以换来的是大块燃油燃烧量增加约0.5％。燃烧后排放控制（PCEC）系统的性能已被证明对于较小核心的发动机有所改善，例如在NASA N + 3时间线（2030-2035年）中提出的那些。使用全球化学运输模型，我们估计与ULS燃料一起使用的PCEC每年可避免约92％的与航空空气污染有关的早期死亡。使用简化的气候模型并考虑排放量（包括生命周期排放量）的变化和辐射强迫，我们估计使用ULS燃料的PCEC可使气候损失增加约7.5％。我们估计，使用PCEC计算空气质量和气候影响的净收益为每公吨喷气燃料燃烧304美元（2015年），或将货币化的空气质量和气候损害减少约52％。

更新日期：2021-01-14

点击分享查看原文

点击收藏

公开下载

阅读更多本刊最新论文本刊介绍/投稿指南11