Adsorption Materials and Processes for Carbon Capture from Gas-Fired Power Plants - AMPGas

《2008年气候变化法》设定了一个具有法律约束力的目标，即到2050年减少80%的二氧化碳排放。为了应对这一挑战，英国气候变化委员会(CCC)定期发布碳预算，就英国需要减少排放的方式提出建议。在其2010年第4次碳预算中，有一个明确的计划，即到2030年电力部门脱碳，投资30-40千兆瓦的低碳产能，价值约1000亿GB。到2030年，这将把发电的平均排放量降低到50gCO2/kWh左右，并在2020年前包括4个CCS示范工厂。CCC认识到英国燃气发电厂的关键作用：目前46%的发电量和35%的排放来自天然气。报告还指出，CCS改造对于现有的CCGT工厂来说是一个有吸引力的选择，表明目前系统中的20千兆瓦的工厂适合在2020年代进行改造，以及在未来十年(10-15千兆瓦)增加的任何工厂。到本世纪30年代，CCGT发电厂可能贡献25%的发电量。CCS成本的大约2/3存在于捕获过程中，而节省成本的最大机会就在这里。因此，政府正在支持研究，以开发更好和更低成本的工艺和设备，这项建议直接与这一目标保持一致，以支持英国经济，并帮助英国在未来10至20年内引领这一新兴技术。根据CCC的建议，这项建议的重点是捕获技术，用于改造现有的CCGT工厂。我们建议开发下一代增强型捕集技术，特别是通过新型先进吸附剂和使用旋转轮吸附器优化快速循环热再生来缩小工厂规模。研究挑战-燃气发电厂燃烧后捕集的关键挑战是烟道气中二氧化碳浓度较低，以体积计约为4%。这意味着传统的胺工艺将有很大的能量损失，而高浓度氧气的存在会导致高的胺失活率。新型的吸附剂和吸附过程有可能提高分离过程的效率。考虑到烟气中二氧化碳分压很低，新型吸附剂的选择与燃煤电厂的等值方法有很大不同。吸附剂必须具有非常高的选择性，才能在稀薄混合物中实现良好的捕集能力。因此，这些材料必须以非常强的物理吸附或化学吸附为基础，并且必须通过热循环进行再生。这就提出了开发一种能够实现几分钟量级的快速热波动的工艺的工程挑战，这比传统的热摆动吸附(TSA)固定床工艺快了一个数量级以上。我们计划制定一项雄心勃勃的工作计划，解决燃气发电厂碳捕获的材料和工艺开发问题。

The 2008 Climate Change Act sets a legally binding target of 80% CO2 emissions reductions by 2050. To meet this challenge the UK Climate Change Committee (CCC) issues regular carbon budgets with recommendations on the way in which the UK needs to reduce its emissions. In its 2010 4th carbon budget, there is a clear plan for power sector decarbonation to 2030, by investing in 30-40 GW of low carbon capacity with a value of the order of £100 billion. This would drive average emissions from generation down to around 50gCO2/kWh by 2030 and includes 4 CCS demonstration plants by 2020. The CCC recognises the key role for the UK of gas fired power plants: 46% of current electricity generation and 35% of emissions are from gas. It also identifies CCS retrofit as an attractive option for existing CCGT plants, indicating that 20GW of plant currently on the system would be suitable for retrofit in the 2020s, together with any plant added over the next decade (10-15 GW). CCGT plants are likely to contribute 25% of electricity generation in the 2030s. Roughly 2/3 of CCS costs lie in the capture process and it is here that the greatest opportunities for savings lie. Therefore, the Government is supporting research to develop improved and lower cost processes and equipment and this proposal is directly aligned with this aim in order to support the UK economy and help the UK take the lead in this emerging technology over the next 10 to 20 years.In line with the CCC recommendations the focus of this proposal is on capture technology for retrofit to existing CCGT plants. We propose to develop next generation enhanced capture technology and in particular reduce plant size through novel advanced adsorbents and the optimisation of fast cycle thermal regeneration using rotary wheel adsorbers.Research challenge - The key challenge in post combustion capture from gas fired power plants is due to the low CO2 concentration in the flue gas, approximately 4% by volume. This means that conventional amine processes will have a large energy penalty and the presence of high concentration of oxygen leads to high amine deactivation rates. Novel adsorbents and adsorption processes have the potential to improve the efficiency of the separation process. Given the very low CO2 partial pressure in the flue gas, the selection of novel adsorbents is very different from the equivalent approach to coal fired power plants. The adsorbents will have to have a very high selectivity to achieve good capture capacity with dilute mixtures. As a result these materials will have to be based either on very strong physisorption or chemisorption and the regeneration will have to be by thermal cycling. This poses the engineering challenge of developing a process that will achieve rapid thermal swings of the order of a few minutes, which is over an order of magnitude faster than traditional Thermal Swing Adsorption (TSA) fixed bed processes. We plan an ambitious programme of work that will address both materials and process development for carbon capture from gas fired power plants.