油田燃煤电厂CO_2捕集纯化工程实践

CO2是一种温室气体,通过CO2收集、驱油技术,能将造成温室效应的气体用于提高原油采收率,同时减少工业生产中温室气体的排放。为了实现CO2的捕集纯化,胜利油田采用一乙醇胺溶液(MEA)化学吸收工艺捕集CO2。介绍了"低渗透油藏CO2驱油"重大先导试验,在胜利发电厂建设CO2捕集纯化装置,通过此装置收集稳定、廉价的CO2气体用于驱油生产实践。通过分析系统运行状况,对装置进行了一系列的试验、研究,总结了大量CO2捕集系统的工程应用经验。胜利油田CO2捕集项目,通过将大型燃煤电厂烟道气中CO2捕集纯化、安全输送等系列技术攻关,形成低能耗捕集纯化、运输的集成配套技术。     

电厂CO2捕集工艺夹点分析与过程集成节能

电厂一乙醇胺（MEA）法烟气CO2捕集（CCS）工艺换热网络能量流密集,固有能耗高,对该工艺进行过程集成节能研究,具有重要意义。对CO2捕集工艺换热网络的夹点分析说明该换热网络存在跨越夹点的热量传递。冷热物流的总复合曲线特征说明了CO2捕集工艺固有能耗高的特性。对换热网络进行调优并提出了节能技术方案：（1）在夹点之上利用MEA贫液的部分高温位热量加热预吸附塔再生气;(2)采用MEA再生塔产生的湿CO2混合物作为驱动热源,跨越夹点设置一台氨吸收式制冷机以替代CO2液化所需部分制冷量。基于过程集成节能提出的换热集成节能措施可有效降低CO2捕集工艺固有能耗,使蒸汽耗量降低21%,冷却水耗量降低17.2%,CO2液化所需低温冷却公用工程降低43.4%。     

不同CO2捕集技术的CO2耦合绿氢制甲醇工艺研究

大量的化石燃料燃烧导致温室气体排放增加,全球气候变暖。世界各国以全球协约的方式减排CO₂,我国也由此提出“碳达峰·碳中和”目标。CO₂捕集以及转化制液体燃料和化学品是双碳目标下行之有效的碳减排措施之一,不仅可以实现CO₂的资源化利用,同时也缓解了国家能源安全问题。本文以燃煤电厂烟气CO₂捕集和CO₂合成甲醇为研究对象,分析了基于四种不同CO₂捕集技术的CO₂耦合绿氢制甲醇工艺。对四种不同CO₂捕集技术的CO₂制甲醇工艺进行了严格的稳态建模和模拟,分析和比较了不同CO₂捕集技术情景下的CO₂制甲醇工艺的技术和经济性能。结果表明,MEA、PCS、DMC和GMS情景的单位甲醇能耗分别是7.81、5.48、5.91和4.66 GJ/ t CH₃OH,GMS情景的单位能耗最低,其次是PCS情景,但随着更高效相变吸收剂的开发,PCS情景的单位甲醇产品的能耗将降低至2.29~2.58 GJ/t CH₃OH。四种情景的总生产成本分别是4314、4204、4279和4367 CNY/ t CH₃OH,PCS情景的成本最低,更具有经济优势。综合分析表明PCS情景的性能表现最好,为可用于燃煤电厂最佳的碳捕集技术,为CO₂高效合成燃料化学品提供方向,缓解化石燃料短缺和环境污染问题。     

不同CO2捕集技术的CO2耦合绿氢制甲醇工艺研究

大量的化石燃料燃烧导致温室气体排放增加,全球气候变暖。世界各国以全球协约的方式减排CO₂,我国也由此提出“碳达峰·碳中和”目标。CO₂捕集以及转化制液体燃料和化学品是双碳目标下行之有效的碳减排措施之一,不仅可以实现CO₂的资源化利用,同时也缓解了国家能源安全问题。本文以燃煤电厂烟气CO₂捕集和CO₂合成甲醇为研究对象,分析了基于四种不同CO₂捕集技术的CO₂耦合绿氢制甲醇工艺。对四种不同CO₂捕集技术的CO₂制甲醇工艺进行了严格的稳态建模和模拟,分析和比较了不同CO₂捕集技术情景下的CO₂制甲醇工艺的技术和经济性能。结果表明,MEA、PCS、DMC和GMS情景的单位甲醇能耗分别是7.81、5.48、5.91和4.66 GJ/ t CH₃OH,GMS情景的单位能耗最低,其次是PCS情景,但随着更高效相变吸收剂的开发,PCS情景的单位甲醇产品的能耗将降低至2.29~2.58 GJ/t CH₃OH。四种情景的总生产成本分别是4314、4204、4279和4367 CNY/ t CH₃OH,PCS情景的成本最低,更具有经济优势。综合分析表明PCS情景的性能表现最好,为可用于燃煤电厂最佳的碳捕集技术,为CO₂高效合成燃料化学品提供方向,缓解化石燃料短缺和环境污染问题。     

The multi-period optimisation of an amine-based CO2 capture process integrated with a super-critical coal-fired power station for flexible operation

In this work, we present a model of a super-critical coal-fired power plant integrated with an amine-based CO₂ capture process. We use this model to solve a multi-period dynamic optimisation problem aimed at decoupling the operation of the power plant from the efficiency penalty imposed by the CO₂ capture plant, thus providing the power plant sufficient flexibility to exploit price variation within an electricity market. We evaluate four distinct scenarios: load following, solvent storage, exhaust gas by-pass and time-varying solvent regeneration. The objective is to maximise the decarbonised power plant's short run marginal cost profitability. It is found that while the solvent storage option provides a marginal improvement of 4% in comparison to the load following scenario, the exhaust gas bypass scenario results in a profit reduction of 17% whereas the time-varying solvent regeneration option increases the profitability of the power plant by 16% in comparison to the reference scenario.     

Optimization of the various modes of flexible operation for post-combustion CO2 capture plant

One option to mitigate the adverse effect of power plant output loss from adding a CO₂ capture plant is to operate it in flexible modes in which the capture level and/or regeneration rate are dynamically varied in response to varying electricity market demand and price. This can help the plant meet peak electricity demand and improve its overall profit. However, the benefit is offset by higher capital costs and/or CO₂ emission penalty. Various modes of flexible operation including capture level reduction and solvent storage have been optimized for a given post-combustion capture system with typical daily electrical energy price patterns and the results are compared with those from a fixed point operation. Effects of varying storage capacities and energy price patterns have also been evaluated. Simultaneous use of the two flexible modes is also optimized and the result showed significantly higher cost savings compared to the individual uses.     

Optimal design for flexible operation of the post-combustion CO2 capture plant with uncertain economic factors

The ultimate benefit of flexible operation of the post-combustion CO₂ capture (PCC) plant depends on the ability to optimally balance between many competing factors, including the additional capital investment and operating cost savings. In this work, a large number of scenarios are constructed by considering combinations of possible realizations of the uncertain economic factors such as energy cost profile, emission penalty and value of captured CO₂. Then, the design choices like the size of the storage tanks and the regeneration capacity are optimized by minimizing an overall cost averaged over all the scenarios. The optimal design problem is naturally formulated as a two-stage stochastic program. This multi-scenario optimal design is compared with the design that minimizes the overall cost for just a single nominal scenario as well as the design that minimizes the cost averaged over the worst-case scenarios.     

尿素装置CO2压缩机组控制策略

详细介绍了尿素装置CO2压缩机组的控制策略。一套完善的控制方案能够有效地保护压缩机安全和节能降耗,同时减轻工艺操作人员工作强度。尤其是在多机组串、并联应用时,采用一套完善的、合理的、自控程度高的控制方案时,只要对整个控制目标(主变参数)进行设定,就完全可以达到预期要求。     

燃烧尾气后处理的反应溶剂型大型工业CO2吸收塔工艺技术进展

介绍了工业化经济型CO₂吸收塔的实体案例,总结近十年来工业化CO₂吸收塔的化工装置以及工程技术进展。系统介绍了CO₂吸收塔的化工工艺装置在运行中经常遇到的技术问题以及相应的解决方案,并分析近十年来几类技术发展,分别是溶液降解和降解产物处理技术、气体排放尾气的采样和分析技术、吸收剂主体组分分析技术、降低总体能耗的催化吸收-解吸技术。通过分析可知,利用固体矿物和生物催化剂是降低能耗的有效方法,但存在大量技术问题有待完善和解决。总之,这一系列的化工工艺技术的发展和进步,会为完善经济型吸收塔提供更多可信的实际数据。因此,燃烧尾气后处理的溶剂型CO₂吸收化工工艺装置必然朝着更小的反应器(吸收塔)和更低的能耗发展目标前进,从而实现该装置的高效率和低成本运行。     

耦合膜分离的新型CO2低温捕集系统性能优化

CO₂捕集作为温室气体排放控制的有效手段已成为重要研究课题。作为新兴捕集技术之一,低温CO₂捕集因产品纯度高、无附加污染等优势受到关注。然而,该技术能耗和捕集率对于气体中CO₂浓度十分敏感,对于高CO₂浓度气体可获得较高的CO₂捕集率和较低能耗水平。基于此,本文提出了耦合膜分离的新型CO₂低温捕集系统,通过膜材料选择渗透性实现待捕集气体CO₂浓度主动调控,并在最优浓度下进行CO₂低温捕集。首先基于不同传统低温捕集系统特点,对比分析了不同耦合系统模式,从而确定了最优耦合系统结构。针对最优耦合系统进行了运行参数优化,并分别基于实现系统捕集能耗最低与捕集率最高的目标,获得了膜渗透侧CO₂浓度与进气CO₂浓度间的关系式,为该耦合系统中膜组件选型提供指导。研究表明,本文提出的耦合系统捕集能耗为1.92MJ/kgCO₂,相比于传统单一低温系统捕集能耗可降低16.5%。     

负载型K2CO3/Al2O3二氧化碳吸收剂的碳酸化反应特性

引言 全球变暖已经成为一个备受关注的环境问题.据预测,如不采取积极的温室气体减排措施,从现在起到2100年,全球近地面平均气温将继续升高1.4～5.8℃[1].CO2是主要的温室气体,而我国燃煤电厂是CO2排放量最大、最集中的化石燃料燃烧场所.因此研究和开发适用于燃煤电厂的CO2减排技术至关重要.     

氨基修饰复合型钠基吸收剂的脱碳特性

为弥补常规钠基吸收剂活性差、脱碳量低的不足,制备了多种表面氨基修饰的新型复合型钠基吸收剂并研究其脱碳特性。通过比较氨基流失率和实际脱碳量,选定二氧化硅的前驱物正硅酸乙酯为载体前驱物,以碳酸钠为活性成分,分别以3-氨基丙基三甲氧基硅烷(APS)、3-氨基丙基三乙氧基硅烷(APTES)、二乙烯三胺(DETA)、三乙烯四胺(TETA)为氨基前驱物,制备得到多种表面氨基修饰的复合型钠基吸收剂。探究各种吸收剂的孔隙结构与脱碳特性,结果表明,APS、APTES修饰后吸收剂孔隙特性较差,脱碳量较低,DETA、TETA修饰后吸收剂孔隙结构得到改善,脱碳量较高。     

一种低能耗捕集CO2煤基甲醇和电力联产过程设计

传统的煤制甲醇过程所需合成气的氢碳比为2.1左右,而煤气化粗合成气氢碳比仅为0.7左右,因此需要将部分合成气进行变换来调节氢碳比。然而,变换气与未变换气混合后使得CO₂浓度降低,从而导致CO₂捕集能耗增加。提出了一种低能耗捕集CO₂煤基甲醇和电力联产过程。新联产过程中部分粗合成气首先经过变换,将CO转变为H₂和CO₂,CO₂浓度提高,在此时进行CO₂捕集可实现捕集能耗的降低。经CO₂捕集后,得到富H₂气体,富H₂气体分流后与另一部分煤气化粗合成气混合调节甲醇合成的氢碳比。对新的过程进行了建模、模拟与分析。结果表明相比传统的带CO₂捕集的煤制甲醇和IGCC发电过程,新的联产过程的能量节约率可达到16.5%,CO₂捕集能耗下降30.3%。     

低分压CO_2回收新技术捕集燃煤电厂烟气CO_2

基于分子模拟和设计,开发了以一乙醇胺(MEA)为主溶剂,优选添加了活性胺、抗氧化剂和缓蚀剂组成了适用于回收低分压CO2的优良复合吸收剂,在华能北京热电厂建立了我国第1套燃煤电站烟气CO2捕集示范装置,并完成了运行测试。结果表明:CO2回收装置出来的CO2纯度为99.5%(体积分数),每tCO2蒸汽消耗为3.5GJ,每tCO2溶液消耗小于1.5kg。该套装置的建成和各项指标试验的进行将为我国大规模推广电站CO2捕集奠定基础。     

Photochemical and acoustic interactions of biochar with CO2 and H2O: Applications in power generation and CO2 capture

A critical literature review suggests that carbonaceous compounds react with (CO₂ +H₂O) mixture through thermal, photochemical, and sonochemical/sonophysical routes. A biochar was selected for studying these effects at 60°C and 1 atm for its potential benefits on power generation and CO₂ capture. All treatments remove sizable minerals (K, Na, and Si) detrimental in power generation, and introduce carbon (up to 16% of original carbon in biochar) into the biochar matrix. Most treatments show increased hydrogen (up to 24%). Treatments lead to notable increased heating value of biochar (up to 50%). Treated biochars show increase (up to 19 fold) in internal surface area. The ultrasound energy output is a fraction of the increased heating value. Thus, pretreatment is potentially attractive for increasing the energy efficiency in combustion and gasification. Moreover, better understandings of the salient reactions of these processes will be advantageous for the development of advanced adsorbents for CO₂ capture. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1054–1065, 2014     

Exploring aramid as emerging contender for CO2 capture

To prevent CO_2 accumulation in the atmosphere generated from scorching of fossil fuels, carbon capture and sequestration(CCS) technology is considered as a potential route to mitigate the emissions of CO_2 from reaching the atmosphere. Power generation from sources such as gas, coal and biomass can fulfill the energy demand more readily than many other sources of electricity production. Thus these sources may be retained as important alternative option in the global energy cycle. In order to curtail CO_2, porous aramid network was fabricated by the condensation of 1,3,5-benzenetricarbonyl trichloride and 1,3-phenylenediamine in 1,4-dioxane solvent. Aramid was characterized for various analyses including FTIR, XRD, TGA, BET surface area and pore size analysis, FESEM and CO_2 adsorption measurements. Excellent thermal stability was provided by strong amide linkages in the polymer backbone. Optimum CO_2 uptake of aramid was achieved to be 23.14 mg·g~(-1) at 273 K at 0.1 MPa. The basic amide groups of network structure showed greater affinity for CO_2.Excellent thermal stability of aramid makes it a promising sorbent for CO_2 capture in adverse conditions.     

设置循环洗涤流程稳定二氧化碳压缩工况

针对生产运行过程中脱氢反应器压差无法得到有效稳定控制及CO2压缩功耗上升问题进行原因探讨,提出相应的解决方案并实施技术改造,取得了较为良好的效果.     

Integration of a Ca looping system for CO2 capture in existing power plants

This work analyses a Ca looping system that uses CaO as regenerable sorbent to capture CO₂ from the flue gases generated in power plants. The CO₂ is captured by CaO in a CFB carbonator while coal oxycombustion provides the energy required to regenerate the sorbent. Part of the energy introduced into the calciner can be transferred to a new supercritical steam cycle to generate additional power. Several case studies have been integrated with this steam cycle. Efficiency penalties, mainly associated with the energy consumption of the ASU, CO₂ compressor and auxiliaries, can be as low as 7.5% p. of net efficiency when working with low‐CaCO₃ make‐up flows and integrating the Ca looping with a cement plant that makes use of the spent sorbent. The penalties increase to 8.3% p. when this possibility is not available. Operation conditions aiming at minimum calciner size result in slightly higher‐efficiency penalties. © 2010 American Institute of Chemical Engineers AIChE J, 2011     

燃煤电厂CO2捕集中烟气预处理系统的优化模拟

在燃煤电厂CO₂捕集中,为了提高其捕集效率,需对进入系统的烟气进行预处理。为进一步提高进入系统烟气的质量,本文用Aspen Plus模拟优化烟气预处理系统,通过研究在预洗塔中组合填料、填料层高度、吸收剂进量和分层进吸收剂对出口烟气中SO₂的含量、脱硫效率以及出口烟气温度的影响,得出最佳的工艺条件。模拟结果表明,加入不同种类组合填料,同种类不同型号组合填料和分层进吸收剂都使烟气脱硫效率增加,出口烟气温度降低;随着填料层高度和吸收剂进量的增加,出口烟气中SO₂的含量和出口烟气温度降低,其中最佳的高度为2~4m,最佳的吸收剂进量为(250~350)×10³kg/h。     

Pyrene-based hypercrosslinked microporous resins for effective CO2 capture

Two hydrophobic pyrene-based hypercrosslinked microporous resins (ZLYs) with intrinsic hydroxyl groups on the pore-walls have been prepared by condensation of 1,3,6,8-tetrakis(p-formylphenyl)pyrene (TFPPy) with phloroglucinol (L₁) or 1,5-dihydroxynaphthalene (L₂). The resulting porous networks exhibited high thermal stabilities and moderate Brunauer–Emmett–Teller surface area with 647 and 243 m² g⁻¹ respectively. The experiments showed that the weak interactions between CO₂ and the intrinsic hydroxyl groups on the pore-wall of the resins could enhance CO₂ uptake and CO₂/CH₄ selectivity. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47448.