变压吸附(PSA)分离技术在炼化厂尾气回收中的应用

重点介绍了针对中国石化海南炼油化工有限公司(以下简称海南炼化)工业尾气排放,依托于变压吸附(PSA)分离技术所设计的一种有效回收炼化厂尾气的新工艺。采用该工艺能获得高纯度的H2,并可将其返回炼化厂重复利用,同时能够利用工业尾气制成食品级CO2。应用该工艺能够获得良好的经济社会效益,值得进一步推广应用。     

制氢装置副产二氧化碳资源化利用

CO2大量排放引发的温室效应越来越受到人们的重视,本文通过对CO2各种回收方法的对比,结合洛阳石化制氢工艺,提出了对制氢装置副产的CO2进行回收利用的可行性。     

天然气净化厂尾气中CO_2回收利用的可行性分析

CO2是一种碳资源,有多种用途,目前天然气净化厂尾气中的CO2均排放到空气中,不但浪费了资源,而且对环境起着不利的影响。本文分析了该气体回收是可行的,并提出了两种回收思路,将尾气CO2回收利用,具有一定的社会效益和经济效益。     

新华粤煤制氢CO_2废气综合利用装置建成投产

正广东新华粤集团10万吨/年煤制氢CO2废气综合利用装置近日一次开车成功,标志着华南地区最大的食品级CO2生产装置在茂名正式建成投产。广东新华粤集团是隶属于茂名石化公司的改制企业,这套装置以茂名石化20万立方米/小时煤制氢装置排放的含CO2尾气作原料,采用国内先进的     

广东新华粤建成10万吨/年煤制氢CO_2废气综合利用装置

<正>广东新华粤集团10万吨/年煤制氢CO2废气综合利用装置近日一次开车成功,标志着华南地区最大的食品级CO2生产装置在茂名正式建成投产。广东新华粤集团是隶属于茂名石化公司的改制企业,这套装置以茂名石化20万立方米/小时煤制氢装置排放的含CO2尾气作原料,采用国内先进的催     

SCOT法尾气处理工艺关键参数控制及优化

普光天然气净化厂硫磺回收装置单套回收能力达到20万t每年,采用两级克劳斯工艺加SCOT尾气处理工艺。本文主要讨论SCOT法尾气处理工艺关键参数控制及优化,为大型硫磺回收装置的尾气处理单元提供参考依据。     

基于PSA法在炼油厂装置尾气中回收应用研究

在炼油厂的炼油与石化装置的生产过程中,容易产生很多富氢尾气。对尾气中氢气的回收,是全球石油化工相关科技人员的研究执点。当前对炼油厂与石化装置尾气中氢气的回收,主要采用PSA(变压吸附)法、膜分离法与深冷分离等方法,其中以PAS法更具优势与特点。以中国石化海南炼油化工有限公司(海南炼化厂)工业尾气综合利用技术研究项目为例,首先对变压吸附技术应用回收氢气的可行性进行分析;然后对回收流程与装置标定进行详细论述。最后得出结论:使用变压吸附技术能够提升氢气的利用率,回收率达到94.7%,且没有污染,同时PSA装置运行较好,产品能够满足对下游装置氢气的需求。     

油气回收装置优化运行方案

北方华锦化学工业集团炼化分公司建有装车尾气回收装置两套,这两套装置均采用冷凝+吸附工艺方案,于2018年8月开始试运行,其尾气经检测符合《石油炼制工业污染物排放标准》(GB31570-2015)中的排放要求。根据本油气回收装置试生产期间出现的各种问题,结合相关分析指标,归纳出油气回收系统排放指标波动的原因,并提出了解决方案。     

膜回收及吸收组合工艺回收干气中液化气组分

以某厂的实际应用为例,介绍了一种从干气制燃料油的尾气中回收低浓度液化气组分的工艺方法。该方法应用了膜回收结合汽油吸收、柴油吸收的组合工艺,实现了低能耗、高效地回收尾气中的液化气组分。在保证液化气组分回收率的前提下,以下游装置可接收性及整体经济效益为指标,通过Aspenplus工艺流程模拟软件优化了汽油吸收及柴油吸收的工艺操作条件。装置稳定运行后标定数据表明,该工艺实现该尾气中C_3及以上轻烃组分回收率达到94%以上,年回收液化气组分约2 500 t,具有良好的经济效益及社会效益。     

制氢尾气生产食品级二氧化碳技术探讨

分析了中国石油化工股份有限公司荆门分公司制氢装置的制氢尾气情况,探讨了利用制氢尾气生产食品级二氧化碳的技术方案。根据该装置制氢尾气组成,确定采用精脱硫、催化氧化与精馏组合工艺,产品质量完全可以达到IBST和GB10621-2006标准,减少了二氧化碳排放,具有较好的经济效益和环保效益。     

膜分离回收系统在渣油加氢装置的应用

四川石化有限责任公司300×104 t/a渣油加氢脱硫装置采用CLG公司的固定床渣油加氢脱硫工艺技术,高压分离器顶出的循环氢排放量约13000 Nm3/h,尾气氢含量在80%以上。利用气体膜分离技术回收氢气,并将回收氢气作为装置的补充氢源,这不仅提高了氢源的利用率,降低制氢装置的生产负荷,缓解供氢矛盾,而且也降低了渣油加氢装置的成本。     

Combination of Sorption-Enhanced Steam Methane Reforming and Electricity Generation by MCFC: Concept and Numerical Simulation Analysis

Abstract

Reformed gas made by the steam methane reforming(SMR) process is used as fuel feed to MCFC, but it is not as good as pure hydrogen due to the presence of CO₂ and CO. The sorption-enhanced steam methane reforming(SE-SMR) process can reduce CO₂ and CO to a low level and produce high purity hydrogen. Considering the merits of similar operating temperatures (about 500°C) and carbon dioxide recycle, a novel concept of a six-step sorption-enhanced steam methane reforming (SE-SMR) combined with electricity generation by molten carbonate fuel cell (MCFC) is proposed. In the present paper, a cycle of the SE-SMR process, which include the steps of reaction/adsorption, depressurization, gas purges (nitrogen and reformed gas, respectively), and pressurization with reformed gas, is modeled and analyzed. The process stream in the SE-SMR process is used as anode feed in MCFC. According to the result of numerical simulation, a fuel cell grade hydrogen product (above 80% purity) at the SE-SMR temperature of 450°C can be obtained. A carbon dioxide recycle mechanism is developed for cathode feed of MCFC from flue gas by burning with excess air to achieve a proper CO₂/air ratio (about 30:70). The novel electricity generation system, which can operate at lower energy consumption and high purity hydrogen feed is helpful for the MCFC'S performance and life time.     

CO 2脱氢技术在尿素斯那姆氨汽提工艺中的应用

针对锦天化尿素装置中压放空尾气长期处于爆炸极限范围内这一安全隐患,实施了在尿素合成塔前增加CO2脱氢装置的技改措施。技改结果表明：脱氢装置使用富氧与未增加脱氢装置对比取得总经济效益81．29万元,并消除了中压放空尾气爆炸的隐患。     

Hydrogen production from biomass: The behavior of impurities over a CO shift unit and a biodiesel scrubber used as a gas treatment stage

Most of the hydrogen produced is derived from fossil fuels. Bioenergy2020+ and TU Wien have been working on hydrogen production from biomass since 2009. A pilot plant for hydrogen production from lignocellulosic feedstock was installed onsite using a fluidized bed biomass gasifier in Güssing, Austria. In this work, the behavior of impurities over the gas conditioning stage was investigated. Stable CO conversion and hydration of sulfur components could be observed. Ammonia, benzene, toluene, xylene (BTX) and sulfur reduction could be measured after the biodiesel scrubber. The results show the possibility of using a commercial Fe/Cr-based CO shift catalyst in impurity-rich gas applications. In addition to hydrogen production, the gas treatment setup seems to also be a promising method for adjusting the H₂ to CO ratio for synthesis gas applications.     

水溶液全循环尿素工艺尾气安全操作分析

水溶液全循环尿素工艺无CO2脱氢装置，系统尾气中氢气含量较高，与防腐氧气混合后极易形成爆炸性气体，危及装置本质安全。通过对兖矿鲁南化肥厂水溶液全循环尿素装置惰性气体洗涤器（惰洗器）尾气各组分的可爆范围分析计算，提出实际的安全操作措施。     

煤、气、油联合生产甲醇实现资源互补和节能减排

介绍了以煤、油田气和渣油为原料联合生产甲醇的工艺流程及其特点。水煤浆气化有效气的n（H2）/n（CO）为0．4-0．5,天然一段蒸汽气转化有效气的n（H2）／n（CO）为2．7～3．0,根据H、C元素互补理论．联合生产甲醇工艺将水煤浆气化副产多余的CO、天然气转化过剩的H2和渣油催化裂解时副产的干气（分离回收的部分H2）3者结合使合成气中的生产甲醇的合成气【n（H2）-n（CO2）]／[n（CO）＋n（CO2）]达到2．05-2．15,达到“氢碳互补”,从而实现节能减排目的。     

Mechanisms leading to process improvements in lignite liquefaction using CO and H2S

Optimum distillate yields from US lignites can be as high on a dry, ash-free basis as those obtained from bituminous coals, but only if the vacuum bottoms are recycled. Lignites are more readily liquefied if the reducing gas contains some carbon monoxide and water, which together with bottoms recycle has proven to yield the highest conversions and the best bench-unit operability. The recycle solvent in the reported tests consisted of unseparated product slurry, including coal mineral constituents. Variability in coal minerals among nine widely representative US low-rank coals did not appear to correlate with liquefaction behaviour. Addition of iron pyrite did, however, improve yields and product quality, as measured by hydrogen-to-carbon ratio. Future improvements in liquefaction processes for lignite must maintain high liquid yields at reduced levels of temperature, pressure, and reaction time whilst using less reductant, preferably in the form of synthesis gas (CO + H₂) and water instead of the more expensive pure hydrogen. Understanding the process chemistry of carbon monoxide and sulphur (including H₂S) during lignite liquefaction is a key factor in accomplishing these improvements. This Paper reviews proposed mechanisms for such reactions from the viewpoint of their relative importance in affecting process improvements. The alkali formate mechanism first proposed to explain the reduction by CO does not adequately explain its role in lignite liquefaction. Other possible mechanisms include an isoformate intermediate, a formic acid intermediate, a carbon monoxide radical anion, direct reaction with lignite, and the activation of CO by alkali and alkaline earth cations and by hydrogen sulphide. Hydrogen sulphide reacts with model compounds which represent key bond types in low-rank coal in the following ways: (1) hydrocracking; (2) hydrogen donor; (3) insertion reactions in aromatic rings; (4) hydrogen abstraction, with elemental sulphur as a reaction intermediate; and (5) catalysis of the water-gas shift reaction. It appears that all of these reaction pathways may be operative when catalytic amounts of H₂S are added during liquefaction of lignite. In bench recycle tests, the addition of H₂S as a homogeneous catalyst reduced reductant consumption as much as three-fold whilst maintaining high yield levels when the reaction temperature was reduced by 60°C. Attainment of the high distillate yield at 400°C was accompanied by a marked decrease in the production of hydrocarbon gases, which normally is a major cause of unproductive hydrogen consumption and solvent degradation via hydrocracking. Processing with synthesis gas and inherent coal moisture using bottoms recycle and H₂S as a catalyst appears to be the most promising alternative combination of conditions for producing liquids from lignite at reduced cost.     

Combustion characteristics of lignite-fired oxy-fuel flames

This experimental work describes the combustion characteristics of lignite-fired oxy-fuel flames, in terms of temperature distribution, gas composition (O₂, CO₂, CO, total hydrocarbon concentration and NO) and ignition behaviour. The aim is to evaluate the flame structure of three oxy-fuel cases (obtained by changing the flue gas recycle rate) including a comparison with an air-fired reference case. Measurements were performed in Chalmers 100 kW test unit, which facilitates oxy-fuel combustion under flue gas recycling conditions. Temperature, O₂ and CO concentration profiles and images of the flames indicate that earlier ignition and more intense combustion with higher peak temperatures follow from reduction of the recycle rate during oxy-fuel operation. This is mostly due to higher O₂ concentration in the feed gas, reduced cooling from the recycled flue gas, and change in flow patterns between the cases. The air case and the oxy-fuel case with the highest recycle rate were most sensitive to changes in overall stoichiometry. Despite significant differences in local CO concentration between the cases, the stack concentrations of CO are comparable. Hence, limiting CO emissions from oxy-fuel combustion is not more challenging than during air-firing. The NO emission, as shown previously, was significantly reduced by flue gas recycling.     

气煤联产甲醇天然气转化工艺方案选择

介绍了气煤联产甲醇氢碳互补和天然气转化工艺原理,分析了不同转化工艺的过剩氢,对一段与二段转化的天然气消耗、煤气变换率、CO2排放、动力消耗、投资进行了比较,指出了一段蒸汽转化能起到很好的补氢作用,可使水煤气的变换率为最低,一段蒸汽转化无论是在天然气消耗、动力消耗、CO2排放,还是投资上均优于二段转化,是气煤联产甲醇的最佳转化方案。     

碳中和背景下工业副产气制氢技术研究与应用

我国工业副产气排放量大,在对环境造成污染的同时,副产气中H₂、CO等有效成分随排放而浪费。氢气既是重要的化工原料,也是无碳、高效的能源,用工业副产气制备或分离提纯氢气既减少资源浪费,又可减少CO₂排放。本文介绍了我国含氢工业副产气排放情况,详述了焦炉煤气制氢、炼厂副产气制氢、氯碱尾气制氢等三种典型工业副产气制氢工艺,对煤制氢、天然气制氢、甲醇制氢及三种典型工业副产气制氢工艺的成本和CO₂排放进行了计算和整理分析。文章指出,考虑二氧化碳排放和碳交易成本等因素,与煤制氢、天然气制氢、甲醇制氢和电解水制氢相比,现阶段下工业副产气制氢的综合成本优势更加明显。在碳中和背景下,工业副产气制氢是获取低碳氢气的有效和经济的途径,研究和开发工业副产气制氢技术,将为碳减排提供一条高效路径。