煤油气综合利用180万t/a甲醇联合装置合成催化剂使用寿命的延长实践

简述了靖边能源煤油气综合利用项目180万t/a甲醇装置的工艺流程,介绍了甲醇合成催化剂在装填、还原时的控制要点及生产运行期间的注意事项,并就预合成塔压降高导致的催化剂粉化、合成塔压降高导致的局部超温等问题进行了分析和处理,确保了甲醇合成催化剂使用寿命的延长。     

戴维甲醇合成塔超温原因分析与处理措施

介绍戴维（Davy）甲醇合成工艺及甲醇合成塔（SRC）结构特点，结合甲醇装置从原始开车至今的合成塔运行工况，得出合成塔结构、催化剂装填、空速、新鲜气分配失衡等是导致合成催化剂床层局部超温的主要原因，局部超温将使甲醇副反应增多，影响产量和催化剂活性。在通过对催化剂装填高度、氢碳比、空速、两个合成塔分配气量等调整后，缩小了超温范围，降低了超温点温度，保证了催化剂使用寿命，提高了催化剂整体使用效率。     

预合成塔未装催化剂情况下的合成系统稳定运行总结

在甲醇合成装置中,预合成塔分布器设计不合理造成运行阻力过大,进出口压差高达0.4MPa,预合成塔催化剂活性严重降低,合成气在预合成塔内参加反应的数量降低,合成反应主要集中在合成塔内。因预合成塔床层阻力问题,造成合成回路循环量降低,使合成气在主合成塔内反应的时间延长,造成合成塔温度超温,严重影响催化剂寿命。为降低合成塔运行时床层温度,消除预合成塔催化剂床层阻力,卸出预合成塔内旧催化剂,只保留合成塔催化剂。并调节合成系统各工艺参数,有效避免合成塔超温。     

甲醇合成塔床层超温原因分析

介绍了DAVY公司设计的大型甲醇合成流程,探讨了甲醇合成塔的内件结构,从催化剂的装填、催化剂还原后的沉降、工艺操作等方面对现运行的甲醇合成塔催化剂上部床层局部热点超温现象进行了分析。     

C307型催化剂在60万吨甲醇装置的工业应用

介绍了中石化南京化工研究院有限公司的C307型甲醇合成催化剂在神华宁煤甲醇分公司60万t·a~(-1)甲醇合成装置上的使用情况。详细介绍了催化剂的升温、还原、初期运行和正常生产等过程,应用结果表明,C307型甲醇合成催化剂具有活性好、单耗低、运行稳定等特点和优点。C307型甲醇合成催化剂与上炉催化剂在系统惰性气体含量、合成塔压差和CO单程转化率等使用性能及使用情况进行了对比,剖析、解决了使用过程中出现的合成塔初期活性低、压差大等问题,以期为不同装置选用催化剂提供参考。     

年产50万吨煤制甲醇装置工艺优化与技术改进

介绍大型甲醇合成装置工艺流程及特点,分析甲醇合成回路运行中存在的问题。通过并联1台新甲醇合成塔、改进升温回路等措施,大幅提高生产能力,并成功实现国产高性价比甲醇合成催化剂的应用。     

甲醇合成技术进展

综述了甲醇合成工艺的发展，分类介绍了一些先进的合成塔，如：激冷式合成塔、托普索CMD合成塔、鲁奇管式合成塔、林德等温合成塔等。对合成催化剂也作了相应介绍。     

甲醇合成催化剂失活问题分析与处理

介绍了Shell粉煤气化制甲醇工艺中甲醇合成系统流程及生产运行情况。对合成塔催化剂运行情况进行了总结;就催化剂失活、更换频率过快问题进行了分析;并对合成回路系统进行了一系列改造:在现有合成塔上并联1台新的合成塔,分担现有合成塔一部分负荷,以降低现有合成塔催化剂生产强度,降低床层热负荷,增强催化剂抗中毒能力,延长催化剂寿命。结果表明:改造后,降低了经济运行成本,每年直接节省334万元,且确保了装置的长周期、高负荷稳定运行。     

Davy大甲醇技术初期运行中床层超温问题的浅析

在国内外大甲醇技术日益发展的背景下,为了进一步推动大甲醇技术的推广和应用,本文主要就目前Davy的180万t甲醇合成工艺运行中,出现的合成塔超温问题进行初步的探讨,并对所出现的超温问题进行分析,同时说明由此造成的后果,再针对这一问题,结合装置的实际运行操作,提出了六点调整建议,并给出了调整后的结果。     

煤化工甲醇合成装置稳定运行分析与研究

如何实现煤化工甲醇合成装置的稳定运行,本文从甲醇合成工艺概述入手,以丹麦托普索公司的甲醇合成(BWR合成塔)工艺流程为例,重点从触媒的保护、进料比例的控制、合成塔塔温的控制三个方面深入展开对合成装置稳定运行进行了分析和研究,得出了甲醇合成装置要稳定运行,最主要的是要保护好触媒,提高触媒活性,同时还要依据触媒的使用情况,控制好进料比例、操作压力、操作温度和触媒床层温度等因素的结论。     

Methanol Synthesis

Methanol is a basic industrial chemical that is produced in the United States at an annual rate of over one billion gallons [1]. It is used as a solvent in many industrial processes, as a starting material for the production of other compounds, notably formaldehyde, and as a freezing point suppressing agent for gasoline lines and window washing liquids, as well as for many other purposes. Traditionally, methanol has been produced by catalytic hydrogenation of carbon monoxide.     

Methanol Synthesis

Abstract

Methanol is a basic industrial chemical that is produced in the United States at an annual rate of over one billion gallons [1]. It is used as a solvent in many industrial processes, as a starting material for the production of other compounds, notably formaldehyde, and as a freezing point suppressing agent for gasoline lines and window washing liquids, as well as for many other purposes. Traditionally, methanol has been produced by catalytic hydrogenation of carbon monoxide.     

Methanol Synthesis

Methanol, like ammonia, is one of the key industrial chemicals produced by heterogeneous catalysis. As with the original ammonia catalyst (Fe/K/Al₂O₃), so with methanol, the original methanol synthesis catalyst, ZnO, was discovered by Alwin Mittasch. This was translated into an industrial process in which methanol was produced from CO/H₂ at 400?°C and 200 atm. Again, as with the ammonia catalyst where the final catalyst which is currently used was achieved only after exhaustive screening of putative “promoters”, so with methanol, exhaustive screening of additives was undertaken to promote the activity of the ZnO. Early successful promoters were Al₂O₃ and Cr₂O₃ which enhanced the stability of the ZnO but not its activity. The addition of CuO was found to increase the activity of the ZnO but the catalyst so produced was short lived. Current methanol synthesis catalysts are fundamentally Cu/ZnO/Al₂O₃, having high CuO contents of?~60?% with ZnO?~?30?% and Al₂O₃?~?10?%. Far from promoting the activity of the ZnO by incorporation of CuO, the active component of these Cu/ZnO/Al₂O₃ catalysts is Cu metal with the ZnO simply being involved as the preferred support. Other supports for the Cu metal, e.g. Al₂O₃, MgO, MnO, Cr₂O₃, ZrO₂ and even SiO₂ can also be used. In all of these catalysts the activity scales with the Cu metal area. The original feed has now changed from CO/H₂ to CO/CO₂/H₂ (10:10:80), radiolabelling studies having provided the unlikely discovery that it is the CO₂ molecule which is hydrogenated to methanol; the CO molecule acts as a reducing agent. The CO₂ is transformed to methanol on the Cu through the intermediacy of an adsorbed formate species. These Cu/ZnO/Al₂O₃ catalysts now operate at?~230° and between 50 and 100 atm. This important step change in the activity of methanol synthesis has resulted in a significant reduction in the energy required to produce methanol. The “step change” however has been incremental. It has been obtained on the basis of fundamental knowledge provided by a combination of surface science techniques, e.g. LEED, scanning tunnelling microscope, TPD, temperature programmed reaction spectroscopy, combined with catalytic mechanistic studies, including radiolabelling studies and chemisorption studies including reactive chemisorption studies, e.g. N₂O reactive frontal chromatography.     

Deactivation of Copper Metal Catalysts for Methanol Decomposition, Methanol Steam Reforming and Methanol Synthesis

Laboratory and industrial results are reviewed to elucidate the general features of the deactivation of supported copper metal catalysts in various reactions involving methanol as reactant or product. Most catalyst types are based on Cu/ZnO formulations that contain stabilisers and promoters such as alumina, alkaline earth oxides and other oxides. These additional materials have several roles, including the inhibition of sintering and absorption of catalyst poisons. All copper catalysts are susceptible to thermal sintering via a surface migration process, and this is markedly accelerated by the presence of even traces of chloride. Care must be taken, therefore, to eliminate halides from copper catalysts during manufacture, and from reactants during use. Operating temperatures must be restricted, usually to below 300°C.In methanol synthesis involving modern promoted Cu/ZnO/Al₂ O₃ catalysts neither poisoning nor coking is normally a significant source of deactivation; thermal sintering is the main cause of deactivation. In contrast, catalyst poisoning and coking have been observed in methanol decomposition and methanol steam reforming reactions.     

低温甲醇洗装置甲醇污染物分析

1999年大检修结束后开车过程中发现低温甲醇洗工段工况严重恶化,几台缠绕式换热器相继出现换热能力下降、阻力增大的现象,尤其是1#、2#贫甲醇冷却器情况更为严重.系统中的甲醇遭到严重污染,装置中导淋排出的甲醇颜色发黑.整个低温甲醇洗工段表现出冷量严重不足、循环量不平衡、仅能维持50%系统负荷,生产无法正常进行.     

适合联醇或单醇的变换工艺

对甲醇生产变换工艺的配置进行了讨论;结合国内外实际工况,分析了在低汽气比条件下中变催化剂的过度还原问题;从工艺流程、设备配置、工业应用等方面阐述了适合于联醇或单醇生产的低温变换工艺。     

均温型甲醇合成塔在大型甲醇装置中的应用

介绍了Φ3000mm均温型合成塔在200kL／a甲醇装置上的运行情况。两年来的实际运行情况表明,均温型合成塔具有床层温度分布均匀、操作弹性大、CO单程转化率高（〉75％）、结构简单等特点,应用前景广阔。     

低温甲醇洗甲醇再生塔的除垢研究

低温甲醇洗甲醇再生塔垢样坚硬，机械清洗困难，通过试验确定了一种复合化学清洗剂配方（碱性物 SAA 有机溶剂 络合剂），除垢完全，有较好的使用价值。     

联醇生产废液中甲醇的回收

选用新型填料塔,对联醇生产中排放残液采用汽提法进行处理,不仅可以回收甲醇,而且减少了残液排放造成的环境污染。该工艺简单,投资少,见效快。     

低温甲醇洗甲醇消耗高及甲醇水塔问题分析及对策

首先,针对装修跑冒滴漏,废水外送损失与气相夹带所导致的低温甲醇洗甲醇消耗高的问题,采取了强化检测力度,调整工艺指标与设备改造调整等多种方式,改善低温甲醇洗甲醇消耗高的问题。其次,对甲醇水塔中存在的液泛问题,塔盘较脏以及灵敏板上下温度差较高等多种问题进行分析与探讨,并提出优化对策,希望能有效提升生产效率及生产水平。