天然气制甲醇装置能耗分析与节能途径探讨

优化甲醇装置的能耗,不仅可以增加生产企业的经济利益,还能减少对环境的污染,达到节能减耗的生态意义,符合社会发展的目标。天然气制造技术已经有了一定的优化成效,市场需求依旧是供不应求,所以在节能减排提高生产量的潜在需求,发展空间较大。     

煤制甲醇工艺设备及能耗分析

随着经济的发展,煤炭能源的损耗逐渐增多,对环境造成了严重的污染。为了减少环境污染,煤制甲醇开始广泛运用。但是,目前的煤制甲醇工艺能耗过多。基于这个现状,分析了煤制甲醇工艺设备以及能耗,并提出一定的政策建议,希望减少煤制甲醇工艺的能耗。     

天然气制甲醇工艺研究进展

甲醇是最常见的也是最基本的有机化合物,也是常用的有机化工原料,合成中的应用也十分的广泛,其既可以作为有机溶剂,也可以作为反应原料,近年来,随着甲醇应用技术的发展以及甲醇工业的不断进步,尤其近年来甲醇作为汽车燃料的运用促使甲醇精馏技术的不断进步,甲醇及其衍生品作为新能源的宠儿得到的了越来越广泛的运用[1],大量的煤基甲醇的装置与设备不断在建或已经建立,随着甲醇需求量的不断增强。其中天然气制甲醇的工艺最为常用,本文对近年来合成甲醇的工艺进行介绍和分析,通过对天然气制备甲醇工艺的研究并且对天然气的成分对制备甲醇合成生产的影响,并且对甲烷转化甲醇过程中的催化剂影响进行了分析,以此对甲醇制备研究工艺进展进行了细致研究。     

天然气制甲醇装置的清洁生产水平评估

如何判定甲醇装置的清洁生产水平是开展甲醇装置清洁生产审核工作的重要内容之一,可基于资源能源利用指标和HJ/T 425—2008《清洁生产标准制订技术导则》分别进行评估。通过对某企业天然气制甲醇装置的清洁生产水平评估表明,该套甲醇装置的清洁生水平产已处于国内先进值水平,但其综合能耗与其基准值之间存在0.04GJ的差距。     

天然气制甲醇的物料关系分析

以转化气中一氧化碳、二氧化碳含量为变量建立天然气转化的摩尔反应方程,分析天然气蒸汽转化及纯氧转化工艺的转化气量/天然气量、蒸汽分解率、转化气中氢含量及甲烷含量与转化气中一氧化碳、二氧化碳含量之间的关系。     

天然气制甲醇工艺优化

以中海石油建滔化工有限公司日产2 000t甲醇装置为例,在以高CO_2、高N_2含量的天然气为原料的天然气制甲醇工艺中,从天然气转化和甲醇合成两个重要工序入手,重点论述了水碳比、转化炉出口温度、合成催化剂温度优化操作等关键指标对产量、能耗的影响,并阐述了日常操作和非正常工况下重点工艺指标的监控标准,达到甲醇稳定生产,增加产量,节能降耗的目的,进而取得更大的经济效益。     

基于煤制甲醇工艺设备及能耗分析

伴随着我国经济以及科学技术的不断进步,我国各行业在现阶段的发展中得到了更多的技术、物力以及人力的支持,而人们的生活水平也得到了显著的提升。我国各类工厂经过近几年的发展都得到了较大的进步,这也导致我国在现阶段发展中对于煤炭等资源的需求量极大增加,主要是因为煤炭资源是现阶段工厂发展的主要资源,但是由于近几年的过度开采,导致我国的生态环境恶化,而煤制甲醇能够在一定程度上解决这一问题,主要介绍了现阶段煤制甲醇工序以及相关的设备能耗,并分析了完善煤制甲醇工艺的相关措施,希望能促进我国煤制甲醇行业的发展。     

天然气制甲醇合成气转化工艺研究

甲醇是常见的有机化合物,作为工业常用的有机化工原料,在天然气合成制气应用中十分广泛,在甲醇应用技术的不断推动下,推动甲醇工业发展进步。基于此,阐述了天然气制甲醇工艺研究进展,并具体分析合成气制甲醇工艺,重点探究天然气制甲醇合成气转化工艺研究,以期为甲醇合成气转化工艺技术提供参考,更好地推动天然气制甲醇工艺技术的发展。     

天然气制甲醇装置工艺优化

天然气作为甲醇制品的重要生产原料,在甲醇生产过程中起到了重要的作用。以中海石油化学股份有限公司为例,分析了其80万t甲醇装置的工艺流程,涉及装置的设计、开停车管理、运行、检修等环节,分析了整个生产的优化,以实现节能减排的目标。     

一种新的利用LNG冷能的回收油田伴生气凝液的工艺

A novel process to recovery natural gas liquids from oil field associated gas with liquefied natural gas (LNG)cryogenic energy utilization is proposed.Compared to the current electric refrigeration process,the proposed process uses the cryogenic energy of LNG and saves 62.6%of electricity.The proposed process recovers ethane, liquid petroleum gas(propane and butane)and heavier hydrocarbons,with total recovery rate of natural gas liquids up to 96.8%.In this paper,exergy analysis and the energy utilization diagram method(EUD)are used to assess the new process and identify the key operation units with large exergy loss.The results show that exergy efficiency of the new process is 44.3%.Compared to the electric refrigeration process,exergy efficiency of the new process is improved by 16%.The proposed process has been applied and implemented in a conceptual design scheme of the cryogenic energy utilization for a 300 million tons/yr LNG receiving terminal in a northern Chinese harbor.     

合成气净化单元能耗计算方法

为了对某煤制烯烃全厂能量系统进行优化研究,提出基于单元、子系统和全局分段递进协同优化的策略,首先对全厂各个单元进行能耗计算和节能分析。在对合成气净化单元进行能耗分析和计算时,发现目前合成气净化单元粗合成气中夹带水蒸气的折标系数没有统一的基准,因此对合成气净化单元能耗计算方法进行了探索研究,提出了合成气净化单元能耗计算方法,规定了粗合成气中夹带水蒸气的折标系数选取方法以及单位能耗计算的基准。结果表明:提出的方法能较好地反映合成气净化单元的能效水平,并为合成气净化单元对标分析提供统一计算基准,为合成气净化单元能耗计算标准制定提供参考。     

川西北甲醇装置高能耗原因与对策

设计工况下开工锅炉不能停运,开工过程中燃料消耗和放空损失大是造成川西北甲醇装置天然气和锅炉水消耗上升的主要原因。通过调整蒸气系统操作参数,更换换热设备和甲醇合成触媒,改造转化炉燃料气流程,缩短合成触媒倒入合成新鲜气时间的整改措施,解决了运行和开工过程中天然气和锅炉水消耗高的问题。     

Computer-aided process intensification of natural gas to methanol process

The recent revolution in shale gas has presented opportunities for distributed manufacturing of key commodity chemicals, such as methanol, from methane. However, the conventional methane-to-methanol process is energy intensive which negatively affects the profitability and sustainability. We report an intensified process configuration that is both economically attractive and environmentally sustainable. This flowsheet is systematically discovered using the building block-based representation and optimization methodology. The new process configuration utilizes membrane-assisted reactive separations and can have as much as 190% higher total annual profit compared to a conventional configuration. Additionally, it has 57% less CO₂-equivalent greenhouse gas emission. Such drastic improvement highlights the advantages of building block-based computer-aided process intensification method.     

降低甲醇生产装置天然气消耗的技术措施

在天然气生产甲醇的工业过程中,合理选用高效NC306型合成催化剂,可使甲醇合成转化率提高5%;通过控制转化炉烟气氧含量在2%~2.5%,维持炉膛负压在-3~-4 mm H2O,燃料气压力由0.20 MPa提高至0.24 MPa等方法,可提高转化炉的的热效率1%~2%,降低燃料天然气的消耗量170 Nm3/h;锅炉水排污量由5%降低至2%,废锅可增加蒸汽产量约1.3 t;转化反应水碳比由3.7降低至3.5,可减少工艺蒸汽约1.5 t。另外,进行转化输气总管和废热锅炉的技术改造,降低合成、精馏的冷后温度以及回收塔底水的甲醇含量,减少系统加工损失,也可提高甲醇产量,从而降低天然气的消耗量。     

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%。     

城市天然气月用量的预测方法

基于城市天然气用量具有"有限制增长"特点以及以12个月为周期变化的规律建立城市月用气量预测模型,分析不同类型城市预测模型的相关参数,并进行实例应用。结果表明,基于逻辑斯蒂原理以及月用气量变化分布曲线函数建立的城市月用气量预测模型可以很好地表征城市月用气量的增长过程特点和周期变化规律;不同类型城市的月用气量变化分布曲线特征值及其变化范围各异,而且高峰点前后曲线宽度不同。集中采暖类城市月用气量高峰特征值与低谷特征值相差较大,非集中采暖类城市月用气量高峰特征值与低谷特征值相近,完全生产类城市月用气量具有明显的个体特点。     

中煤龙化化工公司煤气、甲醇和天然气装置实际产能评估及运行评价

介绍了中煤龙化化工公司煤制气、甲醇和天然气装置的实际产能情况,并对装置运行现状进行描述和评价,提出了提高装置运行效率以及增加企业效益的几点建议。     

Using evolutionary search to optimise the energy consumption for natural gas liquefaction

Liquefaction of natural gas is a highly energy intensive process. Therefore its energy optimisation is an important matter. Sequential Quadratic Programming (SQP) will often be the preferred method for solving these optimisation problems, but there are some obstacles due to the fact that they use the local shape of the functions. Evolutionary search could be a way of getting around these problems and in this work, evolutionary search methods were combined and adapted to the liquefaction problem. The research focused on how to efficiently use all the function evaluations to obtain robust convergence, leading to the concept of diversity; and secondly how to deal with the infeasible individuals. Tests were performed on a benchmark function to assess the effect of different methods from the literature and the parameters which control them. Finally an application to the process simulator showed satisfactory results which were less than 5% from the assumed optimal solution.     

A power plant for integrated waste energy recovery from liquid air energy storage and liquefied natural gas

Liquefied natural gas(LNG)is regarded as one of the cleanest fossil fuel and has experienced significant developments in recent years.The liquefaction process of natural gas is energy-intensive,while the regasification of LNG gives out a huge amount of waste energy since plenty of high grade cold energy(-160℃)from LNG is released to sea water directly in most cases,and also sometimes LNG is burned for regasification.On the other hand,liquid air energy storage(LAES)is an emerging energy storage tech-nology for applications such as peak load shifting of power grids,which generates 30％-40％of compres-sion heat(～200℃).Such heat could lead to energy waste if not recovered and used.The recovery of the compression heat is technically feasible but requires additional capital investment,which may not always be economically attractive.Therefore,we propose a power plant for recovering the waste cryo-genic energy from LNG regasification and compression heat from the LAES.The challenge for such a power plant is the wide working temperature range between the low-temperature exergy source(-160℃)and heat source(～200℃).Nitrogen and argon are proposed as the working fluids to address the challenge.Thermodynamic analyses are carried out and the results show that the power plant could achieve a thermal efficiency of 27％and 19％and an exergy efficiency of 40％and 28％for nitrogen and argon,respectively.Here,with the nitrogen as working fluid undergoes a complete Brayton Cycle,while the argon based power plant goes through a combined Brayton and Rankine Cycle.Besides,the economic analysis shows that the payback period of this proposed system is only 2.2 years,utilizing the excess heat from a 5 MW/40MWh LAES system.The findings suggest that the waste energy based power plant could be co-located with the LNG terminal and LAES plant,providing additional power output and reducing energy waste.