CN100348563C - Hydrocarbon synthesis process using pressure swing reforming - Google Patents
Hydrocarbon synthesis process using pressure swing reformingDownload PDFInfo
- Publication number
- CN100348563C CN100348563CCNB200480005308XACN200480005308ACN100348563CCN 100348563 CCN100348563 CCN 100348563CCN B200480005308X ACNB200480005308X ACN B200480005308XACN 200480005308 ACN200480005308 ACN 200480005308ACN 100348563 CCN100348563 CCN 100348563C
- Authority
- CN
- China
- Prior art keywords
- gas
- zone
- steam
- conversion
- pressure
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Landscapes
- Hydrogen, Water And Hydrids (AREA)
Abstract
Description
Translated fromChinese发明领域field of invention
本发明涉及从合成气合成烃类的工艺改进。更特别，本发明涉及一种工艺方案，其中在循环的填充床操作中生产合成气，其中在比再生循环压力更高的压力下实施合成气生产的转化循环，其中来自烃类合成工艺的轻气体和蒸汽用于转化循环。The present invention relates to process improvements for the synthesis of hydrocarbons from synthesis gas. More particularly, the present invention relates to a process scheme in which synthesis gas is produced in a cyclic packed bed operation, wherein the conversion cycle for synthesis gas production is carried out at a higher pressure than the regeneration cycle pressure, wherein light from the hydrocarbon synthesis process Gases and steam are used in reforming cycles.
发明背景Background of the invention
传统合成气生产方法包括水蒸气转化、气相部分氧化和自热转化制氢。这些过程的每一个当彼此比较时都具有优点和缺点。Traditional synthesis gas production methods include steam reforming, gas-phase partial oxidation, and autothermal reforming for hydrogen production. Each of these processes has advantages and disadvantages when compared to each other.
在蒸汽转化过程中，蒸汽与包含碳氢化合物的进料起反应生产富氢的合成气。对于甲烷举例说明的总的化学计量是：In a steam reforming process, steam is reacted with a hydrocarbon-containing feed to produce a hydrogen-rich synthesis gas. The overall stoichiometry illustrated for methane is:
CH4+H2O---→CO+3H2(1)CH4 +H2 O---→CO+3H2 (1)
通常，使用过量的蒸汽以使平衡向右移动。当应用于氢制造时，过量蒸汽同样能增加水煤气变换反应：Typically, excess steam is used to shift the balance to the right. When applied to hydrogen production, excess steam can also increase the water gas shift reaction:
CO+H2O--->CO2+H2(2)CO+H2 O--->CO2 +H2 (2)
由于反应的高吸热性，水蒸气转化通常在大的炉子中进行，其中催化剂被装填到管中。管子必须耐得住生产合成气的高压，同时在接近1000℃温度下传热。如斯坦福研究所国际报告No.148(1995)中描述，蒸汽转化过程效率，定义为产品合成气的燃烧热除以转化原料和炉用燃料的燃烧热，大约为79％，而空速，定义为每小时C1当量进料的标准化立方英尺/英尺3的催化剂床，为690hr-1。令人遗憾的是，水蒸气转化炉占有非常大体积的空间，比管的体积大数量级，因此低的生产率限制了工艺的经济竞争性。Due to the highly endothermic nature of the reaction, steam reforming is usually carried out in large furnaces where the catalyst is packed into the tubes. The tubes must withstand the high pressures involved in producing syngas while transferring heat at temperatures approaching 1,000°C. As described in Stanford Research Institute International Report No.148 (1995), the steam reforming process efficiency, defined as the heat of combustion of the product syngas divided by the heat of combustion of the reforming feedstock and furnace fuel, is about 79%, while the space velocity, defined as The normalized cubic feet percubic foot of catalyst bed, which is C1 equivalent feed per hour, is 690 hr−1 . Unfortunately, steam reformers occupy a very large volume of space, orders of magnitude larger than the volume of the tubes, and thus low production rates limit the economic competitiveness of the process.
气相部分氧化包括在气相中包含碳氢化合物进料的部分氧化。原料组分引入炉燃烧器中，其中它们与不足化学计量的氧燃烧生产合成气混合物。对于甲烷作为举例说明，理想气体相的部分氧化反应为：Gas phase partial oxidation includes partial oxidation of a feedstock comprising hydrocarbons in the gas phase. The feedstock components are introduced into a furnace burner where they are combusted with substoichiometric oxygen to produce a synthesis gas mixture. For methane as an example, the ideal gas phase partial oxidation reaction is:
CH4+1/2O2--->CO+2H2(3)CH4 +1/2O2 --->CO+2H2 (3)
然而，气相反应动力学往往过氧化一些原料，导致产生过热和大量的H2O、CO2和作为煤烟离开反应器的未反应的碳氢化合物。However, gas phase reaction kinetics tend to overoxidize some of the feedstock, resulting in superheating and large amounts ofH2O ,CO2 and unreacted hydrocarbons that leave the reactor as soot.
由于这些原因，当气相部分氧化化学作用施加到清洁原料时，优选向原料中加入蒸汽并向气相部分氧化反应器容器的底部中加入水蒸气转化催化剂床。气相部分氧化和水蒸气转化的结合被称作自热转化制氢。从气相部分氧化反应产生的多余的热量原位提供蒸汽转化需要的热量。For these reasons, when gas phase partial oxidation chemistry is applied to a clean feedstock, it is preferred to add steam to the feedstock and a bed of steam reforming catalyst into the bottom of the gas phase partial oxidation reactor vessel. The combination of gas-phase partial oxidation and steam reforming is called autothermal reforming for hydrogen production. The heat required for steam reforming is provided in situ by the excess heat generated from the gas phase partial oxidation reaction.
自热转化制氢比水蒸气转化基本上更紧凑，因为不使用炉子提供反应热。当前开发的用于气油供电的燃料电池车辆的自热转化制氢的实施方式利用催化部分氧化步骤，所述的步骤使自热转化制氢工艺甚至更紧凑。自热转化制氢反应器的热效率通常在90％的范围内。尽管基于催化部分氧化的自热转化制氢具有高产量(气体时空速度以C1-当量计大约为104)，但常规的基于部分氧化的自热转化制氢具有类似水蒸气转化(约103hr-1)的空速。然而，自热转化制氢需要氧源。在燃料电池车辆情况下，通常作为低压缩空气提供的氧导致氮稀释的低压力合成气，同时在炼油厂或者化学制品的实施方式中，氧通常作为精制O2提供，空气分离的成本大于自热转化制氢工艺的成本。Hydrogen production by autothermal reforming is substantially more compact than steam reforming because no furnace is used to provide the heat of reaction. Embodiments currently being developed for autothermal reformation hydrogen production for gas-oil powered fuel cell vehicles utilize a catalytic partial oxidation step that makes the autothermal reformation hydrogen production process even more compact. Thermal efficiencies of autothermal reforming hydrogen reactors are typically in the range of 90%. Although autothermal hydrogen production based on catalytic partial oxidation has a high yield (gas hourly space velocity of about 104 on a C1 -equivalent basis), conventional autothermal hydrogen production based on partial oxidation has a similar water vapor conversion (about 103 hr-1 ) airspeed. However, autothermal conversion of hydrogen requires an oxygen source. In the case of fuel cell vehicles, oxygen typically provided as low-compressed air results in nitrogen-diluted low-pressure syngas, while in refinery or chemical implementations oxygen is typically provided as refinedO2 , the cost of air separation is greater than that of Costs of the thermal conversion hydrogen production process.
Sederquist的(U.S.4,200,682、4,240,805、4,293,315、4,642,272和4,816,353)教导一种蒸汽转化过程，其中通过在循环的氧化和转化阶段之间进行循环在床之内提供转化热。如Sederquist描述，在转化床之内高质量的热量回收导致约97％的理论效率。然而这些专利中描述的实施例和工业方案在极低生产率下操作，空速约95hr-1(作为C1当量)。而且，该方法需要压缩机以将产品合成气压缩到烃合成实用的压力。Sederquist (US 4,200,682, 4,240,805, 4,293,315, 4,642,272 and 4,816,353) teaches a steam reforming process in which the heat of conversion is provided within the bed by cycling between the oxidation and reforming stages of the cycle. High quality heat recovery within the reformer bed leads to a theoretical efficiency of about 97%, as described by Sederquist. However the examples and industrial schemes described in these patents operate at very low production rates, with a space velocity of about 95 hr-1 (as Ciequivalents ). Furthermore, the process requires a compressor to compress the product synthesis gas to a practical pressure for hydrocarbon synthesis.
最近已经发现以循环填充床操作用于生产合成气的高效和高生产能力的工艺。在该工艺中，转化步骤包括将第一区预热到约700℃～2000℃的入口温度，然后引入20℃～600℃含碳氢化合物进料以及蒸汽，任选将CO2引入到第一区的入口。该反应物刚一引入，碳氢化合物就在第一区的催化剂上转化为合成气。该合成气然后从第一区通到第二区，其中气体被冷却到接近于碳氢化合物进料的入口温度的温度。当合成气离开第二区入口时进行回收。An efficient and high-capacity process for the production of synthesis gas operating in a circulating packed bed has recently been discovered. In this process, the conversion step includes preheating the first zone to an inlet temperature of about 700°C to 2000°C, and then introducing a hydrocarbon-containing feed at 20°C to 600°C and steam, optionally introducing CO2 into the first zone. Entrance to the district. Once the reactants are introduced, the hydrocarbons are converted to synthesis gas over the catalyst in the first zone. The synthesis gas is then passed from the first zone to the second zone, where the gas is cooled to a temperature close to the inlet temperature of the hydrocarbon feed. Syngas is recovered as it exits the second zone inlet.
当气体引入到第二区的入口时再生步骤开始。通过第二区积存的热量加热气体到该区的高温，并将热量载带返回第一区。最后，含氧气体和燃料在接近两区的分界面处燃烧，产生的热烟道气体移动越过第一区，因此将所述的区再加热到足够高的转化进料的温度。一旦热量再生完成，循环完成，转化再一次开始。The regeneration step begins when gas is introduced into the inlet of the second zone. The heat accumulated by the second zone heats the gas to the high temperature of that zone and carries the heat back to the first zone. Finally, the oxygen-containing gas and fuel are combusted near the interface between the two zones, and the resulting hot flue gases move across the first zone, thus reheating said zone to a temperature high enough to convert the feed. Once heat regeneration is complete, the cycle is complete and conversion begins again.
该工艺的一个优点是具有在比再生步骤更高的压力下操作转化步骤的能力，因此产生变压，产生高压合成气体。An advantage of the process is the ability to operate the conversion step at a higher pressure than the regeneration step, thus creating a pressure swing, producing high pressure synthesis gas.
用于从合成气生产液体和气态烃类产品的工艺是已知的。这些包括Fischer-Tropsch合成、甲醇合成和加氢醛化。这些工艺的每一个是放热过程，最好在H2:CO摩尔比率约为2下操作。Processes for producing liquid and gaseous hydrocarbon products from synthesis gas are known. These include Fischer-Tropsch synthesis, methanol synthesis and hydroformylation. Each of these processes is exothermic and is best operated at aH2 :CO molar ratio of about 2.
F-T合成通常使用钴或者铁催化剂，在200℃～450℃温度及10～300大气压的压力下进行。碳氢化合物产物大致相当于全石蜡天然的石油，主要包括直链、饱和化合物烷烃、一些烯烃、小于约1％的醇、脂肪酸及其他含氧化合物。F-T synthesis usually uses cobalt or iron catalysts at a temperature of 200°C to 450°C and a pressure of 10 to 300 atmospheres. The hydrocarbon products roughly correspond to fully paraffinic natural petroleum and consist primarily of linear, saturated alkanes, some alkenes, less than about 1% alcohols, fatty acids, and other oxygenates.
甲醇合成通常使用铜-氧化锌-氧化铝催化剂，在约50-100大气压的压力及约200℃-300℃温度下进行。甲醇合成的副产物包括醚、甲酸盐、酮、碳氢化合物和高级醇。Methanol synthesis is typically performed using a copper-zinc oxide-alumina catalyst at a pressure of about 50-100 atmospheres and a temperature of about 200°C-300°C. The by-products of methanol synthesis include ethers, formates, ketones, hydrocarbons and higher alcohols.
加氢醛化包括烯烃与CO和H2的反应，通常在液相、在金属羰基催化剂存在下，在50℃～200℃温度及10～200大气压的压力下进行。Hydroformylation involves the reaction of olefins with CO andH2 , usually in the liquid phase, in the presence of metal carbonyl catalysts, at temperatures ranging from 50°C to 200°C and pressures ranging from 10 to 200 atmospheres.
实际应用合成气生产技术或者烃类转化过程的任一种取决于上游和下游过程系统如何联合为总的工艺方案。如下所述及在该权利要求中定义的本发明解决实际的工艺设计和运行要求，实现变压转化与下游烃类转化有效的一体化，提供了意想不到的优点。The practical application of either syngas production technology or hydrocarbon conversion process depends on how the upstream and downstream process systems are integrated into the overall process scheme. The invention as described below and defined in this claim addresses the practical process design and operating requirements to achieve effective integration of pressure swing conversion with downstream hydrocarbon conversion, providing unexpected advantages.
发明内容Contents of the invention
在一个方面，本发明提供使用合成气的放热烃类合成工艺的改进，其中改进包括使变压转化与这样的合成工艺联合，由此实现对于常规转化的热量和物料效率。因此，在一个实施方式中，从合成气中除去至少一些在变压转化过程中产生的一些氢，与空气一起燃烧提供变压转化过程再生步骤的热量。在另外的实施方式中，用水冷却放热合成工艺以产生蒸汽用于变压转化。In one aspect, the present invention provides improvements to exothermic hydrocarbon synthesis processes using synthesis gas, wherein the improvements include integrating pressure swing conversion with such synthesis processes, thereby achieving thermal and material efficiencies over conventional conversions. Thus, in one embodiment, at least some of the hydrogen produced during the pressure swing reforming process is removed from the syngas and combusted with air to provide heat for the regeneration step of the pressure swing reforming process. In other embodiments, the exothermic synthesis process is cooled with water to generate steam for pressure swing reforming.
本发明的优选实施方式包括：Preferred embodiments of the invention include:
(a)将包括碳氢化合物和蒸汽的原料流引入通过含床填料和水蒸气转化催化剂第一区的第一端，以在第一压力下生成含H2∶CO比大于2∶1的产物合成气物流，(a) introducing a feed stream comprising hydrocarbons and steam into a first end of a first zone through a bed containing packing and a steam reforming catalyst to produce a product comprising aH2 :CO ratio greater than 2:1 at a first pressure Syngas stream,
(b)将至少一部分步骤(a)的产物通过含床填料的第二区，将显热从该产物传递到填料中；(b) passing at least a portion of the product of step (a) through a second zone comprising a bed of packing, transferring sensible heat from the product to the packing;
(c)从所述的第二区除去基本上所有的产物；(c) removing substantially all product from said second zone;
(d)将含氧气体引入所述的第二区的第二端；(d) introducing an oxygen-containing gas into the second end of said second zone;
(e)使所述的含氧气体与燃料接触，在所述的区之内，在比第一压力低的第二压力下燃烧所述的气体和燃料，因此将所述的第一区再加热到转化温度，产生烟道气通过所述的第一区的第一端离开。(e) contacting said oxygen-containing gas with a fuel, combusting said gas and fuel in said zone at a second pressure lower than the first pressure, thereby resetting said first zone Heating to the conversion temperature produces flue gas which exits through the first end of the first zone.
(f)从在步骤(c)回收的产物中分离足够的氢以生成H2∶CO比约为2∶1的合成气物流；(f) separating sufficient hydrogen from the product recovered in step (c) to generate a synthesis gas stream having aH2 :CO ratio of about 2:1;
(g)使用分离的步骤(b)的氢作为在步骤(e)的燃料；和(g) using the separated hydrogen of step (b) as fuel in step (e); and
(h)将步骤(f)的合成气引入烃类合成反应器在其中转化为液体产物。(h) introducing the synthesis gas of step (f) into a hydrocarbon synthesis reactor where it is converted to a liquid product.
以下详细说明本发明的实施方式。Embodiments of the present invention will be described in detail below.
附图简述Brief description of the drawings
图1a和1b是说明变压转化基本的转化和再生步骤的示意图。Figures 1a and 1b are schematic diagrams illustrating the basic conversion and regeneration steps of pressure swing conversion.
图2是使用热交换的基本的两个循环的变压转化过程示意图。Figure 2 is a schematic diagram of a basic two cycle pressure swing conversion process using heat exchange.
图3到5是使用变压转化和烃类合成的工艺方案的示意图。Figures 3 to 5 are schematic illustrations of process schemes using pressure swing conversion and hydrocarbon synthesis.
详细描述A detailed description
在图1中描述基本的两步循环的变压转化。现在参考图1a和1b，第一区或者转化区(1)称作变化床转化器，第二区或者同流换热区称作合成气同流换热器(7)。两个区的床都包括填料，而转化床(1)包括水蒸气转化催化剂。尽管举例说明独立的转化和同流换热区，但公认变压转化装置可能包含单一反应器。The basic two-step cycle of pressure swing conversion is depicted in FIG. 1 . Referring now to Figures 1a and 1b, the first zone or conversion zone (1) is called a variable bed converter and the second zone or recuperator zone is called a syngas recuperator (7). The beds of both zones comprise packing, while the reforming bed (1) comprises a water vapor reforming catalyst. Although separate reforming and recuperation zones are illustrated, it is recognized that a pressure swing reforming unit may comprise a single reactor.
如图1a所示，在该循环第一步开始时，同样称作转化步骤，转化区(1)处于高温，同流换热区(7)处于比转化区(1)较低的温度。含碳氢化合物的原料通过导管(15)与蒸汽一起引入转化区(1)的第一端(3)。碳氢化合物可能是任何经历吸热水蒸气转化反应的物料，包括甲烷、石油气、石油馏分、煤油、喷气燃料、燃料油、加热油、柴油和粗柴油和气油。优选，碳氢化合物是气态材料包括甲烷和其他通常为气相的碳氢化合物。优选，蒸汽以与碳氢化合物成比例的量存在，导致蒸汽与碳的比例为约1～约3(仅考虑在碳氢化合物中的碳，不考虑可能存在的CO或者CO2物种的碳)。As shown in Figure 1a, at the beginning of the first step of the cycle, also called the reforming step, the reforming zone (1) is at a high temperature and the recuperation zone (7) is at a lower temperature than the reforming zone (1). A hydrocarbon-containing feedstock is introduced into the first end (3) of the reforming zone (1 ) through conduit (15) together with steam. A hydrocarbon may be any material that undergoes a heat-absorbing vapor reforming reaction, including methane, petroleum gas, petroleum fractions, kerosene, jet fuel, heating oil, heating oil, diesel and gas oil, and gas oil. Preferably, the hydrocarbons are gaseous materials including methane and other normally gaseous hydrocarbons. Preferably, the steam is present in an amount proportional to the hydrocarbons, resulting in a steam to carbon ratio of about 1 to about 3 (only carbon in the hydrocarbons is considered, not carbon of CO orCO species that may be present) .
原料流从该床吸收热量，经由催化剂和热量转化为合成气。随该步骤进行，基于该系统传热性能形成温度变化图(23)。当床设计有足够换热能力时，如本发明描述，该曲线具有相对陡的温度梯度，所述的温度梯度随该步骤进行跨越过该转化区(1)。The feed stream absorbs heat from the bed and is converted to synthesis gas via the catalyst and heat. As this step proceeds, a temperature change map (23) is formed based on the heat transfer performance of the system. When the bed is designed with sufficient heat exchange capacity, as described in the present invention, the curve has a relatively steep temperature gradient across the conversion zone (1 ) as the step proceeds.
合成气离开转化床(1)通过在高温下的第二端(5)，并通过同流换热区(7)进入通过第一端(11)，在第二端(9)处离开。同流换热区(7)最初处于比转化区(1)较低的温度。当合成气通过同流换热区(7)时，合成气冷却到接近基本上在第二端(9)的区的温度，所述的温度大约与该循环第二步骤期间通过导管(19)引入的再生原料的温度相同(例如约20℃～600℃)。当合成气在该同流换热区(7)冷却时，产生温度梯度(24)，并在该步骤期间移动越过同流换热区(7)。Syngas leaves the reformer bed (1) through the second end (5) at high temperature and enters through the recuperation zone (7) through the first end (11) and exits at the second end (9). The recuperation zone (7) is initially at a lower temperature than the conversion zone (1). As the syngas passes through the recuperation zone (7), the syngas cools to a temperature close to that of the zone substantially at the second end (9), said temperature being approximately the same as the temperature passed through conduit (19) during the second step of the cycle The temperature of the introduced regeneration raw material is the same (for example, about 20°C to 600°C). As the syngas cools in this recuperation zone (7), a temperature gradient (24) is created and moves across the recuperation zone (7) during this step.
在步骤之间的点，温度梯度基本上移动越过转化区(1)和同流换热区(7)。区的大小要使梯度在上述转化步骤期间以可比的时间跨越过两个区。除了在各自区的出口附近存在温度梯度外，同流换热区(7)处于高温，转化区(1)处于低温。入口端(3)附近的转化区(1)的温度被冷却到接近通过导管(15)进入的碳氢化合物原料的温度(例如约20℃～约600℃)。At points between the steps, the temperature gradient moves substantially across the conversion zone (1 ) and the recuperation zone (7). The zones are sized such that the gradient traverses both zones in a comparable time during the transformation step described above. Apart from the temperature gradient near the exit of the respective zones, the recuperation zone (7) is at a high temperature and the conversion zone (1) is at a low temperature. The temperature of the conversion zone (1 ) near the inlet port (3) is cooled to approximately the temperature of the hydrocarbon feedstock entering through conduit (15) (eg, from about 20°C to about 600°C).
在实施变压转化中，有一种可选择的用于确定转化步骤结束的方法。接近转化步骤结束时，转化区端(5)的温度降低，因此转化性能劣化低于可接受的转换效率。如本发明使用的转化性能指原料碳氢化合物转化为合成气组分H2、CO和CO2的转化率。如本发明使用，术语转化率是指计算的进料含烃物种中碳转化为CO和CO2合成气物种的转化率。如本发明使用，术语未转化的产品碳氢化合物指不是合成气组份H2、CO和CO2的产品含烃物种。通常这些包括产品甲烷，及进料碳氢化合物和进料碳氢化合物的裂化产品。当转化性能劣化到低于可接受限值的水平时转化步骤结束。在实践中，整个转化和合成气利用工艺的优化将决定希望的、平均时间水平的转化的转化率。平均时间水平的转化的转化率通常大于80％、优选大于90％、最优选大于95％。In carrying out pressure swing conversion, there is an alternative method for determining the end of the conversion step. Towards the end of the conversion step, the temperature at the end (5) of the conversion zone decreases and thus the conversion performance deteriorates below acceptable conversion efficiencies. Conversion performance as used in the present invention refers to the conversion rate of feedstock hydrocarbons into the synthesis gas componentsH2 , CO andCO2 . As used herein, the term conversion refers to the calculated conversion of carbon in the feedstock hydrocarbonaceous species to CO andCO2 syngas species. As used herein, the term unconverted product hydrocarbons refers to product hydrocarbon-containing species other than the syngas componentsH2 , CO, andCO2 . Typically these include product methane, and feed hydrocarbons and cracked products of feed hydrocarbons. The conversion step is terminated when the conversion performance deteriorates to a level below acceptable limits. In practice, optimization of the overall conversion and synthesis gas utilization process will determine the conversion rate for the desired, time-averaged conversion. The conversion rate of conversion at the average time level is generally greater than 80%, preferably greater than 90%, most preferably greater than 95%.
转化步骤结束的时间点，和因此转化步骤的持续时间，可以选择(a)作为在每一转化步骤期间，对转化器不同时间性能的响应；或者(b)基于整个(平均时间)性能或者该体系；或者(c)固定作为恒定的转化步骤持续时间。在实施方式(a)中，监测至少一种与该转化性能相关联的操作特征。该特征可以是组成比如CH4、H2或者CO，或者温度比如转化床端(5)的温度。在本发明的一个实施方式中，当转化端(5)温度减小到约700℃～约1200℃的预选定温度时，转化步骤结束。在实施方式(b)中，基于测定的反映整个(时间平均)性能或者该体系的特征调节转化步骤持续时间。这可以是平均产品组成比如CH4、H2或者CO。在本发明的一个实施方式中，使用本领域已知的控制方法，基于产品中CH4时间平均浓度调节转化步骤持续时间，以缩短或者延长持续时间以实现预定目标的CH4量。在优选实施方式中，目标CH4量设置为代表约1％～约15％含烃进料碳的量。在情况(c)下，转化步骤持续时间具有固定长度，为预定的适用于操作空速的值。在本发明的一个实施方式中，转化步骤持续时间固定为约0.1秒～小于约60秒，优选为约1.0～30秒。The point in time at which the conversion steps end, and thus the duration of the conversion steps, can be chosen (a) as a response to the performance of the converter over time during each conversion step; or (b) based on overall (time-average) performance or the system; or (c) fixed as a constant conversion step duration. In embodiment (a), at least one operating characteristic associated with the conversion performance is monitored. The characteristic may be composition such asCH4 ,H2 or CO, or temperature such as the temperature at the end of the reformer bed (5). In one embodiment of the present invention, the conversion step ends when the temperature at the conversion end (5) decreases to a preselected temperature of about 700°C to about 1200°C. In embodiment (b), the duration of the conversion step is adjusted based on a measured reflective overall (time averaged) performance or characteristic of the system. This could be an average product composition such asCH4 ,H2 or CO. In one embodiment of the present invention, the duration of the conversion step is adjusted based on the time-averaged concentration of CH in the product using control methods known in the art to shorten or extend the duration to achieve a predetermined targetamount of CH. In a preferred embodiment, the targetCH4 amount is set to an amount representing from about 1% to about 15% of the hydrocarbonaceous feed carbon. In case (c), the conversion step duration has a fixed length, a predetermined value applicable to the operating space velocity. In one embodiment of the present invention, the duration of the conversion step is fixed at about 0.1 seconds to less than about 60 seconds, preferably about 1.0 to 30 seconds.
在通过位于同流换热区(7)第二端(9)的引出导管(17)收集合成气以后，第二循环步骤同样称作再生步骤开始。图解于图1b中的再生步骤基本上包括从同流换热器床(7)将热量输送到转化器床(1)。这样做，温度梯度25和26横移该床，类似于但与在转化期间的梯度23和24反方向。在优选实施方式中，含氧气体和燃料通过导管(19)引入同流换热区(7)的第二端(9)。混合物流动越过同流换热区(7)，基本上在两区(1)和(7)的分界面(13)处燃烧。在本发明中，在邻近再生区(7)和转化区(1)的分界面(13)区域发生燃烧。在本发明中，术语“邻近的区域”是指PSR床的区域，其中再生步骤燃烧实现以下两个目的：(a)加热转化区以使在再生步骤结束时，转化区端(5)的温度为至少800℃、优选至少1000℃；和(b)冷却再生区到足够的程度以使其在随后的转化步骤中发挥其接受合成气显热的功能。取决于本发明描述特定的再生实施方式，邻近分界面的区域包括0％～约50％体积的再生区(7)，及包括0％～约50％体积的转化区(1)。在本发明的优选实施方式中，大于90％的再生步骤燃烧发生在邻近分界面的区域，所述区域的体积包括小于约20％体积的同流换热区(7)，及小于约20％体积的转化区(1)。After the synthesis gas has been collected through the extraction conduit ( 17 ) at the second end ( 9 ) of the recuperation zone ( 7 ), the second cycle step, also called the regeneration step, begins. The regeneration step, illustrated in Figure 1b, essentially consists in transferring heat from the recuperator bed (7) to the converter bed (1). In doing so,
燃烧位置可以通过引入其中之一的燃烧组份，例如燃料固定在或者基本上固定在两个区(13)的分界面，而其他组份，例如含氧气体可以在同流换热区(7)的第一端(9)引入。或者，燃料和含氧气体(19)物流可以在同流换热区(7)敞口端(9)混合，穿过该区在区(13)的分界面燃烧。在该实施方式中，通过组合温度、时间、流体动力学和催化作用控制燃烧位置。燃料和氧照惯例需要温度相关的自动点火燃烧时间。在一个实施方式中，再生第一分步中非燃烧混合物的流动将决定同流换热区(7)的温度分布图，要使该区不足够热到点火，直到混合物达到该区的分界面。The combustion location can be fixed or substantially fixed at the interface of the two zones (13) by introducing one of the combustion components, such as fuel, while other components, such as oxygen-containing gas, can be in the recuperation zone (7 ) of the first end (9) introduced. Alternatively, the fuel and oxygen-containing gas (19) streams can be mixed at the open end (9) of the recuperation zone (7) and passed through the zone for combustion at the interface of zone (13). In this embodiment, the combustion location is controlled through a combination of temperature, time, fluid dynamics and catalysis. Fuels and oxygen conventionally require temperature-dependent auto-ignition burn times. In one embodiment, the flow of the non-combusting mixture in the first sub-step of regeneration will determine the temperature profile of the recuperation zone (7) such that the zone is not hot enough to ignite until the mixture reaches the interface of the zone .
转化区中催化剂的存在还可以引发在该位置的燃烧，可以增加和设计转化和同流换热区之间的空间以进一步稳定燃烧过程，并将该燃烧限制到邻近上述分界面的区域处。在又一个实施方式中，燃烧位置通过机械设计的同流换热区固定。在该设计中，燃料和含氧气体在独立通道(未示意)中前进，所述的独立通道防止燃烧直到进料在该区(13)的分界面处结合。在所述的位置，转化区的火焰稳定器(未示意)或者催化剂将保证燃烧发生。The presence of catalyst in the reforming zone can also initiate combustion at this location, and the space between the reforming and recuperating zones can be increased and designed to further stabilize the combustion process and confine this combustion to the area adjacent to the aforementioned interface. In yet another embodiment, the firing position is fixed by a mechanically designed recuperation zone. In this design, fuel and oxygen-containing gas proceed in separate channels (not shown) that prevent combustion until the feeds are combined at the interface of this zone (13). In the stated position, a flame holder (not shown) or a catalyst in the reforming zone will ensure that combustion occurs.
燃料和含氧气体的燃烧产生热烟道气体，所述的热烟道气体当移动越过转化区(1)时加热转化区(1)。烟道气然后引出通过导管(27)穿越转化区(3)的第一端。调节含氧气体/燃料混合物的组成以提供转化区要求的温度。通过改变混合物可燃物与非可燃物份额的比例调节组成由此调节温度。例如，非可燃气体比如H2O、CO2和N2可被加入到混合物中以减少燃烧温度。在优选实施方式中，通过利用蒸汽、烟道气或者贫氧空气作为混合物的一种组份得到非可燃气体。在转化器之内当热烟道气体达到该温度梯度时，梯度进一步移动越过该床。烟道气的出口温度基本上等于接近入口端(3)的转化区(1)的温度。在再生步骤开始时，出口温度基本上等于前述转化步骤转化进料的入口温度。当再生步骤进行时，随温度梯度达到端(3)，出口温度缓慢然后迅速增加，在该步骤结束时出口温度超过转化进料温度50-500℃。The combustion of the fuel and the oxygen-containing gas produces hot flue gases which heat the reforming zone (1) as they move across it. The flue gas is then led through a conduit (27) across the first end of the conversion zone (3). The composition of the oxygen-containing gas/fuel mixture is adjusted to provide the desired temperature in the conversion zone. The composition and thus the temperature are adjusted by changing the ratio of the combustible and non-combustible fractions of the mixture. For example, non-combustible gases such asH2O ,CO2 andN2 can be added to the mixture to reduce the combustion temperature. In a preferred embodiment, the non-combustible gas is obtained by utilizing steam, flue gas or oxygen-depleted air as a component of the mixture. When the hot flue gas reaches the temperature gradient within the converter, the gradient moves further across the bed. The outlet temperature of the flue gas is substantially equal to the temperature of the conversion zone (1 ) close to the inlet port (3). At the beginning of the regeneration step, the outlet temperature is substantially equal to the inlet temperature of the conversion feed to the previous conversion step. As the regeneration step proceeds, the outlet temperature increases slowly and then rapidly as the temperature gradient reaches end (3), at the end of the step the outlet temperature exceeds the conversion feed temperature by 50-500°C.
在实施变压转化中，有一种选择的方法用以确定再生步骤的结束。当足够的热量提供或者输送到转化床使转化步骤能够实施时，再生步骤结束。再生步骤结束的时间点，和因此再生步骤的持续时间，可以选择(a)作为在每一再生步骤期间，对PSR不同时间性能的响应；或者(b)基于整个(平均时间)性能或者该体系；或者(c)固定作为恒定的再生步骤持续时间。在实施方式(a)中，监测一些与该再生性能相关联的操作特征。该特征可以是组成比如O2、CH4、H2或者CO，或者温度比如转化床端(3)的温度。在本发明一个实施方式中，当转化床端(3)温度增加到约200℃～约800℃的预选定温度时，再生步骤结束。在实施方式(b)中，基于测定的反映体系整个(时间平均)性能的特征调节再生步骤持续时间。该特征可以是平均产品组成比如CH4、H2、CO或者其它的系统测量值。在本发明的一个实施方式中，基于产品中CH4的时间平均浓度，使用本领域已知的控制方法缩短或者延长持续时间以实现目标CH4量，从而调节再生步骤持续时间。在优选实施方式中，目标CH4量设置为代表约1％～约15％含烃进料碳的量。在实施方式(c)中，再生步骤持续时间具有固定长度，为预定适用于操作空速的一个值。在本发明的一个实施方式中，再生步骤持续时间固定为0.1秒～约60秒，优选1.0-30秒。在所有这些情况中，但是特别在实施方式(c)中，以类似于上述在实施方式(b)中描述的持续时间的调整方式，在该步骤期间同样优选调整再生流速以增加或者减少加到床的热量。在本发明另外的实施方式中，再生步骤持续时间固定为约1秒钟～约60秒，随着时间的推移调节再生流速以使转化产品中CH4的时间平均浓度接近设置的代表约1％～约15％含烃进料碳的目标CH4量。In implementing pressure swing conversion, there is an optional method for determining the end of the regeneration step. The regeneration step ends when sufficient heat is provided or delivered to the conversion bed to enable the conversion step. The point in time at which the regeneration step ends, and thus the duration of the regeneration step, can be chosen (a) as a response to the different temporal performance of the PSR during each regeneration step; or (b) based on the overall (average time) performance or the system ; or (c) fixed as a constant regeneration step duration. In embodiment (a), some operational characteristic associated with the regeneration performance is monitored. The characteristic could be composition such asO2 ,CH4 ,H2 or CO, or temperature such as the temperature at the end of the reformer bed (3). In one embodiment of the present invention, the regeneration step ends when the temperature at the end of the reformer bed (3) increases to a preselected temperature ranging from about 200°C to about 800°C. In embodiment (b), the duration of the regeneration step is adjusted based on a determined characteristic reflecting the overall (time-averaged) performance of the system. The characteristic could be an average product composition such asCH4 ,H2 , CO or other system measurements. In one embodiment of the invention, the regeneration step duration is adjusted using control methods known in the art to shorten or extend the duration to achieve a target amount ofCH4 based on the time-averaged concentration ofCH4 in the product. In a preferred embodiment, the targetCH4 amount is set to an amount representing from about 1% to about 15% of the hydrocarbonaceous feed carbon. In embodiment (c), the regeneration step duration has a fixed length, a value predetermined to be applicable to the operating space velocity. In one embodiment of the present invention, the duration of the regeneration step is fixed at 0.1 seconds to about 60 seconds, preferably 1.0-30 seconds. In all these cases, but especially in embodiment (c), in a manner similar to the adjustment of the duration described above in embodiment (b), it is also preferred to adjust the regeneration flow rate during this step to increase or decrease the bed heat. In an additional embodiment of the invention, the duration of the regeneration step is fixed from about 1 second to about 60 seconds, and the regeneration flow rateis adjusted over time so that the time-averaged concentration of CH in the conversion product is close to the set representative about 1% ~15% targetCH4 amount containing hydrocarbon feed carbon.
转化区现在再一次位于适于催化转化的转化温度。The conversion zone is now again at a conversion temperature suitable for catalytic conversion.
在实施本发明中，重要的是在不同的压力下操作两步循环。这是有利的，因为将空气压缩到高压是昂贵的，尽管希望具有处于高压的合成气。因此，在优选实施方式中，在比再生步骤较高的压力下进行转化步骤。因为固体和气体之间具有大的容积热容量差别，因此能够进行变压。In practicing the invention it is important to operate the two-step cycle at different pressures. This is advantageous because it is expensive to compress air to high pressure, although it is desirable to have syngas at high pressure. Therefore, in a preferred embodiment, the conversion step is carried out at a higher pressure than the regeneration step. Because of the large difference in volumetric heat capacity between solids and gases, pressure swings are possible.
变压转化操作温度和压力列于表1中。The pressure swing conversion operating temperatures and pressures are listed in Table 1.
体系的空速通常按小时计算表示为进料的标准体积气体流速除以催化剂床体积，称作气体体积空间速度或者GHSV。空速还可以依据进料的碳氢化合物组份定义。当这样定义时，对于甲烷进料的GHSV是甲烷的标准时间体积气体流速除以床体积。如本发明使用，术语空速缩写为C1GHSV，指基于C1基准的任一碳氢化合物进料的空速。正因如此，碳氢化合物进料速度计算作为碳进料的摩尔速率，及标准体积速率，所述的体积速率计算似乎碳是气态物种。例如，平均碳数为7.0的气油进料，在气态流速1,000NL/hr下进入1.0L的床，具有7,000的空速。该定义基于在转化步骤期间的进料流，其中床体积包括转化和同流换热区所有的催化剂和传热固体。The space velocity of the system is usually expressed on an hourly basis as the standard volumetric gas flow rate of the feed divided by the catalyst bed volume, referred to as the gas volumetric space velocity or GHSV. Space velocity can also be defined in terms of the hydrocarbon composition of the feed. When so defined, the GHSV for a methane feed is the standard time volumetric gas flow rate of methane divided by the bed volume. As used herein, the term space velocity is abbreviated as C1 GHSV and refers to the space velocity of any hydrocarbon feedstock on a C1 basis. As such, the hydrocarbon feed rate is calculated as the molar rate of the carbon feed, and the standard volume rate is calculated as if carbon were a gaseous species. For example, a gas oil feed with an average carbon number of 7.0, entering a bed of 1.0 L at a gaseous flow rate of 1,000 NL/hr, has a space velocity of 7,000. This definition is based on the feed stream during the reforming step, where the bed volume includes all catalyst and heat transfer solids in the reforming and recuperation zones.
在变压转化中，空速C1GSHSV通常的范围为约1,000～约50,000。In pressure swing conversion, the space velocity C1 GSHSV typically ranges from about 1,000 to about 50,000.
在优选实施方式中，变压转化在可提供足够传热速度的床填料和空速条件下进行，所述的传热速度由传热参数ΔTHT表征，为约0.1℃～约500℃，更优选为约0.5℃～40℃。参数ΔTHT是转化需要的床平均体积传热速度H与床的体积传热系数h的比例。转化需要的体积传热速度计算为空速与转化热的乘积(基于每一C1体积的热量)。例如，H＝4.9cal/cc/s＝2.2cal/cc*8000hr-1/3600s/hr，其中2.2cal/cc是每标准体积甲烷的甲烷的转化热，8000是甲烷的C1GHSV。当转化和再生步骤的持续时间可比时，两步中的值H也将是可比的。床的体积传热系数，hv，是本领域已知的，通常计算为区域基系数(例如cal/cm2s℃)和传热比表面积(av，例如cm2/cm3)的乘积，通常称为填料的浸湿面积。In a preferred embodiment, the pressure swing conversion is performed under bed packing and space velocity conditions that provide a sufficient heat transfer rate, characterized by the heat transfer parameter ΔTHT , of about 0.1°C to about 500°C, more preferably Preferably, it is about 0.5°C to 40°C. The parameter ΔTHT is the ratio of the bed average volumetric heat transfer rate H required for conversion to the bed's volumetric heat transfer coefficient h. The volumetric heat transfer rate required for conversion was calculated as the product of space velocity and heat of conversion (based on heat per C1 volume). For example, H = 4.9 cal/cc/s = 2.2 cal/cc * 8000 hr- 1 /3600 s/hr, where 2.2 cal/cc is the heat of conversion of methane per standard volume of methane and 8000 is theCi GHSV of methane. When the durations of the conversion and regeneration steps are comparable, the value H in the two steps will also be comparable. The volumetric heat transfer coefficient of a bed, hv , is known in the art and is usually calculated as the product of the area basis coefficient (e.g. cal/cm2s °C) and the heat transfer specific surface area (av , e.g. cm2 /cm3 ) , usually referred to as the wetted area of the filler.
该变压转化过程的床填料包括至少1000℃稳定的堇青石、硅酸铝、粘土、富铝红柱石、二氧化硅-氧化铝、二氧化锆等。Bed packings for the pressure swing conversion process include at least 1000°C stable cordierite, aluminum silicate, clay, mullite, silica-alumina, zirconia, and the like.
图2示意使用热交换工艺的一个实施方式。在该实施方式中，同时使用两个变压转化床系统以使一个体系转化同时另一个再生。利用多个床可提供连续流动的转化产品，尽管每一床进行循环操作。在图2中，第一床(148)用于再生步骤，而第二床(149)用于转化步骤。每一床(148和149)包括两个转化和同流换热区。在该实施方式中，使用几套阀调节不同的往返于该床的物流流动。第一套阀(157和159)控制碳氢化合物、蒸汽和任选CO2进料流动进入该床，而第二套阀(152和154)控制转化步骤的产品流动离开该同流换热区。第三套阀(151和153)调节含氧气体/燃料和任选的非燃烧气体流动进入该床，第四套阀(156和158)调节烟道气流动离开转化区。Figure 2 illustrates one embodiment using a heat exchange process. In this embodiment, two pressure swing reformer bed systems are used simultaneously so that one system is reformed while the other is regenerated. The use of multiple beds provides a continuous flow of converted product, although each bed is cycled. In Figure 2, the first bed (148) is used for the regeneration step, while the second bed (149) is used for the conversion step. Each bed (148 and 149) includes two conversion and recuperation zones. In this embodiment, several sets of valves are used to regulate the flow of different streams to and from the bed. The first set of valves (157 and 159) controls the flow of hydrocarbon, steam and optionalCO2 feed into the bed, while the second set of valves (152 and 154) controls the flow of the products of the conversion step out of the recuperation zone . A third set of valves (151 and 153) regulates the flow of oxygen-containing gas/fuel and optional non-combustion gases into the bed and a fourth set of valves (156 and 158) regulates the flow of flue gas out of the conversion zone.
在操作中，当阀151、154、156和159敞开时，阀152、153、157和158关闭。当这些阀处于所述的状态时，含氧的气体(162)和燃料(161)通过阀151进入该床(148)，同时烟道气通过阀156离开床(148)。同时，该碳氢化合物、蒸汽和任选CO2进料通过阀159进入第二床(149)，同时转化产品通过阀154离开该床(149)。在该步骤结束时，阀152、153、157和158现在敞口，阀151、154、156和159现在关闭，循环反向，第一床(148)转化进料，第二床(149)再生热量。In operation,
再看图3，其说明本发明的一个实施方式，在变压转化器(28)中生产的合成气用于烃类合成反应器(29)比如F-T(FT)反应器。变压转化过程导致形成合成气物流的H2∶CO比例为约3∶1。对于气体转化过程，希望H2∶CO的比例为约2∶1。因此，变压转化过程的合成气产物优选经分离步骤处理，其中在分离器(30)中除去一部分氢用于再生步骤。因为再生可在基本上比转化步骤低的压力下进行，所以隔膜分离器是特别优选的。如图3所示，可加入补充的碳氢化合物例如CH4用于燃料平衡。Referring again to Figure 3, which illustrates an embodiment of the present invention, the synthesis gas produced in the pressure swing converter (28) is used in a hydrocarbon synthesis reactor (29) such as a FT (FT) reactor. The pressure swing conversion process results in a H2: CO ratio of about 3:1 forming the syngas stream. For a gas shift process, aH2 :CO ratio of about 2:1 is desired. Accordingly, the syngas product of the pressure swing conversion process is preferably processed through a separation step wherein a portion of the hydrogen is removed in separator (30) for a regeneration step. Membrane separators are particularly preferred because regeneration can be performed at substantially lower pressures than the conversion step. As shown in Figure 3, supplemental hydrocarbons such as CH4 may be added for fuel balance.
在其转化步骤期间，变压转化反应器(28)加入结合的转化进料(102)，得到产物合成气(103)。在再生步骤期间，再生进料(116)进入该变压转化器中，产生烟道气产物(117)。再生进料可一起或者作为单独的燃料和空气流进入，但是出于物料平衡的目的，显示为单一的总进料(116)。热交换没有显示于图3中，但是应理解在本发明公开中及其他处也会使用，而且是本领域已知的。如果给定了物流(102、103、116、117)的条件，条件是变压转化器的进入点或者离开点。During its reforming step, the pressure swing reforming reactor (28) feeds the combined reforming feed (102), yielding a product synthesis gas (103). During the regeneration step, regeneration feed (116) enters the pressure swing converter, producing a flue gas product (117). The regeneration feeds may enter together or as separate fuel and air streams, but for mass balance purposes are shown as a single total feed (116). Heat exchange is not shown in Figure 3, but is understood to be used in this disclosure and elsewhere, and is known in the art. If a condition for a stream (102, 103, 116, 117) is given, the condition is either the point of entry or the point of exit of the pressure swing converter.
转化(103)的合成气产物具有比合成需要更高的H2/CO，并导入分离步骤(30)，其中一些过量H2作为物流(105)除去。具有适于合成的H2/CO的残余合成气(104)被导入烃类合成(HCS)反应器(29)。在该实施例中，通过钴基催化剂催化烃类合成反应以高转化生成石蜡液体(106)。尽管该实施方式显示为单一反应器，但如本领域熟知的可能使用多个反应器。另外，分离步骤包括于HCS反应器中分离水，以使有价值的高沸点组份保持为液体物流(106)，同时将低沸程组份保持在“尾气”物流(107)。在该实施例中，尾气物流(107)包括具有4个碳或者更少碳的所有的碳氢化合物，大多数是甲烷。HCS反应是放热的，因此作为加热的冷却介质(108)除去热量。HCS反应器的冷却是本领域已知的。The syngas product of conversion (103) has a higherH2 /CO than synthesis needs and is directed to a separation step (30) where some excessH2 is removed as stream (105). The residual synthesis gas (104) withH2 /CO suitable for synthesis is directed to the hydrocarbon synthesis (HCS) reactor (29). In this example, the hydrocarbon synthesis reaction is catalyzed by a cobalt-based catalyst to produce paraffinic liquid (106) at high conversion. Although this embodiment is shown as a single reactor, it is possible to use multiple reactors as is well known in the art. Additionally, the separation step includes separating water in the HCS reactor so that valuable high boiling components are kept as a liquid stream (106), while low boiling range components are kept in the "tail gas" stream (107). In this example, the tail gas stream (107) includes all hydrocarbons with 4 carbons or less, mostly methane. The HCS reaction is exothermic, so the cooling medium (108) acts as a heat to remove heat. Cooling of HCS reactors is known in the art.
在该描述的实施例(实施例1)中，在HCS尾气(107)中的一部分CO2通过分离(31)除去，得到浓缩的CO2物流(109)和贫二氧化碳的尾气物流(110)。该尾气物流(110)是减少CO2的HCS尾气，其与新鲜的天然气(101)和蒸汽(111)相结合形成结合的转化进料(102)。在该实施例中，在转化步骤结束时，该蒸汽包括少量的用于吹扫碳氢化合物和合成气变压转化器床的蒸汽。应理解在该合成气环路中需要一些压缩，因为每一步骤引出一些压降，因此在没有压缩的情况下循环合成气(110)的压力比转化器进料(102)低。如果施加到最后的尾气(110)，其体积是最小的，因此压缩是最不昂贵的。In the depicted example (Example 1), a portion of theCO in the HCS tail gas (107) is removed by separation (31), resulting in a concentratedCO stream (109) and a carbon dioxide-depleted tail gas stream (110). The off-gas stream (110) is a CO2- reduced HCS off-gas which is combined with fresh natural gas (101) and steam (111) to form a combined conversion feed (102). In this example, the steam includes a small amount of steam used to sweep the hydrocarbon and syngas pressure swing converter bed at the end of the reforming step. It will be appreciated that some compression is required in this syngas loop because each step induces some pressure drop, so the recycle syngas (110) would be at a lower pressure than the reformer feed (102) without compression. If applied to the final exhaust (110), its volume is the smallest and therefore the least expensive to compress.
在该实施例中主要使用在氢分离器(30)中除去的氢气流(105)进行变压转化器的再生。在本发明的一般使用中，一些氢可作为净化氢物流(112)用于其他应用场合。例如，H2可能用于碳氢化合物提质加工步骤。同样，一般说来，含氢物流(112)的燃烧热可能与再生需要的热量不能精确匹配，因此需要氢吹扫(112)或者补充的燃料(113)。本发明实施例包括零氢去除物(112)和少量补充的燃料(113)。在本发明实施例中结合的再生进料(116)由氢燃料(105)、少量补充的天然气(113)、新鲜空气(114)和循环烟道气(115)组成。在该实施方式中循环烟道气以减少再生气流的氧含量。排放到大气中的最后的尾气(118)是减去循环物料(115)的再生产物(117)。The regeneration of the pressure swing converter is performed in this example primarily using the hydrogen stream (105) removed in the hydrogen separator (30). In typical use of the invention, some hydrogen may be used in other applications as a purified hydrogen stream (112). For example,H2 may be used in hydrocarbon upgrading processing steps. Also, in general, the heat of combustion of the hydrogen-containing stream (112) may not exactly match the heat required for regeneration, thus requiring a hydrogen purge (112) or supplemental fuel (113). Embodiments of the invention include zero hydrogen removal (112) and a small amount of make-up fuel (113). The combined regeneration feed (116) in an embodiment of the invention consists of hydrogen fuel (105), a small amount of make-up natural gas (113), fresh air (114) and recycled flue gas (115). The flue gas is recycled in this embodiment to reduce the oxygen content of the regeneration gas stream. The final tail gas (118) vented to atmosphere is regeneration product (117) minus recycle material (115).
用于本发明实施例1实施方式的物料平衡在表2中显示为主要物流表。可见表2的物料平衡的再生压力约为2大气压。这样的压力通过空气鼓风机设备提供。再生烟道气(118)可能被导入气体膨胀机以回收可用于驱动该鼓风机的操作能量。在本发明的一个实施方式中，该鼓风机-膨胀机对机械连接以提供改进的成本或者效率。在这样一个实施方式中，PSR再生压力优选为约2～约10大气压(绝对)。The material balance for the Example 1 implementation of the present invention is shown in Table 2 as the main stream table. It can be seen that the regeneration pressure of the material balance in Table 2 is about 2 atmospheres. Such pressure is provided by air blower equipment. Regenerated flue gas (118) may be directed to a gas expander to recover operating energy that may be used to drive the blower. In one embodiment of the invention, the blower-expander pair is mechanically coupled to provide improved cost or efficiency. In such an embodiment, the PSR regeneration pressure is preferably from about 2 to about 10 atmospheres (absolute).
在本发明另外的实施方式中，通过使PSR再生系统与气体涡轮机联合提供鼓风机-膨胀器功能。通过将空气压缩到中压(7-30大气压)操作气体涡轮机，燃烧一部分所述的空气与燃料，以使空气和燃烧产物的结合物流加热到高温(900-1300℃)，然后在涡轮机中膨胀结合的物流，导致足够的机械动力以驱动压缩机，而且具有剩余功率用于发电或者其他目的。本领域已知热压缩空气可从气体涡轮机中引出用于外部工艺，在一些组成和条件变化的情况下返回该涡轮机以实现其作为燃烧稀释剂和膨胀流体的作用。In a further embodiment of the invention, the blower-expander function is provided by combining a PSR regeneration system with a gas turbine. A gas turbine is operated by compressing air to medium pressure (7-30 atmospheres), combusting a portion of said air and fuel so that the combined stream of air and combustion products is heated to high temperature (900-1300°C) and then expanded in the turbine The combined streams result in sufficient mechanical power to drive the compressor, with surplus power for power generation or other purposes. It is known in the art that hot compressed air can be drawn from a gas turbine for use in an external process and returned to the turbine to fulfill its role as a combustion diluent and expansion fluid under some compositional and conditional variation.
在本发明的优选实施方式中，再生新鲜空气(114)作为从气体涡轮机提取的空气提供，再生烟道气(118)返回气体涡轮机以满足气体涡轮机对于燃烧稀释剂和膨胀流体的需要。使用气体涡轮功率输出以同时发电或给整个过程的电驱动器要求提供动力。实施例2实施方式的物料平衡显示为表3。使用与通用电气机构9气体涡轮机联合的气流和条件制备实施例。然而，可以使用任何的涡轮机，涡轮机的选择是取决于污垢沉积物、工艺经济和希望的动力与液体产物比例的问题。In a preferred embodiment of the invention, regeneration fresh air (114) is provided as air extracted from the gas turbine and regeneration flue gas (118) is returned to the gas turbine to meet the gas turbine's needs for burning diluent and expansion fluid. Use the gas turbine power output to simultaneously generate electricity or power the electrical drive requirements of the entire process. The material balance for the Example 2 embodiment is shown in Table 3. The examples were prepared using gas flow and conditions associated with a General Electric Mechanism 9 gas turbine. However, any turbine may be used, the choice of turbine being a matter of fouling deposits, process economics and desired power to liquid product ratio.
在又一个实施方式中，如图4所示循环副产物和未转化的合成气到变压转化器，而不需要去除任何包含的CO2。另外，该实施方式使用过量空气再生，而不是实施例的空气/烟道气混合物，该实施方式使用在冷却该合成反应器中产生的蒸汽直接作为转化反应物。In yet another embodiment, the by-products and unconverted syngas are recycled to the pressure swing converter as shown in Figure 4 without removal of any containedCO2 . In addition, this embodiment uses excess air regeneration, rather than the air/flue gas mixture of the examples, and this embodiment uses the steam generated in cooling the synthesis reactor directly as the conversion reactant.
在其转化步骤期间，变压转化反应器(28)加入结合的转化进料(102)，得到产物合成气(103)。在再生步骤期间，再生进料(116)进入该变压转化器中，产生烟道气产物(117)。再生进料可一起或者作为单独的燃料和空气流进入，但是出于物料平衡的目的，显示为单一的总进料(116)。热交换没有显示于图4中，但是应理解在本发明公开中及其他处也会使用，而且是本领域已知的。如果给定了物流(102、103、116、117)的条件，条件是变压转化器的进入点或者离开点。During its reforming step, the pressure swing reforming reactor (28) feeds the combined reforming feed (102), yielding a product synthesis gas (103). During the regeneration step, regeneration feed (116) enters the pressure swing converter, producing a flue gas product (117). The regeneration feeds may enter together or as separate fuel and air streams, but for mass balance purposes are shown as a single total feed (116). Heat exchange is not shown in Figure 4, but is understood to be used in this disclosure and elsewhere, and is known in the art. If a condition for a stream (102, 103, 116, 117) is given, the condition is either the point of entry or the point of exit of the pressure swing converter.
转化(103)的合成气产物具有比合成需要更高的H2/CO，并导入分离步骤(30)，其中一些过量H2作为物流(105)除去。具有适于合成的H2/CO的残余合成气(104)被导入烃类合成(HCS)反应器(29)。在该实施例中，通过钴基催化剂催化烃类合成反应以高转化生成石蜡液体(106)。尽管该实施方式显示为单一反应器，但如本领域熟知的可能使用多个反应器。另外，分离步骤包括于HCS反应器中分离水，以使有价值的高沸点组份保持为液体物流(106)，同时将低沸程组份保持在“尾气”物流(107)。在该实施例中，尾气物流(107)包括具有4个碳或者更少碳的所有的碳氢化合物，大多数是甲烷。HCS反应是放热的，因此作为加热的冷却介质(108)除去热量。在该实施方式中，该冷却介质是水，一旦从HCS反应中吸收热量就转变为约10大气压的蒸汽(108)。The syngas product of conversion (103) has a higherH2 /CO than synthesis needs and is directed to a separation step (30) where some excessH2 is removed as stream (105). The residual synthesis gas (104) withH2 /CO suitable for synthesis is directed to the hydrocarbon synthesis (HCS) reactor (29). In this example, the hydrocarbon synthesis reaction is catalyzed by a cobalt-based catalyst to produce paraffinic liquid (106) at high conversion. Although this embodiment is shown as a single reactor, it is possible to use multiple reactors as is well known in the art. Additionally, the separation step includes separating water in the HCS reactor so that valuable high boiling components are kept as a liquid stream (106), while low boiling range components are kept in the "tail gas" stream (107). In this example, the tail gas stream (107) includes all hydrocarbons with 4 carbons or less, mostly methane. The HCS reaction is exothermic, so the cooling medium (108) acts as a heat to remove heat. In this embodiment, the cooling medium is water, which converts to steam (108) at about 10 atmospheres upon absorption of heat from the HCS reaction.
在该显示的实施例中，HCS尾气(107)与新鲜的天然气(101)和蒸汽(111)结合以制造结合的转化进料(102)。在该实施例中，蒸汽(111)的源是通过冷却HCS反应器产生的蒸汽(108)。在转化步骤结束时，用于变压转化的蒸汽(111)量包括少量的用于吹扫碳氢化合物和合成气变压转化器床的蒸汽。应理解在该合成气环路中需要一些压缩，因为每一步骤引出一些压降，因此在没有压缩的情况下循环合成气(110)的压力比转化器进料(102)低。如果施加到最后的尾气(110)，其体积是最小的，因此压缩是最不昂贵的。In the example shown, the HCS tail gas (107) is combined with fresh natural gas (101) and steam (111) to produce a combined conversion feed (102). In this example, the source of steam (111) is steam (108) generated by cooling the HCS reactor. At the end of the reforming step, the amount of steam (111) used for pressure swing reforming includes a small amount of steam for sweeping hydrocarbon and syngas pressure swing reformer beds. It will be appreciated that some compression is required in this syngas loop because each step induces some pressure drop, so the recycle syngas (110) would be at a lower pressure than the reformer feed (102) without compression. If applied to the final exhaust (110), its volume is the smallest and therefore the least expensive to compress.
在该实施例中主要使用在氢分离器(30)中除去的氢气流(105)进行变压转化的再生。在本发明的一般使用中，一些氢可作为净化氢物流(112)用于其他应用场合。例如，H2可能用于碳氢化合物提质加工步骤。同样，一般说来，含氢物流(112)的燃烧热可能与再生需要的热量不能精确匹配，因此需要氢吹扫(112)或者补充的燃料(113)。本发明实施例包括零氢去除物(112)和少量补充的燃料(113)。在本发明实施例中结合的再生进料(116)由氢燃料(105)、少量补充的天然气(113)和新鲜空气(114)组成。排放到大气中的最后的烟道气是再生产物(117)。The regeneration of the pressure swing conversion is mainly performed in this example using the hydrogen stream (105) removed in the hydrogen separator (30). In typical use of the invention, some hydrogen may be used in other applications as a purified hydrogen stream (112). For example,H2 may be used in hydrocarbon upgrading processing steps. Also, in general, the heat of combustion of the hydrogen-containing stream (112) may not exactly match the heat required for regeneration, thus requiring a hydrogen purge (112) or supplemental fuel (113). Embodiments of the invention include zero hydrogen removal (112) and a small amount of make-up fuel (113). The combined regeneration feed (116) in an embodiment of the invention consists of hydrogen fuel (105), a small amount of supplemental natural gas (113) and fresh air (114). The final flue gas vented to the atmosphere is the regeneration product (117).
本发明实施例3实施方式的物料平衡显示为表4中的主要物流表。The material balance of the embodiment of Example 3 of the present invention is shown as the main flow table in Table 4.
熟知的是F-T工艺是放热的，使用水控制温度，同时生成蒸汽(108)。如图3所示，至少一部分蒸汽(108)用于该转化器(28)。很容易地预期，在冷却烃类合成反应器中生成的蒸汽处于比变压转化器希望的转化压力更低的压力，如果那样的话，变压转化器可在生成蒸汽或者蒸汽被压缩到更高压力的压力下进行操作。It is well known that the F-T process is exothermic, using water to control the temperature while generating steam (108). As shown in Figure 3, at least a portion of the steam (108) is used in the reformer (28). It can easily be expected that the steam produced in the cooled hydrocarbon synthesis reactor is at a lower pressure than the desired conversion pressure of the pressure swing converter, in which case the pressure swing converter can either be produced or compressed to a higher Operate under pressure.
在图5显示的又一个实施方式中，从烃类合成反应器(29)回收的蒸汽(108)用于提供压缩合成气反应器蒸汽需要的动力。在该实施方式中，来自烃类合成反应器的低压蒸汽(108)在要膨胀的物流(130)到要压缩的物流(133)之间分配。在该实施方式中，在过热器(135)中加热要膨胀的物流，之后在涡轮机(32)中膨胀以产生轴输出功率。轴输出功率转动压缩机(33)，将蒸汽(133)压缩为更高的压力物流(134)用于转化步骤。In yet another embodiment shown in Figure 5, the steam (108) recovered from the hydrocarbon synthesis reactor (29) is used to provide the power needed to compress the synthesis gas reactor steam. In this embodiment, the low pressure steam (108) from the hydrocarbon synthesis reactor is divided between the stream to be expanded (130) and the stream to be compressed (133). In this embodiment, the stream to be expanded is heated in superheater (135) and then expanded in turbine (32) to produce shaft output power. The shaft output turns the compressor (33), which compresses the vapor (133) into a higher pressure stream (134) for the reforming step.
在优选实施方式中，在变压转化器中的床填料设计为要使再生可在压降小于2大气压、更优选小于1大气压下进行。本发明该实施方式优选的填料设计为在小的压降下通过大量的气体。优选的物料形状包括蜂巢式整料和壁流整料。本领域熟知的蜂巢式整料例如如描述于US3,885,977中。蜂巢式整料从定向于流动方向的长直通孔道得到它们的低压降。壁流整料同样是本领域熟知的，例如如描述于US4,276,071中。最通常，通过堵塞互生通道端，壁流整料制造为蜂巢式整料的改型物，如描述于US4,509,966中。壁流整料从定向于流动方向的长直通孔道形成它们的低压降，但是通过强制使流体通过整料的薄壁增加大度量的传热面积。In a preferred embodiment, the bed packing in the pressure swing converter is designed such that regeneration can be performed with a pressure drop of less than 2 atmospheres, more preferably less than 1 atmosphere. The preferred packing for this embodiment of the invention is designed to pass a large volume of gas with a small pressure drop. Preferred material shapes include honeycomb monoliths and wall flow monoliths. Honeycomb monoliths are well known in the art, for example as described in US 3,885,977. Honeycomb monoliths get their low pressure drop from long straight-through cells oriented in the direction of flow. Wall flow monoliths are likewise well known in the art, eg as described in US 4,276,071. Most commonly, wall flow monoliths are fabricated as a modification of honeycomb monoliths by plugging the ends of the alternating channels, as described in US 4,509,966. Wall flow monoliths develop their low pressure drop from long straight-through channels oriented in the direction of flow, but increase the heat transfer area by a large amount by forcing the fluid through the thin walls of the monolith.
在本发明中使用蜂巢式或者壁流整料的优点在于，对于给定水平的传热，这些形状可以在比颗粒填料床可能的速度更高的速度下操作。烃类合成工艺通过超大规模操作在经济上是有利的。在超大规模上，转化体积必须同样是大量的。希望通过增加床体积的总尺寸：直径和长度，提供该体积；因此提供最经济的床装置。因为压降随着长度增加，非常最大的规模需要最低的压力降装置。对于本发明，优选的蜂巢式整料的通道密度范围为约100胞腔/in2～约1600胞腔/in2(15-250胞腔/cm2)。An advantage of using honeycomb or wall flow monoliths in the present invention is that, for a given level of heat transfer, these shapes can operate at higher velocities than possible with a packed bed of particles. Hydrocarbon synthesis processes are economically advantageous by operating on a very large scale. On very large scales, the transformation volume must be equally large. It is desirable to provide this volume by increasing the overall dimensions of the bed volume: diameter and length; thus providing the most economical bed arrangement. Because pressure drop increases with length, the very largest scales require the lowest pressure drop devices. For the present invention, preferred honeycomb monoliths have channel densities ranging from about 100 cells/in2 to about 1600 cells/in2 (15-250 cells/cm2 ).
表2：在图3和实施例1中的对于选择的主要物流的流速(kg/hr)和PSR条件。Table 2: Flow rates (kg/hr) and PSR conditions for selected main streams in Figure 3 and Example 1.
表3：在图3和实施例2中的对于选择的主要物流的流速和PSR条件。Table 3: Flow rates and PSR conditions for selected main streams in Figure 3 and Example 2.
表4：在图4和实施例2中的对于选择的主要物流的流速(kg/hr)和PSR条件。Table 4: Flow rates (kg/hr) and PSR conditions for selected main streams in Figure 4 and Example 2.
Claims (15)
Translated fromChineseApplications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US45090203P | 2003-02-28 | 2003-02-28 | |
| US60/450,902 | 2003-02-28 | ||
| US10/756,651 | 2004-01-13 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1753854A CN1753854A (en) | 2006-03-29 |
| CN100348563Ctrue CN100348563C (en) | 2007-11-14 |
Family
ID=36680250
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB200480005308XAExpired - LifetimeCN100348563C (en) | 2003-02-28 | 2004-02-13 | Hydrocarbon synthesis process using pressure swing reforming |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100348563C (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8017539B2 (en)* | 2008-10-22 | 2011-09-13 | Uop Llc | Once through regeneration for an olefin cracking reactor |
| BR112015006869A2 (en)* | 2012-09-26 | 2017-07-04 | Enerkem Inc | synthesis gas separation and reform process |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN85101020A (en)* | 1984-03-09 | 1987-01-10 | 法国石油研究院 | The process of making synthesis gas by indirect oxidation of hydrocarbons |
| US20020170228A1 (en)* | 2001-03-27 | 2002-11-21 | Davis Stephen Mark | Production of diesel fuel from bitumen |
| US6512018B2 (en)* | 2000-03-28 | 2003-01-28 | Syntroleum Corporation | Hydrocarbon conversion process using a plurality of synthesis gas sources |
- 2004
- 2004-02-13CNCNB200480005308XApatent/CN100348563C/ennot_activeExpired - Lifetime
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN85101020A (en)* | 1984-03-09 | 1987-01-10 | 法国石油研究院 | The process of making synthesis gas by indirect oxidation of hydrocarbons |
| US6512018B2 (en)* | 2000-03-28 | 2003-01-28 | Syntroleum Corporation | Hydrocarbon conversion process using a plurality of synthesis gas sources |
| US20020170228A1 (en)* | 2001-03-27 | 2002-11-21 | Davis Stephen Mark | Production of diesel fuel from bitumen |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1753854A (en) | 2006-03-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4667370B2 (en) | Hydrocarbon synthesis method using pressure swing reforming | |
| US7045553B2 (en) | Hydrocarbon synthesis process using pressure swing reforming | |
| AU2004217993B2 (en) | Hydrogen manufacture using pressure swing reforming | |
| CN100345750C (en) | Hydrogen manufacture using pressure swing reforming | |
| Detchusananard et al. | Biomass gasification integrated with CO2 capture processes for high-purity hydrogen production: process performance and energy analysis | |
| RU2676062C2 (en) | Method and system for producing liquid hydrocarbon product from fischer-tropsch process using synthesis gas produced from oxygen transport membrane based reforming reactor | |
| US20060183009A1 (en) | Fuel cell fuel processor with hydrogen buffering | |
| US8945488B2 (en) | Gas-to-liquid technology | |
| Zhang et al. | Autothermal operation strategies of chemical looping processes for hydrogen generation: process simulation, parametric studies, and exergy analysis | |
| EP1601615A1 (en) | Pressure swing reforming for fuel cell systems | |
| CN1214037A (en) | Combined production method of steam conversion device and cogeneration power device | |
| WO2014085109A1 (en) | Hybrid plant for liquid fuel production and method for operating it where a gasification unit in the hybrid plant is operating at less than its design capacity or is not operational | |
| AU714133B2 (en) | Turbine-powered, Fischer-Tropsch system and method | |
| CN100348563C (en) | Hydrocarbon synthesis process using pressure swing reforming | |
| JP4850696B2 (en) | Hydrogen production using pressure swing reforming | |
| Iaquaniello et al. | Integrated membrane systems for ultrapure hydrogen production |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term | Granted publication date:20071114 |