预加氢进料换热器内漏分析

为了判断预加氢反应进料换热器(E101)是否内漏,先通过预加氢反应器出口、预加氢反应高分罐出口、预加氢汽提塔塔底出口采样,样品的硫含量分析结果分别为35.9×10^–6、75×10^–6、0.8×10^–6,表明预加氢反应器出口油样正常,预加氢反应高分罐出口、预加氢汽提塔塔底出口油样硫含量偏高,初步判断E101内漏;进一步通过E101(A-B/C-D/E-F/G)管程出口采样,样品的硫含量分析结果分别为38.6×10^–6、43.8×10^–6、49.9×10^–6、78.5×10^–6,表明E101(E-F/G)管程出口油样的硫含量偏高。由此得出结论为：E101(E-F/G)管束出现内漏。     

快速变压吸附制氢工艺的模拟与分析

目前工业上主要通过变压吸附技术从蒸汽甲烷重整气中制取氢产品气。然而,能源需求量的快速增加使得传统变压吸附技术在产量方面的不足越发明显。为此,进行了快速变压吸附从蒸汽甲烷重整气中制取氢气的模拟研究。采用活性炭和5A分子筛作为吸附剂,并以测得的原料气中各组分在两种吸附剂上的吸附数据为基础,进行了六塔快速变压吸附工艺的数值模拟与分析。在分析了塔内温度、压力和固相的浓度分布后,探究了进料流量、双层吸附剂高度比以及冲洗进料比三个操作参数对于快速变压吸附工艺性能的影响,结果表明：原料气组成为H₂/CH₄/CO/CO₂=76%/3.5%/0.5%/20%,吸附压力为22 bar（1 bar=10⁵ Pa）,解吸吹扫压力为1.0 bar,处理量为0.8875 mol·s^-1,吸附剂床层高度比为0.5∶0.5,冲洗进料比为22.37%时,可获得H₂纯度99.90%,回收率69.88%,此时H₂产量为0.4713 mol·s^-1。相比之下,氢气纯度为99.90%时,尽管PSA工艺回收率为83.40%,但处理量只有0.39 mol·s^-1,因此H₂产量仅为0.2472 mol·s^-1。     

氢气分离膜内嵌改进蒸汽活化转化丙烷脱氢过程模拟和经济分析

在蒸汽活化转化（STAR）工艺中,丙烷脱氢反应产物含有大量氢气、甲烷等不凝组分,传统的高压低温液化流程,操作压力达到3.30MPa,浅冷温度-24℃,深冷温度-78℃,不仅压缩能耗高,而且氢气副产品浓度低,无法直接在炼化过程中实现利用。对此,本文提出在浅冷之后嵌入氢气膜分离单元,采用Prism-Ⅱ膜脱除反应产物中大部分氢气后再进一步增压和深冷液化。采用HYSYS对改进工艺模拟优化后得出：浅冷操作压力2.40MPa、温度-24℃,深冷操作压力3.30MPa、温度-78℃,总压缩能耗降低16.1%,氢气纯度由82.8%提高到99.0%,回收率超过85%。以350kt/a STAR工艺为例进行改进工艺的技术经济分析,最优膜面积为2680m²,总压缩功耗由6850kW降低至5750kW,节约公用工程约5.72×10⁶CNY/a,设备折旧仅增加0.61×10⁶CNY/a,产出氢气约1.23×10⁸m³/a。综合考虑节能、新增设备折旧和氢气产出,年净收益增加8.7×10⁷CNY。结果表明,膜分离改进有效地提高了STAR工艺的能效和经济性。     

氨氮废水汽提精馏与MVR联用技术设计计算

针对氨氮含量为14 g/L、进料流量为100 m³/h、出水氨氮浓度<10 mg/L、回收浓氨水15%以上的体系进行了理论物料衡算，发现汽提精馏与MVR联用技术脱氨与直接蒸汽加热相比，吨废水处理的水蒸汽耗量降低了101.5 kg（不计首次开车时通入的蒸汽量）,塔釜废水减量119.8 kg,回收15%浓氨水增量18.3 kg;并计算获得压缩机实际功率W₀=2.10×10⁶ W。理论验证了汽提精馏与MVR联用技术节能降耗的可行性。     

臭氧/过硫酸氢钾体系降解酮洛芬的动力学研究

利用臭氧/过硫酸氢钾体系降解酮洛芬模拟废水,考察了不同反应温度、初始浓度、初始p H值下酮洛芬的降解动力学,并拟合表观动力学方程;采用竞争法,以硝基苯和苯甲酸为分子探针,测定酮洛芬与硫酸根自由基的二级反应速率常数。结果表明,不同实验条件下酮洛芬降解符合准一级动力学,通过对实验数据进行拟合得到表观动力学方程k=494296exp（-31494/RT） C₀^-0.3677[OH^-]^0.1478,酮洛芬与硫酸根自由基的二级反应速率常数为1.49×10⁹M^-1s^-1。     

化学链干重整联合制氢热力学分析及实验

提出了一种化学链甲烷干重整联合制氢工艺。该工艺由还原反应器、干重整反应器、蒸汽反应器和空气反应器组成，在实现制氢的同时获得可变H₂/CO比的合成气。借助ASPEN plus软件和小型流化床实验台，在等温条件下，温度900℃，采用Fe₂O₃/Al₂O₃载氧体，对该工艺进行热力学分析和实验验证。结果显示，当铁氧化物被还原至FeO/Fe时，干重整反应器内甲烷转化率可以达到98%，CO产率可以达到94%。干重整反应器中同时发生甲烷干重整和部分氧化反应，载氧体内部晶格氧可以有效降低积炭并提高合成气H₂/CO比。积炭发生于晶格氧消耗殆尽时。积炭进入蒸汽反应器，发生气化反应，降低氢气纯度。     

乏风瓦斯流向变换催化燃烧试验研究

为实现低浓度瓦斯气体的高转化率,满足实际工程低温排气的要求,设计制作一套新型流向变换蓄热催化燃烧反应器,并利用模拟气体进行催化燃烧实验研究。结果表明,气体流量为70 L·min^-1、燃烧反应温度控制在500 ℃和甲烷体积分数为0.2%时,甲烷催化燃烧转化率超过80%,出口气体温度低于60 ℃。该系统能满足工程低温排气要求。     

UV-LED/NaClO工艺降解水中邻苯基苯酚的活性组分贡献和影响因素

采用紫外发光二极管协同次氯酸钠(UV-LED/NaClO)工艺对水中邻苯基苯酚(OPP)去除进行研究,以硝基苯(NB)、苯甲酸(BA)和二甲氧基苯(DMOB)为探针物质,采用竞争动力学确定了UV-LED/NaClO工艺中HO·、Cl·和ClO·的稳态浓度及其与OPP的二级反应速率常数,研究OPP降解过程中不同组分的贡献,考察NaClO投加量和pH对OPP去除及不同组分贡献的影响。结果表明：UV-LED/NaClO可以有效降解OPP,其降解拟一级动力学常数为0.275 2 min^-1(拟合优度R²=0.993 4)。当NaClO投加量为3 mg·L^-1时,HO·、Cl·和ClO·稳态浓度分别为1.22×10^-13、1.08×10^-14和1.38×10^-12 mol·L^-1,其与OPP的二级反应速率常数分别为1.86×10⁹、1.33×10¹¹和2.18×10⁸ L·mol...     

甲烷化反应工艺流程和反应器模拟

通过分析绝热反应曲线和反应过程CO转化率曲线,设计可行的多级绝热固定床甲烷化工艺流程,得到了一个第一甲烷化反应器循环比为3.0,反应器个数为3的甲烷化反应系统。建立绝热固定床反应器的一维拟均相数学模型,在工业操作条件下,分析了该流程中3个甲烷化反应器内的温度和摩尔分数分布规律。在合成气的进料速度800 kmol/h,进料温度553 K,操作压力为3.0 MPa,氢碳物质的量比约为3.0,循环比为3.0的条件下,模拟结果表明:物料在3个反应器出口的温度分别为879,725,611 K;甲烷干基摩尔分数分别为53.48%,79.24%和95.49%;CO在3个反应器出口的转化率分别为82.18%,99.41%和100%。第3反应器出口CH4干基摩尔分数为95.49%,满足了工业生产要求。     

H_2促进C_3H_6在Ag/Al_2O_3催化剂上SCR-NO的研究

少量H_2可以增强丙烯在Ag/Al_2O_3催化剂上选择性还原NO的活性,降低NO的起燃温度(<100℃),在2个温度区间内NO转化率比较高:第1个是低温区间80¹80℃,第2个是250180℃,第2个是250⁵00℃,在这两个温度区间内NO的转化率没有太大变化,在中间温度区间内比较低,低温区间NO转化率较高是由于H_2的还原作用,当温度高于180℃时C_3H_6起主要作用。N_2和NO_2是主要的竞争产物低温时有NO_2形成,当温度在140℃左右和高于380℃的时候对N_2的选择性非常高,在200℃和260℃时NO_2的浓度77×10500℃,在这两个温度区间内NO的转化率没有太大变化,在中间温度区间内比较低,低温区间NO转化率较高是由于H_2的还原作用,当温度高于180℃时C_3H_6起主要作用。N_2和NO_2是主要的竞争产物低温时有NO_2形成,当温度在140℃左右和高于380℃的时候对N_2的选择性非常高,在200℃和260℃时NO_2的浓度77×10^(-6)(-6)⁸3×1083×10^(-6)占主要产物,165(-6)占主要产物,165⁵00℃时仅仅检测到N_2O_2×10500℃时仅仅检测到N_2O_2×10^(-6),对H_2-C_3H_6-SCR的反应体系,500℃时比较高的空速条件下会生成48×10(-6),对H_2-C_3H_6-SCR的反应体系,500℃时比较高的空速条件下会生成48×10^(-6)NH_3并增加了CO/CO_2比值。氧气和催化剂表面NO_2等中间体与还原剂之间存在着竞争反应,但是仍能被还原成N_2,这些中间产物在低温时容易被H_2还原而在高于180℃时易被C_3H_6还原。通过XPS分析可以发现,部分活性组分Ag在载体Al_2O_3上即使在低温条件下也非常不稳定,由于不同价态银物种相互作用使催化剂在不同温度区间内活性不同选择性也有很大差别,在C_3H_6-SCR反应之后Ag(-6)NH_3并增加了CO/CO_2比值。氧气和催化剂表面NO_2等中间体与还原剂之间存在着竞争反应,但是仍能被还原成N_2,这些中间产物在低温时容易被H_2还原而在高于180℃时易被C_3H_6还原。通过XPS分析可以发现,部分活性组分Ag在载体Al_2O_3上即使在低温条件下也非常不稳定,由于不同价态银物种相互作用使催化剂在不同温度区间内活性不同选择性也有很大差别,在C_3H_6-SCR反应之后Ag⁺和Ag_n+和Ag_n^(δ+)物种随之出现,当在反应气中通入H_2以后金属纳米Ag单质也会生成。XRD结果也同样表明,在H_2-C_3H_6-SCR反应后有大于5 nm的Ag纳米粒子形成。     

基于ASPEN PLUS软件的甲烷化工艺模型

利用ASPEN PLUS对煤制天然气的甲烷化工艺进行了流程模拟。模型模拟得到了替代天然气成分、反应器出口温度、循环比、分流率,揭示了循环比和分流率对反应器出口温度的影响。通过该模型,能够为工艺方案比选、优化设计提供模拟和预测。     

鲁奇甲醇生产装置的数学模拟和工况分析——(Ⅱ)鲁奇管式变换炉

建立了鲁奇甲醇装置中管式变换炉催化床的一维数学模型,模拟计算了变换炉催化床气体浓度、床层温度、冷管内气体温度分布,讨论了不同操作条件对变换率及床层出口温度的影响。     

生物质气化模型的流程模拟

生物质能是一种重要的可再生能源。通过Aspen Plus软件平台,建立生物质气化反应器模型,对生物质气化过程进行模拟计算,探讨了不同反应条件,包括气化温度、压力以及水蒸气与生物质质量配比（S/B）对气化产物成分的影响。计算结果表明,采用生物质蒸汽气化技术可获得体积分数为60%以上的富氢燃料气,且增大水蒸气与生物质质量配比有利于氢气产率的提高。     

Analysis and optimization of two-column cryogenic process for argon recovery from hydrogen-depleted ammonia purge gas

Traditionally, high-purity argon recovery from air is considerably difficult owing to the boiling point of argon close to that of oxygen. Recently with the increasing demands for argon, another attractive source of ammonia purge gas has been paid more attention. In this paper with an objective of minimizing energy consumption per argon product, the two-column process for recovering argon from hydrogen-depleted ammonia purge gas is analyzed and optimized in detail on the ASPEN PLUS platform. Firstly, the model of two-column process is set up using the standard unit operation blocks and PENG-ROB property method of ASPEN PLUS, in which validation of PENG-ROB property method is carried out by comparison with a total 623 experimental data from three aspects: vapor-liquid equilibrium, liquid phase density, and enthalpy. It is followed by the thermodynamic and simulation and sensitivity analysis, which on the one hand can reduce the number of decision variables related to optimization problem, and on the other hand can obtain reasonable parameter specification, variables initial values and ranges, thus effectively ensuring the later optimization algorithm converges quickly and accurately. Finally the built-in sequential quadratic programming (SQP) solver of ASPEN PLUS is adopted to solve the minimum energy consumption optimization problem of two-column process. On the processor of 2.66 GHz Intel(R) Core (TM)2 Duo CPU with 4 GB RAM, the whole optimization only takes CPU times 10 s or so to accomplish. The optimal results show that thermal state of feed to demethanizer is a very efficient and valuable means to reduce system energy consumption which at T_C05 = 103 K is only 87.4% of that at T_C05 = 109 K where T_C05 is the temperature of feed to demethanizer directly reflecting its thermal state. The condensing pressure of hydrogen-depleted ammonia purge gas also plays a vital role in reducing system energy consumption which is less at higher condensing pressure, whereas it almost has no influence on the yield and purity of argon recovery. The optimal operating pressure of flash separator used to remove the residual hydrogen in the feed hydrogen-depleted ammonia purge gas is 0.4-0.6 MPa (A); the most economical reflux ratio of argon distillation column is 1.15, and that of demethanizer varies from 0.33 to 0.45 depending on thermal state of feed to demethanizer.     

Biomass to hydrogen via catalytic steam reforming of bio-oil over Ni-supported alumina catalysts

Production of hydrogen (H₂) from catalytic steam reforming of bio-oil was investigated in a fixed bed tubular flow reactor over nickel/alumina (Ni/Al₂O₃) supported catalysts at different conditions. The features of the steam reforming of bio-oil, including the effects of metal content, reaction temperature, W_bHSV (defined as the mass flow rate of bio-oil per mass of catalyst) and S/C ratio (the molar ratio of steam to carbon fed) on the hydrogen yield were investigated. Carbon conversion (moles of carbon in the outlet gases to moles of the carbon feed) was also studied, and the outlet gas distributions were obtained. It was revealed that the Al₂O₃ with 14.1% Ni content gave the highest yield of hydrogen (73%) among the catalysts tested, and the best carbon conversion was 79% under the steam reforming conditions of S/C = 5, W_bHSV = 13 1/h and temperature = 950 °C. The H₂ yield increased with increasing temperature and decreasing W_bHSV; whereas the effect of the S/C ratio was less pronounced. In the S/C ratio range of 1 to 2, the hydrogen yield was slightly increased, but when the S/C ratio was increased further, it did not have an effect on the H₂ production yield.     

粗合成气甲烷含量与水煤浆气化温度关系初探

用ＡＳＰＥＮＰＬＵＳ对高压水煤浆气化过程做了模拟计算，得到不同气化温度下的粗合成气中甲烷含量，为实际生产中间接预测气化炉温度提供参考。     

Kinetics of steam reforming over a Ni/alumina catalyst

Steam reforming of methane over a commercially available, nickel/alumina catalyst was experimentally studied. The reactor employed for the study was made of 7 mm i.d. quartz tube and catalyst particles were 0.84-1 mm in size. The amount of catalyst charge in the reactor was around 0.3 gram. Experiments were carried out varying the steam to methane ratio in the feed gas from 1 to 10 and reaction temperature from 823 to 1073 K. Nitrogen gas was used to control partial pressure of methane and steam. Using Marquardt method reaction rate derived from the experiments was fitted to $$reaction rate = 1,527 exp( - 14,820/RT) P^{1.014} _{CH_4 } P^{ - 0.9577} _{H_2 0} $$ Thus reaction order was close to one for methane and close to minus one for steam, respectively.     

乙苯蒸发器乙苯热进料投用效果分析

介绍了E-304乙苯蒸发器原进料条件下高能耗的原因分析,针对存在问题提出了投用热乙苯进料线的优化方案。乙苯蒸发器乙苯热进料线投用后,在同样的进料量,脱氢水比和反应压力情况下,0.35 MPaG汽化蒸汽用量节省了0.6 t/h,年可节省蒸汽约0.50万t,1.0 MPaG蒸汽年消耗量减少了168 t,F-301过热蒸汽加热炉的燃料气用量节省0.02 t/h,年可节省198.33 t,节能降耗效果非常显著。     

Mathematical Modeling and Optimization of Combined Steam and Dry Reforming of Methane Process in Catalytic Fluidized Bed Membrane Reactor

Mathematical modeling of the methane-combined reforming process (steam methane reforming–dry reforming methane) was performed in a fluidized bed membrane reactor. The model characterizes multiple phases and regions considering low-density phase, high-density phase, membrane, and free board regions that allow study of reactor performance. It is demonstrated that the combined effect of membrane and reaction coupling provides opportunities to overcome equilibrium limits and helps to achieve higher conversion. Additionally, the influence of key parameters on reactor performance including reactor temperature, reactor pressure, steam to methane feed ratio (S/C), and carbon dioxide to methane feed ratio (CO₂/C) were investigated in the multi-objective genetic algorithm to find the optimal operating conditions. Finally, the process of steam reforming was simulated in selected optimal conditions and the results are compared to those of the combined reforming process. Comparison reveals the superiority of the combined reforming process in terms of methane conversion, catalyst activity, and outlet H₂/CO ratio in the syngas product in being close to unity.     

Synthesis gas production using steam hydrogasification and steam reforming

Experimental work has been carried out on the mixed reforming reaction, i.e., simultaneous steam and CO₂ reforming of methane under a wide range of feed compositions and four different reaction temperatures from 700 °C to 850 °C using a commercial steam reforming catalyst. The experiments were conducted for a CO₂/CH₄ ratio from 0 to 2 and a steam to methane ratio from 3 to 5. The effect of CO₂/CH₄ ratio on the exit H₂/CO ratio and the conversions of the reactants indicate that the dry reforming reaction is dominant under increased carbon dioxide in the feed. Steam reforming of typical steam hydrogasification product gas consisting of CO, H₂ and CO₂ in addition to steam and methane has also been investigated. The H₂/CO ratio of the product synthesis gas varies from 4.3 to 3.7 and from 4.8 to 4.1 depending on the feed composition and reaction temperature. The CO/CO₂ ratios of the synthesis gas varied from 1.9 to 2.9 and 2.0 to 3.3. The results are compared with simulation results obtained through the Aspen Plus process simulation tool. The results demonstrate that a coupled steam hydrogasification and reforming process can generate a synthesis gas with a flexible H₂/CO ratio from carbon-containing feedstocks.