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31.
A methodology for hazard investigation based on the integration of a mathematical model approach into hazard and operability
analysis is presented. This approach is based on mathematical modelling of a process unit where both steady-state analysis,
including analysis of the steady states multiplicity and stability, and dynamic simulation are used. The dynamic simulation
serves for the investigation of consequences of failures of the main controlled parameters, i.e. inlet temperature, feed temperature
and feed composition. This simulation is also very useful for the determination of the influence of failure duration on the
reactor behaviour. On the other hand, the steady state simulation can predict the reactor behaviour in a wide range of failure
magnitude and determine the parametric zones, where shifting from one steady state to another one may occur. A fixed bed reactor
for methyl tertiary-butyl ether synthesis was chosen to identify potential hazard and operational problems of a real process.
Presented at the 34th International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 21–25 May
2007. 相似文献
32.
KINETICS OF SULFUR POISONING IN A FIXED BED FOR F-T SYNTHESIS OVER COMMERCIAL Fe-Cu-KCATALYST 下载免费PDF全文
IntroductionSulfurpoisoningofanironcatal}'stisoneofthemostseriousdcactivationproblemsincomn'crcialproductionofsubstitutingnaturalgasforcoalreportedb}'Bartholomc\\ofal.II1andAndersonofal.12I.Thecommercialco-precipitatedFo-Cu-Kcatal\'stpreparedb}'Instituteo… 相似文献
33.
LIU Zhao-Tie ZHOU Jing-LaiZHANG Zhi-Xin ZHANG Bi-JiangInstitute of Coal Chemistry Academia Sinica To whom correspondence should be addressed. 《天然气化学杂志》1995,(1)
In part I, we investigated some behavior of copper- potassium promoted iron catalyst for the synthesis of hydrocarbon from hydrogen and carbon monoxide, with particular attention to the influence of reaction temperature, operating pressure, space velocity, H2/CO ratio in feed gas and particle size of catalyst on CO conversion. In this part, more attention was paid to the whole product distribution, such as wax, oil, oxygenate and the composition of oil and oxygenate. It is seen that the operating conditions greatly affect the whole product distribution and its composition. 相似文献
34.
固定床反应器——科学、技术和艺术 总被引:1,自引:0,他引:1
本文是关于固定床反应器现状及可能发展的综述。作为一种传统的反应器,固定床反应器在模型理论上已相当完善。但是由于模型和模型参数的不确定性,要通过模型化来实现优化操作几乎是不可能的。因而从科学方法的观点提出了基于状态估计和参数估计的动态优化方法。固定床反应器的一种可能发展趋势是与有关的一种(或几种)技术结合,最有可能的是与膜技术结合或与催化剂设计技术结合,实现反应一分离的综合日标。最后,本文叙述了组合已有的化学工程的原理和技术,使固定床反应器在降低能耗、提高收率等方面取得的进展。 相似文献
35.
在三相淤浆床-固定床反应装置中,研究含氮合成气直接合成二甲醚。使用双功能混合催化剂,粒度为0.15 mm~0.18 mm。在220 ℃~260 ℃、3.0 MPa~7.0 MPa、空速1 000 mL·g-1·h-1时考察了温度、压力及两种反应器中催化剂的装填比例对CO转化率及二甲醚选择性的影响。结果表明,一氧化碳转化率随反应压力的增加而提高,随着温度升高二甲醚的选择性变化不大,CO转化率的升高较明显,因此在催化剂活性适宜的温度范围内,该反应装置可以采用较高的反应温度。当260 ℃、7.0 MPa、三相床与固定床中催化剂比例为1∶1时,CO的转化率可达84.5%,二甲醚的选择性为78.7%。淤浆床-固定床反应装置具有操作稳定性好、CO转化率高的优点。催化剂在该装置中反应370 h活性没有明显下降。 相似文献
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Bruno R Figueiredo Simão P Cardoso Inês Portugal João Rocha 《Separation & Purification Reviews》2018,47(4):306-336
Ion exchange is a proven process for radioactive wastewater decontamination, where inorganic sorbents are ideal due to their thermal, chemical and radiation stability. This review focuses on the removal of Cs+ by inorganic exchangers, viz. zeolites, titanosilicates, hexacyanoferrates metal oxides and hydrous metal oxides, bentonite/clays and the key family of ammonium phosphomolybdates (AMPs). The design of new selective composites is also addressed focusing on those based on AMPs, hexacyanoferrates and titanosilicates/zeolites. Future inorganic Cs+ exchangers will encompass promising solids, like lanthanide silicates, sodium titanates and metal sulfides. The sensing ability derived from the photoluminescence properties of lanthanide silicates and the efficiency of layered gallium-antimony-sulfide materials in acidic and basic solutions disclose considerable potential for real applications. The ion exchange systems are discussed in terms of sorbent capacity and selectivity (with competitors), pH, temperature and solution salinity. The microscopic features of the exchangers and the associated mechanisms (e.g., pore size, counterions radii, dehydration energy of the ions, coordination environments in the solid exchanger, and site accessibility) are always used for interpreting the ion exchange behavior. On the whole, more than 250 publications were reviewed and a large compilation of data is provided in Supplemental Material. 相似文献
39.
氧气对褐煤水蒸气气化半焦的活化及机理 《燃料化学学报》2018,46(11):1288-1297
以胜利褐煤为原料,利用一段流化床/固定床石英反应器,进行N_2/O_2/H_2O/H_2O+O_2气氛的褐煤热解/气化实验。采用BET、Raman、FT-IR、微波消解ICP-AES、TGA等技术表征半焦。研究氧气添加对气化反应以及半焦结构和反应性的影响,解析了氧气对气化半焦的活化机理。结果表明,氧气添加可以改变半焦结构,活化半焦,从而促进转化率、H_2产率和CO_2产率的提高。氧气对气化半焦的活化作用主要包括两个方面,一是芳核与氧气发生氧化分解反应,破坏了芳环大π键,形成了新的官能团,从而促进了反应(C+H_2O→H_2+CO)的发生;二是随反应的进行,芳香大环(≥6)结构解聚为芳香小环(3-5)结构,同时氧原子进入芳核,形成缺陷位C-O-C,从而导致半焦微晶结构的缺陷程度提高、缩聚程度降低,进而导致半焦反应性和表面吸附作用提高,促进反应(CO+H_2O→H_2+CO_2)的发生。 相似文献
40.
Gy?rgy Sz?llsi Beáta Hermán Ferenc Fül?p and Mihály Bartók 《Reaction Kinetics and Catalysis Letters》2006,88(2):391-398
Summary The Pt-alumina-CD catalyzed enantioselective hydrogenations of ethylpyruvate (EP), ketopantolactone (KPL) and methyl benzoylformate
(MBF) have been studied at first in an H-Cube flow hydrogenator in toluene and toluene + acetic acid. Based on the experience
of previous studies carried out in batch-reactor and continuous flow systems, some parameters were kept constant (amount of
catalyst, 380 mg; substrate concentration, 0.18 mol/L; temperature, 283 K), whereas others, namely chiral modifier (CD) concentration,
hydrogen pressure and total liquid flow (TLF: substrate + modifier + solvent) were varied. In the course of enantioselective
hydrogenation (R)-products were formed in excess: in the case of EP, KPL, MBF: 90, 60, 80 % enantioselectivities were obtained. 相似文献