壳牌煤气化中的平衡操作

为了保障装置的安全、稳定、长周期运行,通过在实际操作中对工况的调节与对系统的优化,讨论了阀门等设备故障、上下游系统波动等对气化炉压力、汽包压力、氮气/二氧化碳管网压力、煤粉管线流量平衡的影响,分析了气化炉压力、汽包压力、氮气/二氧化碳管网压力、煤粉管线流量失衡对生产的危害,并总结出保持气化炉压力、汽包压力、氮气/二氧化碳管网压力、煤粉管线流量平衡的方法,指出保持这些关键参数平衡对壳牌煤气化装置良好运行的重要意义。

Industrial catalysis:Strategies to enhance selectivity

Precise control of catalytic selectivity is a key concept of green chemistry,and also an important driving force for the sustainable development of catalytic industry.Selectivity not only determines the atomic economy of the catalytic process,but also affects the energy consumption of subsequent separation process.The objective of this review is to illustrate successful catalyst design strategies to enhance selectivity,by using several important catalytic cases of petroleum refining and petrochemicals.These industrial applications and cutting-edge research cases mainly use the strategies of coupling,decoupling or confinement of adsorption sites and active sites to tune the diffusion barrier and activation energy barrier in different routes,so as to improve the selectivity of catalyst.Based on the preliminary understanding of selectivity improvement,it is necessary to systematically investigate the selective catalytic processes using combination of multiple strategies,thereby realizing the design of highly selective catalyst over reasonable time scales and space scales.

Analysis and Comparison of the Alpha Functions of SRK Equation of State

Alpha functions of Soave-Redlich-Kwong （SRK） equation of state proposed by Soave, Twu, and Luo were different in mathematic tendency. They were compared in modeling methane-alkanes equilibria with van der Waals mixing rule and Modified Huron-Vidal （MHV1） mixing rule, respectively. Results showed that Luo＇s alpha function was a little more accurate than Soave＇s, and Twu＇s alpha function lacked accuracy in modeling methane-alkanes equilibrium. SRK equation of state was expanded as virial form, and then the equivalent terms were contrasted with terms of virial equation of state. Results showed that Soave＇s and Luo＇s alpha functions matched the tendency of virial coefficient better than Twu＇s, and Luo＇s alpha function matched better than Soave＇s in wide temperature range, which sustained the conclusions of phase equilibria calculation. Luo＇s alpha function keeps decreasing when Tr〉 1 and becomes negative at sufficient high temperature, thus the conventional cubic equation of state expressed pressure as the sum of repulsion pressure PR （〉0）, and attraction pressure PA （〈0） could be improved to be the sum of hard-sphere repulsion pressure PH （〉0） and intermolecular force pressure P1 （P1〈0 at low temperature and p1〉0 at sufficient high temperature）.

Preparation of Alumina Abrasion-Resistant Ceramic Grinding Ball with Spent FCC Equilibrium Catalyst

The chemical composition, structure and thermal stability of the spent FCC equilibrium catalyst from an oil refinery were characterized by XRD, FT-IR, DTA-TG, BET, complete chemical analysis, SEM, and XRF. The spent FCC equilibrium catalyst, clay, barium carbonate, and talc were used as the main raw materials to prepare the alumina abrasion-resistant ceramic balls to be used in the powder grinding mill for manufacture of architecture tiles. The results showed that after proper formulation study, the spent FCC equilibrium catalyst could replace industrial alumina to prepare high performance grinding balls. Meanwhile, the various performance indices of the grinding ball could meet the quality standard for similar products, and additionally, the energy saving effect was achieved in the operation of the grinding section, resulting in a successful comprehensive utilization of solid wastes.

Optimization of assembly line balancing using genetic algorithm

In a manufacturing industry, mixed model assembly line(MMAL) is preferred in order to meet the variety in product demand. MMAL balancing helps in assembling products with similar characteristics in a random fashion. The objective of this work aims in reducing the number of workstations, work load index between stations and within each station. As manual contribution of workers in final assembly line is more, ergonomics is taken as an additional objective function. Ergonomic risk level of a workstation is evaluated using a parameter called accumulated risk posture(ARP), which is calculated using rapid upper limb assessment(RULA) check sheet. This work is based on the case study of an MMAL problem in Rane(Madras) Ltd.(India), in which a problem based genetic algorithm(GA) has been proposed to minimize the mentioned objectives. The working of the genetic operators such as selection, crossover and mutation has been modified with respect to the addressed MMAL problem. The results show that there is a significant impact over productivity and the process time of the final assembled product, i.e., the rate of production is increased by 39.5% and the assembly time for one particular model is reduced to 13 min from existing 18 min. Also, the space required using the proposed assembly line is only 200 m2 against existing 350 m2. Further, the algorithm helps in reducing workers fatigue(i.e., ergonomic friendly).

The Modeling and Simulation of Reactive Distillation for the Esterification Process

In this paper,a generalized model of the reactive distillation processes was developed via rate-based approach. The homotopy-continuation method was employed to solve the complicated nonlinear model equations efficiently. The simulation on the reactive distillation processes was carried out with the profiles of stage temperature,composition and flow rate for both vapor and liquid phases obtained. Based on careful analysis of the simulation results, the pitfalls in experimental design were detected. Finally, a software package for the simulation of reactive distillation processes was developed.

Selective extraction of In(Ⅲ),Ga(Ⅲ) and Zn(Ⅱ) using a novel extractant with phenylphosphinic acid

A new extractant, [N,N-di（2-ethylhexyl）aminolmethylphenylphosphinic acid （DEAPP）, was synthesized to de- velop the mutual separation techniques of In（Ⅲ）, Ga（Ⅲ） and Zn（Ⅱ）. The extraction selectivity for In（Ⅲ）, Ga（Ⅲ） and Zn（Ⅱ） with DEAPP was higher than that of the commercial phosphorus acid extractants such as D2EHPA and PC-88A. The extraction selectivity for metal ions in 1 mob L 1 aqueous ammonium nitrate solution with DEAPP was in the following order： In（Ⅲ） 〉 Ga（Ⅲ） 〉 Zn（Ⅱ）. These selective extraction behaviors indicate that the amino moiety of DEAPP plays an important role in the mutual separation of ln（Ⅲ）, Ga（Ⅲ） and Zn（ll）. The extraction equilibria of In（Ⅲ）, Ga（Ⅲ） and Zn（Ⅱ） with DEAPP （ = HR） were expressed by the following reactions： In3＋ ＋ 2（HR）2 InR3（HR） ＋ 3H＋, Ga3＋ ＋ 1.5（HR）2 ＋ N- = GaR2（HR）（NO3） ＋ 2H＋, and Zn2＋ 4- 2（HR）2 ZnR2 （HR） 2 determined 4- 2H＋. The extraction equilibrium constants of In（Ⅲ）, Ga（Ⅲ） and Zn（Ⅱ） with DEAPP were to be Kex, M = 1.7 × 104 [dm3.mol 1], 4.17 [（dm3.mol-1）s], and 1.55 × 10 2 [-], respectively.

Effect of Ultrasound on Desorption Equilibrium

Effects of ultrasound on intensification of separation process were investigated through the experiment of desorption equilibrium behavior. Tri-butyl phosphate (TBP) on NKA-II resin and phenol on a solvent impregnated resin, CL-TBP resin, were used for desorption processes. The desorption rate was measured with and without ultrasound. Desorption equilibrium was studied under various ultrasonic power densities or thermal infusion. Results showed that the desorption rate with ultrasound was much higher than that with normal thermal infusion. Both ultrasound and thermal infusion broke the desorption equilibrium existed at room temperature. However, after the systems were cooled down, the amount of solute desorbed in the liquid phase in the presence of ultrasound was much higher than that at the temperature corresponding to the same ultrasound power. It is proved that the initial desorption equilibrium was broken as a result of the spot energy effect of ultrasound.

Craftsmanship as the Model of a New Cultural Way

In this essay the idea is put forward that rethinking doing is the task that human sciences will need to undertake in the twenty-first century because the dichotomy do/think is one of the most deceptive and dangerous that the Western furor dividendi has ever formulated. Likewise, this is the time to re-do thinking： Both activities, divided from each other, are today quantitatively efficient, but incapable of making sense of themselves, of their own proceeding and of the world where they operate. Similarly incapable are the people who perform them and suffer cruelly from this defeat. It would take a rehabilitated subject, restored to an active role as interpreter and creator of culture, to remedy these shortcomings, reintegrating the spheres in a tensile equilibrium rich in novelty and significance. To this end, in an interdisciplinary perspective, insights by Dumont, Simmel, and Damasio are discussed and connected to Sennett＇s crucial intuition of the need for a new craftsmanship. This becomes the model of a foundational cultural act, in which a complex vision of culture joins a subjectivity that is at the same time a dynamic balance between rational and emotional components and a process where body and soul are inextricably entwined.

Polycyclic aromatic hydrocarbons in the centralized wastewater treatment plant of a chemical industry zone:Removal,mass balance and source analysis

Increased attention has been given to the fate of pollutants such as polycyclic aromatic hydrocarbons (PAHs) introduced to the wastewater treatment plants.Dissolved and adsorbed PAHs were detected in the centralized wastewater treatment plant of a chemical industry zone in Zhejiang Province,China.The most abundant PAHs were the low molecular weight PAHs (e.g.,Acy,Ace,Flu and Phe),accounting for more than 80% of the total 16 PAHs in each treatment stage.Phase partitioning suggested that the removal of PAHs in every treatment stage was influenced greater by the sorption of particles or microorganisms.The removal efficiencies of individual PAHs ranged between 4% and 87% in the primary sedimentation stage,between 1% and 42% in anaerobic hydrolysis stage,between <1% and 70% in aerobic bio-process stage,between 1.5% and 80% in high-density clarifier stage,and between 44% and 97% in the whole treatment process.Mass balance calculations in primary stage showed significant losses for low molecular weight PAHs and relatively good agreements for high molecular weight PAHs as well as in anaerobic hydrolysis,high-density clarifier stage and sludge stream for most PAHs.Great gains of 60%-150% were obtained for high molecular weight PAHs in aerobic bio-process stage due to biosorption and bioaccumulation.Our investigations found that PAHs entering the wastewater treatment plant (WWTP) could be derived from the dyeing chemical processes as the byproducts,and the contribution supported by the largest dyeing chemical group was up to 48%.