煤化工装置中硫回收单元的模拟设计

采用Sulsim软件,对煤化工装置中硫回收单元进行流程模拟设计。采用不同浓度的氧气与同一原料酸性气发生燃烧反应,讨论了氧气浓度对燃烧反应的影响,分析了采用Sulsim软件中不同的燃烧反应经验模式设计对模拟结果的影响。模拟结果表明,使用纯氧可大幅度提高装置处理能力,且在Sulsim软件模拟中,炉膛燃烧反应模式选用富氧燃烧模式更为可靠。模拟结果与国内外研究资料及实际工厂运行情况吻合,并分析了该模拟结果产生的原因及其对于工业设计的意义。     

Process development of treatment plants for dyeing wastewater

A three‐step methodology that integrates experiments, modeling and synthesis has been developed for the systematic development of a plant for treating dyeing wastewater for discharge and/or reuse. First, wastewater characteristics, discharge water standards, and reuse water quality specifications, etc. are collected as input information. Heuristics developed in our industrial practice and gleaned from the literature are used to guide the designer to come up with preliminary flow sheet alternatives. Then, bench‐scale experiments and pilot plant tests for the relevant unit operations are performed. A computer code accepts the bench‐scale and pilot plant experimental data for regression of model parameters and determines the superior process configuration and equipment operating conditions through sensitivity analysis. The workflow among various stakeholders to reach the final design is presented. Possible extension of the methodology to other industrial wastewater treatment plants is discussed. © 2011 American Institute of Chemical Engineers AIChE J, 2012     

A bench-scale method for evaluating the processing characteristics of oilseeds for filtration-extraction

Summary A simple laboratory testing apparatus and its use have been described. With relatively few pounds of material it is possible to evaluate many preparation and filtration variables and to predict with a fair degree of accuracy the behavior of a continuous horizontal vacuum filter. It is felt that such a unit will be invaluable for use in commercial plants, especially during the start-up operations of a new plant. The bench-scale unit should also find application in connection with other processes employing the unit operations of extraction and filtration. Presented before the Fall Meeting of the American Oil Chemists' Society, Nov. 2–4, 1953, Chicago, Ill. One of the laboratories of the Southern Utilization Research Branch, Agricultural Research Service, U. S. Department of Agriculture.     

Entwicklung petrochemischer Verfahren vom Laborversuch zur kommerziellen Anlage

Development of a petrochemical process from laboratory scale tests to a commercial plant. A plant producing TAME (tertiary amyl methyl ether) and isoamylene serves as an example illustrating the development of a petrochemical process from laboratory scale tests to a commercial size plant. TAME is an anti-knock compound used in unleaded gasoline, and isoamylene is a multi-purpose specialty chemical. In an introduction, the laboratory and pilot plants at EC Erdoelchemie GmbH in Cologne, Germany are presented. Subsequently the main process engineering developments made through experience gained with a semicommercial demonstration plant are discussed. These include optimization of the reactors, design of a methanol extraction unit, and the separation of TAME and high purity isoamylene in specially designed distillation towers. The high degree of coordination during the experimental testing phase to match the requirements of the basic and detail engineering allowed the commercial plant to be started up without expensive modifications within 4 years. The resulting savings overcompensate the costs of the semicommercial plant.     

Modelling batch bioreactions with continuous process simulators

Process models are increasingly becoming necessary for process understanding and optimizing. However, in the field of bioprocessing, modelling using a generic process simulator suffers from shortcomings given that many simulators cannot model batch mode bioreactors with varying reaction rates based on microbial metabolism. Bioprocesses, mostly batch, are difficult to model because most of the available unit operations in process simulators operate continuously. Our aim is to provide a general simulation platform to model these batch bioprocesses in commercial process simulators and explain how to transform batch processes with varying reaction rate into continuous unit operations for simulation purposes. Two typical fermentation processes, lactose fermentation and glucose/xylose co-fermentation, were simulated in steady state as case studies. The results are discussed as examples using the proposed approach. The potential of how to extend the simulation platform is also explained in detail.     

Removal of phosphorus and iron by commercial degumming of soybean oil

Samples of crude and water-degummed soybean oils were obtained from five commercial processors. period of at least 2 weeks between samples. The crude and degummed oils were analyzed for iron and phosphorus content. Phosphorus removal within each processing plant was consistent, but between plants removal varied from a low of 79% to a high of 95%. Removal of iron compounds during commercial degumming varied from a low of 14% to a high of 57%. Significance of these results in steam-refining operations are discussed. Presented in part at the AOCS meeting, New York, May 1977.     

煤焦油蒸馏工艺的选择

论述了国内外焦油蒸馏工艺的流程和特点,对新开发的焦油蒸馏工艺流程和特点进行了说明。通过比较,显示了新工艺的优越性,单套焦油处理能力可以达到50万t/a,实现了大型化和节能降耗,具有推广价值。     

Methyl esters directly from acidulated cottonseed soapstock. Preliminary cost study

A product containing from 80 to 95% of the methyl esters of cottonseed, soybean, and corn oil is produced commercially in the United States directly from the respective acidulated soapstocks of these oils, using a process developed at the Southern Utilization Research and Development Division. The product is marketed as a high-energy additive for poultry and livestock feed, and its ready acceptance indicates that it has nutritional and handling advantages over other by-product fats for this purpose, which, in 1958, represented a ready and expanding market for almost 600 million pounds of animal and vegetable fats and oils. A flow sheet for the process is given, and hypothetical plants with capacities of 15,000 and 60,000 lbs. of acidulated foots per 24 hrs. are described for the continuous production of up to 21 million pounds of methylated foots product annually. The lowest manufacturing costs are realized for each plant when operating 24 hrs. a day, 250 days annually, averaging five days per week. For these optimum operations the estimated capital investment for the small plant is $223,000, and for the large plant $410,000. Manufacturing costs range from a high of 11.2￠ per pound of product at an annual production of 11/4 million pounds to 6.5￠ at an annual production of 15.3 million pounds. The cost of the raw materials, although only 3.4￠ per pound of product and chiefly the cost of foots, is the largest single item of unit cost in producing methyl esters; and, for the higher productions covered by this study, raw material costs account for more than one-half of total unit manufacturing cost. Surplus cottonseed foots can be economically converted into a low-cost feed additive with improved nutritional and handling properties. The process is already a commercial success. Presented at the 51st Annual Meeting of the American Oil Chemists' Society, Dallas, Tex., April 4–6, 1960. Development Division, Agricultural Research Service, U. S. Department of Agriculture.     

间歇冶炼工艺烟气制酸装置的设计

对间歇冶炼工艺烟气制酸装置的设计和操作进行了论述。为解决气体流量和SO_2浓度的波动问题,确保硫酸装置稳定运行,提出了各种解决方案,其中包括增设焚硫炉或预干燥塔、注入液体SO_2、采用一转一吸装置加尾气洗涤塔等。     

振荡流发生装置应用研究进展

振荡流反应器是一种新型的化工设备。由于其独特的流动特点,能够强化许多化工过程,在化工生产中具有广泛的应用前景。文章介绍了振荡流反应器在设备结构、流场特点及停留时间特性等方面的基础研究以及它在发酵、生物反应器、絮凝、颗粒悬浮领域的应用状况。     

Pilot-plant fractionation of cottonseed. III. Process development of differential settling

Chemical engineering data are presented to show the pilotplant process development of cottonseed fractionation employing the differential settling principle. The purpose of the process is to produce a cottonseed meal fraction essentially free of pigment glands and hulls, and a second fraction in which the pigment glands are concentrated sufficiently to serve as a raw material if pharmaceutical or other industrial use is developed for the glands or the pigments. The non-lipids fraction will make available a meal of high nutritive value and a source of industrial protein. Unit operations involved, including machinery and other equipment required, and proposed flow diagrams for commercial application are discussed. In brief the unit operations are as follows: material preparation; disintegration for proper size reduction of cottonseed flakes (either defatted or undefatted) in solvent slurries; separation by tank differential settling or by centrifugal differential settling at 62 times gravity; meal recovery to recover separated fractions by either centrifuging at 1450 times gravity or by pressure filtration; desolventization of solvent-damp meal; and oil and solvent recovery. Report of a study made under the Research and Marketing Act of 1946. Presented at the apring meeting of the American Oil Chemists' Society, held in New Orleans, La., May 1949. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research administration, U. S. Department of Agriculture.     

A consolidated flow regime map of upward gas fluidization

A new flow regime map, resulting from more fundamental studies on the hydrodynamics and new flow regimes, is proposed in response to more practical reclassifications of the existing regimes with the development of upward gas-solids fluidization systems. The previously reported flow regime maps and flow structures of some widely used fluidized beds are carefully examined. To better reflect the industrial applications, the fast fluidization regime is reclassified as high-density and low-density circulating fluidization regimes. A consolidated flow regime map is then proposed where the flow regimes of upward fluidization expand to include new types of fluidized beds such as circulating turbulent fluidized bed and high-density circulating fluidized bed. The proposed flow regime map consists of six flow regimes: bubbling, turbulent, circulating turbulent, high-density circulating and low-density circulating fluidization, and pneumatic transport. The transitions between the regimes are discussed with new correlations proposed for fluid catalytic cracking type particles. Analysis on the dominating phase in the different types of fluidized beds reveals the dynamic changeover from solids phase continuous in conventional low-velocity batch/“fixed” fluidization operations to gas phase continuous in high-velocity continuous/“moving” fluidization operations and provides more insights to the transitions between the flow regimes for industrial design and practice.     

Absence of thermal polymers in potato-chip frying oils

Summary The problem of thermal polymers of acceptable flavor in potato-chip-frying oils has been discussed from the standpoint of potentiality of such polymers forming during commercial frying operations. Publications on heat-abused oils have been critically reviewed, and many of these have been shown to yield findings irrelevant to practical operations. Conclusions based upon such studies should not be extended beyond the scope of the findings reported. The change in iodine value has been shown to constitute a simple and highly precise method to determine for survey purposes whether thermal polymers may have formed in the oils used in a given industry. Such a survey has now been completed covering the operations of 89 different potato chip manufacturers, using all types of frying oils. A 1% decrease in the iodine value of the oils in commercial use has been noted. Whereas this change in iodine value is statistically significant, it is shown to have no nutritional significance. The constancy in composition of the frying oils—heated as compared to fresh—and the results of physico-chemical studies, noted in a related study (21), support the present conclusion that thermal polymers are absent from the oils employed in the commercial manufacture of potato chips. Presented at the 20th Annual Conference, National Potato Chip Institute, Dallas, Tex., January 21, 1957.     

Downflow of solids in standpipes

General two-phase theory is applied to the flow of gas-solid mixtures in standpipes. It is shown that at a fixed flow rate both fluidized bed flow and packed bed flow can coexist in the same standpipe. Matsen's analysis of standpipe flow is extended and a general method for determining flow pattern and gas entrainment rate in standpipe flow is described. Data from a commercial standpipe in a fluid bed catalytic cracking unit are analysed. The analysis shows that fluidized bed flow occurs in the standpipe in support of Matsen's work on standpipe flow in another fluid bed catalytic cracking system.Flow instability, in standpipe is discussed in the light of this work and a mechanism of flow instability based on transition in flow pattern is postulated.     

甲苯歧化与C9芳烃烷基转移反应动力学模型和模拟分析

A new kinetic model for commercial unit of toluene disproportionation and C9-armatiocs transalkylation is developed based on the reported reaction scheme.A time based catalyst deactivation function taking weight hourly space velocity（WHSV）into account is incorporated into the model,which reasonably accounts for the loss in activity because of coke deposition on the surface of catalyst during long-term operation.The kinetic parameters are benchmarked with several sets of balanced plant data and estimated by the differential variable metric optimiza- tion method.Sets of plant data at different operating conditions are applied to make sure validation of the model and the results show a good agreement between the model predictions and plant observations.The simulation analysis of key variables such as temperature and WHSV affecting process performance is discussed in detail,giving the guidance to select suitable operating conditions.     

Development and application of ex-situ presulfurization technology for hydrotreating catalysts in China

The development and application of ex-situ presulfurization (EPRES) technology for hydrotreating catalysts has been reviewed in the present article. The studies in laboratory scale and commercial practice indicated that the adoption of the EPRES catalyst in industrial application can significantly enhance the degree of presulfurization of metal oxide components, shorten the start-up period, and effectively reduce the environmental impact as well as the danger of start-up procedure in industrial hydrotreating unit. This catalyst has been proved to be versatile for different types of hydrogenation reactions. Different types of active site models are also discussed for better understanding the nature of presulfurized catalysts.     

Product design with glass fiber reinforced polymer blends,with potential applications in recycling

This paper addresses the issue of compositional variation in multiphase, multi-component polymer mixtures equivalent to those found in commingled waste streams, such as those obtained from reclamation/recycling operations of post-consumer containers. By using virgin resins, the effects of variations in the composition of matrices containing high density polyethylene (HDPE) as the major phase on the properties of composites containing varying amounts of glass fiber and different adhesion promoters are studied. The results obtained on injection molded thin-section parts indicate that it is possible, through the addition of glass fibers and in the presence of suitable adhesion promoters, to obtain enhanced and reproducible properties with relatively little dependence on matrix composition. Preliminary structural and flow analyses were performed with commercial software on different types of plastic parts that could be eventually molded from actual mixed waste plastics suitably modified through glass reinforcement. Experimentally generated rheological and mechanical property data on HDPE based blends containing 20 wt% glass fibers and different adhesion promoters were used for the simulation. Issues concerned with injection molding and product performance of glass-fiber reinforced blends are discussed.     

Desolventizing-toasting of extracted soybean flakes: Development of pilot plant equipment and operational procedure

A pilot plant batch desolventizer-toaster (D-T) was designed and built with the intent of producing soybean meals of varied composition, as well as to simulate meals produced in a continuous commercial D-T unit. Trial runs were made first to determine workable loading levels, temperature control and sparge steam generation. Moisture levels after the steam sparge were influenced by the residual hexane content of defatted hexane-wet flakes reaching the D-T. Two moisture levels were used in testing the effectiveness of the toasting operations in producing flakes with low urease activity and trypsin inhibitor levels. The trial runs reported here also provide basic data for current work designed to optimize toasting procedures to produce suitable meals for ongoing animal nutrition studies.     

Exergy analysis of a combined RO, NF, andEDR desalination plant

A brackish water desalination plant in California that incorporates RO, NF, and EDR units was analyzedthermodynamically using actual plant operation data. Exergy flow rates were evaluated throughout the plant, and the exergy flow diagrams were prepared. The rates of exergy destruction and their percentage are indicated on the diagram so that the locations of highest exergy destruction can easily be identified. The analysis shows that most exergy destruction occurs in the pump/motor and the separation units. The fraction of exergy destruction in the pump/motor units is 39.7% for the RO unit, 23.6% for the NF unit, and 54.1 % for the EDR unit. Therefore, using high-efficiency pumps and motors equipped with VFD drives can reduce the cost of desalination significantly. The plant was determined to have a Second Law efficiency of 8.0% for the RO unit, 9.7% for the NF unit, and 6.3% for the EDR unit, which are very low. This indicates that there are major opportunities in the plant to improve thermodynamic: performance by reducing exergy destruction and thus the amount of electrical energy supplied, making the operation of the plant more cost effective.     

集液硫脱气于一体的硫磺收集系统新标准（RSC-D）^TM

从安全及改善粉碎和成型的角度考虑，通常推荐脱气后液硫中的总H2S质量分数小于0．001％。介绍了6种能够满足该指标要求的主要工业脱气技术。所有脱气技术都采用搅动与气提相结合，有些还采用了液体或固体床催化剂和／或冷却技术。重点介绍了Worley Parsons开发的集液硫脱气于一体的硫磺收集新系统（RSC—D）^TM。该系统采用液体喷射泵代替重力自流收集硫磺，因此所有设备都可布置在地面，而且液硫池可远离硫回收装置。新发明消除了重力自流的约束及堵塞问题，改善了硫收集系统的可靠性和操作性。