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1.
The optimal scheduling of multi-product batch process is studied and a new mathematics model targeting the maximum profit is proposed, which can be solved by the modified genetic algorithm (MGA) with mixed coding (sequence coding and decimal coding) developed by us. In which, the partially matched cross over (PMX) and reverse mutation are used for the sequence coding, whereas the arithmetic crossover and heteropic mutation are used for the decimal coding. In axidition, the relationship between production scale and production cost is analyzed and the maximum profit is always a trade-off of the production scale and production cost. Two examples are solved to demonstrate the effectiveness of the method.  相似文献   

2.
ABSTRACTS     
《化工粉体工程设计》2013,(6):I0001-I0002
Process Analysis for Production of Sulfuric Acid and High Belite Cement Using Anhydrite (finished) NING Ai-min, LIU Zhen-ru(Hu' nan Xiangfu New Building Materials Co. , Ltd. , Changde 410000, China) Abstract: Based on the fact that anhydrite is an ideal sulfur resource, and by taking the example of the project for production of sulfuric acid with co- product of high helite cement using anhydrite by Hu' nan Xiangfu New Building Materials Co. , Ltd. , the principle, process follow and equipment for the production of co-production of sulfuric acid and cement using anhydrite are introduced, and the production conditions and process control requirements are described, main issues in the production process of the plant are analyzed and summarized, and it is concluded that the project offers major economic sig- nificance by technical economic analysis.  相似文献   

3.
The key of production planning of refineries is to determine the production planning of units and blending schemes of blends in each period of the plan horizon, since they affect the effective utilization of components of refineries and hence profits. The optimization is difficult, because of many complicated product production–consumption relation-ships in production processes, which are closely related to the running modes of the units. Additional y, the blending products, such as gasoline and diesel, may use multiple blending schemes for their production that increase the complexity of the problem. This paper models the production planning problem as a mixed integer nonlinear programming. Computational experiments for a refinery show the effectiveness of the model. The optimal results give the effective utilization of the self-produced components and increase of the profit.  相似文献   

4.
Various methods for production of polysilicon have been proposed for lowering the production cost and energy consumption, and enhancing productivity, which are critical for industrial applications. The fluidized bed chemical vapor deposition (FBCVD) method is a most promising alternative to conventional ones, but the homogeneous reaction of silane in FBCVD results in unwanted formation of fines, which will affect the product quality and output. There are some other problems, such as heating degeneration due to undesired polysilicon deposition on the walls of the reactor and the heater. This article mainly reviews the technological develop-ment on FBCVD of polycrystalline silicon and the research status for solving the above problems. It also identifies a number of chal-lenges to tackle and principles should be followed in the design of a FBCVD reactor.  相似文献   

5.
The chemical industry is nowadays predominantly using fossil raw materials, but the alternative use of bio-based resources is investigated to account for the foreseeable scarcity of fossil feedstocks. A main challenge of using bio-based feedstocks is the complexity of the impurity profile. For an economic production of bio-based chemicals, the use of intensified processes is inevitable and approaches are needed for the various process intensification techniques to identify their applicability to be used for the production of bio-based components. In the presented study, an approach is shown for the reactive distil ation (RD) technology to identify the most critical bio-based impurities and their impact on the reactive distillation process. The investigated case-study is the production of n-butyl acrylate from acrylic acid and n-butanol. Among al initially identified impurities, the key impurities, having the biggest impact on the product purity in the reactive distil ation process, are found. These impurities are then studied in more detail and an operating window depending on the impurity concentration is identified for the reactive distil ation column. Furthermore, an integrated design of upstream and downstream processes is facilitated, as the presented results can be used in the development of the fermentation processes for the produc-tion of the bio-based reactants by decreasing the concentration of the critical impurities.  相似文献   

6.
ABSTRACTS     
《化工粉体工程设计》2014,(5):I0001-I0002
Design Summary for 10 kt/a Acid Production from Phosphorus Mud
Abstract: For the fact that there is large amount of by-product phosphorus mud from electric furnace phosphorus production in China, and problems of low phosphorus recovery and secondary pollution in many ways for recovery for element phosphorus in it, and based on the actual design of a 10 kt/a acid production plant from phosphorus mud of a yellow phosphorus production enterprise, the process flow, control system, equipment selection and technical features of acid production from phosphorus mud are introduced. The process offers features like high phosphorus recovery, free of secondary pollution, high level of automation, and the ability for continuous production, which is worth of promotion.  相似文献   

7.
Simulation of Fuel Ethanol Production from Lignocellulosic Biomass   总被引:1,自引:0,他引:1  
Models for hydrolysis, fermentation and concentration process, production and utilization of biogas as well as lignin gasification are developed to calculate the heat demand of ethanol production process and the amounts of heat and power generated from residues and wastewater of the process. For the energy analysis, all relevant information about the process streams, physical properties, and mass and energy balances are considered. Energy integration is investigated for establishing a network of facilities for heat and power generation from wastewater and residues treatment aiming at the increase of energy efficiency. Feeding the lignin to an IGCC process, the electric efficiency is increased by 4.4% compared with combustion, which leads to an overall energy efficiency of 53.8%. A detailed sensitivity analysis on energy efficiency is also carried out.  相似文献   

8.
It is well established that hydrogen has the potential to make a significant contribution to the world energy production.In U.S.,majority of hydrogen production plants implement steam methane reforming(SMR) for centralized hydrogen production.However,there is a wide lack of agreement on the nascent stage of using hydrogen as fuel in vehicles industry because of the difficulty in delivery and storage.By performing technological and economic analysis,this work aims to establish the most feasible hydrogen production pathway for automotives in near future.From the evaluation,processes such as thermal cracking of ammonia and centralized hydrogen production followed by bulk delivery are eliminated while on-site steam reforming of methanol and natural gas are the most technologically feasible options.These two processes are further evaluated by comprehensive economic analysis.The results showed that the steam reforming(SR) of natural gas has a shorter payback time and a higher return on investment(ROI) and internal rate of return(IRR).Sensitivity analysis has also been constructed to evaluate the impact of variables like NG feedstock price,capital of investment and operating capacity factor on the overall production cost of hydrogen.Based on this study,natural gas is prompted to be the most economically and technologically available raw material for short-term hydrogen production before the transition to renewable energy source such as solar energy,biomass and wind power.  相似文献   

9.
10.
The methylotrophic yeast Pichia pastoris is a highly successful system for production of a variety of heterologous proteins due to its unique features/abilities for effective protein expression, and tremendous efforts have been made to increase heterologous protein productivity by P. pastoris in recent years. When new engineered yeast strains are constructed and are ready to use for industrial protein production, process control and optimization techniques should be applied to improve the fermentation performance in the following aspects: (1) increase recombinant cell concentrations in fermentor to high density during growth phase; (2) effectively induce heterologous proteins by enhancing/stabilizing titers or concentrations of the proteins during induction phase; (3) decrease operation costs by relieving the working loads of heat-exchange and oxygen supply. This article reviews and discusses the key and commonly used techniques in heterologous protein production by P. pastoris, with the focus on optimizations of fermentation media and basic operation conditions, development of optimal glycerol feeding strategies for achieving high density cultivation of P. pastoris and effective heterologous protein induction methods by regulating specific growth rate, methanol concentration, temperatures, mixture ratio of multi-carbon substrates, etc. Metabolic analysis for recombinant protein production by P. pastoris is also introduced to interpret the mechanism of sub-optimal heterologous protein production and to explore further optimal expression methods.  相似文献   

11.
陈建文 《广东化工》2006,33(6):79-81
乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。  相似文献   

12.
我国聚碳酸酯工业发展概况   总被引:5,自引:2,他引:3  
房梅华  夏冶 《塑料工业》1999,27(3):46-47
介绍我国聚碳酸酯生产能力和消费需求,对聚碳酸酯在信息工业中的应用作了简短介绍  相似文献   

13.
The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003  相似文献   

14.
阐述并比较了几种加压设备在乙炔加压清净过程中的性能和特点。  相似文献   

15.
周江涛  夏勇 《清洗世界》2007,23(5):42-43
采用喷射清洗剂的方法,清洗涡轮叶片积炭。  相似文献   

16.
杀虫磺缓释剂杀钉螺试验报告   总被引:1,自引:0,他引:1  
张楚霜  何再德 《农药》1995,34(12):32-33
杀虫磺缓释剂浸杀成螺、幼螺、螺卵效果好,现场应用缓释片63克/米^2,半年后活螺平均密度下降93.2%,春季施药1次,可达到控制当年钉螺的扩散。  相似文献   

17.
塔设备改造选型的分析   总被引:2,自引:0,他引:2  
黄洁  张学 《化工设计》1997,7(3):23-27
就当前扩产增容中塔设备设计和改造时板式塔和填料塔的选型问题加以分析。在评述目前国内常用的几种塔板和新型填料之后,着重介绍一种新型塔板(导向梯形浮阀塔板)和一种新型填料(波环填料——乾隆帕克)。  相似文献   

18.
为实时监控化学-酶法制备氰氟草酯反应过程,建立了一种该体系中氰氟草酯的RP-HPLC的检测方法。采用SymmetryC18柱(5μm,4.6 mm i.d.×150 mm),以V(甲醇)∶V(水)=80∶20为流动相,流速为1.0 mL/min,紫外检测波长为282 nm,柱温为30℃,进样量为20μL。氰氟草酯在5.0~1000.0 mg/L范围内线性良好,相关系数达到0.9999,检出限为1.0 mg/L,相对标准偏差为0.58%(n=5),加标回收率在92.3%~101.5%之间。  相似文献   

19.
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3. __________ Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008.  相似文献   

20.
应用管理学和市场营销学的基本原理和方法,深入分析我国聚丙烯工业的内部和外部环境、市场状况以及加入WTO后所面临的机遇与挑战.在此基础上,应用SWTO(态势分析法),确认出主要的优势和劣势、机会和威胁,对我国聚丙烯工业的国际竞争力进行结构化的综合分析.  相似文献   

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