ISSN:0009-286X    

DOI:10.1002/cite.330600702

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractOptimal use of energy in the chemical industry.Energy costs represent a considerable proportion of manufacturing costs in the chemical industry. Optimization of energy consumption is therefore an important task, but supply and removal of energy also should be considered in the field. Rising oil prices and a predictable lack of steam from power plants required a new concept of the energy supply at the Ludwigshafen site of BASF. Saving energy turned out to be the best solution, considering the oil price, the costs of investment in power plants and the risks of further developments. Some examples explain the procedure and the results of this concept. Though production has increased by 60% since 1970, the consumption of primary energy has been reduced to less than 50%. Investments in power stations have been avoided, but capital had to be spent in energy saving measures and modifications of supply structures. The processes of productions have been improved, air pollution has decreased, the environment has been relieved. Energy saving remains an important task for the future in spite of present low oil prices.

ISSN:0009-286X    

DOI:10.1002/cite.330600703

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractLogistics in the manufacture of chemical products.This survery covers the fields of location analysis, organization of operational material flow, and materials management, all of which are interlocked with each other. Logistics problems with location analysis lie in the area of infrastructure, procurement, and distribution. The organization of the operational material flow has to be based on a closed concept, taking simultanously into consideration interests of production techniques and of logistics. Special attention has to be paid to the reciprocal effect of plant and storage capacity. With complex production structures simulation models should be used, including a statistical model of the market demands, systematic variation of material flows, and grouping of technical equipment. Target is a minimization of total cost. For market oriented operation of complex productions, integrated materials management systems have to be employed. The systems supply a transparent material flow starting from the market demands via the control of production up to the procurement of raw materials.

ISSN:0009-286X    

DOI:10.1002/cite.330600704

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractInterfaces in medicine.Some 6 × 1013individual cells and a variety of differential structures make human organism a highly complex interfacial system. Interfaces play a predominant role in almost all areas of medicine. A number of topical developments which have led to important advances in medical research and practice are selected from the wealth of known phenomena

ISSN:0009-286X    

DOI:10.1002/cite.330600705

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractModelling multiphase flow in reactors.This paper is intended to enhance the knowledge of two phase reactors. Their performance depends not only on reaction kinetics but essentially on fluid‐dynamically fixed quantities such as volume fractions, dispersion coefficients in the fluid and in the gas phase, as well as the volumetric mass transfer coefficient. These are basically dependent on the slip velocity of the phases and on the internal circulation speed of the fluid. The circulation either results from the fluid passing through the vessel (as in a bubble column) or it has to be effected separately in order to avoid separation. Suspension of solids or aeration of liquids in loop and stirred reactors can serve as examples. Dimensionless groups that characterize the main material and geometric properties can be derived using the slip velocity of the largest stable bubble and a certain circulation parameter. The power of this method will be shown by the characterization of bubble columns and gas‐liquid mixers. Simple laws comparable with those applying to bubble columns emerge when approaching the flooding point of a disc turbine in a tank. Power numbers, gas volume fractions, and volumetric mass transfer coefficients can be bundled over the whole spectrum of the non‐flooded states, when their characteristic quantities are divided by the quantities relating to the flooding

ISSN:0009-286X    

DOI:10.1002/cite.330600706

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractProspects of process control engineering.The future opportunities for process control engineering in chemistry depend upon the joint efforts of users and manufacturers. It is the user's responsibility to ensure that modern system engineering is demanded – he must pay greater attention to higher functionality of process und production control levels. The manufacturer must take account of these wishes in his development work on future control systems – he must expand his modular libraries and spectrum of components and increasingly supply high performance instruments for rationalisation of project realisation and maintenance. Control systems of the foreseeable future will be measured against these requireme

ISSN:0009-286X    

DOI:10.1002/cite.330600707

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330600708

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330600709

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330600710

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0009-286X    

DOI:10.1002/cite.330600711

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY