Rechnergestützte Konfigurierung von RI-Fließbildern am Beispiel von Pumpen

Knowledge-based Design of PI Diagrams Exemplified for Pumps in Chemical Plant. To date, computer-aided design for flow-sheets has focussed on drawing procedures and reports extracted from these drawings. Today's software technology offers important potential which has still not been fully exploited, e.g. for the design of PI diagrams as front-end application of CAD systems. PI diagrams for process units can be designed by means of knowledge-based systems. The input information which has to be supplied by the process engineer comprises e.g. physico-chemical properties, process conditions and start-up and shut-down procedures. The results are PI diagrams as well as the documentation of the design criteria and operating instructions if manual operations on site are necessary. The potential of knowledge-based computer-aided design of PI diagrams is demonstrated in the case of pumps in chemical plant.     

Über den Einfluß von Chlorkohlenwasserstoffinsecticiden auf Radikalreaktionen von Methyloleat

Effect of Chlorohydrocarbon-Insecticides on Radical-Reactions of Methyl Oleate Chlorinated hydrocarbons having insecticidal action accelerate the autoxidation of methyl oleate by way of shortening the period of induction phase. Measured on the basis of peroxide-formation, the aforesaid effect increases in the order DDT, DDE, heptachlor and heptachloro epoxide. Apart from the accelerating effect which is common to all the active substances studied, the differences with respect to number and nature of peroxides formed and their further conversion products indicate that the individual chlorohydrocarbons favour certain specific mechanisms in the autoxidation of methyl oleate. In this respect, similar behaviour was exhibited by related substances, such as DDT and DDE on one hand, and heptachlor and heptachloro epoxide on the other.     

Auslegung von Blasensäulen mithilfe von Compartmentmodellen

In bubble columns, the phenomena of mass and heat transfer as well as the reaction are closely linked to the complex fluid dynamics. Compartment modeling offers the opportunity to integrate these phenomena while enabling an axial and radial distribution with acceptable computing effort. This article includes methods for generating the compartment geometry and fluid dynamic parameters of this modeling approach, facilitating the opportunity to optimize an industrial bubble column.     

Wirtschaftliches Aufheizen von Flüssigkeiten mit Hilfe von Dampfstrahl-Anwärmern

Economic Heating of Liquids Using Steam Jet Heaters In the processing of fats and oils many processing steps involve heating. Several examples given include heating of oilseed cookers, rendering of fat-bearing materials in cookers, heating of driers, heating of flow-type and stirred tanks, and direct heating of liquids. Heat transfer is accomplished, either indirectly from a medium at a higher temperature via a heat exchange surface or directly to the product to be heated. The heating capacity must be adjusted to ensure the desired temperature for the respective course of reaction. During this process, the flow of heat to be transferred can vary strongly. Therefore, the flow of steam added to a system must be adjusted with the aid of a vapour pressure regulator. A new type of steam jet heater features such a high regulating capability.     

Photoabbau von PVC-Folien. III. Einfluß von Wärmestabilisatoren

PVC-films containing variable concentrations of thermal stabilizer (dioctyltin bis-(iso-octylthioglycolate)) have been irradiated by a high-pressure mercury lamp under air and nitrogen. The dehydrochlorination and discoloration have been recorded. The main function of the stabilizer is the suppression of absorptions in the visible region. There are indications of a participation of the stabilizer in the photoreaction.     

Untersuchung von Kraftstoffdampf‐Rückhaltesystemen bei Einsatz von ethanolhaltigen Biokraftstoffen

Fuel vapor restraint systems are used in vehicles to avoid discharge of volatile hydrocarbons from fuel tanks. Until 2020 nearly 10 % of all fossil fuels shall be replaced by biofuels upon which bioethanol plays an important role. The topic of this article is the proper operation of fuel vapor restraint systems depending on the composition of bioethanol‐fuel blends. As a first step, activated carbons commonly used in fuel restraint systems are tested. Received results and measured data serve as input for a mathematical model with the intention to simulate the performance of fuel vapor restraint systems depending on bioethanol‐fuel composition.