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The purpose of this study is to focus on simulation of wire mesh demisters in multistage flash desalination (MSF) plants. The simulation is made by the use of computational fluid dynamics (CFD) software.

A steady state and two-dimensional (2D) model was developed to simulate the demister. The model employs an Eulerian-Eulerian approach to simulate the flow of water vapor and brine droplets in the demister. The computational domain included three zones, which are the vapor space above and below the demister and the demister. The demister zone was modeled as a tube bank arrange or as a porous media.

Sensitivity analysis of the model showed the main parameters that affect demister performance are the vapor velocity and the demister permeability. On the other hand, the analysis showed that the vapor temperature has no effect on the pressure drop across the demister.

The developed model was validated against previous literature data as well as real plant data. The analysis shows good agreement between model prediction and data.

This work is the first in the literature to simulate the MSF demister using CFD modeling. This work is part of a group effort to develop a comprehensive CFD simulation for the entire flashing stage of the MSF process, which would provide an extremely efficient and inexpensive design and simulation tool to the desalination community.

A method has been proposed for testing rubber linings in industrial conditions based on a proposed model of coating penetration. The depth of penetration of rubber lining by water has been determined on the basis of investigation results by electrochemical impedance spectroscopy. Verification of the proposed procedure has been performed by comparing the obtained results of electrochemical investigations with determination of the water content in rubber by the gravimetric method. It has been confirmed that the values calculated in accordance with the penetration model correlate with the water content in rubber. Investigation results confirm views on the corrosion aggressiveness of media in different zones of a scrubber working as part of the flue gas desulphurisation installation.

Introduction Although nickel is generally regarded as a corrosion resistant material its resistance to sea water is only moderate. In fast flowing sea water its corrosion rate is very low; of the order of 0.0005 in/yr. Under stagnant conditions, however, it is susceptible to pitting and crevice corrosion attack. Consequently, alloying has been a common method of improving corrosion resistance to obtain a material having the excellent resistance of nickel to fast flowing sea water together with an improved resistance to pitting corrosion.

The use of materials in marine environments has traditionally been associated with ships. However, in recent years, important new industries have grown up which present new material problems. Notable amongst such industries are offshore oil production and desalination (production of fresh water from seawater). Also, requirements for large amounts of cooling water by modern industry have often resulted in siting of plants by the ocean, particularly in arid areas such as the Middle East. This has increased interest in the use of materials for handling seawater.

During the surface treatment of metals, pollutants occur in the pickling plants. Mainly three harmful substances are produced: sulphuric acid corrosives, hydrochloric acid corrosives and mixed acid corrosives. Different processes have been developed to eliminate or at least reduce these pollutants. An interesting and effective method is offered by Keramchemie of Siershahn, West Germany.

The theory is presented of the increase in damping that can be obtained when a damping compound is added to a simple structure vibrating in a bending mode. Consideration has been given to the use of ‘Aquaplas’ damping compound on a vibrating stringer‐skin combination, and it has been shown that the maximum damping ratio is obtained when the material is applied to the stringer flange over the centre 40 per cent of the pin‐ended length of the beam. A preliminary experimental investigation is described, in which damping measurements were made on a simple structural specimen treated with Aquaplas. A new method was used successfully to determine the damping ratio of a heavily damped system. The damping properties of Aquaplas were evaluated, and some of the theoretical conclusions were verified. Some of the results obtained indicate that a more accurate mathematical representation must be sought for the visco‐elastic behaviour of Aquaplas than is provided by the ‘complex stiffness’ method.

FOR those who want a roomy, comfortable car in the £5,000 price range, the Audi 100 must be a short list contender.

Low installation and running costs, coupled with reduced maintenance requirements and improved levels of safety, are the principal features of a new air pollution control system for use within the plastics processing and coatings industries. The condenser filtration system from the Environmental and Thermal Engineering Division of the AELETE Group has applications wherever visible emissions due to hydrocarbon contaminants are generated.

The design engineer concerned with the construction of chemical plant is faced with a bewildering diversity of materials from which he can select; this diversity continues to increase with the major progress that has been made in the development of improved materials. Metallic materials, which play a dominant role in the chemical industry for major components, are exposed to increasingly aggressive environments. Important advances have been made in developing modified steels and alloys to meet these new demands in a cost effective manner. Traditionally, high nickel alloys and stainless steels have featured strongly in this industry; new knowledge of the working environment and new materials development will ensure that they continue to do so.