Liquid conveyance

M.V. Bhatic and P.N. Cheremisinoff, Solid and Liquid Conveying Systems, Technomic, Lancaster, PA, 1982. 

Turbine surface aerators are designed as liquid-conveying devices (turbines). They are arranged in the liquid surface. Their task consists of sucking up liquid and spraying it over the surface. In this way, on the one hand, the liquid in the basin should be well mixed and a flow velocity should prevail on the bottom, which... 

Note. In the older types of Soxhiet extractor, an external tube ran from B up to the top of C for conveying the ascending column of hot vapour. This type had the disadvantage not only of being more easily broken, but also that the condensed liquid in C received very little heat, and therefore the extraction, being carried out by the lukewarm solvent, was usually very slow. 

For fast-setthug slurries, ensuring conveyance is usually the key design issue while pressure drop is somewhat less important. For nonsettling slurries conveyance is not an issue, because the particles do not separate from the liquid. Here, viscous and rheological behavior, which control pressure drop, take on critical importance. 

Sample Withdrawal from Process A number of considerations are involved in the design of sample-withdrawal devices that wih provide representative samples. For example, in a horizontal pipe that conveys process fluid, a sample point on the bottom of the pipe wih collect a maximum amount of rust, scale, or other solid materials being carried along by the process fluid. In a gas stream, such a location will also collect a maximum amount of liquid contaminants. A sample point on the top side of a pipe will, for liquid streams, collec t a... 

When a liquid or solid substance is emitted to the air as particulate matter, its properties and effects may be changed. As a substance is broken up into smaller and smaller particles, more of its surface area is exposed to the air. Under these circumstances, the substance, whatever its chemical composition, tends to combine physically or chemically with other particles or gases in the atmosphere. The resulting combinations are frequently unpredictable. Very small aerosol particles (from 0.001 to 0.1 Im) can act as condensation nuclei to facilitate the condensation of water vapor, thus promoting the formation of fog and ground mist. Particles less than 2 or 3 [Lm in size (about half by weight of the particles suspended in urban air) can penetrate the mucous membrane and attract and convey harmful chemicals such as sulfur dioxide. In order to address the special concerns related to the effects of very fine, iuhalable particulates, EPA replaced its ambient air standards for total suspended particulates (TSP) with standards for particlute matter less than 10 [Lm in size (PM, ). 

A Perkin-Elmer 5000 AAS was used, with an electrically heated quartz tube atomizer. The electrolyte is continuously conveyed by peristaltic pump. The sample solution is introduced into the loop and transported to the electrochemical cell. A constant current is applied to the electrolytic cell. The gaseous reaction products, hydrides and hydrogen, fonued at the cathode, are flowed out of the cell with the carrier stream of argon and separated from the solution in a gas-liquid separator. The hydrides are transported to an electrically heated quartz tube with argon and determined under operating conditions for hydride fonuing elements by AAS. 

Extruded applications of nylon, other than film and monofilcunent, are less commonly encountered because of the low melt viscosity of the polymers. Uses include cable sheathing which requires resistance to abrasion and/or chemical attack, flexible tubing for conveying petrol and other liquids, piping for chemical... 

Solid-gas Mixing of immiscible liquids Pneumatic conveying of solids Fluidized beds... 

Flussigkeits-. liquid, fluid, hydraulic, hydrostatic. -bad, n. liquid bath, -dichtemesser, m. hydrometer, -druck, m. pressure of a liquid, hydrostatic pressure, -ffirderung, /. conveyance of liquids, -gemisch, n. mixture of liquids, liquid mixture, -grad, m. degree of fluidity viscosity. -gradmesser, m. viscosimeter. -Unse, /. (Micros.) immersion objective, -mass, n. liquid measure, -menge. 

Hooding A condition that gives rise to a sharp decline in tray efficiency and a sharp increase in pressure drop. Flooding is commonly due to either an excessive carryover of liquid to the next tray, or to an inability of the system to convey the liquid flow to the tray below. 

Sulphuric acid is frequently made, stored and conveyed in lead. The corrosion resistance is excellent (see Figure 4.15) provided that the sulphate film is not broken in non-passivating conditions. Rupture of the film may be caused by erosion by high velocity liquids and gases containing acid spray. 

If the liquid flow rate is increased above the value required for conveying the solid particles, they will be carried out of the reactor with the liquid. This effect may be of interest in cases where frequent catalyst regeneration is necessary. 

For the transport of coarse particles, the relative velocity between the liquid and solids is an important factor determining the hold-up, and hence the in-line concentration of solids. Cloete et a/. 65) who conveyed sand and glass ballotini particles through vertical... 

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